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

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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
353 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
98 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 ...
3
votes
1answer
1k 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 ...
3
votes
2answers
16k 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
180 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
320 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
1k 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
553 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 ...
5
votes
5answers
3k 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 ...
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
478 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. ...
0
votes
3answers
623 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 ...
2
votes
2answers
6k views

Rotate canvas along its center based on user touch - Android

I want to rotate the canvas circularly on its center axis based on user touch. i want to rotate based on center but its rotating based on top left corner . so i am able to see only 1/4 for rotation ...
0
votes
1answer
280 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
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 ...
1
vote
2answers
1k views

How to draw a tileset using HTML5 canvas?

I have a tileset something like this: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 My tileset draw code looks like this: var image = new Image(); image.src = ...
3
votes
1answer
458 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 ...
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 ...
0
votes
3answers
522 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 ...
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
2answers
251 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 ...
-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? ...
-4
votes
2answers
310 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
440 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 ...
-1
votes
1answer
404 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
556 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
425 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 ...
1
vote
1answer
348 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() { ...
15
votes
6answers
6k views

Are there any alternative JS ports of Box2D?

I have been thinking about creating a top down 2D car game for HTML5. For my first game I wrote the physics and collisions my self but for this one I would like to use some ready made library. I ...
1
vote
1answer
4k views

How to initialize a BitmapDrawable Android

I have been using a shapeDrawable object for my android games player but now that i want to add some graphics in I have to use something different I was thinking of a BitmapDrawable but as I am new to ...
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
2k 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 ...
21
votes
7answers
11k views

HTML5 Game (Canvas) - UI Techniques?

I'm in the process of building a JavaScript / HTML5 game (using Canvas) for mobile (Android / iPhone/ WebOS) with PhoneGap. I'm currently trying to design out how the UI and playing board should be ...
2
votes
2answers
2k views

Receiving keyboard events on a canvas in Javascript

I need to receive keyboard events in a canvas element. Click events are received but key presses aren't. Here is my code which doesn't handle key events: var canvasElm = $('canvas'); ...
2
votes
3answers
5k views

Slow Firefox Javascript Canvas Performance?

As a followup from a previous post, I have been trying to track down some slowdown I am having when drawing a scene using Javascript and the canvas element. I decided to narrow down my focus to a ...
1
vote
1answer
474 views

How to create an array of images on a canvas

I am developing a game that uses different images.When am image is swiped to the bottom of the screen it disappears and a new image appears at the top.Seeing as you can't delete an individual image I ...
6
votes
3answers
1k views

Basic isometric projection in Javascript

I've been working on porting an old closed source game to Javascript with Canvas and I've come to a slight problem. Right now, to display the land, I just have a pretty basic loop that just draws the ...
0
votes
2answers
641 views

Animating sprites in HTML5 canvas

I'm creating a 2D platformer game with HTML5 canvas and javascript. I'm having a bit of a struggle with animations. Currently I animate by getting preloaded images from an array, and the code is ...
2
votes
1answer
394 views

Collision detection problems - Javascript/Canvas game

What I want to do: I simply want the have a 2D array to represent my game map. I want a player sprite and I want that sprite to be able to move around my map freely using the keyboard and also have ...
0
votes
1answer
372 views

Player movement behind objects

I was playing around on RPG JS and Browser Quest, and the player, when moving, can give the effect of walking behind the trees or houses etc, so the player effectively disappears while it is "behind" ...
5
votes
1answer
1k views

Canvas animation drops to 30fps every 3-4 seconds

Ok! I solved the problem. Chapter One - Multiple Canvases I started to make pong utilizing requestAnimationFrame and I noticed that the ball was stuttering and slowing down every 3-4 seconds. So I ...
2
votes
1answer
181 views

Difference between rotation methods?

My question is in about rotate methods in android.graphics.Camera. In Docs, I saw these comments: public void rotateX (float deg) Since: API Level 1 Applies a rotation transform around the X ...
-1
votes
2answers
401 views

Remove enemy when bullet hits enemy

For my education I have to make a basic game in HTML5 canvas. The game is a shooter game. When you can move left -> right and space is shoot. When I shoot the bullets will move up. The enemy moves ...
-5
votes
2answers
677 views

A* mouse movement javascript top-down game

Im trying to implement a* path finding for my character movement in my game. The game is written in javaScript along with jQuery in a canvas. I have read up on A* so i believe i understand what it ...
23
votes
3answers
7k views

Double buffering on HTML5 Canvas game?

My simple canvas game seems to work fine on Chrome and FF on Mac/Linux. I haven't had chance to test it on smart phones or Windows environments yet. It doesn't use double buffering but I have seen ...