I am making this background for a page drawing random lines. The lines are being drawn and it looks as it was supposed to but when I look into the console I get about ~10 errors every second. It says it cannot read startX and starY. When I change it to x and why it does not draw the lines anymore.
var sandbox = document.getElementById('sandbox');
ctx = sandbox.getContext('2d');
var referencePoint = function(x, y) {
this.startX = x;
this.startY = y;
};
const progressPoints = [];
for (let i = 0; i < 15; i++) {
let x = Math.floor(Math.random() * sandbox.width);
let y = Math.floor(Math.random() * sandbox.height);
progressPoints.push(new referencePoint(x, y));
};
ctx.strokeStyle= "grey";
ctx.moveTo(progressPoints[0].x, progressPoints[0].y);
It supposedly cannot read those startX and startY:
var counter = 1,
interval = setInterval(function() {
var point = progressPoints[counter];
ctx.lineTo(point.startX, point.startY);
//alert(point.startX, point.startY)
ctx.stroke();
if(counter >= progressPoints.lenght){
clearInterval(interval);
};
counter++
}, 140);
(function() {
var contentBox = $('div.content-box'),
activeContent = contentBox.find('div.active-content'),
pageTransitionOverlay = contentBox.find('div.page-transition-overlay'),
navBtn = $('a.nav-btn'),
hiddenContent = $('div.hidden-content');
navBtn.on('click', function(e) {
var self = $(this),
moveToActive = hiddenContent.find('div.' + self.data('target-class'));
contentBox.addClass('transitionEffect');
pageTransitionOverlay.fadeIn(300, function() {
// Change content
self.closest('div.content-wrapper').appendTo(hiddenContent);
moveToActive.appendTo(activeContent);
// Transition transitionEffect
contentBox.removeClass('transitionEffect');
pageTransitionOverlay.fadeOut(300);
});
e.preventDefault();
});
})();
So it seems that length is too much, try 1 less
if (counter >= progressPoints.length - 1) { ... }
var sandbox = document.getElementById('sandbox');
ctx = sandbox.getContext('2d');
var referencePoint = function(x, y) {
this.startX = x;
this.startY = y;
};
const progressPoints = [];
for (let i = 0; i < 15; i++) {
let x = Math.floor(Math.random() * sandbox.width);
let y = Math.floor(Math.random() * sandbox.height);
progressPoints.push(new referencePoint(x, y));
};
ctx.strokeStyle = "grey";
ctx.moveTo(progressPoints[0].x, progressPoints[0].y);
var counter = 1,
interval = setInterval(function() {
var point = progressPoints[counter];
ctx.lineTo(point.startX, point.startY);
//alert(point.startX, point.startY)
ctx.stroke();
if (counter >= progressPoints.length - 1) {
clearInterval(interval);
};
counter++
}, 140);
(function() {
var contentBox = $('div.content-box'),
activeContent = contentBox.find('div.active-content'),
pageTransitionOverlay = contentBox.find('div.page-transition-overlay'),
navBtn = $('a.nav-btn'),
hiddenContent = $('div.hidden-content');
navBtn.on('click', function(e) {
var self = $(this),
moveToActive = hiddenContent.find('div.' + self.data('target-class'));
contentBox.addClass('transitionEffect');
pageTransitionOverlay.fadeIn(300, function() {
// Change content
self.closest('div.content-wrapper').appendTo(hiddenContent);
moveToActive.appendTo(activeContent);
// Transition transitionEffect
contentBox.removeClass('transitionEffect');
pageTransitionOverlay.fadeOut(300);
});
e.preventDefault();
});
})();
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.2.4/jquery.min.js"></script>
<canvas id="sandbox"></canvas>
Is there any solution for this? We need parallel edges, but not that way how ParallelEdgeLayout makes that.
I tried to rewrite the layout function of parallel layout to move the edges, but edges has no usable geometry: x, y, width, height are 0. There I couldn't move them anywhere.
