I was trying to use a canvas as texture in my aframe project. I found some instructions here. It mentioned:
The texture will automatically refresh itself as the canvas changes.
However, I gave it a try today and the canvas could only be changed / updated in init function. Afterwards the update to canvas cannot be reflected. Here is my implementation:
module.exports = {
'canvas_component': {
schema: {
canvasId: { type: 'string' }
},
init: function () {
this.canvas = document.getElementById(this.data.canvasId);
this.ctx = this.canvas.getContext('2d');
this.ctx.fillStyle = "#FF0000";
this.ctx.fillRect(20, 20, 150, 100);
setTimeout(() => {
this.ctx.fillStyle = "#FFFF00";
this.ctx.fillRect(20, 20, 150, 100);
}, 2000);
}
}
The color change of of the texture was never changed. Is there anything I missed? Thank you so much for any advice.
I could never get it to work with those instructions (never checked out if bug or improper use though), but you can achieve the same with Three.js:
// assuming this is inside an aframe component
init: function() {
// we'll update this manually
this.texture = null
let canvas = document.getElementById("source-canvas");
// wait until the element is ready
this.el.addEventListener('loaded', e => {
// create the texture
this.texture = new THREE.CanvasTexture(canvas);
// get the references neccesary to swap the texture
let mesh = this.el.getObject3D('mesh')
mesh.material.map = this.texture
// if there was a map before, you should dispose it
})
},
tick: function() {
// if the texture is created - update it
if (this.texture) this.texture.needsUpdate = true
}
Check it out in this glitch.
Instead using the tick function, you could update the texture whenever you get any callback from changing the canvas (mouse events, source change).
The docs are out of date, I've made a pull request to update them. Here is the code that shows how to do it now:
src: https://github.com/aframevr/aframe/issues/4878
which points to: https://github.com/aframevr/aframe/blob/b164623dfa0d2548158f4b7da06157497cd4ea29/examples/test/canvas-texture/components/canvas-updater.js
We can quickly turn that into a component like this, for example:
/* global AFRAME */
AFRAME.registerComponent('live-canvas', {
dependencies: ['geometry', 'material'],
schema: {
src: { type: "string", default: "#id"}
},
init() {
if (!document.querySelector(this.data.src)) {
console.error("no such canvas")
return
}
this.el.setAttribute('material',{src:this.data.src})
},
tick() {
var el = this.el;
var material;
material = el.getObject3D('mesh').material;
if (!material.map) {
console.error("no material map")
this.el.removeAttribute('live-canvas')
return;
}
material.map.needsUpdate = true;
}
});
(remember to declate your components before your scene...)
usage:
<body>
<canvas id="example-canvas"></canvas>
<a-scene>
<a-box live-canvas="src:#example-canvas;"></a-box>
</a-scene>
</body>
live glitch code demo here:
https://glitch.com/edit/#!/live-canvas-demo?path=index.html%3A58%3A43
You can of course be more efficient than a tick handler if you just intentionally run the equivalent code manually whenever you update the canvas yourself, if that makes more sense / isn't happening frame-by-frame.
Related
The game I'm creating doesn't require any physics, however you are able to interact when hovering over/clicking on the sprite by using sprite.setInteractive({cursor: "pointer"});, sprite.on('pointermove', function(activePointer) {...}); and similar. However I noticed two issues with that:
The sprite has some area which are transparent. The interactive functions will still trigger when clicking on those transparent areas, which is unideal.
When playing a sprite animation, the interactive area doesn't seem to entirely (at all?) change, thus if the sprite ends on a frame bigger than the previous, there end up being small areas I can't interact with.
One option I thought of was to create a polygon over my sprite, which covers the area I want to be interactive. However before I do that, I simply wanted to ask if there are simpler ways to fix these issues.
Was trying to find an answer for this myself just now..
Think Make Pixel Perfect is what you're looking for.
this.add.sprite(x, y, key).setInteractive(this.input.makePixelPerfect());
https://newdocs.phaser.io/docs/3.54.0/focus/Phaser.Input.InputPlugin-makePixelPerfect
This might not be the best solution, but I would solve this problem like this. (If I don't want to use physics, and if it doesn't impact the performance too much)
I would check in the event-handler, if at the mouse-position the pixel is transparent or so, this is more exact and less work, than using bounding-boxes.
