Canvas get perspective point - javascript

i've a canvas dom element inside a div #content with transform rotateX(23deg) and #view with perspective 990px
<div id="view">
<div id="content">
<canvas></canvas>
</div>
</div>
if i draw a point (300,300) inside canvas, the projected coordinates are different (350, 250).
The real problem is when an object drawn in a canvas is interactive (click o drag and drop), the hit area is translated.
Which equation i've to use? Some kind of matrix?
Thanks for your support.

This is something I am dealing with now. Lets start out with something simple. Let's say your canvas is right up against the top left corner. If you click the mouse and make an arc on that spot it will be good.
canvasDOMObject.onmouseclick = (e) => {
const x = e.clientX;
const y = e.clientY;
}
If your canvas origin is not at client origin you would need to do something like this:
const rect = canvasDOMObject.getBoundingRect();
const x = e.clientX - rect.x;
const y = e.clientY - rect.y;
If you apply some pan, adding pan, when drawing stuff you need to un-pan it, pre-subtract the pan, when capturing the mouse point:
const panX = 30;
const panY = 40;
const rect = canvasDOMObject.getBoundingRect();
const x = e.clientX - rect.x - panX;
const y = e.clientY - rect.y - panY;
...
ctx.save();
ctx.translate(panX, panY);
ctx.beginPath();
ctx.strokeArc(x, y);
ctx.restore();
If you apply, for instance, a scale when you draw it, you would need to un-scale it when capturing the mouse point:
const panX = 30;
const panY = 40;
const scale = 1.5;
const rect = canvasDOMObject.getBoundingRect();
const x = (e.clientX - rect.x - panX) / scale;
const y = (e.clientY - rect.y - panY) / scale;
...
ctx.save();
ctx.translate(panX, panY);
ctx.scale(scale);
ctx.beginPath();
ctx.strokeArc(x, y);
ctx.restore();
The rotation I have not figured out yet but I'm getting there.

Alternative solution.
One way to solve the problem is to trace the ray from the mouse into the page and finding the point on the canvas where that ray intercepts.
You will need to transform the x and y axis of the canvas to match its transform. You will also have to project the ray from the desired point to the perspective point. (defined by x,y,z where z is perspective CSS value)
Note: I could not find much info about CSS perspective math and how it is implemented so it is just guess work from me.
There is a lot of math involved and i had to build a quick 3dpoint object to manage it all. I will warn you that it is not well designed (I dont have the time to inline it where needed) and will incur a heavy GC toll. You should rewrite the ray intercept and remove all the point clone calls and reuse points rather than create new ones each time you need them.
There are a few short cuts. The ray / face intercept assumes that the 3 points defining the face are the actual x and y axis but it does not check that this is so. If you have the wrong axis you will not get the correct pixel coordinate. Also the returned coordinate is relative to the point face.p1 (0,0) and is in the range 0-1 where 0 <= x <= 1 and 0 <= y <= 1 are points on the canvas.
Make sure the canvas resolution matches the display size. If not you will need to scale the axis and the results to fit.
DEMO
The demo project a set of points creating a cross through the center of the canvas. You will notice the radius of the projected circle will change depending on distance from the camera.
Note code is in ES6 and requires Babel to run on legacy browsers.
var divCont = document.createElement("div");
var canvas = document.createElement("canvas");
canvas.width = 400;
canvas.height = 400;
var w = canvas.width;
var h = canvas.height;
var cw = w / 2; // center
var ch = h / 2;
var ctx = canvas.getContext("2d");
// perspectiveOrigin
var px = cw; // canvas center
var py = 50; //
// perspective
var pd = 700;
var mat;
divCont.style.perspectiveOrigin = px + "px "+py+"px";
divCont.style.perspective = pd + "px";
divCont.style.transformStyle = "preserve-3d";
divCont.style.margin = "10px";
divCont.style.border = "1px black solid";
divCont.style.width = (canvas.width+8) + "px";
divCont.style.height = (canvas.height+8) + "px";
divCont.appendChild(canvas);
document.body.appendChild(divCont);
function getMatrix(){ // get canvas matrix
if(mat === undefined){
mat = new DOMMatrix().setMatrixValue(canvas.style.transform);
}else{
mat.setMatrixValue(canvas.style.transform);
}
}
function getPoint(x,y){ // get point on canvas
var ww = canvas.width;
var hh = canvas.height;
var face = createFace(
createPoint(mat.transformPoint(new DOMPoint(-ww / 2, -hh / 2))),
createPoint(mat.transformPoint(new DOMPoint(ww / 2, -hh / 2))),
createPoint(mat.transformPoint(new DOMPoint(-ww / 2, hh / 2)))
);
var ray = createRay(
createPoint(x - ww / 2, y - hh / 2, 0),
createPoint(px - ww / 2, py - hh / 2, pd)
);
return intersectCoord3DRayFace(ray, face);
}
// draw point projected onto the canvas
function drawPoint(x,y){
var p = getPoint(x,y);
if(p !== undefined){
p.x *= canvas.width;
p.y *= canvas.height;
ctx.beginPath();
ctx.arc(p.x,p.y,8,0,Math.PI * 2);
ctx.fill();
}
}
// main update function
function update(timer){
ctx.setTransform(1,0,0,1,0,0); // reset transform
ctx.globalAlpha = 1; // reset alpha
ctx.fillStyle = "green";
ctx.fillRect(0,0,w,h);
ctx.lineWidth = 10;
ctx.strokeRect(0,0,w,h);
canvas.style.transform = "rotateX("+timer/100+"deg)" + " rotateY("+timer/50+"deg)";
getMatrix();
ctx.fillStyle = "gold";
drawPoint(cw,ch);
for(var i = -200; i <= 200; i += 40){
drawPoint(cw + i,ch);
drawPoint(cw ,ch + i);
}
requestAnimationFrame(update);
}
requestAnimationFrame(update);
// Math functions to find x,y pos on plain.
// Warning this code is not built for SPEED and will incure a lot of GC hits
const small = 1e-6;
var pointFunctions = {
add(p){
this.x += p.x;
this.y += p.y;
this.z += p.z;
return this;
},
sub(p){
this.x -= p.x;
this.y -= p.y;
this.z -= p.z;
return this;
},
mul(mag){
this.x *= mag;
this.y *= mag;
this.z *= mag;
return this;
},
mag(){ // get length
return Math.hypot(this.x,this.y,this.z);
},
cross(p){
var p1 = this.clone();
p1.x = this.y * p.z - this.z * p.y;
p1.y = this.z * p.x - this.x * p.z;
p1.z = this.x * p.y - this.y * p.x;
return p1;
},
dot(p){
return this.x * p.x + this.y * p.y + this.z * p.z;
},
isZero(){
return Math.abs(this.x) < small && Math.abs(this.y) < small && Math.abs(this.z) < small;
},
clone(){
return Object.assign({
x : this.x,
y : this.y,
z : this.z,
},pointFunctions);
}
}
function createPoint(x,y,z){
if(y === undefined){ // quick add overloaded for DOMPoint
y = x.y;
z = x.z;
x = x.x;
}
return Object.assign({
x, y, z,
}, pointFunctions);
}
function createRay(p1, p2){
return { p1, p2 };
}
function createFace(p1, p2, p3){
return { p1,p2, p3 };
}
// Returns the x,y coord of ray intercepting face
// ray is defined by two 3D points and is infinite in length
// face is 3 points on the intereceptin plane
// For correct intercept point face p1-p2 should be at 90deg to p1-p3 (x, and y Axis)
// returns unit coordinates x,y on the face with the origin at face.p1
// If there is no solution then returns undefined
function intersectCoord3DRayFace(ray, face ){
var u = face.p2.clone().sub(face.p1);
var v = face.p3.clone().sub(face.p1);
var n = u.cross(v);
if(n.isZero()){
return; // return undefined
}
var vr = ray.p2.clone().sub(ray.p1);
var b = n.dot(vr);
if (Math.abs(b) < small) { // ray is parallel face
return; // no intercept return undefined
}
var w = ray.p1.clone().sub(face.p1);
var a = -n.dot(w);
var uDist = a / b;
var intercept = ray.p1.clone().add(vr.mul(uDist)); // intersect point
var uu = u.dot(u);
var uv = u.dot(v);
var vv = v.dot(v);
var dot = uv * uv - uu * vv;
w = intercept.clone().sub(face.p1);
var wu = w.dot(u);
var wv = w.dot(v);
var x = (uv * wv - vv * wu) / dot;
var y = (uv * wu - uu * wv) / dot;
return {x,y};
}

