Set the maximum and current speed of a car in Phaser - javascript

I am making a top-down racing game using the Phaser framework which uses JS. I am having some trouble getting the car to slow down, at the moment it just stops when no button is pressed. I want it to slow down to stopped. Here is my code so far:
create: function () {
//run in canvas mode
this.game.renderer.clearBeforeRender - false;
this.game.renderer.roundPixels = true;
//Add arcade physics
this.game.physics.startSystem(Phaser.Physics.ARCADE);
//Add background sprites
this.game.add.sprite(0, 0, 'background');
this.game.add.sprite(0, 0, 'track');
//Add car sprite
car = this.game.add.sprite(800, 135, 'car-concept');
//Car physics settings
this.game.physics.enable(car, Phaser.Physics.ARCADE);
car.body.drag.set(100);
car.body.maxVelocity.set(200);
car.body.maxAngular = 500;
car.body.angularDrag = 500;
car.body.collideWorldBounds = true;
//Game input
cursors = this.game.input.keyboard.createCursorKeys();
this.game.input.keyboard.addKeyCapture([ Phaser.Keyboard.SPACEBAR]);
//pivot point
car.pivot.x = car.width * .3;
car.pivot.y = car.height * .5;
car.anchor.setTo(0.3, 0.5);
//scale the car
car.scale.setTo(0.3, 0.3);
},
update: function () {
car.body.velocity.x = 0;
car.body.velocity.y = 0;
car.body.angularVelocity = 0;
if(cursors.left.isDown)
{
car.body.angularVelocity = -200;
}
else if(cursors.right.isDown)
{
car.body.angularVelocity = 200;
}
if(cursors.up.isDown)
{
this.game.physics.arcade.velocityFromAngle(car.angle, -200, car.body.velocity)
if(this.currentSpeed < this.maxSpeed)
{
this.currentSpeed += 10;
}
}
else
{
if(this.currentSpeed > 0)
{
this.currentSpeed -= 10;
}
}
if(cursors.down.isDown)
{
this.game.physics.arcade.velocityFromAngle(car.angle, 200, car.body.velocity)
if(this.currentSpeed > 0)
{
this.currentSpeed -= 30;
}
}
},
speed: function()
{
this.maxSpeed = 100;
this.currentSpeed = 0;
},
I have looked a few questions on here about the same problem and this is how I got to the point where I am now. I have set the maxSpeed and currentSpeed but for some reason it won't allow me to actually use it. The console in the browser does not give me any errors, so if anyone can guide me on this, that would be great!
Thanks.

The reason it stops dead is because you're moving it with velocity, not acceleration - and are setting velocity to zero in your update loop (this effectively says "stop, now!").
Remove those lines and in your call to velocityFromAngle you should feed that into body.acceleration instead of body.velocity.
Here is an update loop you can use, although you'll need to mix in your currentSpeed settings and such like:
function update() {
if (cursors.up.isDown)
{
game.physics.arcade.accelerationFromRotation(sprite.rotation, 200, sprite.body.acceleration);
}
else
{
sprite.body.acceleration.set(0);
}
if (cursors.left.isDown)
{
sprite.body.angularVelocity = -300;
}
else if (cursors.right.isDown)
{
sprite.body.angularVelocity = 300;
}
else
{
sprite.body.angularVelocity = 0;
}
}

you never used currentSpeed. You set your speed to -200 and 200 in velocityFromAngle.