Tried to use setStyle, but did not do anything:
var s = model.getStyle(parallels[i]) + 'entryX='+x0+';exitX='+x0+';'
console.log(s)
model.setStyle(parallels[i], s);
Oh my God! Here is a solution. Not the dream edges, but almost... Maybe there are more beautiful solutions (post one), but this is mine for showing real parallel edges:
var spx = 1 / 22;
var spy = 1 / 8;
var x0 = 0.5;
var y0 = 0.5;
for (var i = 0; i < parallels.length; i++) {
var source = view.getVisibleTerminal(parallels[i], true);
var target = view.getVisibleTerminal(parallels[i], false);
var src = model.getGeometry(source);
var trg = model.getGeometry(target);
var srcx = src.x, srcy = src.y, trgx = trg.x, trgy = trg.y;
if (parallels[i].getParent() != source.getParent()) {
var pGeo = model.getGeometry(source.getParent());
srcx = src.x + pGeo.x;
srcy = src.y + pGeo.y;
}
if (parallels[i].getParent() != target.getParent()) {
var pGeo = model.getGeometry(target.getParent());
trgx = trg.x + pGeo.x;
trgy = trg.y + pGeo.y;
}
var scx = srcx + src.width; // source element right
var scy = srcy + src.height; // source element bottom
var tcx = trgx + trg.width; // target element right
var tcy = trgy + trg.height; // target element bottom
var dx = tcx - scx; // len x
var dy = tcy - scy; // len y
var sourcePointX, sourcePointY, targetPointX, targetPointY;
if (Math.abs(dx) > Math.abs(dy)) { // horizontal
sourcePointY = y0;
targetPointY = y0;
if (srcx < trgx) { // left to right
sourcePointX = 1;
targetPointX = 0;
} else {
sourcePointX = 0;
targetPointX = 1;
}
} else {
sourcePointX = x0;
targetPointX = x0;
if (srcy < trgy) { // top to bottom
sourcePointY = 1;
targetPointY = 0;
} else {
sourcePointY = 0;
targetPointY = 1;
}
}
this.graph.setConnectionConstraint(parallels[i], parallels[i].source, true, new mxConnectionConstraint(new mxPoint(sourcePointX, sourcePointY), true));
this.graph.setConnectionConstraint(parallels[i], parallels[i].target, false, new mxConnectionConstraint(new mxPoint(targetPointX, targetPointY), true));
if (i % 2) {
x0 += spx * (i + 1);
y0 += spy * (i + 1);
} else {
x0 -= spx * (i + 1);
y0 -= spy * (i + 1);
}
}
Closed. This question needs debugging details. It is not currently accepting answers.
Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
Closed 6 years ago.
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Fist time i am using phaser.io, i am repeating background and also loading other thing in update function but after few second later my game is slowing time . it look like background is not moving more. Please have a look of my code and help me in for sort out this problem. Or please give any idea to change background repeatedly without changing other thing.
I have some code indentation problem sorry for that but please try to manage and help me.
Game.js
var scoreTxt, score, speed, scoreTextValue, ques_label, ques_label_pizza, scoreTextKey, timerTextValue, timerTextKey, textStyle_Key, textStyle_Value, anscloud, astroid1, astroid2, astroid3, astroid4;
/*var gameType;*/ //Pizza or Noun
var bullets, quesTextValue, ansTextValue, sprite;
var fireRate = 100;
var nextFire = 0;
var xAxis = [];
var yAxis = [];
var tempQues = [];
var tempAns = [];
var result = [];
var answear = [];
var ques = [];
var astroidContains = [];
var astroidContainsText = []; //['right', 'wrong', 'wrong', 'wrong']
var astroid, spaceShip, quesbar, diamond, randomAnsPosition;
var s1Copy;
var cloudContains = []; //['noun', 'pronoun', 'pronoun']
var QbarContainsQue = [];
var ans,rightans;
var isAnswerCorrect = false;
var allowClick = false;
var spaceShipXAxis = 40, loader1Width = 85, loader2Width = 70;
var bar, loader1, loader2, timer, timerSprite, timerSpriteCount = 0;
var timerCounter = 45; //timer counter will be of 45 seconds.
