texHTMLElement should be texSubImage2D like, not texImage2D like or both should exist

[greggman]

texImage2D both allocates a mip level of a texture AND, optionally copies data into mip level.

texSubImage2D only copies data.

texSubImage2D is usable with immutable textures (textures created with texStorage2D). texImage2D is not. texStorage2D created textures can use less memory and be more efficient than texImage2D created textures.

You could have both texHTMLElement and texSubHTMLElement but if you're only going to have one, texHTMLElement can be implemented on top of texSubHTMLElement

Also, this appears to have the same issues as drawElement with regards to devicePixelRatio.