You would have to do some minor calculations, but it should work well.
btw.: if the origin is not 0, you would would have to compensate in the calculations for this. (in this example, the origin offset is implemented)
Here is a demo, for the click event:
let Scene = {
preload ()
{
this.load.spritesheet('brawler', 'https://labs.phaser.io/assets/animations/brawler48x48.png', { frameWidth: 48, frameHeight: 48 });
},
create ()
{
// Animation set
this.anims.create({
key: 'walk',
frames: this.anims.generateFrameNumbers('brawler', { frames: [ 0, 1, 2, 3 ] }),
frameRate: 8,
repeat: -1
});
// create sprite
const cody = this.add.sprite(200, 100).setOrigin(0);
cody.play('walk');
cody.setInteractive();
// just info text
this.mytext = this.add.text(10, 10, 'Click the Sprite, or close to it ...', { fontFamily: 'Arial' });
// event to watch
cody.on('pointerdown', function (pointer) {
// calculate x,y position of the sprite to check
let x = (pointer.x - cody.x) / (cody.displayWidth / cody.width)
let y = (pointer.y - cody.y) / (cody.displayHeight / cody.height);
// just checking if the properties are set
if(cody.anims && cody.anims.currentFrame){
let currentFrame = cody.anims.currentFrame;
let pixelColor = this.textures.getPixel(x, y, currentFrame.textureKey, currentFrame.textureFrame);
// alpha > 0 a visible pixel of the sprite, is clicked
if(pixelColor.a > 0) {
this.mytext.text = 'Hit';
} else {
this.mytext.text = 'No Hit';
}
// just reset the textmessage
setTimeout(_ => this.mytext.text = 'Click the Sprite, or close to it ...' , 1000);
}
}, this);
}
};
const config = {
type: Phaser.AUTO,
width: 400,
height: 200,
scene: Scene
};
const game = new Phaser.Game(config);
<script src="https://cdn.jsdelivr.net/npm/phaser#3.55.2/dist/phaser.js"></script>
I have a WEB application, that renders it's entire User Interface in an HTML5 canvas.
Note that I can't change the current application.
Currently, this application is being tested using Selenium.
This is done by simulating a click event at a given location in the browser window.
After the click has been executed, a sleep of 2 seconds is being performed to ensure that the entire UI is ready before moving to the next step.
Due to all the 'wait' statements, testing the application is very slow.
Therefore, I thought it was an idea to intercept all calls to the HTML5 canvas.
That way I can rely on the triggered events to know if the UI is ready to move to the next step.
Assume that I have the following code in my application that renders the canvas.
var canvas = document.getElementById("canvasElement");
var ctx = canvas.getContext("2d");
ctx.fillStyle = "green";
ctx.fillRect(10, 10, 100, 100);
Is there a way to intercept the 'fillRect' event?
I tought something along the lines:
var canvasProxy = document.getElementById("canvasElement");
canvasProxy.addEventListener("getContext", function(event) {
console.log("Hello");
});
var canvas = document.getElementById("canvasElement");
var ctx = canvas.getContext("2d");
ctx.fillStyle = "green";
ctx.fillRect(10, 10, 100, 100);
Unforuntately this is not working.
I've created a JSFiddle to play with the example.
https://jsfiddle.net/5cknym74/4/
Amy toughts?
I played a bit around with the JS API and it seems that the following might be working:
// SECTION: Store a reference to all the HTML5 'canvas' element methods.
HTMLCanvasElement.prototype._captureStream = HTMLCanvasElement.prototype.captureStream;
HTMLCanvasElement.prototype._getContext = HTMLCanvasElement.prototype.getContext;
HTMLCanvasElement.prototype._toDataURL = HTMLCanvasElement.prototype.toDataURL;
HTMLCanvasElement.prototype._toBlob = HTMLCanvasElement.prototype.toBlob;
HTMLCanvasElement.prototype._transferControlToOffscreen = HTMLCanvasElement.prototype.transferControlToOffscreen;
HTMLCanvasElement.prototype._mozGetAsFile = HTMLCanvasElement.prototype.mozGetAsFile;
// SECTION: Patch the HTML5 'canvas' element methods.
