gl-texture2d-read-float


Read out the contents of a floating-point
gl-texture2d.

This will eventually be supported natively in WebGL
(it's listed in the OpenGL ES 3 spec),
but this fills that need until then!

Usage


$3

Reads out the contents of glTex2d, which should be an instance of
gl-texture2d. When complete, done(err, data) will be called where data is
a Float32Array containing the resulting floats in the texture.

`` javascript
const canvas = document.createElement('canvas')
const gl = require('gl-context')(canvas)

const read = require('gl-texture2d-read-float')
const Texture2d = require('gl-texture2d')
const baboon = require('baboon-image')
const assert = require('assert')

const texture = baboon(gl, baboon)

read(texture, function(err, data) {
if (err) throw err

assert.deepEqual(data, baboon.data)
})
`

A few things to note:

* Right now, this is slow as it requires reading data back from the GPU.
There's not much that can be done about this for the time being unfortunately.
* The data is retrieved synchronously under the hood, but the API has been made
asynchronous in preparation for WebGL's eventual async readPixels equivalent.
* Only gl.RGBA/gl.FLOAT` textures are currently supported. Pull requests are,
however, very welcome! :)

Contributing

See stackgl/contributing for details.

License

MIT. See LICENSE.md for details.