Related

Pure Javascript particle repeller from base64 encoded png

I have some js code that i copied from a youtube tutorial and adapted for my own project to fill the header, the code works as intended and it works when the viewport is smaller than around 1200px, however when i put firefox into full screen the animation does not play & the image is being stretched, not retaining its aspect ratio. I do have a 10/15 year old gpu so i'm guessing thats half my issue. The script uses a png image file of 100x100 pixels, which it then converts into particle color values. Can this be optimized or made to run better. it seems that the wider the viewport the longer the animation takes to kick in, until it finally stops & doesn't work. full screen= [2550x1440]...
The original tutorial is here: Pure Javascript Particle Animations & to convert an image to base64 encoding is here: Image to base64.
HTML:
<html>
<body>
<canvas id="CanV"></canvas>
</body>
</html>
CSS:
#Canv{
position:absolute;
top:-1px;left:-2px;
z-index:67;
width:100vw !important;
max-height: 264px !important;
min-height: 245px !important;
filter:blur(2.27px);
}
Javascript:
window.addEventListener("DOMContentLoaded",(e)=>{
const canv = document.getElementById('Canv');
const ctx = canv.getContext('2d');
canv.width = window.innerWidth;
canv.height = window.innerHeight/ 3.85;
let particleArray = [];
let mouse = {
x: null,
y: null,
radius: 74
}
window.addEventListener('mousemove',(e)=>{
mouse.x = event.x + canv.clientLeft/2;
mouse.y = event.y + canv.clientTop/1.2;
});
function drawImage(){
let imageWidth = png.width; //These to values crop if / sum no.
let imageHeight = png.height;
const data = ctx.getImageData(0, 0, imageWidth, imageHeight); //Gets img data for particles
ctx.clearRect(0,0, canv.width, canv.height); // Clears the original img as its now being stored in the variable data.
class Particle {
constructor(x, y, color, size){
this.x = x + canv.width/2 - png.width * 174, //Chngd Ok:74
this.y = y + canv.height/2 - png.height * 32, //Ch<2 Ok:16
this.color = color,
this.size = 2.28, // Particle Size > Changed this value. from 2 i think!.
this.baseX = x + canv.width/1.8 - png.width * 3.1, //Chngd ok:5.1
this.baseY = y + canv.height/1.2 - png.height * 2.8,
this.density = (Math.random() * 14) + 2;
}
draw() {
ctx.beginPath(); // this creates the sort of force field around the mouse pointer.
ctx.arc(this.x, this.y, this.size, 0, Math.PI * 2);
ctx.closePath();
ctx.fill();
}
update() {
ctx.fillStyle = this.color;
// Collision detection
let dx = mouse.x - this.x;
let dy = mouse.y - this.y;
let distance = Math.sqrt(dx * dx + dy * dy);
let forceDirectionX = dx / distance;
let forceDirectionY = dy / distance;
// Max distance, past that the force will be 0
const maxDistance = 144;
let force = (maxDistance - distance) / maxDistance;
if (force < 0) force = 0;
let directionX = (forceDirectionX * force * this.density * 0.6);
let directionY = (forceDirectionY * force * this.density * 8.7); //Ch.this
if (distance < mouse.radius + this.size) {
this.x -= directionX;
this.y -= directionY;
} else {
if (this.x !== this.baseX){
let dx = this.x - this.baseX;
this.x -= dx/54; // Speed Particles return to ori
} if (this.y !== this.baseY){
let dy = this.y - this.baseY;
this.y -= dy/17; // Speed Particles return to ori
}
}
this.draw();
}
}
function init(){
particleArray = [];
for(let y = 0, y2 = data.height; y<y2; y++){
for(let x =0, x2 = data.width; x<x2; x++){
if(data.data[(y * 4 * data.width) + (x*4) + 3] > 128){
let positionX = x + 25;
let positionY = y + 45; // Co-ords on Canv
let color = "rgb(" + data.data[(y * 4 * data.width) + (x * 4)] + "," +
data.data[(y * 4 * data.width) + (x * 4) + 1] + "," +
data.data[(y * 4 * data.width) + (x * 4) + 2] + ")";
particleArray.push(new Particle(positionX * 2, positionY * 2, color));
} /* These number effect png size but its to high */
}
}
}
function animate(){
requestAnimationFrame(animate);
ctx.fillStyle = 'rgba(0,0,0,.07)';
ctx.fillRect(0,0, innerWidth, innerHeight);
for(let i =0; i < particleArray.length; i++){
particleArray[i].update();
}
}
init();
animate();
}
const png = new Image();
png.src = "RemovedBase64StringToBig";
window.addEventListener('load',(e)=>{
console.log('page has loaded');
ctx.drawImage(png, 0, 0);
drawImage();
})
});
have managed to shorten it by about 100 characters by shortening all the variable names > PartArr, ImgWidth, DirX, DirY etc, but apart from minifying it is there any other ways to optimize this? and fix the full screen issue?
I tried to add it to a JSfiddle, So I could link to it here, but I don't think this is allowing the base64 string, its not loading anything anyway. The canvas loads, with the bg just no image or animation.
I've found out what part of the problem is with full screen, the cursor position is actually about 300px to the right of where the actual cursor is, but I still have no idea how to fix this or fix the major lagging performance issues. Guessing its alot to compute even just with 100x100.
One option I can think of to make this perform better would be to move it & its calculations, into its own dedicated web worker & convert the image to Webp but i'm still not very clued up about web workers or how to implement them properly.. Will play around & see what I can put together using All the suggestions in the comments & answers.
I'm adding these links only for future reference, when I come back to this later on:
MDN Canvas Optimizations
Html5Rocks Canvas Performance
Stack Question. Canv ~ Opti
Creating A blob From A Base 64 String in Js
Secondary bonus Question,
is there a maximum file size or max px dimensions,
that can be base64 encoded? only asking this as someone on facebook has recently sent me a question regarding another project with multiple base64 encoded images and I was unsure of the answer..
Shortening your code doesn't help much with performance. I'm using Firefox. To check what's taking your time up the most during browser runs in Firefox, you can read Performance from MDN.
The problem with your solution is your fps is dropping hard. This happens because you are painting each Particle every frame. Imagine how laggy it will be when there are thousands of Particles that you need to paint every frame. This paint call is called from your function Particle.draw (which calls the following: ctx.beginPath, ctx.arc, and ctx.closePath). This function, as said, will be called because of Particle.update for each frame. This is an extremely expensive operation. To improve your fps drastically, you can try to not draw each Particle individually, but rather gather all the Particles' ImageData wholly then placing it in the canvas only once in rAQ (thus only one paint happens). This ImageData is an object that contains the rgba for each pixel on canvas.
In my solution below, I did the following:
For each Particle that is dirty (has been updated), modify the ImageData that is to be put in the canvas
Then, after the whole ImageData has been constructed for one frame, only draw once to the canvas using putImageData. This saves a lot of the time needed to call your function Particle.update to draw each Particle individually.
One other obvious solution is to increase the size of Particles so that there are fewer Particles' pixels that are needed to be processed (to alter ImageData). I've also tweaked the code a little so that the image will always be at least 100px high; you can tweak the maths so that the image will always maintain your aspect ratio and respond to window size.
Here's a working example:
const canvas = document.querySelector('#canvas1')
const ctx = canvas.getContext('2d')
canvas.width = window.innerWidth
canvas.height = window.innerHeight
let canvasWidth = canvas.width
let canvasHeight = canvas.height
let particleArray = []
let imageData = []
// mouse
let mouse = {
x: null,
y: null,
radius: 40
}
window.addEventListener('mousemove', e => {
mouse.x = event.x
mouse.y = event.y
})
function drawImage(width, height) {
let imageWidth = width
let imageHeight = height
const data = ctx.getImageData(0, 0, imageWidth, imageHeight)
class Particle {
constructor(x, y, color, size = 2) {
this.x = Math.round(x + canvas.width / 2 - imageWidth * 2)
this.y = Math.round(y + canvas.height / 2 - imageHeight * 2)
this.color = color
this.size = size
// Records base and previous positions to repaint the canvas to its original background color
this.baseX = Math.round(x + canvas.width / 2 - imageWidth * 2)
this.baseY = Math.round(y + canvas.height / 2 - imageHeight * 2)
this.previousX = null
this.previousY = null
this.density = (Math.random() * 100) + 2
}
stringifyColor() {
return `rgba(${this.color.r}, ${this.color.g}, ${this.color.b}, ${this.color.a}`
}
update() {
ctx.fillStyle = this.stringifyColor()
// collision detection
let dx = mouse.x - this.x
let dy = mouse.y - this.y
let distance = Math.sqrt(dx * dx + dy * dy)
let forceDirectionX = dx / distance
let forceDirectionY = dy / distance
// max distance, past that the force will be 0
const maxDistance = 100
let force = (maxDistance - distance) / maxDistance
if (force < 0) force = 0
let directionX = (forceDirectionX * force * this.density)
let directionY = (forceDirectionY * force * this.density)
this.previousX = this.x
this.previousY = this.y
if (distance < mouse.radius + this.size) {
this.x -= directionX
this.y -= directionY
} else {
// Rounded to one decimal number to as x and y cannot be the same (whole decimal-less integer)
// as baseX and baseY by decreasing using a random number / 20
if (Math.round(this.x) !== this.baseX) {
let dx = this.x - this.baseX
this.x -= dx / 20
}
if (Math.round(this.y) !== this.baseY) {
let dy = this.y - this.baseY
this.y -= dy / 20
}
}
}
}
function createParticle(x, y, size) {
if (data.data[(y * 4 * data.width) + (x * 4) + 3] > 128) {
let positionX = x
let positionY = y