HTMLCanvasElement.prototype.captureStream = function(frameRate) {
console.log('INTERCEPTING: HTMLCanvasElement.prototype.captureStream');
return this._captureStream(frameRate);
}
HTMLCanvasElement.prototype.getContext = function(contextType, contextAttributes) {
console.log('INTERCEPTING: HTMLCanvasElement.prototype.getContext');
console.log('PROPERTIES:');
console.log(' contextType: ' + contextType);
return this._getContext(contextType, contextAttributes);
}
HTMLCanvasElement.prototype.toDataURL = function(type, encoderOptions) {
console.log('INTERCEPTING: HTMLCanvasElement.prototype.toDataURL');
return this._toDataURL(type, encoderOptions);
}
HTMLCanvasElement.prototype.toBlob = function(callback, mimeType, qualityArgument) {
console.log('INTERCEPTING: HTMLCanvasElement.prototype.toBlob');
return this._toBlob(callback, mimeType, qualityArgument);
}
HTMLCanvasElement.prototype.transferControlToOffscreen = function() {
console.log('INTERCEPTING: HTMLCanvasElement.prototype.transferControlToOffscreen');
return this._transferControlToOffscreen();
}
HTMLCanvasElement.prototype.mozGetAsFile = function(name, type) {
console.log('INTERCEPTING: HTMLCanvasElement.prototype.mozGetAsFile');
return this._mozGetAsFile(name, type);
}
Now that I can intercept the calls, I can find out which calls are responsible that draw a button and react accordingly.
I am using this code now, but it returns a blank transparent image:
$(document).ready(function(){
$("#t").click(function() {
html2canvas(document.querySelector("#bracelet_maker"),
{ onrendered: function(canvas){
src = canvas.toDataURL();
window.open(src); } });
});
});
If I use game.canvas.toDataUrl(); it returns a black image.
This is how the game is started in #bracelet_maker div
var game = new Phaser.Game(width,height,Phaser.AUTO,"bracelte_canvas",{
preload:preload,
create:create,
update:update });
Using Phaser.AUTO will allow either Phaser.WEBGL or Phaser.CANVAS be used, depending upon what your browser supports.
If you switch over to Phaser.CANVAS when creating your new Phaser.Game you should be able to use access the canvas.
For example, within Phaser by binding off the S key:
function create() {
// ...
var screenshotKey = game.input.keyboard.addKey(Phaser.Keyboard.S);
screenshotKey.onDown.add(function () { window.open(game.canvas.toDataURL());
}
There's also preserveDrawingBuffer which should allow you capture from WebGL as well, but it needs to be set early on in the process.
var game = new Phaser.Game(800, 600, Phaser.AUTO, '', {
preload: preload, create: create, update: update
});
game.preserveDrawingBuffer = true;
So I am working on a simple android app using Phaser. But I was looking if it is possible to create a loading screen that uses a spritesheet animation or programmatically do an animation other than just a simple crop how phaser does it?
this.preloadBar = this.add.sprite(50, 170, 'preloaderBar');
this.load.setPreloadSprite(this.preloadBar);
Thanks in advance :)
In order to achieve that, i have a boot state where i initialise various game related utilities and the sprite i want to have during the loading screen. Then i just load the preloader state where everything else is being loaded and i just put the previous sprite on the screen. When everything finishes, main game, or menu state starts.
Here is an example:
Test.Boot.prototype = {
init: function () {
//general game config like scaleManager
},
preload: function () {
this.game.stage.backgroundColor = '#000000';
// the sprite you want to show during loading
this.game.load.atlasJSONHash('logo', 'asset/images/hand.png', 'asset/images/hand.json');
},
create: function () {
this.state.start('Preloader');
}
};
// Preloader.js
Test.Preloader.prototype = {
preload: function() {
//add the animation
this.logo = this.add.sprite(this.world.width/2, this.world.height/2, 'logo');
this.logo.anchor.set(0.5, 0.5);
this.logo.animations.add('shake',[8,9,10,11,12,13,14,15,16,17,17,8,9,8]);
this.logo.animations.play('shake', 60, true);
//load all the other assets
this.game.load.image("hero", "asset/images/hero.png");
this.game.load.image("clouds", "asset/images/sky3.jpg");
//this.game.load.image("rope", "asset/images/rope.png");
this.game.load.atlasJSONHash('items', 'asset/images/items.png', 'asset/images/items.json');
this.game.load.physics('physicsData', 'asset/images/polygon.json');
},
create: function() {
this.game.stage.backgroundColor = '#1589FF';
//A simple fade out effect
this.game.time.events.add(Phaser.Timer.SECOND * 2.0, function() {
var tween = this.add.tween(this.logo)
.to({alpha: 0}, 750, Phaser.Easing.Linear.none);
tween.onComplete.add(function() {
this.logo.destroy();
this.startGame();
}, this);
tween.start();
}, this);
},
startGame: function() {
this.state.start('MainMenu');
},
};
There is a video tutorial with similar technique here if you want to know more.
