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WebGL Utility
All those other WebGL libraries are far too abstracted. Perfect if you don't like prying under the hood. Not so great if you do.

I made my own minimalist bindings to WebGL. Taking advantages of objects, dynamic types, and all those other things that the original OpenGL couldn't support.

Of course I also have a Lua version. It's here. I don't have any code that uses it posted at the moment. Maybe later that will change.


Here's the GitHub

GLUtil class

GLUtil.prototype.onload
Array of functions to call upon creation of a GLUtil object. Each function is called with 'this' set to the GLUtil object.

GLUtil.prototype.webGLNames
List of names to query WebGL use for using the HTML canvas getContext function.

GLUtil objects

glutil = new GLUtil(args)
args:
canvas = the HTML canvas object to use.
canvasArgs = arguments to pass to to the getContext function of the canvas.
By default the following arguments are set to canvasArgs:
premultipliedAlpha is set to false
alpha is set to false

glutil.canvas
The canvas of the GLUtil object.

glutil.context
The WebGL context of the canvas.

glutil.wrapMap
An object mapping letters 's' and 't' to WebGL constants TEXTURE_WRAP_S and TEXTURE_WRAP_T.

glutil.fragmentPrecision
The default precision code to prepend to fragment shaders.

glutil.vertexPrecision
The default precision code to prepend to vertex shaders.

view = new glutil.View(args)
args:
zNear = (optional) default 1
zFar = (optional) default 2000
fovY = (optional) default 90
ortho = (optional) orthogonal view. default false.
pos = (optional) [x,y,z]. default [0,0,0].
angle = (optional) [x,y,z,w] quaternion. default [0,0,0,1].

view.zNear the near plane of the View.
view.zFar the far plane of the View.
view.fovY the fov along the vertical of the View.
view.ortho whether the View is orthogonal or frustum.
view.pos the View position, as [x,y,z].
view.angle the View angle quaternion, as [x,y,z,w].

scene = new glutil.Scene()

scene.projMat the projection matrix associated with this Scene.
Computation comes from the View projection variables (zNear, zFar, fovY, ortho) and the canvas width and height.

scene.mvMat the modelview matrix associated with this Scene.
Computation starts as the inverse transform of the View translation (of view.pos) and rotation (of view.angle).
It is subsequently permuted as the scene graph is traversed.

scene.setupMatrices()
Initializes the scene.projMat and scene.mvMat.

shader = new glutil.Shader(args)
args:
code = (optional) shader code to use.
id = (optional) the id of a DOM object to use the text of.
Shader is an abstract class which depends on its shaderType field to be defined.

shader.obj = the WebGL createShader object.

vertexShader = new glutil.VertexShader(args)
args are passed on to Shader construction.

VertexShader.prototype.shaderType is initialized to the context constant VERTEX_SHADER.

FragmentShader.prototype.shaderType is initialized to the context constant FRAGMENT_SHADER.

shaderProgram = new glutil.ShaderProgram(args)
args:
one of the following:
vertexShader = the VertexShader object to link with.
vertexCode = the vertex shader code.
vertexCodeID = this DOM element id containing vertex shader code.
and one of the following:
fragmentShader = the FragmentShader object to link with.
fragmentCode = the fragment shader code.
fragmentCodeID = the DOM element id containing fragment shader code.
optional:
vertexPrecision = set to 'best' to prepend the 'using precision' code for the the highest supported precision.
fragmentPrecision = set to 'best' to prepend the 'using precision' code for the highest supported precision.
uniforms: a key/value map containing initial values of any uniforms.

shaderProgram.vertexShader = the ShaderProgram's VertexShader.
shaderProgram.fragmentShader = the ShaderProgram's FragmentShader.
shaderProgram.obj = the WebGL createProgram object.

shaderProgram.uniforms = a map from both each uniform's name and each uniform's index to its WebGL getActiveUniform structure.
This object also has the following fields appended:
shaderProgram.uniforms[i].loc = the WebGL getUniformLocation for this uniform.
shaderProgram.uniforms[i].setters = an object containing the following fields:
count : the number of elements in the uniform setter.
arg : the WebGL uniform setter accepting primitives
vec : the WebGL uniform setter accepting an array
mat : the WebGL uniform setter accepting a matrix

shaderProgram.attrs = a map from both each attribute's name and each attribute's index to its WebGL getActiveAttrib structure.
This object also has the following fields appended:
shaderProgram.attrs[i].loc = the WebGL getAttribLocation for this attribute.

shaderProgram.use() enables this ShaderProgram. Returns self.
shaderProgram.useNone() disables this ShaderProgram. Returns self.

shaderProgram.setUniforms(uniforms) calls shaderProgram.setUniform on all key/value pairs in 'uniforms.' Returns self.

TODO Texture, Texture2D, ArrayBuffer, ElementArrayBuffer, Framebuffer, Geometry, Attribute, SceneObject