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

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0
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0answers
17 views

How to display a lot of small objects using WebGL?

Introduction The game scene contains a lot of 10x10 pixel elements: for 1980x1200 px. screen the number of elements on the scene can vary from 0 to 23760 (elements cannot intersect). The live ...
-1
votes
0answers
17 views

HTML5 2D/2.5D engine with region invalidation [on hold]

There are lots of HTML5 game engines today. I am looking for engine with some specific functionality: It should be 2D/2.5D engine completely written in Javascript and using Canvas to draw ...
0
votes
1answer
25 views

HTML Canvas Makes Everything Bolder On Right Side

For some strange and sudden reason, my canvas seems to make lines thicker and darker on the right ~1/4-ish. I have tried multiple browsers and different computers and they all have the same rendering ...
1
vote
0answers
49 views

Drawing a hexgrid on a canvas, yet making it zoom/scrollable?

I'm developing a game in JS / PHP. The game is basically a 2D plane (hexgrid) where each hex represents a location in space. In total, I'm drawing 25 * 25 hexes on a 1000x1000 canvas. I also draw ...
0
votes
1answer
381 views

How to draw small sprite bigger?

I have created an image with the resolution of 25px(width)*34px(height) (I know it's unusual, however it doesn't bother me now). The problem is that when I try to display it by creating a bitmap, it ...
1
vote
1answer
126 views

Drawing/adding shape objects with the mouse on html canvas

I've started with the canvas paint tutorial from link which worked fine with a few problems that can be fixed later. I've been checking a lot of posts on drawing shapes on the canvas but they all use ...
3
votes
1answer
299 views

Shadows in html5 canvas game

I'd like to ask for reference. I met an article about how to cast shadows in games. I'm using html5 canvas (currently without webgl) with javascript for my projects. The article mentioned above is ...
0
votes
1answer
2k 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
3answers
150 views

Javascript 2D top down handling player direction graphics

In my top down game I can move the character around and the character will even face the direction he is moving however there is some weird behavior I'm having when you hold down one direction and ...
1
vote
1answer
19 views

how to follow(center) a box inside canvas element

If inside a canvas I draw a box, and the I add arrows to move it, the box will eventually be out of my reach since it goes out the border and I cant see it. How could I follow the box so that it is ...
0
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0answers
33 views

Using canvas graphics instead of traditional sprites in phaser

Trying to learn phaser (total beginner with mild js experiance) and I'm following tutorials and such where everything is using sprites. I'm trying to get by with basic canvas shapes instead of ...
6
votes
5answers
13k views

Huge performance difference when using drawImage with IMG vs CANVAS

I put together a couple of simple tests that render an image to a canvas. One renders from an IMG, while the other renders from an offscreen CANVAS. You can see the code and results here: ...
4
votes
1answer
108 views

Fixed Time Step Flutter

I've seen a lot of questions about this problem, but really no solution. Hopefully I can explain the issue well enough that I can get some sort of closure on this problem. I'm using a Fixed Time ...
4
votes
2answers
9k 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 ...
5
votes
2answers
78 views

Create.js CPU High load

I'm new in Create.js and I'm trying to make countdown progress bar. I have this simple code: var stage = new createjs.Stage("timerCanvas"); stage.canvas.width = ...
0
votes
0answers
43 views

How to get the angle an object is travelling at

I'm trying to figure out how to get the angle an object is moving at, but have ran into a few problems. My player object is moved by rotating the entity left and right by using the left and right ...
3
votes
0answers
44 views

Check if a point is touching a user drawn curve in HTML5 canvas

I am having trouble detecting whether a ball is colliding with a red curve. The curve below is an example of what a user may draw on to the canvas. I can't think of any fast ways to detect collision ...
2
votes
0answers
30 views

Best practice/way for client to speak with server

I'm making a multiplayer game in HTML5 Canvas and Node using Express and Socket.io. It's a platformer style game and so far the players are able to see each other and move around on the screen. It ...
1
vote
1answer
43 views

Javascript canvas check if all recs on the screen overlap a new one

So I know the AABB collision detection formula, however, this code does not work. Whenever I press space, a new square pops up. But this new square can spawn inside another, something that I do not ...
1
vote
0answers
28 views

Facebook Canvas (web) Game for Desktop & Mobile Browsers

as the title suggests - I am about to develop a game for FB canvas. Will the game support mobile and desktop or do I have to create two different project/game setups for this? thanks
1
vote
1answer
94 views

How do I check if one square is overlapping another in HTML5 canvas

I have a little program that goes like this: Whenever somebody presses space, a blue square appears. The blue square shouldn't overlap with any other blue square. But the function that is checking ...
1
vote
1answer
115 views

Android canvas.drawColor throws a null object reference

I have two nearly identical methods, the first to draw a splash screen while assets are loading, and the second to draw all of the assets to the screen. The first throws a NullPointerException on ...
6
votes
4answers
325 views

Rotating sprite around another sprite

I am building a pool game, and I want to make the cue rotate around the white ball. Here is the live code: http://199.26.84.223/nocol.html Here is the code for the white ball: balls = ...
1
vote
1answer
324 views

Building a simple bomberman game with Node.js and Socket.io [closed]

I'm building this game mostly because I want to experiment with Node.js and Socket.io, and the game is more like a proof of concept. To start with, I have a 2D grid system as the game map. ...
0
votes
1answer
39 views

What determines the hit detection ordering for graphic elements in Unity (2d game)?

