WebGL 'texture not renderable' warning logged, but all behaviour correct

Question

I'm authoring a WebGL app. Everything works as expected, except that I get the following error in the debug console.

[.WebGLRenderingContext-0086F710]RENDER WARNING: texture bound to texture unit 0 is not renderable. It maybe non-power-of-2 and have incompatible texture filtering.

Let's eliminate some possibilities

1- This is most certainly not a problem of texture loading as the textures show up correctly in the first frame.

2- I'm aware of usage of power-of-two textures, and that's what I do. Until I actually have relevant texture, I'm using the fill in texture below, except that one is scaled up, the one in use is 2x2.

2a- I understand that the incompatible texture filtering to which the warning refers is to go with non-power-of-two textures, but here's the relevant filtering code anyway.

// When creating the texture
var texture = gl.createTexture();
texture.image = new Image();
texture.image.onload = function() {
    gl.bindTexture(gl.TEXTURE_2D, texture);
    gl.pixelStorei(gl.UNPACK_FLIP_Y_WEBGL, true);
    gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, texture.image);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
    gl.generateMipmap(gl.TEXTURE_2D);
    gl.bindTexture(gl.TEXTURE_2D, null);
}
texture.image.src = src;

// At render time
gl.activeTexture(gl.TEXTURE0);
gl.bindTexture(gl.TEXTURE_2D, item.texture);
gl.uniform1i(gl.getUniformLocation(shaderProgram, "uSampler"), 0);

Am I correct in assuming that this error's guess at why it is occurring is wrong? What will satisfy (not just suppress) it?

Thanks in advance.

Is your "filler" texture loaded before your run the render loop? — LJᛃ
Yes. That's why, in my question, I said, 1- This is most certainly not a problem of texture loading as the textures show up correctly in the first frame. — Scruffy

gman gman · Accepted Answer · 2015-09-10T23:47:37

Do you render before your textures have finished loading? That's a common source of that error. My solution is to create a 1x1 pixel texture for each texture at creation time, then update it when the texture loads.

Add these lines

var texture = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, texture);
gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 1, 1, 0, gl.RGBA,
     gl.UNSIGNED_BYTE, new Uint8Array([255, 0, 0, 255]));

The other thing to check is that all uniforms default to zero if not initialized which means all samplers point to texture unit 0.

WebGL 'texture not renderable' warning logged, but all behaviour correct

1 Answers