A new feature of HTML5, allowing Javascript apps to have a drawing surface in the browser.

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1answer
18 views

creating an html5 game

I am working on a really simple online version of the parachute shooters game that was preprogrammed on old iPods. I'm pretty new to game development and so at first I tried to build the whole game ...
2
votes
1answer
31 views

How do I use createPattern with a spritesheet?

Say that I have a spritesheet like this And I want to use the dirt tile at (1, 1). I know that I can repeat an entire image using createPattern but how do I create the pattern from just the tile ...
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1answer
56 views

collision detection algorithm issue

here is the jsfiddle i am working on so far : http://jsfiddle.net/TLYZS/ if you debug the code and check the collision function you can see that the collision is working fine when the user overlap ...
0
votes
1answer
37 views

Dealing with multiple animation state in one sprite sheet image using html5 canvas

I am recently creating a Game using html5 canvas .The player have multiple state it can walk jump kick and push and multiple other states my question is simple but after some deep research i couldn't ...
1
vote
1answer
47 views

JavaScript: Rotating a canvas around its center for a 2D sidescroller

I've been making a 2D sidescrolling game using JavaScript and HTML. The game is set in space, where the player character can fly around (Up, Down, Left and Right keys) and rotate the world around him ...
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0answers
34 views

HTML5 Canvas: Get rect coords after rotation (relative to screen)

update: function(delta) { for (var i = 0; i < this.bullets.length; i++) { this.bullets[i].velocity = this.bullets[i].speed * delta; this.bullets[i].contextX += ...
2
votes
1answer
186 views

HTML5 - Dynamic canvas grid for scrolling a big map

I've been working on different scrolling algorithms for my JS-based game. My main problem is that I need to draw a huge map and also have it scroll smoothly. I've made a few attempts and while they're ...
4
votes
0answers
144 views

How to do a genetic algorithm's chromosome which controls movements

First I would like to inform you that I'm french and 15 so my english is not very good. I've read some articles about genetic algorithms (GA) and since I discovered the HTML5's canvas element, I can ...
2
votes
0answers
331 views

Poor performance in android when running APK, runs fine in browser

I have created a small game project in HTML5 using Phaser engine (tried both 1.1.5 and 1.1.6). Then to port it to mobile platform, used Phonegap/Cordova for Windows Phone 8, Android and iOS. In my ...
3
votes
2answers
118 views

HTML5 game fps render lag

I am currently creating a flappyBird-like HTML5 game using Proccessing.js You can see current work here: http://files.tips4design.com/flappySlothRelease/ The problem is that even though the FPS is ...
0
votes
1answer
68 views

What's the best way to time a character AI movement on android/java?

I'm creating an android game and I'm trying to figure out the best way to time a character position change, something like this: public void move() { //this.posX += 5; this.posY += 5; if ...
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0answers
65 views

Make bitmap moviment on android canvas using timer or handler/Runnable/postDelayed

Im trying to to move enemies on a android canvas, i have to update its x and y position every x time (run enemy.move() every x time). I got 2 problems: Currently im implementing my canvas redraw ...
0
votes
1answer
146 views

2D to 3D perlin noise, I'm not sure I get it

I've been using 2d perlin noise to generate height maps for a little isometric terrain experiment. The noise value is directly related to the z-layer a tile will appear in: Math.floor(noise * 10). ...
0
votes
1answer
84 views

How do I make a sprite blink on an HTML5 canvas?

I'm thinking of the flashing effect many games have when a character gets hit and takes damage. Something like overlaying a lighter color on visible sprite pixels for a second.
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vote
2answers
82 views

Calculate tile ID on a Reus style world with canvas context.arc()

I need a bit of math help for my game. I'm using Javascript and the Canvas tag to create a circular world, think God Finger, and Reus. The current version of my game is here: ...
0
votes
1answer
35 views

Update function in html5 canvas game isn't working properly [closed]

Jsfiddle : http://jsfiddle.net/seekpunk/6eeKH/15/ the code : if (this.collection.length > 0) { if (((this.collection[0].blockX + this.collection[0].blockW) >= cw) || ...
2
votes
3answers
145 views

Is it more efficient to encode rotation in a spritesheet or rotate at runtime?

