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

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1answer
2k views

JavaScript rendering: Canvas or DIV?

I am planning on developing a multiplayer RPG (kinda like RuneScape, but don't worry, with a different gameplay) and i want to do this in the browser. Now before saying things like "A MMORPG is hard ...
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vote
1answer
1k views

HTML5 Canvas Depth Sorting

I'm have problem with Isometric. I'm don't know how to name this "problem", but I'm show you some sceen what I get and what I'm need to get. My code now drawing something like: ...
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vote
1answer
2k views

Easy way to do gravity in a simple game?

I'm looking for an easy, beginner friendly way to do gravity in a platformer. I've looked into Box2D tutorials, but they all seem very complicated. All I want is a class that takes into account if my ...
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3answers
1k views

2D maps, how to structure?

I'm new to this. And I don't really understand 2D tile maps. The tutorials I've read use arrays, but doesn't this get really difficult to manage when they get big? And what if I want different ...
6
votes
1answer
2k views

HTML5 Canvas Converting between cartesian and isometric coordinates

I'm having issues wrapping my head around the Cartesian to Isometric coordinate conversion in HTML5 canvas. As I understand it, the process is two fold: (1) Scale down the y-axis by 0.5, i.e. ...
1
vote
2answers
770 views

Multiple setInterval in a HTML5 Canvas game

I'm trying to achieve multiple animations in a game that I am creating using Canvas (it is a simple ping-pong game). This is my first game and I am new to canvas but have created a few experiments ...
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8answers
10k views

How should I sort images in an isometric game so that they appear in the correct order?

This seems like a rather simple problem but I am having a lot of difficulty with it. What should I do to properly sort images in an isometric game? In a normal 2d top-down game one could use the ...
2
votes
2answers
360 views

how to transform child elements position into a world position

I'm making a 2d space game in Javascript with canvas. In this game there's a bunch of spaceships, positioned in world space, with turrets, positioned relative to their parent ships. These objects also ...
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1answer
405 views

How to select an image on the J2ME Canvas

I am working on J2ME. I have got a canvas, with a layout of a Checkers board. At the position of pieces, I have placed images. The point at which I got stuck is, how to select/highlite a piece's image ...
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1answer
1k views

HTML5 Canvas Tileset Animation

How to do in HTML5 canvas Image animating? I am have this code now: http://jsfiddle.net/WnjB6/1/ In here I am can add animations something like -> Animation.add('stand', [0, 1, 2, 3, 4, 5]); But ...
5
votes
4answers
2k views

Defining the track in a 2D racing game

I am designing a top-down racing game using canvas (html5) which takes a lot of inspiration from Micro Machines. In MM, cars can move off the track, but they are reset/destroyed if they go too far. ...
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vote
2answers
534 views

Frustum Culling/Only rendering what's viewed by the Camera in HTML5 Canvas?

I coded up a simple 2D Camera for my HTML5 Canvas-Based Game Engine but I noticed the performance wasn't very good. So a lot of people suggested only rendering things that are shown by the camera but ...
3
votes
1answer
891 views

HTML5 Canvas fillStyle as numbers not text

When drawing vector graphics in the canvas you set the fillStyle using an rgba string like this... context.fillStyle = "rgba(255, 223, 191, 1)"; Is it possible to feed in a javascript object ...
3
votes
2answers
167 views

Deactivate keyboard input on collision

I'm creating an online-canvas-game with a tank as player object. Now I have several structures in my canvas, that shouldn't be able to be overdriven by the tank... My solution is to detect the ...
4
votes
2answers
2k views

canvas ball physics animation

I want to animate ball in html canvas like this. ctx.beginPath(); ctx.arc(75, 75, 10, 0, Math.PI*2, true); ctx.closePath(); ctx.fill(); start position is left top corner and ball's maximum ...
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0answers
67 views

ball 2d animation [duplicate]

Possible Duplicate: canvas ball physics animation I want to animate ball in html canvas like this. ctx.beginPath(); ctx.arc(75, 75, 10, 0, Math.PI*2, true); ctx.closePath(); ctx.fill(); ...
13
votes
1answer
14k views

Multiplayer HTML5, Node.js, Socket.IO [closed]

I trying create simple Multi-player with HTML5 Canvas, JavaScript(too using John Resig simple Inheritance library) and Node.js with Socket.IO. My client code: var canvas = ...
1
vote
1answer
872 views

Converting coordinate systems to/from an isometric game world

I have tried searching and reading for an answer, but the information I could dig up either didn't fit what I need or was in the form akin to "Just multiply the vectors with the inverse matrix of.." ...
0
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1answer
1k views

How to display a tile map from a 2D array in JavaScript?