Related

Cannot rotate car and tilemap is not fully visible

I am trying to port the following Phaser2 example (https://phaser.io/examples/v2/tilemaps/fill-tiles) into Phaser3. I am experiencing two issues:
I cannot rotate the vehicle as the left/right keys will not work.
I cannot get the tilemap to display correctly, it seems cut off.
import Phaser from "phaser";
const config = {
type: Phaser.AUTO,
parent: "phaser-example",
width: 800,
height: 600,
physics: {
default: 'arcade'
},
scene: {
preload: preload,
create: create,
update: update,
render: render
}
};
const game = new Phaser.Game(config);
let cursors;
let player;
let map;
let speed = 0;
function preload() {
this.load.tilemapTiledJSON('desert', 'desert.json');
this.load.image('tiles', 'https://examples.phaser.io/assets/tilemaps/tiles/tmw_desert_spacing.png')
this.load.image('car', 'http://labs.phaser.io/assets/sprites/car90.png')
}
function create() {
map = this.make.tilemap({ key: 'desert' });
const tiles = map.addTilesetImage('Desert', 'tiles');
const layer = map.createDynamicLayer('Ground', tiles, 0, 0);
cursors = this.input.keyboard.createCursorKeys();
player = this.physics.add.sprite(450, 80, 'car');
this.cameras.main.startFollow(player, true, 0.05, 0.05);
}
function update() {
// Drive forward if cursor up key is pressed down
if (cursors.up.isDown && speed <= 400) {
speed += 10;
} else {
if (speed >= 10) {
speed -= 10
}
}
// Drive backwards if cursor down key is pressed down
if (cursors.down.isDown && speed >= -200) {
speed -= 5;
} else {
if (speed <= -5) {
speed += 5
}
}
// Steer the car
if (cursors.left.isDown) {
player.body.angularVelocity = -5 * (speed / 1000);
} else if (cursors.right.isDown) {
player.body.angularVelocity = 5 * (speed / 1000);
} else {
player.body.angularVelocity = 0;
}
player.body.velocity.x = speed * Math.cos((player.body.angle - 360) * 0.01745);
player.body.velocity.y = speed * Math.sin((player.body.angle - 360) * 0.01745);
}
function render() {
}
How can I fix this?
I loaded the code in a blank project without assets, and was able to see the image missing object rotate. However, it looks like the dependency of speed in angular rotation is too low. If you reduce the decrease in scaling of speed used for calculating angular velocity, you can get the car to turn more quickly.
Proof -> https://stackblitz.com/edit/phaser-2-example-so

Need Javascript Collision Detection in App Lab

I am making a game in the code.org App Lab. The game is based around Player 2 dropping meteors that Player 1 has to dodge. However, I have no idea how to do collision detection. can someone please help? I need a basic collision detection system to lower Player 1's health when a meteor hits them. Feel free to use the x and y values of Player 1, as well as add your own variables. I will give a shout-out to the person who help me. Here is my code:
var x = 104;
var y = 172;
var p1HP = 100;
var meteorCount = 25;
var mousex;
var mousey;
var meteorNum = 0;
//Code below triggers a screen change and music when a button is pressed.
onEvent("startButton", "click", function() {
setScreen("playscreen");
playSound("Brobot-Battle-(8-BIT)---Super-Paper-Mario-(192--kbps).mp3", false);
});
//Code below is basic movement for player.
onEvent("playscreen", "keydown", function(event) {
if (event.key=="w") {
getP1Pos();
setPosition("image2", x, y-8, 100, 100);
} else if (event.key=="a") {
getP1Pos();
setPosition("image2", x-8, y, 100, 100);
} else if (event.key=="d") {
getP1Pos();
setPosition("image2", x+8, y, 100, 100);
} else if (event.key=="s") {
getP1Pos();
setPosition("image2", x, y+8, 100, 100);
}
});
function getP1Pos() {
x = getXPosition("image2");
y = getYPosition("image2");
}
//code below resets the game when a retry button is pressed
onEvent("retry"||"retry2", "click", function( ) {
setScreen("startscreen");
p1HP = 100;
meteorCount = 20;
setText("p1HP", "P1 HP: "+p1HP);
setText("meteorCounter", "P2 METEORS: "+meteorCount);
});
//code below records mouse position
onEvent("playscreen", "mousemove", function(mouse) {
mousex = mouse.x;
mousey = mouse.y;
});
//code below makes the meteors go to the mouse and fall when the screen is clicked
onEvent("playscreen", "click", function() {
stopTimedLoop();
if (meteorNum==5) {
meteorNum = 1;
} else {
meteorNum = meteorNum+1;
}
meteorCount = meteorCount-1;
if (meteorCount==-1) {
setScreen("p1victory");
stopSound("Brobot-Battle-(8-BIT)---Super-Paper-Mario-(192--kbps).mp3");
} else {
setPosition("meteor"+meteorNum, mousex-20, mousey-20, 100, 100);
timedLoop(60, function() {
setPosition("meteor"+meteorNum, getXPosition("meteor"+meteorNum), getYPosition("meteor"+meteorNum) + 40, 100, 100);
});
setText("meteorCounter", "P2 METEORS: "+meteorCount);
}
});
//Insert collision detection algorithm here
I might have something that can work:
sprite.collide(target);
If it doesn't work, then please put the link for your code.org project.