//var timerCounter_ = 100; //timer counter will be of 45 seconds.
var questCounter = 0; //question counter no. of question played.
var maxQuest = 10;//max questions will be displayed is 10.
var diamondTextColor = "#8D4FA8";
var defTextColor = "#5BEFFE";
var ansTextColor = "#9E13DA";
var errTextColor = '#FF0000';
var corrTextColor = '#228B22';
var corr_ans_fst;
var corr_ans_sec;
var fun_bckg, randQues;
var wrong_ans;
var barre1_x = 150;
var barre1_y = 115;
var healthValue = 100;
var x_loader = 180;
var check =0;
var setAns = [];
var setOne = [['12+16=','28'], ['15+11=','26'], ['16+22=','38'], ['13+14=','27'], ['15+24=','39'], ['14+12=','26'], ['10+17=','27'], ['11+11=','22'],
['13+15=','28'], ['12+21=','33'], ['24+13=','37'], ['33+21=','54'], ['40+18=','58'], ['34+31=','65'], ['25+42=','67'], ['22+15=','37'],
['24+12=','36'], ['20+15=','35'], ['25+14=','39'], ['21+21=','42'], ['41+25=','66'], ['53+24=','77'], ['35+31=','66'], ['62+37=','99'],
['54+35=','89']];
var setTwo = [['15+18=','33'], ['17+17=','34'], ['13+19=','32'], ['18+14=','32'], ['15+27=','42'], ['18+17=','35'], ['27+29=','56'], ['23+28=','51'],
['36+37=','73'], ['45+25=','70'], ['46+45=','91'], ['38+57=','95'], ['49+43=','92'], ['37+53=','90'], ['48+33=','81']];
var Game = {
preload : function() {
// Load the needed image for this(play) game screen.
//load the menu screen
this.load.image('menu', './assets/images/menu.png');
// Here we load all the needed resources for the level.
// background image screen
this.load.image('playgame', './assets/images/back.png');
// globe image screen
this.load.image('playgame', './assets/images/back.png');
// win image screen
//this.load.image('win', './assets/images/win.png');
// spaceship image screen
this.load.image('spaceship', './assets/images/spaceship.png');
// Question bar image screen
this.load.image('quesbar', './assets/images/quesbar.png');
// Diamond image screen
this.load.image('diamond', './assets/images/diamond.png');
// Astroid image screen
this.load.image('astroid1', 'assets/images/asteroid1.png');
this.load.image('astroid2', 'assets/images/asteroid2.png');
this.load.image('astroid3', 'assets/images/asteroid3.png');
this.load.image('astroid4', 'assets/images/asteroid4.png');
// Loader image screen
this.load.image('loaderbck', 'assets/images/loaderbck.png');
this.load.image('loader1', 'assets/images/loader1.png');
this.load.image('loader2', 'assets/images/loader2.png');
//Load the bullet
this.load.image('bullet', 'assets/images/bullet.png');
},
create : function() {
// By setting up global variables in the create function, we initialise them on game start.
// We need them to be globally available so that the update function can alter them.
textStyle_Value = { font: "bold 20px Segoe UI", fill: defTextColor, align: "center" };
textStyleAns = { font: "bold 22px 'Comic Sans MS', 'Comic Sans'", fill: ansTextColor, wordWrap: true, wordWrapWidth: 10, align: "center"};
textStyleQues = { font: "bold 20px 'Comic Sans MS', 'Comic Sans'", fill: defTextColor, wordWrap: true, wordWrapWidth: 10, align: "center"};
sprite = game.add.sprite(310, 485, 'spaceship');
sprite.anchor.set(0.5);
// Loading backround image
this.playBackground();
this.playBackground1();
// Additional Sprites, like cloud
this.addSprites();
// Loading spaceship image
//this.spaceship();
// Loading questionbar image
this.questionbar();
// Call fun. for ques
this.comeQus();
// csll fun. for place astroid
// this.astroid();
// call fun. for Ans
this.generateQues();
this.generateAns();
// Loading Diamond image
this.diamond();
// Start timer
this.startTimer();
// Set timer.