let offset = (y * 4 * data.width) + (x * 4)
let color = {
r: data.data[offset],
g: data.data[offset + 1],
b: data.data[offset + 2],
a: data.data[offset + 3]
}
return new Particle(positionX * 4, positionY * 4, color, size)
}
}
// Instead of drawing each Particle one by one, construct an ImageData that can be
// painted into the canvas at once using putImageData()
function updateImageDataWith(particle) {
let x = particle.x
let y = particle.y
let prevX = particle.previousX
let prevY = particle.previousY
let size = particle.size
if (prevX || prevY) {
let prevMinY = Math.round(prevY - size)
let prevMaxY = Math.round(prevY + size)
let prevMinX = Math.round(prevX - size)
let prevMaxX = Math.round(prevX + size)
for (let y = prevMinY; y < prevMaxY; y++){
for (let x = prevMinX; x < prevMaxX; x++) {
if (y < 0 || y > canvasHeight) continue
else if (x < 0 || x > canvasWidth) continue
else {
let offset = y * 4 * canvasWidth + x * 4
imageData.data[offset] = 255
imageData.data[offset + 1] = 255
imageData.data[offset + 2] = 255
imageData.data[offset + 3] = 255
}
}
}
}
let minY = Math.round(y - size)
let maxY = Math.round(y + size)
let minX = Math.round(x - size)
let maxX = Math.round(x + size)
for (let y = minY; y < maxY; y++){
for (let x = minX; x < maxX; x++) {
if (y < 0 || y > canvasHeight) continue
else if (x < 0 || x > canvasWidth) continue
else {
let offset = y * 4 * canvasWidth + x * 4
imageData.data[offset] = particle.color.r
imageData.data[offset + 1] = particle.color.g
imageData.data[offset + 2] = particle.color.b
imageData.data[offset + 3] = particle.color.a
}
}
}
}
function init() {
particleArray = []
imageData = ctx.createImageData(canvasWidth, canvasHeight)
// Initializing imageData to a blank white "page"
for (let data = 1; data <= canvasWidth * canvasHeight * 4; data++) {
imageData.data[data - 1] = data % 4 === 0 ? 255 : 255
}
const size = 2 // Min size is 2
const step = Math.floor(size / 2)
for (let y = 0, y2 = data.height; y < y2; y += step) {
for (let x = 0, x2 = data.width; x < x2; x += step) {
// If particle's alpha value is too low, don't record it
if (data.data[(y * 4 * data.width) + (x * 4) + 3] > 128) {
let newParticle = createParticle(x, y, size)
particleArray.push(newParticle)
updateImageDataWith(newParticle)
}
}
}
}
function animate() {
requestAnimationFrame(animate)
for (let i = 0; i < particleArray.length; i++) {
let imageDataCanUpdateKey = `${Math.round(particleArray[i].x)}${Math.round(particleArray[i].y)}`
particleArray[i].update()
updateImageDataWith(particleArray[i])
}
ctx.putImageData(imageData, 0, 0)
}
init()
animate()
window.addEventListener('resize', e => {
canvas.width = innerWidth
canvas.height = innerHeight
canvasWidth = canvas.width
canvasHeight = canvas.height
init()
})
}
const png = new Image()
png.src = " 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"
window.addEventListener('load', e => {
// Ensuring height of image is always 100px
let pngWidth = png.width
let pngHeight = png.height
let divisor = pngHeight / 100
let finalWidth = pngWidth / divisor
let finalHeight = pngHeight / divisor
ctx.drawImage(png, 0, 0, finalWidth, finalHeight)
drawImage(finalWidth, finalHeight)
})
#canvas1 {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
}
<canvas id="canvas1"></canvas>
UPDATE 2: I have managed to optimize further. Now it can render FullHD image (1920x1080) without downgrading quality (on my PC it runs at about 20fps).
Take a look this code on JSFiddle (you can also tweak values).
Thanks also goes to #Richard (check out his answer) for idea to put all data in ImageData and make a single draw call. Code on JSFiddle is combination of his and mine optimizations (code below is my old code).
EDIT: Updated JSFiddle link, optimized more by spreading work of stationary particles across multiple frames (for given settings it improves performance for about 10%).
Regarding optimization, you won't achieve much by minifying code (in this case) because code that eats up CPU is runtime intensive (executes each frame). Minification is good for optimizing loading, not runtime execution.
Most of time is spent on drawing, and after some investigation I have found few performance optimizations but these are not enough to make big difference (eg. ctx.closePath() can be omitted and this saves some milliseconds).
What you can do is to either reduce resolution of image or skip some pixels in image in order to reduce work.
Additionally you could spread work across multiple frames to improve frame rate (but keep in mind if you spread it on more than few frames you might start seeing flickering).
Fullscreen issue can be solved by simply re-initializing everything on resize event.
Below is code with mentioned optimizations and fullscreen fix. Sample image is 375x375 pixels.
UPDATE: I played a little with code and I managed to improve further performance by optimizing calls (things I mentioned below code snippet). Code is updated with these changes.
var canv
var ctx
//performance critical parameters
const pixelStep = 2 //default 1; increase for images of higher resolution
const maxParticlesToProcessInOneFrame = 20000
//additional performance oriented paramteres
// Max distance, past that the force will be 0
const maxDistance = 144
const mouseRadius = 74
//customization parameters
const ctxFillStyle = 'rgba(0,0,0,.07)'
const speedOfActivatingParticle = 1
const speedOfRestoringParticle = 0.1
const png = new Image();
const mouse = {
x: null,
y: null
}
window.addEventListener('mousemove', (e) => {
mouse.x = event.x + canv.clientLeft;
mouse.y = event.y + canv.clientTop;
})
class Particle {
constructor(x, y, size) {
this.x = x
this.y = y
this.size = pixelStep
this.baseX = x
this.baseY = y
this.density = (Math.random() * 14) + 2
}
draw() {
//ctx.beginPath(); // this creates the sort of force field around the mouse pointer.
//ctx.arc(this.x, this.y, this.size, 0, Math.PI * 2);
ctx.rect(this.x, this.y, this.size * 2, this.size * 2)
//ctx.closePath();
}
update() {
// Collision detection
let dx = mouse.x - this.x;
let dy = mouse.y - this.y;
let distance = Math.sqrt(dx * dx + dy * dy);
if (distance < mouseRadius + this.size) {
let forceDirectionX = dx / distance;
let forceDirectionY = dy / distance;
let force = (maxDistance - distance) / maxDistance;
if (force < 0)
force = 0;
const forceTimesDensity = force * this.density * speedOfActivatingParticle
let directionX = (forceDirectionX * forceTimesDensity);
let directionY = (forceDirectionY * forceTimesDensity); //Ch.this
this.x -= directionX;
this.y -= directionY;
} else {
if (this.x !== this.baseX) {
let dx = this.x - this.baseX;
this.x -= dx * speedOfRestoringParticle; // Speed Particles return to ori
}
if (this.y !== this.baseY) {
let dy = this.y - this.baseY;
this.y -= dy * speedOfRestoringParticle; // Speed Particles return to ori
}
}
this.draw();
}
}
window.addEventListener('resize', initializeCanvas)
window.addEventListener("load", initializeCanvas, {
once: true
})
let animationFrame = null
function initializeCanvas(e) {
cancelAnimationFrame(animationFrame)
canv = document.getElementById('Canv');
ctx = canv.getContext('2d');
canv.width = window.innerWidth;
canv.height = window.innerHeight;
let particles = {}
function drawImage() {
let imageWidth = png.width; //These to values crop if / sum no.
let imageHeight = png.height;
const data = ctx.getImageData(0, 0, imageWidth, imageHeight); //Gets img data for particles
ctx.clearRect(0, 0, canv.width, canv.height); // Clears the original img as its now being stored in the variable data.
function init() {
particles = {}
for (let y = 0, y2 = data.height; y < y2; y += pixelStep) {
for (let x = 0, x2 = data.width; x < x2; x += pixelStep) {
if (data.data[(y * 4 * data.width) + (x * 4) + 3] > 128) {
let positionX = x
let positionY = y
let color = "rgb(" + data.data[(y * 4 * data.width) + (x * 4)] + "," +
data.data[(y * 4 * data.width) + (x * 4) + 1] + "," +
data.data[(y * 4 * data.width) + (x * 4) + 2] + ")";
let particlesArray = particles[color]
if (!particlesArray)
particlesArray = particles[color] = []
particlesArray.push(new Particle(positionX * 2, positionY * 2))
} /* These number effect png size but its to high */
}
}
}
let particlesProcessed = 0
let animateGenerator = animate()
function* animate() {
particlesProcessed = 0
ctx.fillStyle = ctxFillStyle;
ctx.fillRect(0, 0, innerWidth, innerHeight);
let colors = Object.keys(particles)
for (let j = 0; j < colors.length; j++) {
let color = colors[j]
ctx.fillStyle = color
let particlesArray = particles[color]
ctx.beginPath()
for (let i = 0; i < particlesArray.length; i++) {
particlesArray[i].update()
if (++particlesProcessed > maxParticlesToProcessInOneFrame) {
particlesProcessed = 0
ctx.fill()
yield
ctx.beginPath()
}
}
ctx.fill()
}
}
init();
function animateFrame() {
animationFrame = requestAnimationFrame(() => {
if (animateGenerator.next().done) {
animateGenerator = animate()
}
animateFrame()
})
}
animateFrame()
}
console.log('page has loaded');
ctx.drawImage(png, 0, 0, png.width, png.height);
drawImage();
}
png.src = 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";
body {
margin: 0;
padding: 0;
}
#Canv {
width: 100vw;
height: 100vh;
filter: blur(1.5px);
}
<canvas id="Canv"></canvas>
If you still need to optimize, you could do some optimization regarding ctx.beginPath(), ctx.fill() and ctx.rect() calls. For example, try to combine sibling pixels (pixels that are next to each other) and render them all in one call. Furthermore, you could merge similar colors in single color, but downside is that image will loose quality (depending on how much colors are merged).
Also (if this is option) you might want to set fixed canvas size rather than dynamically sized.
Disclosure: On my PC given code works nicely, but on others it might still have performance issues. For that reason try to play with pixelStep and maxParticlesToProcessInOneFrame variable values.

