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

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-1
votes
1answer
121 views

creating an html5 game [closed]

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
253 views

How do I use createPattern with a spritesheet? [closed]

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 ...
-2
votes
2answers
142 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 ...
1
vote
2answers
2k 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
392 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 ...
0
votes
0answers
68 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 += ...
3
votes
1answer
5k 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 ...
5
votes
3answers
398 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 ...
10
votes
5answers
5k 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 ...
4
votes
2answers
1k 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
128 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 ...
0
votes
1answer
421 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). ...
-1
votes
2answers
637 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.
1
vote
2answers
138 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
66 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
331 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
70 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
392 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 = ...
0
votes
0answers
20 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
940 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
704 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, ...
1
vote
1answer
468 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
505 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(); ...
1
vote
2answers
2k 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
2k 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
179 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. ...
4
votes
1answer
7k 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
354 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
99 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 ...
2
votes
2answers
181 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
322 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
291 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
556 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
2k 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
132 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 ...
1
vote
3answers
148 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
486 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. ...
1
vote
3answers
393 views

Algorithm to zoom a plotted function [closed]

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
3answers
625 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
282 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
313 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
1k 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
284 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
460 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 ...
1
vote
0answers
59 views

Improving performance on older Androids

I'm learning to build html5 games for mobile. I'm worried about the FPS animation on older model Android... as I use a lot of setTimeouts to update certain aspects and would like some suggestions on ...
6
votes
2answers
3k views

Is using multiple canvas objects a good practice?

We're developing a jump and run game with HTML5 and JavaScript and have to build an own game framework for this. Here we have some difficulties and would like to ask you for some advice: We have a ...
2
votes
3answers
1k views

Map building - Tower Defense

Before diving too deep into my question, let it be known that I am learning as far as java script goes and figured a simple Tower Defense game would be an excellent way to learn things. So I have ...
1
vote
3answers
105 views

Move from point a, to point b, and determine the accuracy

Let's say I have a circle at point a (0,0), and I wish to move it to point b (23,58), whatever, how can I accurately do this with a speed variation if I wanted. (I'm doing this in javascript). Every ...
0
votes
3answers
523 views

how can we define dynamic Path of ViewObject(Bitmap) On Canvas

I am Currently working on One 2D Android Game, In this game One ViewObject(Bitmap) is moving Across Screen On Parabola Path Like in this Image, But this Path is Static, the Static path is getting ...
-2
votes
1answer
61 views

Error returning a value from a function? [closed]

It tells me the error is on this line: this.srcX = ShipSrcXPicker(type); However I cannot see it? I am returning the values from these methods that are being called? Is there something I am missing? ...