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

learn more… | top users | synonyms

0
votes
1answer
256 views

Should I render all of my HUD views to a single SurfaceView?

I'm using a SurfaceView and canvas to implement a game HUD, title screens etc., by overlaying standard Android view widgets over my SurfaceView. This works reasonably well and maintains an acceptable ...
0
votes
1answer
3k views

How To Scale Canvas In Android

I am writing a android game using Canvas as the way to draw everything, the problem is that when i run it on different android phones the canvas dosn't change size i tried using canvas.scale() but ...
1
vote
2answers
387 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 ...
2
votes
0answers
307 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 ...
2
votes
1answer
28 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 ...
0
votes
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 ...
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
1answer
35 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 ...
-2
votes
1answer
1k views

How to make Moving road/track for android game? [closed]

I am very much new to Android game development. and i have little idea about the canvas and open GL. in one of my requirement i wanted to draw a moving road/track(Jazzy). how should i start. please ...
1
vote
1answer
46 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
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
180 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 ...
10
votes
0answers
903 views

How to create 2D shadows [duplicate]

I'd like to create lights and shadows in a 2D environment, like in the image below: I did several searches but got no results. Do you have any hint?
4
votes
0answers
143 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
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
2answers
233 views

How can I center a circle around a point on an HTML canvas?

I've got a job to make an engine and light game for canvas in HTML5. I like the things I make to be centered on the x,y positions I give it, I don't know why, it just helps me think about them ...
3
votes
2answers
117 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
83 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.
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 ...
0
votes
0answers
63 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). ...
1
vote
2answers
81 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
92 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 = ...
22
votes
2answers
957 views

My game is just about finished! What do I do now? [closed]

I have an HTML5/canvas game just about finished and ready to launch. It's a 2d game in which you explore and disrupt a procedurally-generated landscape, crafting items and structures to survive. I ...
0
votes
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 ...
0
votes
2answers
216 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(); ...
3
votes
1answer
120 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 ...
2
votes
1answer
213 views

How can I repeat only a portion of an image in Javascript?

So I'm trying to repeat a portion of my spritesheet as a background. So far, I have attempted this: var canvas = $("#board")[0], ctx = canvas.getContext("2d"), sprite = new Image(); ...
6
votes
1answer
604 views

Jump handling and gravity

I'm new to game development and am looking for some help on improving my jump handling for a simple side scrolling game I've made. I would like to make the jump last longer if the key is held down ...
1
vote
1answer
203 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 / ...
1
vote
1answer
90 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
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. ...
0
votes
0answers
54 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 ...
0
votes
1answer
98 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 ...
5
votes
1answer
972 views

What's the difference between Canvas and WebGL?

I'm thinking about using CAAT as a part of a HTML5 game engine. One of it's features is the ability to render to Canvas and WebGL without changing anything in the client code. That is a good thing, ...
0
votes
1answer
609 views

Tile Map Coordinates

I am have now this code: http://jsfiddle.net/DK67k/2/ In here is 2D tile map and when you click on tile you get coordinates on alert. But for get precises coordinate you need click on top left ...
1
vote
1answer
227 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
161 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
60 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
votes
0answers
77 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 ...
3
votes
1answer
907 views

Converting cartesian geo-coordinates to isometric (real world map to game map)

I need to create an automated method to convert real cartesian, geo-coordinate data (such as roads and parks), into isometric coordinates as a game map view for use in HTML5 Canvas. Here is an image ...
2
votes
2answers
9k views

How to update off screen bitmap in a surfaceview thread

I have a Surfaceview thread and an off canvas texture bitmap that is being generated (changed), first row (line), every frame and then copied one position (line) down on regular surfaceview bitmap to ...
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 ...
3
votes
2answers
856 views

HTML5/JS - Choppy Game Loop

I have been experimenting with HTML5/JS, trying to create a simple game when I hit a wall. My choice of game loop is too choppy to be actually of any use in a game. I'm trying for a fixed time step ...
1
vote
1answer
273 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 ...
4
votes
5answers
2k views

What would be a good way to implement/render a 2D tiled map for a browser game?

I coded a a little RPG in ruby and I used an array to contain the map squares. The elements of the array (which defines the X coordinates) are arrays themselves whose elements defines the Y ...