P5.js Draw() function not working as expected in AngularJS directive

I'm trying to integrate the p5.js library in my AngularJS application, having my code run in a directive.
In my plain JavaScript files, Im able to run the draw() method after importing the p5 library globally.
My original code (not the issue):
var mic
var playButton
var volHistory = []
var micIsOn = false
function setup(){
createCanvas(400, 150)
createButtons()
mic = new p5.AudioIn()
}
function draw(){
background(245)
stroke(0, 109, 203)
//populate volHistory
if(micIsOn){
var vol = mic.getLevel()
//check to see if array is empty, if it is empty we do not want to push 0 volume
if(volHistory.length > 0 && vol > 0){
volHistory.push(vol)
//if recording has started, we can now take in vol
} else if(vol > 0) {
volHistory.push(vol)
console.log(volHistory.length)
}
}
//iterate through volHistory and draw
fill(0, 109, 203)
var barWidth = 2;
var offsetWidth = 5;
var offset = 5;
for(var i = 0; i < volHistory.length; i++){
var barHeight = map(volHistory[i], 0, 1, 1, height)
rect(i + offset, (height/2.0) - (barHeight/2.0), barWidth, barHeight, 15);
offset += offsetWidth;
}
//moves wavelength 1 index at a time and account for bar width and offset width
if(volHistory.length * (offsetWidth + barWidth) > width){
volHistory.splice(0, 1)
}
//draw vertical line
stroke(250, 30, 100)
line(volHistory.length + offset, 0, volHistory.length + offset, height)
}
function createButtons(){
playButton = createButton("<img style='width: 50px' src='playbutton.png'/>")
playButton.mousePressed(toggleRecord)
playButton.position(162, 50)
playButton.style("background-color", color(0,0,0,0))
playButton.style("border", 0)
}
//toggle recording of audio
function toggleRecord(){
if(!micIsOn){
mic.start()
micIsOn = true
} else {
mic.stop()
micIsOn = false
}
}
The code above lets me create a sound-visualizer, that taps into the mic of the user, drawing a canvas that displays the level of their sound. Looking like this:
However, when I try to use the library in my Angular directive, I cannot seem to get the draw() method to function as expected. The draw() function does not run continuously like it would outside an Angular directive.
The closest I've gotten to get this to work is by creating a $watch on a variable to track whether the user isRecording. If isRecording is true I would use a setInterval to call draw() continuously. Unfortunately, this appears to an improper usage of the draw() method, since its supposed to execute the code inside it continuously on its own after the first execution.
Angular code:
(function () {
angular.module('icSdkPwp').directive('icAudioRecordingUpload', icAudioRecordingUpload);