I have a bunch of overlapping buttons spread across several UI Canvases. The default mouse behaviour only registers hover/click events with one of the overlapping buttons, which is ideal for my ...
2
votes
3answers
1k views

HTML5 clicking objects in canvas

I have a function in my JS that gets the user's mouse click on the canvas. Now lets say I have a random shape on my canvas (really its a PNG image which is rectangular) but i don't want to include ...
0
votes
2answers
672 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 ...
0
votes
2answers
308 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 ...
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 ...
0
votes
0answers
19 views

Performance slows down on click event

I'm currently working on a game in node using socket.io and drawing onto canvas. I'm noticing that when I click during the game, character movement slows to a crawl. For context: I'm updating x,y ...
2
votes
0answers
60 views

tilting image for mode7 game in HTML5

I'm making a mode7 game like mario-kart and I need to tilt the image before I draw it, I have tried using a buffer canvas to tilt the image then draw it on the games canvas but this makes it laggy ...
0
votes
2answers
10k 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
3answers
562 views

Why does a UI button that is child to a canvas not appear in game view?

I am trying to place a button onto a canvas background using C# script. I want the button specific to the canvas (i.e., if I move the camera to look at another canvas, I do not want the button ...
6
votes
4answers
5k views

2D Collision in Canvas - Balls Overlapping When Velocity is High

I am doing a simple experiment in canvas using Javascript in which some balls will be thrown on the screen with some initial velocity and then they will bounce on colliding with each other or with the ...
1
vote
1answer
397 views

JS Canvas - Creating 2D Game lighting effect like Terraria

I just started working with canvas in HTML5 and with javascript. I'm pretty satisfied with my game so far: http://xenopal.dk/game-v1.1/. But I'd like to implement lighting as well in the style of ...
5
votes
3answers
471 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 ...
3
votes
1answer
157 views

Creating HTML5 Canvas Objects in Javascript [closed]

I'm currently trying to learn how to make HTML5 Canvas games with JavaScript. I would like to use object oriented JavaScript to manage the elements of the game, but i'm having trouble. I've done a lot ...
-2
votes
1answer
58 views

How do I clear the previous frames of a canvas animation?

I am trying to rotate an object, but all the previous frames still show up on the canvas. Here is my code. This didn't work: this.ctx.clearRect(0, 0, this.canvas.canvasWidth, ...
0
votes
1answer
67 views

android canvas rope swing

I'm creating the code, where a player swinging on a rope for the moment I got this double angle = Math.atan2(player_y - center_y, player_x - center_x) - Math.atan2(end_y - center_y, end_x - ...
1
vote
0answers
31 views

Donut-shaped / inverse mask in Phaser

I am trying to get a donut-shaped mask in Phaser (essentially the inverse of a regular mask). The mask shape is dynamic so it needs to be a Phaser.Graphics polygon object. Desired result: The blue ...
0
votes
1answer
633 views

Creating looping canvas animation (slot machine with reels)

I have a small assignment to create something like slot machine with spinning pictures. I have to use HTML5 Canvas. I would like to hear some opinions how this can be made simply and performantly. ...
3
votes
1answer
6k 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 ...
0
votes
0answers
65 views

UV texture mapping with perspective correction works for 50%

So, I've been trying to get the UV texture mapping down with perspective correction. The triangle rasterization seems to work. The interpolation seems to work too. It's just the perspective ...
2
votes
1answer
80 views

Tiled - move all tiles

I'm making a map in Tiled. I quickly ran out of room in the north of my map and would like to "shift" the tiles down. I'd prefer not to have to redo each of the tile layers. Is this possible? This ...
1
vote
1answer
45 views

Why can't CSS Sprites handle vectors?

Almost all the documentation available either says that "sprites are bitmaps" or that "css sprites must be bitmaps". Is there a specific reason for this? Is it, in fact possible to create a css sprite ...
0
votes
0answers
370 views

How to draw my android Hexagons in a grid?

I am trying to create a hexagon grid using the Android ’Canvas’ package. I have a working ’Hexagon’ class that when used in a view will draw a single hexagon on screen. The problem is that I need many ...
4
votes
1answer
252 views

Roguelike 2D Collision Detection

I'm just a normal guy trying to do some basic collision detection but I suck at it. I either get stuck in a wall or I go in reverse in the wrong direction trying to update the player position to a non ...
-1
votes
1answer
126 views

Adding obstacles & collision to canvas game

I am trying to add some obstacles to the canvas game that I've got but something seems to be wrong and I can't seem to put my finger on it. I just want some simple walls here and there to make the ...
1
vote
1answer
146 views

svg spaceship game movement 2d

I've been searching for a way to make an svg box move to all directions using js. I have seen many tutorials on how to do it grid like, but I want it so have a square that can turn, move forward, ...
2
votes
2answers
5k views

Android: Improving surfaceView?

I'm using Surfaceview in my Android app. I have two threads, one for UI and another for rendering and updading the UI. I am limiting my frames per second to 30 fps and have employed frame-skipping ...