this.setTimer();
this.initLoader();
},
update: function() {
// The update function is called constantly at a high rate (somewhere around 60fps),
// updating the game field every time - also destroying previous objects and creating new.
// Our bullet group
//bullets.destroy();
sprite.destroy();
bullets = game.add.group();
bullets.enableBody = true;
bullets.physicsBodyType = Phaser.Physics.ARCADE;
bullets.createMultiple(200, 'bullet', 100, false);
bullets.setAll('anchor.x',0);
bullets.setAll('anchor.y', 0.9);
bullets.setAll('outOfBoundsKill', true);
bullets.setAll('checkWorldBounds', true);
//Repeating background..
if(playgame != null && playgame.body.y > 600) {
playgame.destroy();
this.playBackground();
}
if(playgame1.body.y > 0) {
playgame1.destroy();
this.playBackground1();
this.initLoader();
}
if(astroid1 != undefined) astroid1.destroy();
if(astroid2 != undefined) astroid2.destroy();
if(astroid3 != undefined) astroid3.destroy();
if(astroid4 != undefined) astroid4.destroy();
this.addSprites();
//timerTextValue.text = "00:" + timerCounter;
this.initLoader();
//destroing old diamond obj and creating new while change background
//diamond.destroy();
this.diamond();
//destroing old questionbar obj and creating new while change background
quesbar.destroy();
this.questionbar();
//Call comeQus, comeAns for show ques and ans at every background change
// quesTextValue.destroy();
if(quesTextValue != undefined) quesTextValue.destroy();
this.comeQus();
//ansTextValue.destroy();
if(ansTextValue != undefined) ansTextValue.destroy();
this.comeAns();
if (game.input.activePointer.isDown) {
this.fire();
}
allowClick = true;
},
playBackground: function() {
// console.log("playBackground called");
playgame = this.add.sprite(0, 0, 'playgame', 5);
playgame.scale.set(1);
playgame.smoothed = false;
anim_playgame = playgame.animations.add('walk');
anim_playgame.play(10, true);
this.physics.enable(playgame, Phaser.Physics.ARCADE);
playgame.body.velocity.y = 50;
},
playBackground1: function() {
//console.log("playBackground1 called");
//Second background..
playgame1 = this.add.sprite(0, -600, 'playgame', 5);
playgame1.scale.set(1);
playgame1.smoothed = false;
anim_playgame1 = playgame1.animations.add('walk');
anim_playgame1.play(10, true);
this.physics.enable(playgame1, Phaser.Physics.ARCADE);
playgame1.body.velocity.y = 50;
},
questionbar: function() {
quesbar = game.add.image(10, 530, 'quesbar');
},
diamond: function() {
diamond = game.add.image(680, 20, 'diamond');
},
addSprites: function() {
// loading answer cloud
astroid1 = this.add.button(30, 90, 'astroid1', this.astroidClicked, this);
astroid2 = this.add.button(220, 30, 'astroid2', this.astroidClicked, this);
astroid3 = this.add.button(400, 40, 'astroid3', this.astroidClicked, this);
astroid4 = this.add.button(600, 90, 'astroid4', this.astroidClicked, this);
},
inCorrectAnswerHit: function(index) {
allowClick = false;
isAnswerCorrect = false;
//this.playFx('wrong_ans');
for(i=0; i<=3; i++) {
if(cloudContains[i] == "right") {
//cloudContainsText[i].fill = corrTextColor;
console.log("right ans hit");
break;
}
}
},
checkAnswer: function(index) {
// If clicked Ans is right so astroid will destroy.