I have stored my map, but the problem I am having is displaying it. My map is 100x100 tiles which are 40x40px. I have my loop running through the array but I'm having difficulty selecting the portion ...
3
votes
1answer
2k views

Canvas tile grid, hover effects, single tilesheet, etc

I'm currently in the process of building both the client and server side of an HTML5, canvas, and WebSocket game. This is what I have thus far for the client: http://jsfiddle.net/dDmTf/20/ Current ...
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vote
2answers
1k views

Matrix rotation of a rectangle to “face” a given point in 2d

Suppose you have a rectangle centered at point (0, 0) and now I want to rotate it such that it is facing the point (100, 100), how would I do this purely with matrix math? To give some more specifics ...
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2answers
3k views

Creating several instances of the same object, and selecting only one

I'm playing around with making a puzzle game, haven't done that much before I run into my first problem. I want to create a certain amount of the same object/function. But without hardcoding the ...
10
votes
2answers
625 views

Dirty 2D map rendering

I keep hearing people talk about "dirty rendering" when it comes to map rendering for HTML5. I've Googled and searched the GameDev about it but there isn't much about it. What exactly is it? How to ...
3
votes
0answers
259 views

Choosing a (browser) game environment [closed]

I apologise in advance if this post is something you've heard a million times already or seems like a trolling attempt. I just want some advice and I'm coming up short with my own Google searches. ...
5
votes
4answers
2k views

Making a startscreen for an HTML5 game?

How would I make a start screen for a game using HTML5 canvas? I'm not looking for something advanced, just the new game button and highscore link etc. The question might be stupid, but I've never ...
2
votes
2answers
1k views

Drawing isometric map in canvas / javascript

I have a problem with my map design for my tiles. I set player position which is meant to be the middle tile that the canvas is looking at. How ever the calculation to put them in x:y pixel location ...
3
votes
1answer
306 views

How do I show the current view from the viewport on my map?

I'm doing HTML5 Canvas development and currently have a large viewport (on the left) and a map (on the right). Like this: I need to show on the map what is currently being viewed in the left. And ...
2
votes
2answers
464 views

Collision Detection doesnt work because some things move more than 1px at a time

I'm writing a 2d scrolling game in javascript using canvas and since I'm limited to setInterval running at minimum once every ms, I need to have some objects moving at greater than 1 pixel a second. I ...
1
vote
1answer
282 views

Isometric Optimization in javascript

I'm having some issues with my optimization of my game. I have a simple tile map looped like this in my case the images are 64 by 64 pixels: for (i=0; i < 50; i++){ //horizontal for (j=0; ...
4
votes
2answers
680 views

HTML5 multi-player game data/event validation best practices

I'll start by saying that I am fully aware that this question might seem subjective at first, but I'll try and provide a specific test case scenario for it to be a clear question about validating the ...
1
vote
1answer
1k views

Android-Handling screen clicks for dynamically moving objects in a view

I have a kind of broad question to ask but I have to start some where so.....What is the best way to handle onscreen clicks for moving objects being drawn on a canvas in a view. Im registering the ...
2
votes
1answer
2k views

Collision detection between a sprite and rectangle in canvas

I'm building a Javascript + canvas game which is essentially a platformer. I have the player all set up and he's running, jumping and falling, but I'm having trouble with the collision detection ...
3
votes
2answers
3k views

HTML5 canvas screen to isometric coordinate conversion

I am trying to create an isometric game using HTML5 canvas, but don't know how to convert HTML5 canvas screen coordinates to isometric coordinates. My code now is: var mouseX = 0; var mouseY = 0; ...
3
votes
3answers
426 views

Commonizing cycle time across different browsers for HTML5

Is there a good (accepted) method for "fixing" the cycle time within an HTML5 canvas game implementation? The game that I have been working on runs far quicker in Google Chrome than in other browsers ...
10
votes
2answers
1k views

How should I handling clipping vertices that are closer to the eye than the near clip plane?