function icAudioRecordingUpload($stateSvc, $rS, $utilSvc) {
return {
scope: {
model: '=',
config: '=',
updateState: '='
},
link: function ($s, e, a) {
$s.hasRecording = false;
$s.isRecording = false;
$s.recordingPaused = false;
$s.recordingProcessing = false;
$s.volHistory = []
$s.micIsOn = false
$s.p5mic = null
$s.playButton = null
var gumStream;
var rec;
var input;
var AudioContext = window.AudioContext || window.webkitAudioContext;
var audioContext
$s.startRecording = function(e) {
if($s.recordingProcessing)
return;
var constraints = { audio: true, video:false }
setup()
$s.isRecording = true;
navigator.mediaDevices.getUserMedia(constraints)
.then(function(stream) {
audioContext = new AudioContext();
gumStream = stream;
input = audioContext.createMediaStreamSource(stream);
rec = new Recorder(input,{numChannels:2})
rec.record()
}).catch(function(err) {
$s.isRecording = true;
});
}
var redrawInt = null;
$s.$watch("isRecording", function (n, o, s) {
if(s.isRecording){
redrawInt = setInterval(function(){
draw()
},0);
}
else{
clearInterval(redrawInt);
}
});
function setup(){
createCanvas(400, 150)
$s.p5mic = new p5.AudioIn()
$s.p5mic.start()
$s.micIsOn = true
background(245)
}
function draw(){
stroke(0, 109, 203)
//populate volHistory
if($s.isRecording){
var vol = $s.p5mic.getLevel()
//check to see if array is empty, if it is empty we do not want to push 0 volume
if($s.volHistory.length > 0 && vol > 0){
$s.volHistory.push(vol)
//if recording has started, we can now take in vol
} else if(vol > 0) {
$s.volHistory.push(vol)
}
}
//iterate through volHistory and draw
fill(0, 109, 203)
var barWidth = 2;
var offsetWidth = 5;
var offset = 5;
for(var i = 0; i < $s.volHistory.length; i++){
var barHeight = map($s.volHistory[i], 0, 1, 1, height)
rect(i + offset, (height/2.0) - (barHeight/2.0), barWidth, barHeight, 15);
offset += offsetWidth;
}
//moves wavelength 1 index at a time and account for bar width and offset width
if($s.volHistory.length * (offsetWidth + barWidth) > width){
$s.volHistory.splice(0, 1)
}
//draw vertical line
stroke(250, 30, 100)
// debugger
line($s.volHistory.length + offset, 0, $s.volHistory.length + offset, height)
}
}
};
}
}());
Button that calls startRecording(), initiating the process
<div class="IX_recordControls clearfix">
<div class="rcrow row1">
<div ng-click="recordingProcessing || startRecording($event)"
ng-if="!hasRecording">
</div>
</div>
This gives me a really bizarre canvas, which I suppose is expected since I shouldn't be calling draw() so many times, but I cannot find a way to make it call a single time and run continuously.
This definitely looks like a problem with scope, where the draw() method is unable to execute its own loop.