Building a web page on which I am trying to set an image as the background of the main canvas. The actual image is 1600x805 and I am trying to code the application so that it will scale the image either up or down, according to the dimensions of the user's screen. In Prime.js I have an object that sets the properties of the application's canvas element located in index.html. Here is the code for that object:
function Prime(w,h){
if(!(function(){
return Modernizr.canvas;
})){ alert('Error'); return false; };
this.context = null;
this.self = this;
this.globalCanvasMain.w = w;
this.globalCanvasMain.h = h;
this.globalCanvasMain.set(this.self);
this.background.setBg();
}
Prime.prototype = {
constructor: Prime,
self: this,
globalCanvasMain: {
x: 0,
y: 0,
set: function(ref){
ref.context = document.getElementById('mainCanvas').getContext('2d');
$("#mainCanvas").parent().css('position', 'relative');
$("#mainCanvas").css({left: this.x, top: this.y, position: 'absolute'});
$("#mainCanvas").width(this.w).height(this.h);
}
},
background: {
bg: null,
setBg: function(){
this.bg = new Image();
this.bg.src = 'res/background.jpg';
}
},
drawAll: function(){
this.context.drawImage(this.background.bg, 0,0, this.background.bg.width,this.background.bg.height,
this.globalCanvasMain.x,this.globalCanvasMain.y, this.globalCanvasMain.w,this.globalCanvasMain.h);
}
};
The primary interface through which external objects like this one will interact with the elements in index.html is home.js. Here's what happens there:
$(document).ready(function(){
var prime = new Prime(window.innerWidth,window.innerHeight);
setInterval(prime.drawAll(), 25);
});
For some reason, my call to the context's drawImage function clips only the top left corner from the image and scales it up to the size of the user's screen. Why can I not see the rest of the image?
The problem is that the image has probably not finished loading by the time you call setInterval. If the image is not properly loaded and decoded then drawImage will abort its operation:
If the image isn't yet fully decoded, then nothing is drawn
You need to make sure the image has loaded before attempting to draw it. Do this using the image's onload handler. This operation is asynchronous so it means you also need to deal with either a callback (or a promise):
In the background object you need to supply a callback for the image loading, for example:
...
background: {
bg: null,
setBg: function(callback) {
this.bg = new Image();
this.bg.onload = callback; // supply onload handler before src
this.bg.src = 'res/background.jpg';
}
},
...
Now when the background is set wait for the callback before continue to drawAll() (though, you never seem to set a background which means drawImage tries to draw null):
$(document).ready(function(){
var prime = new Prime(window.innerWidth, window.innerHeight);
// supply a callback function reference:
prime.background.setBg(callbackImageSet);
// image has loaded, now you can draw the background:
function callbackImageSet() {
setInterval(function() {
prime.drawAll();
}, 25);
};
If you want to draw the complete image scaled to fit the canvas you can simplify the call, just supply the new size (and this.globalCanvasMain.x/y doesn't seem to be defined? ):
drawAll: function(){
this.context.drawImage(this.background.bg, 0,0,
this.globalCanvasMain.w,
this.globalCanvasMain.h);
}
I would recommend you to use requestAnimationFrame to draw the image as this will sync with the monitor update.
Also remember to provide callbacks for onerror/onabort on the image object.
There is a problem with the setInterval function. You are not providing proper function reference. The code
setInterval(prime.drawAll(), 25);
execute prime.drawAll only once, and as the result only little part of the image which is being loaded at this moment, is rendered.
Correct code should be:
$(document).ready(function(){
var prime = new Prime(window.innerWidth, window.innerHeight);
setInterval(function() {
prime.drawAll();
}, 25);
});