I'm rolling my own 3D engine in Javascript and using only canvas drawing, no WebGL. This is another Minecraft clone, I love boxes, don't judge me. So far everything works wonderfully, except for one ...
3
votes
1answer
2k views

Optimizing HTML5 canvas transformed drawing in Javascript

I am trying to optimize my HTML5 game engine and have noticed that currently a majority of the time taken in the game loop can be taken when drawing transformed tiles. I think this is because each ...
2
votes
2answers
1k views

Canvas Rotation collision detection on a sprite

I am using this code to detect collisions between two rectangular sprites. intersect: function(other) { return this.x < other.x + other.width && other.x < this.x + this.width ...
1
vote
1answer
5k views

How to rotate a moving canvas in Android

I am developing an Android game. In this game some trains are moving on tracks. I am able to move trains horizontally and vertically using two train images for horizontal train and vertical train ...
3
votes
1answer
664 views

Best resources for Canvas Html 5 development

I am at a competition at work for who can make the best canvas game. Theme is a top down shooter... Winner gets dinner for free. Anyways I have been looking around looking for some good resources on ...
7
votes
2answers
1k views

How to scroll hex tiles?

I don't seem to be able to find an answer to this one. I have a map of hex tiles. I wish to implement scrolling. Code at present: drawTilemap = function() { actualX = Math.floor(viewportX / ...
1
vote
1answer
689 views

Calculating bullet travel knowing coordinates and radian

I have a player sprite that has a x and y coordinate and also a radian. The radian determines which way the sprite faces in a top-down game interface. In this case, the radian points from the player ...
8
votes
1answer
1k views

Set sprite to face direction of mouse

I'm building a html5 canvas game and I need a way to get my sprite to face the mouse cursor. I have the X and Y co-ordinates for the sprite, and also the X and Y co-ordinates of the pointer. All I'm ...
8
votes
2answers
2k views

How to efficiently store and display a tile map on the web?

About These are actually two questions in one. First of all I am looking for a way to efficiently store large amounts of tile data. The other aspect deals with querying the data set and displaying ...
2
votes
2answers
377 views

How to draw objects that have a smaller Y axis first?

In my game there is a large 2D map of various objects. Example. As you see, upon creation objects of the same type (trees for example) are placed correctly, but objects of another type (enemies) are ...
3
votes
1answer
7k views

How do I make magenta in my PNG transparent in HTML5/Canvas/JS?

I'm putting together a simple hex map to use within an HTML5 / Canvas / JS game and before I get round to sorting any custom graphics, I was wondering if anybody knew how to make the pink/magenta ...
2
votes
2answers
634 views

Animating sprites at different speed than what the game runs at

I am building a Javascript/canvas platformer game, and it's coming along nicely. The only problem I've really run into where I can think of any solution at all is the animation of my player sprite. ...
5
votes
1answer
4k views

How do I implement side scrolling in a javascript platformer?

I'm building a side scrolling platformer with Javascript and the canvas element for a school project. I have the character all sorted out. He runs left and right, and has a different sprite set for ...
1
vote
1answer
1k views

Has anyone used PhoneGap to make 2D games for the iPhone? [closed]

I love simple casual games. I've been riding the bus a lot recently and so simple, no-brainer games are great fun and well worth the small price I pay on the App Store. It got me thinking... I know ...
6
votes
2answers
2k views

Calculating the angular direction from velocity

I'm trying to calculate the angular direction of a projectile, knowing it's X and Y velocity I can find the magnitude of its movement, but I'm having a hard time wrapping my mind around getting the ...
0
votes
1answer
341 views

Drawing slope lines in a confined space

This isn't a game development question per se, but here goes... I have a 50x50 pixel space in which I need to draw five lines: X and Y axes, and one line for each of a steepest, average, and flattest ...