I'm developing a game with JavaScript and HTML5 and I'm wondering about the performance implications of sprite rotations. There are two ways that I know to rotate a sprite: Rotate the actual sprite ...
0
votes
0answers
41 views

What would be a good way to scroll a large html canvas (that contains little repetition if any)

What would be a good way to scroll the content of a huge html5 canvas so that the scroll is crisp and smooth, and memory consumption (and cpu load or battery consumption) is also reasonable? any ...
1
vote
3answers
93 views

Canvas setTransform function clarification

I'm currently building some kind of fake-3D dungeon, and I'm facing some difficulties understanding the behavior of the setTransform() function. Here's my simplified code: var can = ...
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0answers
18 views

Clicking on a canvas getting polygon [duplicate]

I'm using Canvas to create polygons like this: http://bl.ocks.org/mbostock/6675193 I want each of those polygons to represent a clickable province. How do I know which province is clicked when the ...
3
votes
1answer
122 views

How can I detect mouse events on sprites in a canvas?

I'm making an HTML 5 game. I want mouse clicks on sprites drawn in a canvas element cause events that my code can react to. At the moment, I'm doing it by checking through all of my sprites in a ...
1
vote
1answer
92 views

How to draw many identical quads in WebGL efficiently?

I have recently been trying to develop a more basic one of those 'falling sand'/'powder game' style games (See here) the past few months, and after prototyping on a plain canvas, then trying PIXI.js, ...
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vote
1answer
206 views

Implementing fog of war on HTML5 canvas

I have been wrestling with creating fog of war for a while now. I actually did create it, but I consider the implementation too resource-heavy to be usefull. For initial information: I use createjs / ...
0
votes
2answers
219 views

translating canvas for rotating sprites that shoot

I am trying to align bullets to my different sprites guns (top down 2D for android). Right now Im using this method to draw my bullets: public void draw(Canvas canvas){ update(); ...
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0answers
55 views

detection of a circle inside a rectangle in html5 canvas

I've created this game where the player can hit space to make the circle float in certain way. the main goal of the game is let the circle enter the rectangle .I did this code to create a collision ...
1
vote
2answers
397 views

HTLM5 canvas game (easeljs) slow peformance on ipad (ios7) with phonegap

I have developed a game with easeljs for HTML5 Canvas. the game is a single HTML5 page with canvas and a lot of javascript. All this time I tested the app on iOS Safari (iPad3 iOS7) with 40~50 fps ...
0
votes
1answer
101 views

Alpha Value at 0 Shows Black for Android Canvas Bitmap

There have been a few questions similar to this but none seem to give a straight answer. If I am creating a Bitmap from a .png image and want to set a color (i.e. true pink) to transparent, the color ...
1
vote
1answer
68 views

UI in Canvas-Games [closed]

I am quite new to programming with <canvas/> and WebGL, but very familiar in HTML5. So far, I have made to render some entities on the <canvas/>. Next would be to add a simple HUD to it. ...
1
vote
1answer
237 views

Is it possible to rotate an image on an HTML5 canvas, without rotating the whole canvas?

So I basically want to rotate single sprites on the canvas without rotating the whole canvas, is that someway possible. I also don't want to create a new canvas for each object I have. Also, it ...
1
vote
1answer
162 views

Replace a div (with a ball picture in it) with a 3D canvas ball [closed]

I am trying to make a game where you have to keep the ball on a green platform. At this point the ball is a div with a ball image. You can move the ball over the field, all works great. See it in ...
1
vote
0answers
61 views

Is pre-rendering Canvas graphics with ImpactJS safe? [closed]

I have several fairly complex menus I'm loading into my HTML5 game created with ImpactJS (skill trees, journal, equipment, ect). In order to draw them with a low performance impact I'm rendering them ...
0
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0answers
78 views

Coordinate system of android.graphics.Camera?