if(astroidContainsText[index] == "wrong") {
//Here collization function will call
isAnswerCorrect = true;
}
// If clicked word is noun (correct answer) and obstacle is redbird or blackbird - the dude will slide.
else {
this.inCorrectAnswerHit(index);
}
},
generateQues: function(){
var que;
// Generating random questions from given list of ques - setOne.
s1Copy = setOne.slice();
//var result = [];
for (var i = 0; i < 3; i++) {result.push(s1Copy.splice(~~(Math.random()*s1Copy.length),1)[0]);}
s1Copy.push(...setTwo);
for (var i = 0; i < 7; i++) {result.push(s1Copy.splice(~~(Math.random()*s1Copy.length),1)[0]);}
result.toString();
for(var i = 0; i < result.length ; i++ ) {
que = result[i];
ques.push(que[0]);
ques.toString();
//console.log(ques);
answear.push(que[1]);
}
},
comeQus: function() {
quesTextValue = this.add.text(50,541, ques[0],textStyleQues);
this.generateQues();
//tempNoun = [];
},
generateAns: function() {
//Generate two digitd rendom no. and create an array of ans setAns[]
// Add digitd in array
for(var i = 0; i < 3 ; i++) {
var digit = Math.floor(Math.random() * 90 + 10);
//console.log(digit);
setAns.push(digit);
astroidContains[i] = "wrong";
}
console.log(astroidContains);
//console.log(answear);
setAns.push(answear[0]);
astroidContains[i] = "right";
console.log(astroidContains);
shuffle(setAns);
randomAnsPosition = [0, 1, 2, 3];
shuffle(randomAnsPosition);
},
comeAns: function() {
// x and y axis param for placing Answers text.
xAxis = [ 85, 255, 453, 675];
yAxis = [130, 48, 60, 120];
// console.log(setAns);
// Set Answers from above array of Ans - setAns.
for (var i = 0; i < setAns.length; i++) {
var ans = setAns[i];
//console.log(ans);
ansTextValue = this.add.text(xAxis[randomAnsPosition[i]], yAxis[randomAnsPosition[i]], ans, textStyleAns);
astroidContainsText[i] = ansTextValue;
//console.log(ansTextValue.text);
}
},
// Observing which cloud is clicked and checking answer accordingly.
astroidClicked: function() {
// alert("HEllo called");
if(!allowClick) {
return;
}
if(astroid1.game.input._x > 85 && astroid1.game.input._x < 130) {
console.log("cloud_1_Clicked, Clicked:" + astroidContains[0]);
this.checkAnswer(0);
}
else if(astroid2.game.input._x > 255 && astroid2.game.input._x < 48) {
//console.log("cloud_2_Clicked, Clicked:" + astroidContains[1]);
this.checkAnswer(1);
}
else if(astroid3.game.input._x > 453 && astroid3.game.input._x < 60) {
//console.log("cloud_3_Clicked, Clicked:" + astroidContains[2]);
this.checkAnswer(2);
}
else if(astroid4.game.input._x > 675 && astroid4.game.input._x < 120) {
//console.log("cloud_3_Clicked, Clicked:" + astroidContains[2]);
this.checkAnswer(3);
}
allowClick = false;
},
startTimer: function() {
// Create our Timer
timer = game.time.create(false);
// Set a TimerEvent to occur after 1 seconds
timer.loop(1000, this.updateCounter, this);
// Set a TimerEvent to occur after 1 seconds
// timer.loop(100, this.timerStripeChange, this);
// Start the timer running - this is important!