Tiled map overlap detection not working properly

I am building a tower defence game and I am facing an issue in Phaser with tiled maps.
You see different layers in tiled always have coordinates from (0,0) to (600,600) -> or whatever your tiled width and height is. I have a backgroundLayer and a path. The creeps properly collide with the path.
Now I am trying to change the cursor to a building sprite (for UI when I click on some button and select a tower I want it to turn red when it is on the road or above another tower/creep) and I am using an overlap function for path and buildings.
This overlap function in Phaser checks the rectangle of building sprite and path, but path rectangle is the whole map. The collision works but I only need an overlap. Any ideas how to achieve this? Here is my code.
var RedPlanetGame = RedPlanetGame || {};
var pressed = {
is: false
};
var buildingOverlaps = {
is: false
};
//title screen
RedPlanetGame.Game = function () {
};
RedPlanetGame.Game.prototype = {
create: function create() {
//A door for multyplayer
this.players = [];
this.player = new Player(1, 'Daniel', 300);
this.players.push(this.player);
this.playerInfo = {};
//Tile map
this.map = this.game.add.tilemap('sample2');
this.map.addTilesetImage('32x32_map_tile v3.1 [MARGINLESS]', 'gameTiles');
//background and layers
this.backgroundlayer = this.map.createLayer('backgroundLayer');
this.path = this.map.createLayer('path');
this.map.setCollisionBetween(1, 2000, true, 'backgroundLayer');
this.map.setCollisionBetween(1, 2000, true, 'path');
//objects from tile map
this.spawnCreepsAt = this.map.objects['objectsLayer'][0];
this.destinationForCreeps = this.map.objects['objectsLayer'][1];
//resize world
this.backgroundlayer.resizeWorld();
//this.game.world.setBounds(0, 0, 100, 100);
//groups
this.game.enemies = new UnitsPoolFactory(this.game);
this.game.buildings = this.game.add.group();//TODO: make buildings for each player
this.game.bullets = new BulletsPoolFactory(this.game);
//creep spawning
var _this = this;
const creepYOffset = 15;
setInterval(function () {
_this.game.enemies.factory(_this.spawnCreepsAt.x, _this.spawnCreepsAt.y + creepYOffset, UNIT_TYPES.CREEP1);
}, 1000);
//text and player info
var textX = 150;
var textY = 0;
this.playerInfo.gold = this.game.add.text(textX, textY, 'Player gold: ' + this.player.gold,
{font: "24px Arial", fill: '#FFD700'}
);
//Here is test straight forward code for building towers
this.game.build = this.game.add.group();
this.buildingSprite = this.game.add.sprite(0, 0, 'tower1-1');
this.game.physics.enable(this.buildingSprite, Phaser.Physics.ARCADE);
this.buildingSprite.anchor.setTo(0.5);
this.buildingSprite.scale.setTo(0.5);
this.game.build.add(this.buildingSprite);
console.log(this.path.getBounds());
console.log(this.backgroundlayer.getBounds());
},
update: function update() {
var _this = this;
//Camera follow cursor
if (this.game.input.mousePointer.x > gameHeight - gameHeight / 10) {
this.game.camera.x += 10;
} else if (this.game.input.mousePointer.x <= 100) {
this.game.camera.x -= 10;
}
if (this.game.input.mousePointer.y > gameWidth - gameWidth / 10) {
this.game.camera.y += 10;
} else if (this.game.input.mousePointer.y <= 100) {
this.game.camera.y -= 10;
}
//check for collision between enemy and non-path layer
this.game.physics.arcade.collide(this.game.enemies, this.backgroundlayer);
//checks for collision between bullets and enemies
this.game.physics.arcade.overlap(this.game.bullets, this.game.enemies, function (bullet, enemy) {
enemy.takeHit(bullet, _this.player);
bullet.kill();
}, null, this);
//updates enemies
this.game.enemies.forEach(function (enemy) {
enemy.onUpdate(_this.destinationForCreeps);
});
//updates buildings
this.game.buildings.forEach(function (building) {
building.onUpdate(_this.game.bullets);
});
//on mouse down event
if (this.game.input.activePointer.leftButton.isDown && !pressed.is) {//yo Yoda
//builds new building of type TOWER1
buffer(pressed, 1000);
if (Building.prototype.canBuild(this.player.gold, Tower1.prototype.moneyCost)) {
var poss = this.game.input.mousePointer;
BuildingsFactory(this.game, poss.x, poss.y, this.player, BUILDING_TYPES.TOWER1);
this.player.gold -= Tower1.prototype.moneyCost
} else {
alert('Not enought gold');
}
}
//Here is test straight forward code for building towers
if (Phaser.Rectangle.contains(this.buildingSprite.body, this.game.input.x, this.game.input.y)) {
this.buildingSprite.body.velocity.setTo(0, 0);
}
else {
this.game.physics.arcade.moveToPointer(this.buildingSprite, 700);
}
this.game.physics.arcade.collideGroupVsTilemapLayer(this.game.build, this.path, function (sprite) {
if (!buildingOverlaps.is) {
buffer(buildingOverlaps, 500);
console.log('overlap')
}
}, null, this, true);
},
render: function render() {
this.playerInfo.gold.text = 'Player gold: ' + this.player.gold;
}
};

How do I run an animation when moving to the left or right in JavaScript?

