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

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0
votes
1answer
60 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
285 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
65 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
262 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
729 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
498 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
396 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
405 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
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
1k 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
143 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
5k 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
289 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
95 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
175 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
270 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
249 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
483 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
1k 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
130 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
136 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
381 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
378 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
523 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
265 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
284 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
923 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
257 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
400 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
56 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
2k 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
104 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
481 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
60 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? ...
0
votes
2answers
217 views

Physics for space game [duplicate]

I am making a space game where you fly a ship. I am trying to work out the physics for such a game and so far came up with: var thrust; //between 1 & 100 how much the engines are pushing var ...
-4
votes
2answers
287 views

Moving Character Based on background [closed]

I want to know how can i move the following character just in predefined areas as shown in the bg.jpg file character http://s7.postimg.org/ezyaclrrb/walking.gif bg ...
0
votes
1answer
378 views

How can I draw a small bitmap on a larger bitmap at a particular position? (Canvas / SurfaceView)

I'm building a game that requires additive blending of colours for certain bitmaps. Say I have 4 different types object, there are maybe ten of each type on the screen with each type having a ...
3
votes
4answers
959 views

Why wouldn't one use Canvas for HTML 5 game development? [closed]

I'm just getting into the HTML 5 game development. I've discovered that some games seem to be created using just JS/CSS/HTML instead of the canvas. Since canvas seems to enjoy good browser ...
-1
votes
1answer
351 views

View port for my canvas game

I am developing a canvas game, and im struggling to get my head around how i can make a view port so when the character moves the world moves with it. Unlike traditional 2d maps built with arrays i ...
2
votes
1answer
513 views

JavaScript - 2D Top-down Tile Collision Detection

I am developing a small Top-down Game (Much like the old Zelda Games) and I'm having an issue in terms of Collision detection (The actual theory itself rather than assigning Tiles as solid, etc.) I ...
2
votes
1answer
346 views

Low FPS on Java drawing in BufferStrategy

I ran into a very strange problem while using BufferStrategy, I've tried searching for an answer but all I have found are non-relevant threads and discussions. So here is my query. for (int i = 0; i ...
0
votes
1answer
328 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 ...
8
votes
5answers
1k views

Good technological solutions to build an ascii map and moving characters in a browser (like dwarf fortress)? [closed]

I'd like to build a webapp for my game website that involves using text characters to represent animals and people, and have them move around on map squares with independent (server driven) AI. So ...
1
vote
1answer
324 views

Canvas isometric translations to integer coordinates

I'm creating a canvas based game with an isometric playing board. I use the following transformations to get my square tiles to render on the screen: 'applyViewportTransformation' : function() { ...
4
votes
1answer
268 views

How can I full-screen a Facebook canvas game?

Is there any way to allow the user to click a button on a Facebook canvas app and allow the app to go full-screen? If it's possible, is it permitted by Facebook?
0
votes
2answers
2k views

Moving a sprite towards an x and y coordinate

Given a sprite with an x and y coordinate, how would I move it toward another sprite with an x and y coordinate? I've already made it face towards the other sprite, and I've made it move towards the ...
0
votes
1answer
2k views

Simple javascript HTML5 canvas start menu

I'm currently looking for a simple and basic start screen for a game using javascript, so basically its the first function that is called and then press play which then goes into the game. Looked ...
2
votes
1answer
1k views

Implementing a camera on HTML5 canvas?

I am trying to work out the best way of implementing a camera in my simple 2d game. The way it is structured at the moment is my game objects all have draw functions, which are passed a canvas ...