I asked this question before in StackOverflow.But I have not found any answer. I have to use Camera to draw some things in Canvas.But I can not detect that coordinate system of Camera is Right hand ...
2
votes
2answers
150 views

Testing HTML5 canvas games on low resource computers

I've made a game in HTML5 & JS and want to test it on varying types of user setups as I've heard it doesn't perform too well on older MacBooks. How can I accomplish this? I'm thinking of ...
1
vote
2answers
190 views

Best way to do “cutscenes” [closed]

I'm curious about the best way to display cutscenes in canvas. When I say cutscene I mean something like a static image fading from one to the other. Would it be best to use a timeout for a certain ...
2
votes
2answers
131 views

Glitch-free cross-fades in HTML5

In my HTML5 canvas game, I need to cross-fade two sprites which have some glow around them. (Glow is backed into sprites.) Initially, the first sprite is visible. During the cross-fade the first ...
1
vote
1answer
276 views

Do you need to make a tileset for a platformer?

I've been tasked to make a platformer, I've never made a tiled game before, is this necessary? I.e. can I just make different child classes of a Sprite class and add place them on the map, adding ...
2
votes
1answer
300 views

OpenGL slower than Canvas

Up to 3 days ago I used a Canvas in a SurfaceView to do all the graphics operations but now I switched to OpenGL because my game went from 60FPS to 30/45 with the increase of the sprites in some ...
0
votes
1answer
123 views

Why does my goblin only choose a walk direction once? [closed]

I'm working on a simpe 2d canvas game that has a small goblin sprite who I want to get pathing around the screen. What I originally tried was a random roll that would choose a direction, the goblin ...
0
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0answers
22 views

Bones & Blood Sprite [duplicate]

I'm currently playing with a small 2d canvas game for fun. I'm looking for some images, primarily some bones and blood to be left in an XY position after killing an enemy. Does anyone know where I'd ...
1
vote
3answers
107 views

Can I use a translate function to implement a viewport?

I read this great question and its accompanying great answer about rendering a viewport in a top down 2D game: As for actually drawing the objects the camera can "see", you now draw all objects ...
0
votes
2answers
189 views

HTML5 Canvas Parsing image into tileset while preserving transparency

I'm trying to import a Tiled Map Editor JSON file into my HTML5 canvas game but I'm having trouble with separating out the tileset image into separate images while preserving the transparency. ...
0
votes
0answers
18 views

Fixed print on GLCanvas surface

Having extends class of GLCanvas and I want to print some fixed texts and pictures on its surface. What is the intelligent solutions for that ? So far I have - class PhaseOne extends GLCanvas ...
1
vote
2answers
318 views

Algorithm to zoom a plotted function

I'm making a game in android and I need plot a function, my algorithm is this: @Override protected void onDraw(Canvas canvas) { float e = 0.5f; //from -x axis to +x evaluate ...
0
votes
0answers
81 views

Bouncing objects against the side of the screen

I want to have certain circular objects bounce against all four sides of the screen. After searching a lot on the internet, I found the following formula: Vout = Vin - ((1+e) *dot(Vnormal, Vin) * ...
0
votes
3answers
260 views

Is there a way to create multi-resolution graphics for game with createjs?

I'm on a advanced development for a game made with createjs framework. However it's time to export it to some platforms. The graphics are made for the iPad 3 resolution. I would like to export them ...
0
votes
1answer
189 views

“Painting” elements in html5 canvas

I'm making a game in coffeescript (although for the sake of this problem that's probably not all that relevant) and html5's canvas. It's a game that involves a paint cannon, that fires circular ...
1
vote
2answers
191 views

Bullet entry Point around Player Object

I have a player rotating by the mouse and want the bullets line up with the player's gun. Right now they simply come from the point of the player and shoot in the direction of mouse. I just need the ...
1
vote
2answers
476 views

How can I create and animate 2D skeletons for HTML5 Javascript games? [closed]

I'm trying to make a 2D fighting game in HTML5(somewhat like street fighter). So basically there are two players, one AI and one Human. The players need to have animations for the body movements. ...
1
vote
2answers
176 views

Make perfect constant game animation using javascript

I tried different ways to make constant animations using JavaScript and HTML. The problem is that they are never perfect. If I want to move a square exactly 5 pixels every 50 miliseconds I would use ...
3
votes
1answer
282 views

Multilayer game HTML5 canvas

I've have a problem with HTML5 canvas and using multiple layers. I'm using 3 layers. The first layer is where the player and the collision base objects are. And the second and the third layer have ...