Tagged Questions

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

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1
vote
0answers
20 views

Offset during zooming to keep object within boundries

I have a simple zoom feature which lets the user zoom in and out. I'm having an issue how ever when i zoom out the object gets smaller to the point that the boundaries become broken. The idea is the ...
0
votes
1answer
18 views

Android Canvas 2D Game: Supporting multiple screen sizes/resolutions [duplicate]

I'm planning to develop a 2D game for android devices by using simple Canvas Surfaces (I know that OpenGL might be more efficient - but Canvas should definitely be enough for my type of game). I'm ...
1
vote
1answer
78 views

How do I procedurally create a directional light cone with an HTML canvas?

To create a directional light effect, I want to draw this kind of transparency mask on an HTML canvas (using context2d): I also want to be able to generate such a mask dynamically. I've tried using ...
0
votes
1answer
80 views

Map scrolling around the world

I am developing an TBS (turn based strategy) game. I have created a simple canvas renderer to render hexagonial map. I already implemented scrolling on the map. My current problem is that I want to ...
0
votes
4answers
121 views

How to handle a negative coordinate 2d map with a growing map size

I love this procedural generation theory and have been messing around with it. However I'm having trouble wrapping my head around how to store my map data. Usually I store my map data in a 2d array ...
3
votes
3answers
320 views

Procedurally Generated Top View 2D RPG Map Generation

Procedural generation is a fascinating concept and is gaining popularity in the gaming industry. The thought of playing a game that has new content every-time the game is played is very exciting to ...
0
votes
0answers
42 views

Drawing a object with Box2D and HTML5 canvas on current mouse position

I'm attempting to create a air hockey type game with HTML5 canvas and JavaScript, using Box2dWeb for the physics calculation. I need a way to draw the puck at the current mouse x and y position every ...
1
vote
1answer
49 views

Removing a previously rendered image on a canvas

I made a platformer using ctx.clearRect and ctx.fillRect, so each time the player moved I would just delete the previous position and draw him again. Now I'm working on importing my own art into the ...
0
votes
0answers
78 views

Puzzle Game on Android using canvas with matrix

I'm making a slide puzzle game on android. I have handled the gestures and tranaslate the matrix that holds the pieces succesfullly, and I have made the logic when the pieces get on the border of the ...
0
votes
0answers
41 views

How do I repeat parts of some images in 2D Array in JavaScript but not all of them?

OK, I am trying to make a game that is a little bit like SimTower but utilizing HTML5 (particularly the canvas element) and JavaScript with a little CSS. I have progressed pretty far in the past week ...
0
votes
2answers
181 views

How to move an image back and forth with javascript

I currently am trying to make a baseball game and have this code here: http://jsfiddle.net/769BK/ I have the baseballX set to a decrement, and then I try increasing the value using baseballX++; but it ...
0
votes
2answers
181 views

How to move an object using X and Y coordinates in JavaScript

I am making a 2d baseball game with JavaScript and HTML5 and am trying to move an image that I have drawn with JavaScript like so: //canvas var c = document.getElementById("gameCanvas"); ...
0
votes
0answers
97 views

Drawing and scrolling paths performance problem

Hi I'm doing and endless sidescroller game where the terrain looks like a tunnel which is infinite. I managed to randomly generate the tunnel using this code: protected void createPath(){ path = ...
1
vote
2answers
140 views

How can I make EaselJS' skew behave like canvas'?

The skew property of a bitmap in EaselJS (given as angle) rotates the image such that it also flattens. I'd like to skew it without "squashing" it, as canvas does. JSFiddles, to demonstrate: Canvas ...
1
vote
2answers
76 views

How do you account for zoom in a top down viewport?

I've been stumped on this for days so please forgive me if this question is in bad-form. I have a generic top-down RPG structure, and I want to create a zoomable Canvas viewport for it. I've read ...
1
vote
2answers
105 views

Canvas - darken sprites rendered by drawImage

I am implementing lighting in a tile engine, and I need a way to darken tiles, based on their light level. For the ground tiles, I can clear the context to black, then set the globalAlpha and use ...
0
votes
0answers
65 views

EaselJS SpriteSheet isn't responding to gotoAndPlay

I'm developing a Fez-based HTML5 Canvas game using EaselJS and I've found a problem, that I can't solve myself, while trying to implement SpriteSheets to the hero. The problem is that I've defined ...
-1
votes
1answer
98 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
95 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
120 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
716 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
134 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
55 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
2k 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
246 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 ...
7
votes
0answers
3k 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
451 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
104 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
175 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
261 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
238 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
113 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
48 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
223 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
62 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
160 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
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
429 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
298 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
294 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
308 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(); ...
0
votes
0answers
149 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
1k 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
575 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
111 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. ...
2
votes
1answer
3k 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
237 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
82 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
172 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
229 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 ...