Circle/rectangle collision response

So I built some time ago a little Breakout clone, and I wanted to upgrade it a little bit, mostly for the collisions. When I first made it I had a basic "collision" detection between my ball and my brick, which in fact considered the ball as another rectangle. But this created an issue with the edge collisions, so I thought I would change it. The thing is, I found some answers to my problem:
for example this image
and the last comment of this thread : circle/rect collision reaction but i could not find how to compute the final velocity vector.
So far I have :
- Found the closest point on the rectangle,
- created the normal and tangent vectors,
And now what I need is to somehow "divide the velocity vector into a normal component and a tangent component; negate the normal component and add the normal and tangent components to get the new Velocity vector" I'm sorry if this seems terribly easy but I could not get my mind around that ...
code :
function collision(rect, circle){
var NearestX = Max(rect.x, Min(circle.pos.x, rect.x + rect.w));
var NearestY = Max(rect.y, Min(circle.pos.y, rect.y + rect.w));
var dist = createVector(circle.pos.x - NearestX, circle.pos.y - NearestY);
var dnormal = createVector(- dist.y, dist.x);
//change current circle vel according to the collision response
}
Thanks !
EDIT: Also found this but I didn't know if it is applicable at all points of the rectangle or only the corners.
Best explained with a couple of diagrams:
Have angle of incidence = angle of reflection. Call this value θ.
Have θ = normal angle - incoming angle.
atan2 is the function for computing the angle of a vector from the positive x-axis.
Then the code below immediately follows:
function collision(rect, circle){
var NearestX = Max(rect.x, Min(circle.pos.x, rect.x + rect.w));
var NearestY = Max(rect.y, Min(circle.pos.y, rect.y + rect.h));
var dist = createVector(circle.pos.x - NearestX, circle.pos.y - NearestY);
var dnormal = createVector(- dist.y, dist.x);
var normal_angle = atan2(dnormal.y, dnormal.x);
var incoming_angle = atan2(circle.vel.y, circle.vel.x);
var theta = normal_angle - incoming_angle;
circle.vel = circle.vel.rotate(2*theta);
}
Another way of doing it is to get the velocity along the tangent and then subtracting twice this value from the circle velocity.
Then the code becomes
function collision(rect, circle){
var NearestX = Max(rect.x, Min(circle.pos.x, rect.x + rect.w));
var NearestY = Max(rect.y, Min(circle.pos.y, rect.y + rect.h));
var dist = createVector(circle.pos.x - NearestX, circle.pos.y - NearestY);
var tangent_vel = dist.normalize().dot(circle.vel);
circle.vel = circle.vel.sub(tangent_vel.mult(2));
}
Both of the code snippets above do basically the same thing in about the same time (probably). Just pick whichever one you best understand.
Also, as #arbuthnott pointed out, there's a copy-paste error in that NearestY should use rect.h instead of rect.w.
Edit: I forgot the positional resolution. This is the process of moving two physics objects apart so that they're no longer intersecting. In this case, since the block is static, we only need to move the ball.
function collision(rect, circle){
var NearestX = Max(rect.x, Min(circle.pos.x, rect.x + rect.w));
var NearestY = Max(rect.y, Min(circle.pos.y, rect.y + rect.h));
var dist = createVector(circle.pos.x - NearestX, circle.pos.y - NearestY);
if (circle.vel.dot(dist) < 0) { //if circle is moving toward the rect
//update circle.vel using one of the above methods
}
var penetrationDepth = circle.r - dist.mag();
var penetrationVector = dist.normalise().mult(penetrationDepth);
circle.pos = circle.pos.sub(penetrationVector);
}
Bat and Ball collision
The best way to handle ball and rectangle collision is to exploit the symmetry of the system.
Ball as a point.
First the ball, it has a radius r that defines all the points r distance from the center. But we can turn the ball into a point and add to the rectangle the radius. The ball is now just a single point moving over time, which is a line.
The rectangle has grown on all sides by radius. The diagram shows how this works.
The green rectangle is the original rectangle. The balls A,B are not touching the rectangle, while the balls C,D are touching. The balls A,D represent a special case, but is easy to solve as you will see.
All motion as a line.
So now we have a larger rectangle and a ball as a point moving over time (a line), but the rectangle is also moving, which means over time the edges will sweep out areas which is too complicated for my brain, so once again we can use symmetry, this time in relative movement.
From the bat's point of view it is stationary while the ball is moving, and from the ball, it is still while the bat is moving. They both see each other move in the opposite directions.
As the ball is now a point, making changes to its movement will only change the line it travels along. So we can now fix the bat in space and subtract its movement from the ball. And as the bat is now fixed we can move its center point to the origin, (0,0) and move the ball in the opposite direction.
At this point we make an important assumption. The ball and bat are always in a state that they are not touching, when we move the ball and/or bat then they may touch. If they do make contact we calculate a new trajectory so that they are not touching.
Two possible collisions
There are now two possible collision cases, one where the ball hits the side of the bat, and one where the ball hits the corner of the bat.
The next images show the bat at the origin and the ball relative to the bat in both motion and position. It is travelling along the red line from A to B then bounces off to C
Ball hits edge
Ball hits corner
As there is symmetry here as well which side or corner is hit does not make any difference. In fact we can mirror the whole problem depending on which size the ball is from the center of the bat. So if the ball is left of the bat then mirror its position and motion in the x direction, and the same for the y direction (you must keep track of this mirror via a semaphore so you can reverse it once the solution is found).
Code
The example does what is described above in the function doBatBall(bat, ball) The ball has some gravity and will bounce off of the sides of the canvas. The bat is moved via the mouse. The bats movement will be transferred to the ball, but the bat will not feel any force from the ball.
const ctx = canvas.getContext("2d");
const mouse = {x : 0, y : 0, button : false}
function mouseEvents(e){
mouse.x = e.pageX;
mouse.y = e.pageY;
mouse.button = e.type === "mousedown" ? true : e.type === "mouseup" ? false : mouse.button;
}
["down","up","move"].forEach(name => document.addEventListener("mouse" + name, mouseEvents));
// short cut vars
var w = canvas.width;
var h = canvas.height;
var cw = w / 2; // center
var ch = h / 2;
const gravity = 1;
// constants and helpers
const PI2 = Math.PI * 2;
const setStyle = (ctx,style) => { Object.keys(style).forEach(key=> ctx[key] = style[key] ) };
// the ball
const ball = {
r : 50,
x : 50,
y : 50,
dx : 0.2,
dy : 0.2,
maxSpeed : 8,
style : {
lineWidth : 12,
strokeStyle : "green",
},
draw(ctx){
setStyle(ctx,this.style);
ctx.beginPath();
ctx.arc(this.x,this.y,this.r-this.style.lineWidth * 0.45,0,PI2);
ctx.stroke();
},
update(){
this.dy += gravity;
var speed = Math.sqrt(this.dx * this.dx + this.dy * this.dy);
var x = this.x + this.dx;
var y = this.y + this.dy;
if(y > canvas.height - this.r){
y = (canvas.height - this.r) - (y - (canvas.height - this.r));
this.dy = -this.dy;
}
if(y < this.r){
y = this.r - (y - this.r);
this.dy = -this.dy;
}
if(x > canvas.width - this.r){
x = (canvas.width - this.r) - (x - (canvas.width - this.r));
this.dx = -this.dx;
}
if(x < this.r){
x = this.r - (x - this.r);
this.dx = -this.dx;
}
this.x = x;
this.y = y;
if(speed > this.maxSpeed){ // if over speed then slow the ball down gradualy
var reduceSpeed = this.maxSpeed + (speed-this.maxSpeed) * 0.9; // reduce speed if over max speed
this.dx = (this.dx / speed) * reduceSpeed;
this.dy = (this.dy / speed) * reduceSpeed;
}
}
}
const ballShadow = { // this is used to do calcs that may be dumped
r : 50,
x : 50,
y : 50,
dx : 0.2,
dy : 0.2,
}
// Creates the bat
const bat = {
x : 100,
y : 250,
dx : 0,
dy : 0,
width : 140,
height : 10,
style : {
lineWidth : 2,
strokeStyle : "black",
},
draw(ctx){
setStyle(ctx,this.style);
ctx.strokeRect(this.x - this.width / 2,this.y - this.height / 2, this.width, this.height);
},
update(){
this.dx = mouse.x - this.x;
this.dy = mouse.y - this.y;
var x = this.x + this.dx;
var y = this.y + this.dy;
x < this.width / 2 && (x = this.width / 2);
y < this.height / 2 && (y = this.height / 2);
x > canvas.width - this.width / 2 && (x = canvas.width - this.width / 2);
y > canvas.height - this.height / 2 && (y = canvas.height - this.height / 2);
this.dx = x - this.x;
this.dy = y - this.y;
this.x = x;
this.y = y;
}
}
//=============================================================================
// THE FUNCTION THAT DOES THE BALL BAT sim.
// the ball and bat are at new position
function doBatBall(bat,ball){
var mirrorX = 1;
var mirrorY = 1;
const s = ballShadow; // alias
s.x = ball.x;
s.y = ball.y;
s.dx = ball.dx;
s.dy = ball.dy;
s.x -= s.dx;
s.y -= s.dy;
// get the bat half width height
const batW2 = bat.width / 2;
const batH2 = bat.height / 2;
// and bat size plus radius of ball
var batH = batH2 + ball.r;
var batW = batW2 + ball.r;
// set ball position relative to bats last pos
s.x -= bat.x;
s.y -= bat.y;
// set ball delta relative to bat
s.dx -= bat.dx;
s.dy -= bat.dy;
// mirror x and or y if needed
if(s.x < 0){
mirrorX = -1;
s.x = -s.x;
s.dx = -s.dx;
}
if(s.y < 0){
mirrorY = -1;
s.y = -s.y;
s.dy = -s.dy;
}
// bat now only has a bottom, right sides and bottom right corner
var distY = (batH - s.y); // distance from bottom
var distX = (batW - s.x); // distance from right
if(s.dx > 0 && s.dy > 0){ return }// ball moving away so no hit
var ballSpeed = Math.sqrt(s.dx * s.dx + s.dy * s.dy); // get ball speed relative to bat
// get x location of intercept for bottom of bat
var bottomX = s.x +(s.dx / s.dy) * distY;
// get y location of intercept for right of bat
var rightY = s.y +(s.dy / s.dx) * distX;
// get distance to bottom and right intercepts
var distB = Math.hypot(bottomX - s.x, batH - s.y);
var distR = Math.hypot(batW - s.x, rightY - s.y);
var hit = false;
if(s.dy < 0 && bottomX <= batW2 && distB <= ballSpeed && distB < distR){ // if hit is on bottom and bottom hit is closest
hit = true;
s.y = batH - s.dy * ((ballSpeed - distB) / ballSpeed);
s.dy = -s.dy;
}
if(! hit && s.dx < 0 && rightY <= batH2 && distR <= ballSpeed && distR <= distB){ // if hit is on right and right hit is closest
hit = true;
s.x = batW - s.dx * ((ballSpeed - distR) / ballSpeed);;
s.dx = -s.dx;
}
if(!hit){ // if no hit may have intercepted the corner.
// find the distance that the corner is from the line segment from the balls pos to the next pos
const u = ((batW2 - s.x) * s.dx + (batH2 - s.y) * s.dy)/(ballSpeed * ballSpeed);
// get the closest point on the line to the corner
var cpx = s.x + s.dx * u;
var cpy = s.y + s.dy * u;
// get ball radius squared
const radSqr = ball.r * ball.r;
// get the distance of that point from the corner squared
const dist = (cpx - batW2) * (cpx - batW2) + (cpy - batH2) * (cpy - batH2);
// is that distance greater than ball radius
if(dist > radSqr){ return } // no hit
// solves the triangle from center to closest point on balls trajectory
var d = Math.sqrt(radSqr - dist) / ballSpeed;
// intercept point is closest to line start
cpx -= s.dx * d;
cpy -= s.dy * d;
// get the distance from the ball current pos to the intercept point
d = Math.hypot(cpx - s.x,cpy - s.y);
// is the distance greater than the ball speed then its a miss
if(d > ballSpeed){ return } // no hit return
s.x = cpx; // position of contact
s.y = cpy;
// find the normalised tangent at intercept point
const ty = (cpx - batW2) / ball.r;
const tx = -(cpy - batH2) / ball.r;
// calculate the reflection vector
const bsx = s.dx / ballSpeed; // normalise ball speed
const bsy = s.dy / ballSpeed;
const dot = (bsx * tx + bsy * ty) * 2;
// get the distance the ball travels past the intercept
d = ballSpeed - d;
// the reflected vector is the balls new delta (this delta is normalised)
s.dx = (tx * dot - bsx);
s.dy = (ty * dot - bsy);
// move the ball the remaining distance away from corner
s.x += s.dx * d;
s.y += s.dy * d;
// set the ball delta to the balls speed
s.dx *= ballSpeed;
s.dy *= ballSpeed;
hit = true;
}
// if the ball hit the bat restore absolute position
if(hit){
// reverse mirror
s.x *= mirrorX;
s.dx *= mirrorX;
s.y *= mirrorY;
s.dy *= mirrorY;
// remove bat relative position
s.x += bat.x;
s.y += bat.y;
// remove bat relative delta
s.dx += bat.dx;
s.dy += bat.dy;
// set the balls new position and delta
ball.x = s.x;
ball.y = s.y;
ball.dx = s.dx;
ball.dy = s.dy;
}
}
// main update function
function update(timer){
if(w !== innerWidth || h !== innerHeight){
cw = (w = canvas.width = innerWidth) / 2;
ch = (h = canvas.height = innerHeight) / 2;
}
ctx.setTransform(1,0,0,1,0,0); // reset transform
ctx.globalAlpha = 1; // reset alpha
ctx.clearRect(0,0,w,h);
// move bat and ball
bat.update();
ball.update();
// check for bal bat contact and change ball position and trajectory if needed
doBatBall(bat,ball);
// draw ball and bat
bat.draw(ctx);
ball.draw(ctx);
requestAnimationFrame(update);
}
requestAnimationFrame(update);
canvas { position : absolute; top : 0px; left : 0px; }
body {font-family : arial; }
Use the mouse to move the bat and hit the ball.
<canvas id="canvas"></canvas>
Flaws with this method.
It is possible to trap the ball with the bat such that there is no valid solution, such as pressing the ball down onto the bottom of the screen. At some point the balls diameter is greater than the space between the wall and the bat. When this happens the solution will fail and the ball will pass through the bat.
In the demo there is every effort made to not loss energy, but over time floating point errors will accumulate, this can lead to a loss of energy if the sim is run without some input.
As the bat has infinite momentum it is easy to transfer a lot of energy to the ball, to prevent the ball accumulating to much momentum I have added a max speed to the ball. if the ball moves quicker than the max speed it is gradually slowed down until at or under the max speed.
On occasion if you move the bat away from the ball at the same speed, the extra acceleration due to gravity can result in the ball not being pushed away from the bat correctly.
Correction of an idea shared above, with adjusting velocity after collision using tangental velocity.
bounciness - constant defined to represent lost force after collision
nv = vector # normalized vector from center of cricle to collision point (normal)
pv = [-vector[1], vector[0]] # normalized vector perpendicular to nv (tangental)
n = dot_product(nv, circle.vel) # normal vector length
t = dot_product(pv, circle.vel) # tangental_vector length
new_v = sum_vectors(multiply_vector(t*bounciness, pv), multiply_vector(-n*self.bounciness, nv)) # new velocity vector
circle.velocity = new_v

