WebGL：数据转换为非方形alpha纹理

Question

I have a weird problem with webGL.

I'm using a dynamically generated texture of which only the alpha channel matters. Here's the code:

var texture  = new Uint8Array(ar); // ar is my array
gl.bindTexture(gl.TEXTURE_2D, this.transparencyTexture);
gl.texImage2D(gl.TEXTURE_2D, 0, gl.ALPHA, array.length, array[0].length, 0, gl.ALPHA, gl.UNSIGNED_BYTE, texture);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);   

I'm always using a POT array' "width" and "height" but whenever "width" <> "height" it doesn't work. So it currently only works with squares.

What can be done?

EDIT:

http://jsfiddle.net/SergeJcqmn/EAmjU/9/

Answer 1

In the jsfiddle, line 76 of the js is incorrect:

ar.push(array[x][(array.length - 1) - y] ?  128 : 0);

I believe this should be:

ar.push(array[x][(array[0].length - 1) - y] ?  128 : 0);