// It won't start automatically, allowing you to hook it to button events and the like.
timer.start();
},
gameOver: function() {
//Gameover screen
this.state.start('Game_Over', true, false);
},
initLoader: function() {
//*******Loader
check +=1;
var bmd = this.game.add.bitmapData(185, 30);
bmd.ctx.beginPath();
bmd.ctx.rect(0, 0, 185, 36);
bmd.ctx.fillStyle = '#00685e';
bmd.ctx.fill();
var bglife = this.game.add.sprite(100, 38, bmd);
bglife.anchor.set(0.5);
if(check != 0)
bmd = this.game.add.bitmapData(x_loader-4, 26);
else
bmd = this.game.add.bitmapData(x_loader, 26);
bmd.ctx.beginPath();
bmd.ctx.rect(0, 0, 180, 26);
if(x_loader <= 120 && x_loader > 60) {
bmd.ctx.fillStyle = "#FFFF00";
} else if(x_loader <= 60) {
bmd.ctx.fillStyle = "#EA0B1E";
} else {
bmd.ctx.fillStyle = '#00f910';
}
bmd.ctx.fill();
this.widthLife = new Phaser.Rectangle(0, 0, bmd.width, bmd.height);
this.totalLife = bmd.width;
//x_loader = ;
/*console.log(this.totalLife);
console.log(this.widthLife);*/
this.life = this.game.add.sprite(93 - bglife.width/2 + 10, 38, bmd);
this.life.anchor.y = 0.5;
this.life.cropEnabled = true;
this.life.crop(this.widthLife);
// this.game.time.events.loop(1450, this.cropLife, this);
},
updateCounter: function() {
if(timerCounter <= 0) {
this.gameOver();
return;
}
timerCounter--;
if(this.widthLife.width <= 0){
this.widthLife.width = this.totalLife;
}
else{
//this.game.add.tween(this.widthLife).to( { width: (x_loader - 4) }, 200, Phaser.Easing.Linear.None, true);
//console.log(this.widthLife.width);
this.widthLife.width = x_loader - 4;
x_loader = this.widthLife.width;
}
},
fire: function () {
if (game.time.now > nextFire && bullets.countDead() > 0)
{
nextFire = game.time.now + fireRate;
var bullet = bullets.getFirstDead();
bullet.reset(sprite.x - 80, sprite.y - 80);
game.physics.arcade.moveToPointer(bullet, 300);
}
}
}
/**
* Shuffles array in place.
* #param {Array} a items The array containing the items.
*/
function shuffle(a) {
var j, x, i;
for (i = a.length; i; i -= 1) {
j = Math.floor(Math.random() * i);
x = a[i - 1];
a[i - 1] = a[j];
a[j] = x;
}
}
As already noted it is a lot of code.
So far what I can see, is a memory leak in the update() function:
bullets = game.add.group();
bullets.enableBody = true;
bullets.physicsBodyType = Phaser.Physics.ARCADE;
bullets.createMultiple(200, 'bullet', 100, false);
bullets.setAll('anchor.x',0);
bullets.setAll('anchor.y', 0.9);
bullets.setAll('outOfBoundsKill', true);
bullets.setAll('checkWorldBounds', true);
With that you are constantly creating new bullets. Put that in the create() function and try again.