html5 canvas triangle with rounded corners

I'm new to HTML5 Canvas and I'm trying to draw a triangle with rounded corners.
I have tried
ctx.lineJoin = "round";
ctx.lineWidth = 20;
but none of them are working.
Here's my code:
var ctx = document.querySelector("canvas").getContext('2d');
ctx.scale(5, 5);
var x = 18 / 2;
var y = 0;
var triangleWidth = 18;
var triangleHeight = 8;
// how to round this triangle??
ctx.beginPath();
ctx.moveTo(x, y);
ctx.lineTo(x + triangleWidth / 2, y + triangleHeight);
ctx.lineTo(x - triangleWidth / 2, y + triangleHeight);
ctx.closePath();
ctx.fillStyle = "#009688";
ctx.fill();
ctx.fillStyle = "#8BC34A";
ctx.fillRect(0, triangleHeight, 9, 126);
ctx.fillStyle = "#CDDC39";
ctx.fillRect(9, triangleHeight, 9, 126);
<canvas width="800" height="600"></canvas>
Could you help me?
Rounding corners
An invaluable function I use a lot is rounded polygon. It takes a set of 2D points that describe a polygon's vertices and adds arcs to round the corners.
The problem with rounding corners and keeping within the constraint of the polygons area is that you can not always fit a round corner that has a particular radius.
In these cases you can either ignore the corner and leave it as pointy or, you can reduce the rounding radius to fit the corner as best possible.
The following function will resize the corner rounding radius to fit the corner if the corner is too sharp and the lines from the corner not long enough to get the desired radius in.
Note the code has comments that refer to the Maths section below if you want to know what is going on.
roundedPoly(ctx, points, radius)
// ctx is the context to add the path to
// points is a array of points [{x :?, y: ?},...
// radius is the max rounding radius
// this creates a closed polygon.
// To draw you must call between
// ctx.beginPath();
// roundedPoly(ctx, points, radius);
// ctx.stroke();
// ctx.fill();
// as it only adds a path and does not render.
function roundedPoly(ctx, points, radiusAll) {
var i, x, y, len, p1, p2, p3, v1, v2, sinA, sinA90, radDirection, drawDirection, angle, halfAngle, cRadius, lenOut,radius;
// convert 2 points into vector form, polar form, and normalised
var asVec = function(p, pp, v) {
v.x = pp.x - p.x;
v.y = pp.y - p.y;
v.len = Math.sqrt(v.x * v.x + v.y * v.y);
v.nx = v.x / v.len;
v.ny = v.y / v.len;
v.ang = Math.atan2(v.ny, v.nx);
}
radius = radiusAll;
v1 = {};
v2 = {};
len = points.length;
p1 = points[len - 1];
// for each point
for (i = 0; i < len; i++) {
p2 = points[(i) % len];
p3 = points[(i + 1) % len];
//-----------------------------------------
// Part 1
asVec(p2, p1, v1);
asVec(p2, p3, v2);
sinA = v1.nx * v2.ny - v1.ny * v2.nx;
sinA90 = v1.nx * v2.nx - v1.ny * -v2.ny;
angle = Math.asin(sinA < -1 ? -1 : sinA > 1 ? 1 : sinA);
//-----------------------------------------
radDirection = 1;
drawDirection = false;
if (sinA90 < 0) {
if (angle < 0) {
angle = Math.PI + angle;
} else {
angle = Math.PI - angle;
radDirection = -1;
drawDirection = true;
}
} else {
if (angle > 0) {
radDirection = -1;
drawDirection = true;
}
}
if(p2.radius !== undefined){
radius = p2.radius;
}else{
radius = radiusAll;
}
//-----------------------------------------
// Part 2
halfAngle = angle / 2;
//-----------------------------------------
//-----------------------------------------
// Part 3
lenOut = Math.abs(Math.cos(halfAngle) * radius / Math.sin(halfAngle));
//-----------------------------------------
//-----------------------------------------
// Special part A
if (lenOut > Math.min(v1.len / 2, v2.len / 2)) {
lenOut = Math.min(v1.len / 2, v2.len / 2);
cRadius = Math.abs(lenOut * Math.sin(halfAngle) / Math.cos(halfAngle));
} else {
cRadius = radius;
}
//-----------------------------------------
// Part 4
x = p2.x + v2.nx * lenOut;
y = p2.y + v2.ny * lenOut;
//-----------------------------------------
// Part 5
x += -v2.ny * cRadius * radDirection;
y += v2.nx * cRadius * radDirection;
//-----------------------------------------
// Part 6
ctx.arc(x, y, cRadius, v1.ang + Math.PI / 2 * radDirection, v2.ang - Math.PI / 2 * radDirection, drawDirection);
//-----------------------------------------
p1 = p2;
p2 = p3;
}
ctx.closePath();
}
You may wish to add to each point a radius eg {x :10,y:10,radius:20} this will set the max radius for that point. A radius of zero will be no rounding.
The maths
The following illistration shows one of two possibilities, the angle to fit is less than 90deg, the other case (greater than 90) just has a few minor calculation differences (see code).
The corner is defined by the three points in red A, B, and C. The circle radius is r and we need to find the green points F the circle center and D and E which will define the start and end angles of the arc.
First we find the angle between the lines from B,A and B,C this is done by normalising the vectors for both lines and getting the cross product. (Commented as Part 1) We also find the angle of line BC to the line at 90deg to BA as this will help determine which side of the line to put the circle.
Now we have the angle between the lines, we know that half that angle defines the line that the center of the circle will sit F but we do not know how far that point is from B (Commented as Part 2)
There are two right triangles BDF and BEF which are identical. We have the angle at B and we know that the side DF and EF are equal to the radius of the circle r thus we can solve the triangle to get the distance to F from B
For convenience rather than calculate to F is solve for BD (Commented as Part 3) as I will move along the line BC by that distance (Commented as Part 4) then turn 90deg and move up to F (Commented as Part 5) This in the process gives the point D and moving along the line BA to E
We use points D and E and the circle center F (in their abstract form) to calculate the start and end angles of the arc. (done in the arc function part 6)
The rest of the code is concerned with the directions to move along and away from lines and which direction to sweep the arc.
The code section (special part A) uses the lengths of both lines BA and BC and compares them to the distance from BD if that distance is greater than half the line length we know the arc can not fit. I then solve the triangles to find the radius DF if the line BD is half the length of shortest line of BA and BC
Example use.
The snippet is a simple example of the above function in use. Click to add points to the canvas (needs a min of 3 points to create a polygon). You can drag points and see how the corner radius adapts to sharp corners or short lines. More info when snippet is running. To restart rerun the snippet. (there is a lot of extra code that can be ignored)
The corner radius is set to 30.
const ctx = canvas.getContext("2d");
const mouse = {
x: 0,
y: 0,
button: false,
drag: false,
dragStart: false,
dragEnd: false,
dragStartX: 0,
dragStartY: 0
}
function mouseEvents(e) {
mouse.x = e.pageX;
mouse.y = e.pageY;
const lb = mouse.button;
mouse.button = e.type === "mousedown" ? true : e.type === "mouseup" ? false : mouse.button;
if (lb !== mouse.button) {
if (mouse.button) {
mouse.drag = true;
mouse.dragStart = true;
mouse.dragStartX = mouse.x;
mouse.dragStartY = mouse.y;
} else {
mouse.drag = false;
mouse.dragEnd = true;
}
}
}
["down", "up", "move"].forEach(name => document.addEventListener("mouse" + name, mouseEvents));
const pointOnLine = {x:0,y:0};
function distFromLines(x,y,minDist){
var index = -1;
const v1 = {};
const v2 = {};
const v3 = {};
const point = P2(x,y);
eachOf(polygon,(p,i)=>{
const p1 = polygon[(i + 1) % polygon.length];
v1.x = p1.x - p.x;
v1.y = p1.y - p.y;
v2.x = point.x - p.x;
v2.y = point.y - p.y;
const u = (v2.x * v1.x + v2.y * v1.y)/(v1.y * v1.y + v1.x * v1.x);
if(u >= 0 && u <= 1){
v3.x = p.x + v1.x * u;
v3.y = p.y + v1.y * u;
dist = Math.hypot(v3.y - point.y, v3.x - point.x);
if(dist < minDist){
minDist = dist;
index = i;
pointOnLine.x = v3.x;
pointOnLine.y = v3.y;
}
}
})
return index;
}
