000-hellotriangle

VBOs

Vertex attributes are views into the VBO, which may be much larger than the data that is interesting to the renderer.

glVertexAttribPointer behaviour

This function is quite counter intuitive, even when one has a good grasp on pointers, structs and offsets.

TODO: I still don't understand why the heck I'm calling

gl.VertexAttribPointerWithOffset(vertAttrib, 2, gl.FLOAT, false, 2*attrSize, 0)

With size=2... Why? My best guess is that each "vertex" is composed of two gl.FLOAT's, so the size of the vertex is 2? This may be related to the DrawArrays call which takes a count parameter. Which is 3:

// Inside render loop...
gl.DrawArrays(gl.TRIANGLES, 0, 3)

So maybe DrawArrays iterates over the array with the following loop condition(?):

iLimit := size*count

for i:=first; i < iLimit; i++ {
    offset := i*stride + first
    // ...
}