I need to create an animation of dropping box, which supposed to bounce 10 times when it reaches a certain Y point on canvas, each time twice lower that the previous. So I have the animation of the dropping box, but I can't make the bounce work. Here are the functions that I wrote:
function dropBox(y, width, height) {
var img_box = new Image();
img_box.src = 'images/gift_box_small.png';
var box_y_pos = y;
if(y==0)
box_y_pos = y-img_box.naturalHeight;
img_box.onload = function(){
ctx_overlay.save();
ctx_overlay.clearRect(0,0,width,height);
ctx_overlay.drawImage(img_box, (width/2)-(img_box.naturalWidth/2), box_y_pos);
ctx_overlay.restore();
}
box_y_pos += 3;
var box_bottom_position = box_y_pos - img_box.naturalHeight;
if(box_y_pos+img_box.naturalHeight<height-25)
var loopTimer = setTimeout(function() {dropBox(box_y_pos, width, height)},24);
else
bounceBox(img_box, box_y_pos, box_y_pos, (height/2)-(img_box.naturalHeight/2), "up");
}
function bounceBox(img, img_final_pos, y, midway_pos, direction){
var midway = midway_pos;
var direction = direction;
var img_y_pos = y;
img.onload = function(){
ctx_overlay.save();
ctx_overlay.clearRect(0,0,docWidth,docHeight);
ctx_overlay.drawImage(img, (docWidth/2)-(img.naturalWidth/2), img_y_pos);
ctx_overlay.restore();
}
for(var i = 0; i < 10; i++){
if(direction=="up"){
//going up
if(img_y_pos>midway_){
img_y_pos -= 3;
var loopTimer = setTimeout(function() {bounceBox(img, img_final_pos, img_y_pos, midway_pos, "up")},24);
} else {
img_y_pos += 3;
midway = Math.floor(midway /= 2);
if(midway%2>0)
midway += 1;
var loopTimer = setTimeout(function() {bounceBox(img, img_final_pos, img_y_pos, midway_pos, "down")},24);
}
} else {
//going down
if(img_y_pos < img_final_pos){
img_y_pos += 3;
var loopTimer = setTimeout(function() {bounceBox(img, img_final_pos, img_y_pos, midway_pos, "down")},24);
}
}
}
}
JSFiddle: http://jsfiddle.net/n2derqgw/3/
Why isn't it working and how can I make it work?
To avoid getting a headache, you've better handle the animation within a single function called with a setInterval.
And keep all animation-related data in one object.
So the code below does not exactly what you want, but should get you started :
http://jsfiddle.net/n2derqgw/4/
Setup :
var canvas_overlay, ctx_overlay, docWidth, docHeight;
var img_box = new Image();
img_box.src = 'http://corkeynet.com/test/images/gift_box_small.png';
var mustBeReadyCount = 2; // must load image and window
img_box.onload = launchWhenReady;
window.onload = launchWhenReady;
var animationStep = '';
var boxAnimationData = {
animationStep: '',
y: 0,
maxY: 0,
bounceCount: 6,
direction: -1,
bounceHeight: 0
};
function launchWhenReady() {
mustBeReadyCount--;
if (mustBeReadyCount) return;
docWidth = window.innerWidth;
docHeight = window.innerHeight;
canvas_overlay = document.getElementById('canvas_overlay');
ctx_overlay = canvas_overlay.getContext('2d');
resizeCanvas(docWidth, docHeight);
boxAnimationData.animationStep = 'falling';
boxAnimationData.bounceHeight = docHeight / 2 - img_box.height;
setInterval(animateBox, 30);
};
More interesting code is here :
function animateBox() {
if (boxAnimationData.animationStep == 'falling') dropBox();
else if (boxAnimationData.animationStep == 'bouncing') bounceBox();
}
function dropBox() {
ctx_overlay.clearRect(0, 0, docWidth, docHeight);
boxAnimationData.y += 3;
if (boxAnimationData.y + img_box.height > docHeight) {
boxAnimationData.animationStep = 'bouncing';
}
ctx_overlay.drawImage(img_box, (docWidth / 2) - (img_box.width / 2), boxAnimationData.y);
}
function bounceBox() {
ctx_overlay.clearRect(0, 0, docWidth, docHeight);
boxAnimationData.y += boxAnimationData.direction * 3;
if (boxAnimationData.y + img_box.height > docHeight) {
// reached floor ? swap direction
boxAnimationData.direction *= -1;
// and reduce jump height
boxAnimationData.bounceHeight *= 3 / 2;
boxAnimationData.bounceCount--;
if (!boxAnimationData.bounceCount) boxAnimationData.animationStep = '';
} else if (boxAnimationData.y < boxAnimationData.bounceHeight) {
boxAnimationData.direction *= -1;
}
ctx_overlay.drawImage(img_box, (docWidth / 2) - (img_box.width / 2), boxAnimationData.y);
}