function roundedPoly(ctx, points, radius) {
var i, x, y, len, p1, p2, p3, v1, v2, sinA, sinA90, radDirection, drawDirection, angle, halfAngle, cRadius, lenOut;
var asVec = function(p, pp, v) {
v.x = pp.x - p.x;
v.y = pp.y - p.y;
v.len = Math.sqrt(v.x * v.x + v.y * v.y);
v.nx = v.x / v.len;
v.ny = v.y / v.len;
v.ang = Math.atan2(v.ny, v.nx);
}
v1 = {};
v2 = {};
len = points.length;
p1 = points[len - 1];
for (i = 0; i < len; i++) {
p2 = points[(i) % len];
p3 = points[(i + 1) % len];
asVec(p2, p1, v1);
asVec(p2, p3, v2);
sinA = v1.nx * v2.ny - v1.ny * v2.nx;
sinA90 = v1.nx * v2.nx - v1.ny * -v2.ny;
angle = Math.asin(sinA); // warning you should guard by clampling
// to -1 to 1. See function roundedPoly in answer or
// Math.asin(Math.max(-1, Math.min(1, sinA)))
radDirection = 1;
drawDirection = false;
if (sinA90 < 0) {
if (angle < 0) {
angle = Math.PI + angle;
} else {
angle = Math.PI - angle;
radDirection = -1;
drawDirection = true;
}
} else {
if (angle > 0) {
radDirection = -1;
drawDirection = true;
}
}
halfAngle = angle / 2;
lenOut = Math.abs(Math.cos(halfAngle) * radius / Math.sin(halfAngle));
if (lenOut > Math.min(v1.len / 2, v2.len / 2)) {
lenOut = Math.min(v1.len / 2, v2.len / 2);
cRadius = Math.abs(lenOut * Math.sin(halfAngle) / Math.cos(halfAngle));
} else {
cRadius = radius;
}
x = p2.x + v2.nx * lenOut;
y = p2.y + v2.ny * lenOut;
x += -v2.ny * cRadius * radDirection;
y += v2.nx * cRadius * radDirection;
ctx.arc(x, y, cRadius, v1.ang + Math.PI / 2 * radDirection, v2.ang - Math.PI / 2 * radDirection, drawDirection);
p1 = p2;
p2 = p3;
}
ctx.closePath();
}
const eachOf = (array, callback) => { var i = 0; while (i < array.length && callback(array[i], i++) !== true); };
const P2 = (x = 0, y = 0) => ({x, y});
const polygon = [];
function findClosestPointIndex(x, y, minDist) {
var index = -1;
eachOf(polygon, (p, i) => {
const dist = Math.hypot(x - p.x, y - p.y);
if (dist < minDist) {
minDist = dist;
index = i;
}
});
return index;
}
// short cut vars
var w = canvas.width;
var h = canvas.height;
var cw = w / 2; // center
var ch = h / 2;
var dragPoint;
var globalTime;
var closestIndex = -1;
var closestLineIndex = -1;
var cursor = "default";
const lineDist = 10;
const pointDist = 20;
var toolTip = "";
// main update function
function update(timer) {
globalTime = timer;
cursor = "crosshair";
toolTip = "";
ctx.setTransform(1, 0, 0, 1, 0, 0); // reset transform
ctx.globalAlpha = 1; // reset alpha
if (w !== innerWidth - 4 || h !== innerHeight - 4) {
cw = (w = canvas.width = innerWidth - 4) / 2;
ch = (h = canvas.height = innerHeight - 4) / 2;
} else {
ctx.clearRect(0, 0, w, h);
}
if (mouse.drag) {
if (mouse.dragStart) {
mouse.dragStart = false;
closestIndex = findClosestPointIndex(mouse.x,mouse.y, pointDist);
if(closestIndex === -1){
closestLineIndex = distFromLines(mouse.x,mouse.y,lineDist);
if(closestLineIndex === -1){
polygon.push(dragPoint = P2(mouse.x, mouse.y));
}else{
polygon.splice(closestLineIndex+1,0,dragPoint = P2(mouse.x, mouse.y));
}
}else{
dragPoint = polygon[closestIndex];
}
}
dragPoint.x = mouse.x;
dragPoint.y = mouse.y
cursor = "none";
}else{
closestIndex = findClosestPointIndex(mouse.x,mouse.y, pointDist);
if(closestIndex === -1){
closestLineIndex = distFromLines(mouse.x,mouse.y,lineDist);
if(closestLineIndex > -1){
toolTip = "Click to cut line and/or drag to move.";
}
}else{
toolTip = "Click drag to move point.";
closestLineIndex = -1;
}
}
ctx.lineWidth = 4;
ctx.fillStyle = "#09F";
ctx.strokeStyle = "#000";
ctx.beginPath();
roundedPoly(ctx, polygon, 30);
ctx.stroke();
ctx.fill();
ctx.beginPath();
ctx.strokeStyle = "red";
ctx.lineWidth = 0.5;
eachOf(polygon, p => ctx.lineTo(p.x,p.y) );
ctx.closePath();
ctx.stroke();
ctx.strokeStyle = "orange";
ctx.lineWidth = 1;
eachOf(polygon, p => ctx.strokeRect(p.x-2,p.y-2,4,4) );
if(closestIndex > -1){
ctx.strokeStyle = "red";
ctx.lineWidth = 4;
dragPoint = polygon[closestIndex];
ctx.strokeRect(dragPoint.x-4,dragPoint.y-4,8,8);
cursor = "move";
}else if(closestLineIndex > -1){
ctx.strokeStyle = "red";
ctx.lineWidth = 4;
var p = polygon[closestLineIndex];
var p1 = polygon[(closestLineIndex + 1) % polygon.length];
ctx.beginPath();
ctx.lineTo(p.x,p.y);
ctx.lineTo(p1.x,p1.y);
ctx.stroke();
ctx.strokeRect(pointOnLine.x-4,pointOnLine.y-4,8,8);
cursor = "pointer";
}
if(toolTip === "" && polygon.length < 3){
toolTip = "Click to add a corners of a polygon.";
}
canvas.title = toolTip;
canvas.style.cursor = cursor;
requestAnimationFrame(update);
}
requestAnimationFrame(update);
canvas {
border: 2px solid black;
position: absolute;
top: 0px;
left: 0px;
}
<canvas id="canvas"></canvas>
I started by using #Blindman67 's answer, which works pretty well for basic static shapes.
I ran into the problem that when using the arc approach, having two points right next to each other is very different than having just one point. With two points next to each other, it won't be rounded, even if that is what your eye would expect. This is extra jarring if you are animating the polygon points.
I fixed this by using Bezier curves instead. IMO this is conceptually a little cleaner as well. I just make each corner with a quadratic curve where the control point is where the original corner was. This way, having two points in the same spot is virtually the same as only having one point.
I haven't compared performance but seems like canvas is pretty good at drawing Beziers.
As with #Blindman67 's answer, this doesn't actually draw anything so you will need to call ctx.beginPath() before and ctx.stroke() after.
/**
* Draws a polygon with rounded corners
* #param {CanvasRenderingContext2D} ctx The canvas context
* #param {Array} points A list of `{x, y}` points
* #radius {number} how much to round the corners
*/
function myRoundPolly(ctx, points, radius) {
const distance = (p1, p2) => Math.sqrt((p1.x - p2.x) ** 2 + (p1.y - p2.y) ** 2)
const lerp = (a, b, x) => a + (b - a) * x
const lerp2D = (p1, p2, t) => ({
x: lerp(p1.x, p2.x, t),
y: lerp(p1.y, p2.y, t)
})
const numPoints = points.length
let corners = []
for (let i = 0; i < numPoints; i++) {
let lastPoint = points[i]
let thisPoint = points[(i + 1) % numPoints]
let nextPoint = points[(i + 2) % numPoints]
let lastEdgeLength = distance(lastPoint, thisPoint)
let lastOffsetDistance = Math.min(lastEdgeLength / 2, radius)
let start = lerp2D(
thisPoint,
lastPoint,
lastOffsetDistance / lastEdgeLength
)
let nextEdgeLength = distance(nextPoint, thisPoint)
let nextOffsetDistance = Math.min(nextEdgeLength / 2, radius)
let end = lerp2D(
thisPoint,
nextPoint,
nextOffsetDistance / nextEdgeLength
)
corners.push([start, thisPoint, end])
}
ctx.moveTo(corners[0][0].x, corners[0][0].y)
for (let [start, ctrl, end] of corners) {
ctx.lineTo(start.x, start.y)
ctx.quadraticCurveTo(ctrl.x, ctrl.y, end.x, end.y)
}
ctx.closePath()
}
Styles for joining of lines such as ctx.lineJoin="round" apply to the stroke operation on paths - which is when their width, color, pattern, dash/dotted and similar line style attributes are taken into account.
Line styles do not apply to filling the interior of a path.
So to affect line styles a stroke operation is needed. In the following adaptation of posted code, I've translated canvas output to see the result without cropping, and stroked the triangle's path but not the rectangles below it:
var ctx = document.querySelector("canvas").getContext('2d');
ctx.scale(5, 5);
ctx.translate( 18, 12);
var x = 18 / 2;
var y = 0;
var triangleWidth = 48;
var triangleHeight = 8;
// how to round this triangle??
ctx.beginPath();
ctx.moveTo(x, y);
ctx.lineTo(x + triangleWidth / 2, y + triangleHeight);
ctx.lineTo(x - triangleWidth / 2, y + triangleHeight);
ctx.closePath();
ctx.fillStyle = "#009688";
ctx.fill();
// stroke the triangle path.
ctx.lineWidth = 3;
ctx.lineJoin = "round";
ctx.strokeStyle = "orange";
ctx.stroke();
ctx.fillStyle = "#8BC34A";
ctx.fillRect(0, triangleHeight, 9, 126);
ctx.fillStyle = "#CDDC39";
ctx.fillRect(9, triangleHeight, 9, 126);
<canvas width="800" height="600"></canvas>

