kutuluk/js13k-2d

A 2kb webgl 2d sprite renderer, designed for Js13kGames

js13k-2d's Issues

Hardcoded OpenGL constants?

What is the point of using plain integers for representing some if not all of the used OpenGL constants such as GL_TEXTURE_WRAP_S ?

Example: https://github.com/kutuluk/js13k-2d/blob/master/src/renderer.js#L123

I don't know much about WebGL, but if there's a chance that they might not be defined on some weird browsers or something, I think the right thing to do would maybe be to inject the values manually to the gl object in that case?

Using plain integers like that is very confusing.

How do you set the sprite width/height

I see there is a scale property, but can I directly specify the size?

Texture size must always be power of 2

Code sample:

    import Renderer from 'js13k-2d'

    const scene = Renderer(canvas, { alpha: true })

    scene.background(0, 1, 0, 0.2)
    const atlas = scene.texture(createImageTexture(img), 0)
    const frame = atlas.frame(Renderer.Point(), atlas.size, Renderer.Point(0.5, 0.5))
    const sprites = []
    for (let i = 0; i < 0; i++) {
      const sprite = Renderer.Sprite(frame)
      sprite.rotation = Math.random() * 2 * Math.PI
      sprite.tint = Math.random() * 0xff0000
      scene.add(sprite)
      sprites.push(sprite)
    }
    scene.resize()
    scene.render()

Actual img size is (125px, 81px), so I need to use helper function createImageTexture

const createImageTexture = (img) => {
  const canvas = document.createElement('canvas')
  canvas.width = 1 << Math.ceil(Math.log2(img.width)) // eslint-disable-line
  canvas.height = 1 << Math.ceil(Math.log2(img.height)) // eslint-disable-line
  canvas.getContext('2d').drawImage(img, 0, 0)

  return canvas
}

Proper error handling?

Why are all the existing error checks commented out at the moment?

Example: https://github.com/kutuluk/js13k-2d/blob/master/src/renderer.js#L37

If an error occurs with for example OpenGL, I think it should be treated somehow by the lib so that the user of the library can catch it.