How do I run a sprite animation when pressing the left or right arrow keys in JavaScript? Here's my code:
var avatarX = 0;
var avatarY = 240;
var avatarImage;
var counter = 1;
var XWIDTH = 0;
var WIDTH = 400;
var dx = 5;
var tt;
var gameCanvas;
var context;
var moving;
var animationCounter = 1;
window.addEventListener('keydown', KeyDown);
function setUpGame() { //This is the function that is called from the html document.
gameCanvas = document.getElementById("gameCanvas"); //Declare a new variable & assigns it the id of the CANVAS from the html document.
context=gameCanvas.getContext("2d");
context.font = "18px Iceland";
context.textBaseline = "top";
avatarImage = new Image(); //Declaring a new variable. This is so that we can store the image at a later date.
avatarImage.onload=function(){
// avatarImage is now fully loaded and ready to drawImage
context.drawImage(avatarImage, Math.random() * 100, avatarY);
// start the timer
tt = setInterval(function(){counTer()},1000);
setInterval(handleTick, 25);
}
avatarImage.addEventListener('load', startLoop, false);
avatarImage.src = "img/ships.png"; //Ditto from above.
}
function startLoop() {
console.log("Detecting whether moving to the right is: " + moving);
if(moving == 0) {
gameLoop();
}
}
function gameLoop() {
setTimeout(gameLoop, 100);
handleTick();
}
function KeyDown(evt) {
switch (evt.keyCode) {
case 39: /*Arrow to the right*/
if(avatarX + dx <WIDTH && avatarX + dx >XWIDTH) {
avatarX += dx;
moving = 0;
}
break;
case 37: /*Arrow to the left*/
if(avatarX - dx >XWIDTH) {
avatarX -= dx;
moving = 1;
}
break;
}
}
function counTer() {
if(counter == 60) {
clearInterval(tt);
} else {
counter++;
}
}
function handleTick() {
context.clearRect(0,0,gameCanvas.width,gameCanvas.height);
context.drawImage(avatarImage, 32*animationCounter, 0, 32,32, avatarX, avatarY, 64, 64);
context.fillText("Seconds: " + counter, 5, 5);
context.fillText("1 is Right, 2 is Left, 0 is idle: " + moving, 20, 20);
animationCounter++
if(animationCounter >1) {
animationCounter = 0;
}
}
There are many ways to implement animation. The one i use is pretty easy and looks something like this:
var player = {
x: 0,
y: 0,
width: 50,
height: 100,
sprite: {
column: 0,
row: 0,
height: 50,
width: 100
},
image: PlayerImage,
animation: {
active: true, //Determines if the animation is running or not.
counter: 0,
progress: 0,
sequence: []
}
}
//This functions fires when the left arrow is pressed.
var onLeft = function(){
player.animation.sequence = [{column: 0, row: 0, t: 12}, {column: 1, row: 0, t: 12}, {column: 2, row: 0, t: 12}];
player.animation.active = true;
}
//This functions fires when the right arrow is pressed.
var onRight = function(){
player.animation.sequence = [{column: 0, row: 1, t: 12}, {column: 1, row: 1, t: 12}, {column: 2, row: 1, t: 12}];
player.animation.active = true;
}
//This function fires when no arrow are pressed.
var standingStill = function(){
player.animation.active = false;
}
var handleTick = function(){
//Clear the canvas.
context.canvas.width = context.canvas.width;
//If the animation is active.
if(player.animation.active){
//If the counter >= tick in the sequence. If not, just keep on increasing the counter value.
if(player.animation.counter >= player.animation.sequence[player.animation.progress]){
player.animation.counter = 1;
if(player.animation.progress >= player.animation.sequence.length - 1){
player.animation.progress = 0;
}else{
player.animation.progress++;
}
var currentFrame = player.animation.sequence[player.animation.progress];
//Change player.sprite column and row.(new frame)
player.sprite.column = currentFrame.column;
player.sprite.row = currentFrame.row;
}else{
player.animation.counter++;
}
}
context.drawImage(player.image, player.sprite.column * player.sprite.width, player.sprite.row * player.sprite.height, player.sprite.width, player.sprite.height, player.x, player.y, player.width, player.height)
}
The sequence is an array that contains objects that look like that: {column: 0, row: 0, t: 12} Every object is a frame. The column value is the current x of the sprite, the row is the y of the sprite. The script automatically creates the x and the y value, so all you need to add is value like 0, 1, 3, 5, and so on.(Just which frame it is on either x or y axis.) So for example, if the column is 0 and the row is 0, this is the frame that is in the top-left corner(the first frame). The t value stands for tick, this determines how many ticks there has to happend before the animation goes to the next frame.
Player.sprite also has properties width and height, that's the width and the height of the frame, it is often the same value as the width and height of the player object.
You have to make your own player.animation.sequence in onLeft and onRight function so it animates how you want it to animate.