How to draw herringbone pattern on html canvas

I Have to draw Herringbone pattern on canvas and fill with image
some one please help me I am new to canvas 2d drawing.
I need to draw mixed tiles with cross pattern (Herringbone)
var canvas = this.__canvas = new fabric.Canvas('canvas');
var canvas_objects = canvas._objects;
// create a rectangle with a fill and a different color stroke
var left = 150;
var top = 150;
var x=20;
var y=40;
var rect = new fabric.Rect({
left: left,
top: top,
width: x,
height: y,
angle:45,
fill: 'rgba(255,127,39,1)',
stroke: 'rgba(34,177,76,1)',
strokeWidth:0,
originX:'right',
originY:'top',
centeredRotation: false
});
canvas.add(rect);
for(var i=0;i<15;i++){
var rectangle = fabric.util.object.clone(getLastobject());
if(i%2==0){
rectangle.left = rectangle.oCoords.tr.x;
rectangle.top = rectangle.oCoords.tr.y;
rectangle.originX='right';
rectangle.originY='top';
rectangle.angle =-45;
}else{
fabric.log('rectangle: ', rectangle.toJSON());
rectangle.left = rectangle.oCoords.tl.x;
rectangle.top = rectangle.oCoords.tl.y;
fabric.log('rectangle: ', rectangle.toJSON());
rectangle.originX='left';
rectangle.originY='top';
rectangle.angle =45;
}
//rectangle.angle -90;
canvas.add(rectangle);
}
fabric.log('rectangle: ', canvas.toJSON());
canvas.renderAll();
function getLastobject(){
var last = null;
if(canvas_objects.length !== 0){
last = canvas_objects[canvas_objects.length -1]; //Get last object
}
return last;
}
How to draw this pattern in canvas using svg or 2d,3d method. If any third party library that also Ok for me.
I don't know where to start and how to draw this complex pattern.
some one please help me to draw this pattern with rectangle fill with dynamic color on canvas.
Here is a sample of the output I need: (herringbone pattern)
I tried something similar using fabric.js library here is my JSFiddle
Trippy disco flooring
To get the pattern you need to draw rectangles one horizontal tiled one space left or right for each row down and the same for the vertical rectangle.
The rectangle has an aspect of width 2 time height.
Drawing the pattern is simple.
Rotating is easy as well the harder part is finding where to draw the tiles for the rotation.
To do that I create a inverse matrix of the rotation (it reverses a rotation). I then apply that rotation to the 4 corners of the canvas 0,0, width,0 width,height and 0,height this gives me 4 points in the rotated space that are at the edges of the canvas.
As I draw the tiles from left to right top to bottom I find the min corners for the top left, and the max corners for the bottom right, expand it out a little so I dont miss any pixels and draw the tiles with a transformation set the the rotation.
As I could not workout what angle you wanted it at the function will draw it at any angle. On is animated, the other is at 60deg clockwise.
Warning demo contains flashing content.
Update The flashing was way to out there, so have made a few changes, now colours are a more pleasing blend and have fixed absolute positions, and have tied the tile origin to the mouse position, clicking the mouse button will cycle through some sizes as well.
const ctx = canvas.getContext("2d");
const colours = []
for(let i = 0; i < 1; i += 1/80){
colours.push(`hsl(${Math.floor(i * 360)},${Math.floor((Math.sin(i * Math.PI *4)+1) * 50)}%,${Math.floor(Math.sin(i * Math.PI *8)* 25 + 50)}%)`)
}
const sizes = [0.04,0.08,0.1,0.2];
var currentSize = 0;
const origin = {x : canvas.width / 2, y : canvas.height / 2};
var size = Math.min(canvas.width * 0.2, canvas.height * 0.2);
function drawPattern(size,origin,ang){
const xAx = Math.cos(ang); // define the direction of xAxis
const xAy = Math.sin(ang);
ctx.setTransform(1,0,0,1,0,0);
ctx.clearRect(0,0,canvas.width,canvas.height);
ctx.setTransform(xAx,xAy,-xAy,xAx,origin.x,origin.y);
function getExtent(xAx,xAy,origin){
const im = [1,0,0,1]; // inverse matrix
const dot = xAx * xAx + xAy * xAy;
im[0] = xAx / dot;
im[1] = -xAy / dot;
im[2] = xAy / dot;
im[3] = xAx / dot;
const toWorld = (x,y) => {
var point = {};
var xx = x - origin.x;
var yy = y - origin.y;
point.x = xx * im[0] + yy * im[2];
point.y = xx * im[1] + yy * im[3];
return point;
}
return [
toWorld(0,0),
toWorld(canvas.width,0),
toWorld(canvas.width,canvas.height),
toWorld(0,canvas.height),
]
}
const corners = getExtent(xAx,xAy,origin);
var startX = Math.min(corners[0].x,corners[1].x,corners[2].x,corners[3].x);
var endX = Math.max(corners[0].x,corners[1].x,corners[2].x,corners[3].x);
var startY = Math.min(corners[0].y,corners[1].y,corners[2].y,corners[3].y);
var endY = Math.max(corners[0].y,corners[1].y,corners[2].y,corners[3].y);
startX = Math.floor(startX / size) - 2;
endX = Math.floor(endX / size) + 2;
startY = Math.floor(startY / size) - 2;
endY = Math.floor(endY / size) + 2;
// draw the pattern
ctx.lineWidth = size * 0.1;
ctx.lineJoin = "round";
ctx.strokeStyle = "black";
var colourIndex = 0;
for(var y = startY; y <endY; y+=1){
for(var x = startX; x <endX; x+=1){
if((x + y) % 4 === 0){
colourIndex = Math.floor(Math.abs(Math.sin(x)*size + Math.sin(y) * 20));
ctx.fillStyle = colours[(colourIndex++)% colours.length];
ctx.fillRect(x * size,y * size,size * 2,size);
ctx.strokeRect(x * size,y * size,size * 2,size);
x += 2;
ctx.fillStyle = colours[(colourIndex++)% colours.length];
ctx.fillRect(x * size,y * size, size, size * 2);
ctx.strokeRect(x * size,y * size, size, size * 2);
x += 1;
}
}
}
}
// Animate it all
var update = true; // flag to indecate something needs updating
function mainLoop(time){
// if window size has changed update canvas to new size
if(canvas.width !== innerWidth || canvas.height !== innerHeight || update){
canvas.width = innerWidth;
canvas.height = innerHeight
origin.x = canvas.width / 2;
origin.y = canvas.height / 2;
size = Math.min(canvas.width, canvas.height) * sizes[currentSize % sizes.length];
update = false;
}
if(mouse.buttonRaw !== 0){
mouse.buttonRaw = 0;
currentSize += 1;
update = true;
}
// draw the patter
drawPattern(size,mouse,time/2000);
requestAnimationFrame(mainLoop);
}
requestAnimationFrame(mainLoop);
mouse = (function () {
function preventDefault(e) { e.preventDefault() }
var m; // alias for mouse
var mouse = {
x : 0, y : 0, // mouse position
buttonRaw : 0,
over : false, // true if mouse over the element
buttonOnMasks : [0b1, 0b10, 0b100], // mouse button on masks
buttonOffMasks : [0b110, 0b101, 0b011], // mouse button off masks
bounds : null,
eventNames : "mousemove,mousedown,mouseup,mouseout,mouseover".split(","),
event(e) {
var t = e.type;
m.bounds = m.element.getBoundingClientRect();
m.x = e.pageX - m.bounds.left - scrollX;
m.y = e.pageY - m.bounds.top - scrollY;
if (t === "mousedown") { m.buttonRaw |= m.buttonOnMasks[e.which - 1] }
else if (t === "mouseup") { m.buttonRaw &= m.buttonOffMasks[e.which - 1] }
else if (t === "mouseout") { m.over = false }
else if (t === "mouseover") { m.over = true }
e.preventDefault();
},
start(element) {
if (m.element !== undefined) { m.remove() }
m.element = element === undefined ? document : element;
m.eventNames.forEach(name => document.addEventListener(name, mouse.event) );
document.addEventListener("contextmenu", preventDefault, false);
},
}
m = mouse;
return mouse;
})();
mouse.start(canvas);
canvas {
position : absolute;
top : 0px;
left : 0px;
}
<canvas id=canvas></canvas>
Un-animated version at 60Deg
const ctx = canvas.getContext("2d");
const colours = ["red","green","yellow","orange","blue","cyan","magenta"]
const origin = {x : canvas.width / 2, y : canvas.height / 2};
var size = Math.min(canvas.width * 0.2, canvas.height * 0.2);
function drawPattern(size,origin,ang){
const xAx = Math.cos(ang); // define the direction of xAxis
const xAy = Math.sin(ang);
ctx.setTransform(1,0,0,1,0,0);
ctx.clearRect(0,0,canvas.width,canvas.height);
ctx.setTransform(xAx,xAy,-xAy,xAx,origin.x,origin.y);
function getExtent(xAx,xAy,origin){
const im = [1,0,0,1]; // inverse matrix
const dot = xAx * xAx + xAy * xAy;
im[0] = xAx / dot;
im[1] = -xAy / dot;
im[2] = xAy / dot;
im[3] = xAx / dot;
const toWorld = (x,y) => {
var point = {};
var xx = x - origin.x;
var yy = y - origin.y;
point.x = xx * im[0] + yy * im[2];
point.y = xx * im[1] + yy * im[3];
return point;
}
return [
toWorld(0,0),
toWorld(canvas.width,0),
toWorld(canvas.width,canvas.height),
toWorld(0,canvas.height),
]
}
const corners = getExtent(xAx,xAy,origin);
var startX = Math.min(corners[0].x,corners[1].x,corners[2].x,corners[3].x);
var endX = Math.max(corners[0].x,corners[1].x,corners[2].x,corners[3].x);
var startY = Math.min(corners[0].y,corners[1].y,corners[2].y,corners[3].y);
var endY = Math.max(corners[0].y,corners[1].y,corners[2].y,corners[3].y);
startX = Math.floor(startX / size) - 4;
endX = Math.floor(endX / size) + 4;
startY = Math.floor(startY / size) - 4;
endY = Math.floor(endY / size) + 4;
// draw the pattern
ctx.lineWidth = 5;
ctx.lineJoin = "round";
ctx.strokeStyle = "black";
for(var y = startY; y <endY; y+=1){
for(var x = startX; x <endX; x+=1){
ctx.fillStyle = colours[Math.floor(Math.random() * colours.length)];
if((x + y) % 4 === 0){
ctx.fillRect(x * size,y * size,size * 2,size);
ctx.strokeRect(x * size,y * size,size * 2,size);
x += 2;
ctx.fillStyle = colours[Math.floor(Math.random() * colours.length)];
ctx.fillRect(x * size,y * size, size, size * 2);
ctx.strokeRect(x * size,y * size, size, size * 2);
x += 1;
}
}
}
}
canvas.width = innerWidth;
canvas.height = innerHeight
origin.x = canvas.width / 2;
origin.y = canvas.height / 2;
size = Math.min(canvas.width * 0.2, canvas.height * 0.2);
drawPattern(size,origin,Math.PI / 3);
canvas {
position : absolute;
top : 0px;
left : 0px;
}
<canvas id=canvas></canvas>
The best way to approach this is to examine the pattern and analyse its symmetry and how it repeats.
You can look at this several ways. For example, you could rotate the patter 45 degrees so that the tiles are plain orthogonal rectangles. But let's just look at it how it is. I am going to assume you are happy with it with 45deg tiles.
Like the tiles themselves, it turns out the pattern has a 2:1 ratio. If we repeat this pattern horizontally and vertically, we can fill the canvas with the completed pattern.
We can see there are five tiles that overlap with our pattern block. However we don't need to draw them all when we draw each pattern block. We can take advantage of the fact that blocks are repeated, and we can leave the drawing of some tiles to later rows and columns.
Let's assume we are drawing the pattern blocks from left to right and top to bottom. Which tiles do we need to draw, at a minimum, to ensure this pattern block gets completely drawn (taking into account adjacent pattern blocks)?
Since we will be starting at the top left (and moving right and downwards), we'll need to draw tile 2. That's because that tile won't get drawn by either the block below us, or the block to the right of us. The same applies to tile 3.
It turns out those two are all we'll need to draw for each pattern block. Tile 1 and 4 will be drawn when the pattern block below us draws their tile 2 and 3 respectively. Tile 5 will be drawn when the pattern block to the south-east of us draws their tile 1.
We just need to remember that we may need to draw an extra column on the right-hand side, and at the bottom, to ensure those end-of-row and end-of-column pattern blocks get completely drawn.
The last thing to work out is how big our pattern blocks are.
Let's call the short side of the tile a and the long side b. We know that b = 2 * a. And we can work out, using Pythagoras Theorem, that the height of the pattern block will be:
h = sqrt(a^2 + a^2)
= sqrt(2 * a^2)
= sqrt(2) * a
The width of the pattern block we can see will be w = 2 * h.
Now that we've worked out how to draw the pattern, let's implement our algorithm.
const a = 60;
const b = 120;
const h = 50 * Math.sqrt(2);
const w = h * 2;
const h2 = h / 2; // How far tile 1 sticks out to the left of the pattern block
// Set of colours for the tiles
const colours = ["red","cornsilk","black","limegreen","deepskyblue",
"mediumorchid", "lightgrey", "grey"]
const canvas = document.getElementById("herringbone");
const ctx = canvas.getContext("2d");
// Set a universal stroke colour and width
ctx.strokeStyle = "black";
ctx.lineWidth = 4;
// Loop through the pattern block rows
for (var y=0; y < (canvas.height + h); y+=h)
{
// Loop through the pattern block columns
for (var x=0; x < (canvas.width + w); x+=w)
{
// Draw tile "2"
// I'm just going to draw a path for simplicity, rather than
// worrying about drawing a rectangle with rotation and translates
ctx.beginPath();
ctx.moveTo(x - h2, y - h2);
ctx.lineTo(x, y - h);
ctx.lineTo(x + h, y);
ctx.lineTo(x + h2, y + h2);
ctx.closePath();
ctx.fillStyle = colours[Math.floor(Math.random() * colours.length)];
ctx.fill();
ctx.stroke();
// Draw tile "3"
ctx.beginPath();
ctx.moveTo(x + h2, y + h2);
ctx.lineTo(x + w - h2, y - h2);
ctx.lineTo(x + w, y);
ctx.lineTo(x + h, y + h);
ctx.closePath();
ctx.fillStyle = colours[Math.floor(Math.random() * colours.length)];
ctx.fill();
ctx.stroke();
}
}
<canvas id="herringbone" width="500" height="400"></canvas>

JavaScript Point Collision with Regular Hexagon

I'm making an HTML5 canvas hexagon grid based system and I need to be able to detect what hexagonal tile in a grid has been clicked when the canvas is clicked.
Several hours of searching and trying my own methods led to nothing, and porting implementations from other languages has simply confused me to a point where my brain is sluggish.
The grid consists of flat topped regular hexagons like in this diagram:
Essentially, given a point and the variables specified in this image as the sizing for every hexagon in the grid (R, W, S, H):
I need to be able to determine whether a point is inside a hexagon given.
An example function call would be pointInHexagon(hexX, hexY, R, W, S, H, pointX, pointY) where hexX and hexY are the coordinates for the top left corner of the bounding box of a hexagonal tile (like the top left corner in the image above).
Is there anyone who has any idea how to do this? Speed isn't much of a concern for the moment.
Simple & fast diagonal rectangle slice.
Looking at the other answers I see that they have all a little over complicated the problem. The following is an order of magnitude quicker than the accepted answer and does not require any complicated data structures, iterators, or generate dead memory and unneeded GC hits. It returns the hex cell row and column for any related set of R, H, S or W. The example uses R = 50.
Part of the problem is finding which side of a rectangle a point is if the rectangle is split diagonally. This is a very simple calculation and is done by normalising the position of the point to test.
Slice any rectangle diagonally
Example a rectangle of width w, and height h split from top left to bottom right. To find if a point is left or right. Assume top left of rectangle is at rx,ry
var x = ?;
var y = ?;
x = ((x - rx) % w) / w;
y = ((y - ry) % h) / h;
if (x > y) {
// point is in the upper right triangle
} else if (x < y) {
// point is in lower left triangle
} else {
// point is on the diagonal
}
If you want to change the direction of the diagonal then just invert one of the normals
x = 1 - x; // invert x or y to change the direction the rectangle is split
if (x > y) {
// point is in the upper left triangle
} else if (x < y) {
// point is in lower right triangle
} else {
// point is on the diagonal
}
Split into sub cells and use %
The rest of the problem is just a matter of splitting the grid into (R / 2) by (H / 2) cells width each hex covering 4 columns and 2 rows. Every 1st column out of 3 will have diagonals. with every second of these column having the diagonal flipped. For every 4th, 5th, and 6th column out of 6 have the row shifted down one cell. By using % you can very quickly determine which hex cell you are on. Using the diagonal split method above make the math easy and quick.
And one extra bit. The return argument retPos is optional. if you call the function as follows
var retPos;
mainLoop(){
retPos = getHex(mouse.x, mouse.y, retPos);
}
the code will not incur a GC hit, further improving the speed.
Pixel to Hex coordinates
From Question diagram returns hex cell x,y pos. Please note that this function only works in the range 0 <= x, 0 <= y if you need negative coordinates subtract the min negative pixel x,y coordinate from the input
// the values as set out in the question image
var r = 50;
var w = r * 2;
var h = Math.sqrt(3) * r;
// returns the hex grid x,y position in the object retPos.
// retPos is created if not supplied;
// argument x,y is pixel coordinate (for mouse or what ever you are looking to find)
function getHex (x, y, retPos){
if(retPos === undefined){
retPos = {};
}
var xa, ya, xpos, xx, yy, r2, h2;
r2 = r / 2;
h2 = h / 2;
xx = Math.floor(x / r2);
yy = Math.floor(y / h2);
xpos = Math.floor(xx / 3);
xx %= 6;
if (xx % 3 === 0) { // column with diagonals
xa = (x % r2) / r2; // to find the diagonals
ya = (y % h2) / h2;
if (yy % 2===0) {
ya = 1 - ya;
}
if (xx === 3) {
xa = 1 - xa;
}
if (xa > ya) {
retPos.x = xpos + (xx === 3 ? -1 : 0);
retPos.y = Math.floor(yy / 2);
return retPos;
}
retPos.x = xpos + (xx === 0 ? -1 : 0);
retPos.y = Math.floor((yy + 1) / 2);
return retPos;
}
if (xx < 3) {
retPos.x = xpos + (xx === 3 ? -1 : 0);
retPos.y = Math.floor(yy / 2);
return retPos;
}
retPos.x = xpos + (xx === 0 ? -1 : 0);
retPos.y = Math.floor((yy + 1) / 2);
return retPos;
}
Hex to pixel
And a helper function that draws a cell given the cell coordinates.
// Helper function draws a cell at hex coordinates cellx,celly
// fStyle is fill style
// sStyle is strock style;
// fStyle and sStyle are optional. Fill or stroke will only be made if style given
function drawCell1(cellPos, fStyle, sStyle){
var cell = [1,0, 3,0, 4,1, 3,2, 1,2, 0,1];
var r2 = r / 2;
var h2 = h / 2;
function drawCell(x, y){
var i = 0;
ctx.beginPath();
ctx.moveTo((x + cell[i++]) * r2, (y + cell[i++]) * h2)
while (i < cell.length) {
ctx.lineTo((x + cell[i++]) * r2, (y + cell[i++]) * h2)
}
ctx.closePath();
}
ctx.lineWidth = 2;
var cx = Math.floor(cellPos.x * 3);
var cy = Math.floor(cellPos.y * 2);
if(cellPos.x % 2 === 1){
cy -= 1;
}
drawCell(cx, cy);
if (fStyle !== undefined && fStyle !== null){ // fill hex is fStyle given
ctx.fillStyle = fStyle
ctx.fill();
}
if (sStyle !== undefined ){ // stroke hex is fStyle given
ctx.strokeStyle = sStyle
ctx.stroke();
}
}
I think you need something like this~
EDITED
I did some maths and here you have it. This is not a perfect version but probably will help you...
Ah, you only need a R parameter because based on it you can calculate H, W and S. That is what I understand from your description.
// setup canvas for demo
var canvas = document.getElementById('canvas');
canvas.width = 300;
canvas.height = 275;
var context = canvas.getContext('2d');
var hexPath;
var hex = {
x: 50,
y: 50,
R: 100
}
// Place holders for mouse x,y position
var mouseX = 0;
var mouseY = 0;
// Test for collision between an object and a point
function pointInHexagon(target, pointX, pointY) {
var side = Math.sqrt(target.R*target.R*3/4);
var startX = target.x
var baseX = startX + target.R / 2;
var endX = target.x + 2 * target.R;
var startY = target.y;
var baseY = startY + side;
var endY = startY + 2 * side;
var square = {
x: startX,
y: startY,
side: 2*side
}
hexPath = new Path2D();
hexPath.lineTo(baseX, startY);
hexPath.lineTo(baseX + target.R, startY);
hexPath.lineTo(endX, baseY);
hexPath.lineTo(baseX + target.R, endY);
hexPath.lineTo(baseX, endY);
hexPath.lineTo(startX, baseY);
if (pointX >= square.x && pointX <= (square.x + square.side) && pointY >= square.y && pointY <= (square.y + square.side)) {
var auxX = (pointX < target.R / 2) ? pointX : (pointX > target.R * 3 / 2) ? pointX - target.R * 3 / 2 : target.R / 2;
var auxY = (pointY <= square.side / 2) ? pointY : pointY - square.side / 2;
var dPointX = auxX * auxX;
var dPointY = auxY * auxY;
var hypo = Math.sqrt(dPointX + dPointY);
var cos = pointX / hypo;
if (pointX < (target.x + target.R / 2)) {
if (pointY <= (target.y + square.side / 2)) {
if (pointX < (target.x + (target.R / 2 * cos))) return false;
}
if (pointY > (target.y + square.side / 2)) {
if (pointX < (target.x + (target.R / 2 * cos))) return false;
}
}
if (pointX > (target.x + target.R * 3 / 2)) {
if (pointY <= (target.y + square.side / 2)) {
if (pointX < (target.x + square.side - (target.R / 2 * cos))) return false;
}
if (pointY > (target.y + square.side / 2)) {
if (pointX < (target.x + square.side - (target.R / 2 * cos))) return false;
}
}
return true;
}
return false;
}
// Loop
setInterval(onTimerTick, 33);
// Render Loop
function onTimerTick() {
// Clear the canvas
canvas.width = canvas.width;
// see if a collision happened
var collision = pointInHexagon(hex, mouseX, mouseY);
// render out text
context.fillStyle = "Blue";
context.font = "18px sans-serif";
context.fillText("Collision: " + collision + " | Mouse (" + mouseX + ", " + mouseY + ")", 10, 20);
// render out square
context.fillStyle = collision ? "red" : "green";
context.fill(hexPath);
}
// Update mouse position
canvas.onmousemove = function(e) {
mouseX = e.offsetX;
mouseY = e.offsetY;
}
#canvas {
border: 1px solid black;
}
<canvas id="canvas"></canvas>
Just replace your pointInHexagon(hexX, hexY, R, W, S, H, pointX, pointY) by the var hover = ctx.isPointInPath(hexPath, x, y).
This is for Creating and copying paths
This is about the Collision Detection
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
var hexPath = new Path2D();
hexPath.lineTo(25, 0);
hexPath.lineTo(75, 0);
hexPath.lineTo(100, 43);
hexPath.lineTo(75, 86);
hexPath.lineTo(25, 86);
hexPath.lineTo(0, 43);
function draw(hover) {
ctx.clearRect(0, 0, canvas.width, canvas.height);
ctx.fillStyle = hover ? 'blue' : 'red';
ctx.fill(hexPath);
}
canvas.onmousemove = function(e) {
var x = e.clientX - canvas.offsetLeft, y = e.clientY - canvas.offsetTop;
var hover = ctx.isPointInPath(hexPath, x, y)
draw(hover)
};
draw();
<canvas id="canvas"></canvas>
I've made a solution for you that demonstrates the point in triangle approach to this problem.
http://codepen.io/spinvector/pen/gLROEp
maths below:
isPointInside(point)
{
// Point in triangle algorithm from http://totologic.blogspot.com.au/2014/01/accurate-point-in-triangle-test.html
function pointInTriangle(x1, y1, x2, y2, x3, y3, x, y)
{
var denominator = ((y2 - y3)*(x1 - x3) + (x3 - x2)*(y1 - y3));
var a = ((y2 - y3)*(x - x3) + (x3 - x2)*(y - y3)) / denominator;
var b = ((y3 - y1)*(x - x3) + (x1 - x3)*(y - y3)) / denominator;
var c = 1 - a - b;
return 0 <= a && a <= 1 && 0 <= b && b <= 1 && 0 <= c && c <= 1;
}
// A Hex is composite of 6 trianges, lets do a point in triangle test for each one.
// Step through our triangles
for (var i = 0; i < 6; i++) {
// check for point inside, if so, return true for this function;
if(pointInTriangle( this.origin.x, this.origin.y,
this.points[i].x, this.points[i].y,
this.points[(i+1)%6].x, this.points[(i+1)%6].y,
point.x, point.y))
return true;
}
// Point must be outside.
return false;
}
Here is a fully mathematical and functional representation of your problem. You will notice that there are no ifs and thens in this code other than the ternary to change the color of the text depending on the mouse position. This whole job is in fact nothing more than pure simple math of just one line;
(r+m)/2 + Math.cos(a*s)*(r-m)/2;
and this code is reusable for all polygons from triangle to circle. So if interested please read on. It's very simple.
In order to display the functionality I had to develop a mimicking model of the problem. I draw a polygon on a canvas by utilizing a simple utility function. So that the overall solution should work for any polygon. The following snippet will take the canvas context c, radius r, number of sides s, and the local center coordinates in the canvas cx and cy as arguments and draw a polygon on the given canvas context at the right position.
function drawPolgon(c, r, s, cx, cy){ //context, radius, sides, center x, center y
c.beginPath();
c.moveTo(cx + r,cy);
for(var p = 1; p < s; p++) c.lineTo(cx + r*Math.cos(p*2*Math.PI/s), cy + r*Math.sin(p*2*Math.PI/s));
c.closePath();
c.stroke();
}
We have some other utility functions which one can easily understand what exactly they are doing. However the most important part is to check whether the mouse is floating over our polygon or not. It's done by the utility function isMouseIn. It's basically calculating the distance and the angle of the mouse position to the center of the polygon. Then, comparing it with the boundaries of the polygon. The boundaries of the polygon can be expressed by simple trigonometry, just like we have calculated the vertices in the drawPolygon function.
We can think of our polygon as a circle with an oscillating radius at the frequency of number of sides. The oscillation's peak is at the given radius value r (which happens to be at the vertices at angle 2π/s where s is the number of sides) and the minimum m is r*Math.cos(Math.PI/s) (each shows at at angle 2π/s + 2π/2s = 3π/s). I am pretty sure the ideal way to express a polygon could be done by the Fourier transformation but we don't need that here. All we need is a constant radius component which is the average of minimum and maximum, (r+m)/2 and the oscillating component with the frequency of number of sides, s and the amplitude value maximum - minimum)/2 on top of it, Math.cos(a*s)*(r-m)/2. Well of course as per Fourier states we might carry on with smaller oscillating components but with a hexagon you don't really need further iteration while with a triangle you possibly would. So here is our polygon representation in math.
(r+m)/2 + Math.cos(a*s)*(r-m)/2;
Now all we need is to calculate the angle and distance of our mouse position relative to the center of the polygon and compare it with the above mathematical expression which represents our polygon. So all together our magic function is orchestrated as follows;
function isMouseIn(r,s,cx,cy,mx,my){
var m = r*Math.cos(Math.PI/s), // the min dist from an edge to the center
d = Math.hypot(mx-cx,my-cy), // the mouse's distance to the center of the polygon
a = Math.atan2(cy-my,mx-cx); // angle of the mouse pointer
return d <= (r+m)/2 + Math.cos(a*s)*(r-m)/2;
}
So the following code demonstrates how you might approach to solve your problem.
// Generic function to draw a polygon on the canvas
function drawPolgon(c, r, s, cx, cy){ //context, radius, sides, center x, center y
c.beginPath();
c.moveTo(cx + r,cy);
for(var p = 1; p < s; p++) c.lineTo(cx + r*Math.cos(p*2*Math.PI/s), cy + r*Math.sin(p*2*Math.PI/s));
c.closePath();
c.stroke();
}
// To write the mouse position in canvas local coordinates
function writeText(c,x,y,msg,col){
c.clearRect(0, 0, 300, 30);
c.font = "10pt Monospace";
c.fillStyle = col;
c.fillText(msg, x, y);
}
// Getting the mouse position and coverting into canvas local coordinates
function getMousePos(c, e) {
var rect = c.getBoundingClientRect();
return { x: e.clientX - rect.left,
y: e.clientY - rect.top
};
}
// To check if mouse is inside the polygone
function isMouseIn(r,s,cx,cy,mx,my){
var m = r*Math.cos(Math.PI/s),
d = Math.hypot(mx-cx,my-cy),
a = Math.atan2(cy-my,mx-cx);
return d <= (r+m)/2 + Math.cos(a*s)*(r-m)/2;
}
// the event listener callback
function mouseMoveCB(e){
var mp = getMousePos(cnv, e),
msg = 'Mouse at: ' + mp.x + ',' + mp.y,
col = "black",
inside = isMouseIn(radius,sides,center[0],center[1],mp.x,mp.y);
writeText(ctx, 10, 25, msg, inside ? "turquoise" : "red");
}
// body of the JS code
var cnv = document.getElementById("myCanvas"),
ctx = cnv.getContext("2d"),
sides = 6,
radius = 100,
center = [150,150];
cnv.addEventListener('mousemove', mouseMoveCB, false);
drawPolgon(ctx, radius, sides, center[0], center[1]);
#myCanvas { background: #eee;
width: 300px;
height: 300px;
border: 1px #ccc solid
}
<canvas id="myCanvas" width="300" height="300"></canvas>
At the redblog there is a full explanation with math and working examples.
The main idea is that hexagons are horizontally spaced by $3/4$ of hexagons size, vertically it is simply $H$ but the column needs to be taken to take vertical offset into account. The case colored red is determined by comparing x to y at 1/4 W slice.

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