I hope you understood what i meant. This might seem complicated, but it really isn't and if you don't get it now, don't worry, you'll get it eventually. If you really have difficulties with understanding, just ask.
Edit: First of all i highly recommend using objects to store information about entities. It makes game making much easier and cleaner. Just look at the player object, it's much easier to get the x simply by writing player.x than PlayerX. It looks more professional too. :) And when you have to give a lot of information about your entity you don't have to pass many arguments, you pass the whole object. Example:
//Entity properties stored in separate variable.
function animate(EntityX, EntityY, EntitySpriteX, EntitySpriteY, ...){
var x = EntityX;
//And so on...
}
//Entity stored in an object.
function animate(Entity){
var x = Entity.x;
//And so on...
}
Anyway, back to your question. First, we have to add variables that store information about our sprite.
var avatarSpriteColumn = 0; //Sprite frame on the x axis.
var avatarSpriteRow = 0; //Sprite frame on the y axis.
var avatarSpriteWidth = 50; //The width of a frame.
var avatarSpriteHeight = 100; //The height of a frame.
We also have to add variables that store the information about the animation.
var animationActive = false; //A variable that controls if the animation is 'running'.
var animationCounter = 0; //How many frames(ticks) have passed since the last frame(animation frame) has changed. (I'm not good at describing variables. :P)
var animationProgress = 0; //Current animation frame.
var animationSequence = []; //Array that stores the sequence of animation, as i explained.
Then, in your handleTick function you have to add a code that will animate the sprite. You have to add this code before you draw your entity.
//If the animation is active.
if(animationActive){
//If the counter >= tick in the sequence. If not, just keep on increasing the counter value.
if(animationCounter >= animationSequence[animationProgress]){
animationCounter = 1;
//Reset the progress, so that next time another animation frame shows up.
if(animationProgress >= animationSequence.length - 1){
animationProgress = 0;
}else{
animationProgress++;
}
//Select information about the current animation frame and store it in a variable so it is easier to access.
var currentFrame = animationSequence[animationProgress];
//Change player.sprite column and row.(new frame);
avatarSpriteColumn = currentFrame.column;
avatarSpriteRow = currentFrame.row;
}else{
animationCounter.counter++;
}
}
Ok, now you have a code that animates the sprite, but how do we run it? Well, i see you have a variable called moving. It tells us in what direction the player is moving and if it is moving at all. It looks like you implemented it a little bit wrong. Right now your function that operates the keys looks like this:
function KeyDown(evt) {
switch (evt.keyCode) {
case 39: /*Arrow to the right*/
if(avatarX + dx <WIDTH && avatarX + dx >XWIDTH) {
avatarX += dx;
moving = 0;
}
break;
case 37: /*Arrow to the left*/
if(avatarX - dx >XWIDTH) {
avatarX -= dx;
moving = 1;
}
break;
}
}
The variable is supposed to return 1 if the entity is going to the right, 2 if it is going to the left and 0 if the entity is standing still, right? Right now it shows 0 when the entity is moving to the right and 1 when it is moving to the left. It also doesn't show us if the entity is idle. We have to fix it. Change it to something like this:
function KeyDown(evt) {
switch (evt.keyCode) {
case 39: /*Arrow to the right*/
if(avatarX + dx <WIDTH && avatarX + dx >XWIDTH) {
avatarX += dx;
moving = 1;
}
break;
case 37: /*Arrow to the left*/
if(avatarX - dx >XWIDTH) {
avatarX -= dx;
moving = 2;
}
break;
default:
moving = 0;
}
}
Ok, now we have to add this code to the handleTick function. This code starts the animation and changes the sequence.:
if(moving == 1){ //Moving in the right direction.
animationSequence = []; //Animation of moving in the right direction. Change the sequence to your own.
animationActive = true; //Run the animation.
}else if(moving == 2){ //Moving to the left.
animationSequence = []; //Animation of moving to the left. Change the sequence to your own.
animationActive = true; //Run the animation.
}else{
animationActive = false; //Stops the animation, but the last frame stays.
/*
Alternatively, if you want a separate frame or animation that is animating when the entity is standing, you run this code.
animationSequence = []; // Your sequence. If you want a single frame, with no animation just add one frame to the sequence.
animationActive = true;
*/
}
Now, the last thing we have to do is to draw the entity. In your case, this will look something like this:
context.drawImage(avatarImage, avatarSpriteColumn * avatarSpriteWidth, avatarSpriteRow * avatarSpriteHeight, avatarWidth, avatarHeight, avatarX, avatarY, 64, 64);
In the end your whole code will look something like this:
var avatarX = 0;
var avatarY = 240;
var avatarImage;
var counter = 1;
var XWIDTH = 0;
var WIDTH = 400;
var dx = 5;
var tt;
var gameCanvas;
var context;
var moving;
var animationCounter = 1;
var avatarSpriteColumn = 0; //Sprite frame on the x axis.
var avatarSpriteRow = 0; //Sprite frame on the y axis.
var avatarSpriteWidth = 50; //The width of a frame.
var avatarSpriteHeight = 100; //The height of a frame.
var animationActive = false; //A variable that controls if the animation is 'running'.
var animationCounter = 0; //How many frames(ticks) have passed since the last frame(animation frame) has changed. (I'm not good at describing variables. :P)
var animationProgress = 0; //Current animation frame.
var animationSequence = []; //Array that stores the sequence of animation, as i explained.
window.addEventListener('keydown', KeyDown);
function setUpGame() { //This is the function that is called from the html document.
gameCanvas = document.getElementById("gameCanvas"); //Declare a new variable & assigns it the id of the CANVAS from the html document.
context=gameCanvas.getContext("2d");
context.font = "18px Iceland";
context.textBaseline = "top";
avatarImage = new Image(); //Declaring a new variable. This is so that we can store the image at a later date.
avatarImage.onload=function(){
// avatarImage is now fully loaded and ready to drawImage
context.drawImage(avatarImage, Math.random() * 100, avatarY);
// start the timer
tt = setInterval(function(){counTer()},1000);
setInterval(handleTick, 25);
}
avatarImage.addEventListener('load', startLoop, false);
avatarImage.src = "img/ships.png"; //Ditto from above.
}
function startLoop() {
console.log("Detecting whether moving to the right is: " + moving);
if(moving == 0) {
gameLoop();
}
}
function gameLoop() {
setTimeout(gameLoop, 100);
handleTick();
}
function KeyDown(evt) {
switch (evt.keyCode) {
case 39: /*Arrow to the right*/
if(avatarX + dx <WIDTH && avatarX + dx >XWIDTH) {
avatarX += dx;
moving = 1;
}
break;
case 37: /*Arrow to the left*/
if(avatarX - dx >XWIDTH) {
avatarX -= dx;
moving = 2;
}
break;
default:
moving = 0;
}
}
function counTer() {
if(counter == 60) {
clearInterval(tt);
} else {
counter++;
}
}
function handleTick() {
context.clearRect(0,0,gameCanvas.width,gameCanvas.height);
if(moving == 1){ //Moving in the right direction.
animationSequence = []; //Animation of moving in the right direction. Change the sequence to your own.
animationActive = true; //Run the animation.
}else if(moving == 2){ //Moving to the left.
animationSequence = []; //Animation of moving to the left. Change the sequence to your own.
animationActive = true; //Run the animation.
}else{
animationActive = false; //Stops the animation, but the last frame stays.
/*
Alternatively, if you want a separate frame or animation that is animating when the entity is standing, you run this code.
animationSequence = []; // Your sequence. If you want a single frame, with no animation just add one frame to the sequence.
animationActive = true;
*/
}
//If the animation is active.
if(animationActive){
//If the counter >= tick in the sequence. If not, just keep on increasing the counter value.
if(animationCounter >= animationSequence[animationProgress]){
animationCounter = 1;
//Reset the progress, so that next time another animation frame shows up.
if(animationProgress >= animationSequence.length - 1){
animationProgress = 0;
}else{
animationProgress++;
}
//Select information about the current animation frame and store it in a variable so it is easier to access.
var currentFrame = animationSequence[animationProgress];
//Change player.sprite column and row.(new frame);
avatarSpriteColumn = currentFrame.column;
avatarSpriteRow = currentFrame.row;
}else{
animationCounter.counter++;
}
}
context.drawImage(avatarImage, avatarSpriteColumn * avatarSpriteWidth, avatarSpriteRow * avatarSpriteHeight, avatarWidth, avatarHeight, avatarX, avatarY, 64, 64);
context.fillText("Seconds: " + counter, 5, 5);
context.fillText("1 is Right, 2 is Left, 0 is idle: " + moving, 20, 20);
}
The only thing you have to do right now is to make your own animationSequences and check if it works, let me know if you have any problems with that.
Of course, the code i am using is more complicated and has more "abilities" and is easier to use(the code behind is more complicated), but hopefully this will help you.
I must also apoligize for making this thing seem so complicated, when it's not. I am bad at explaining.

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