tribPointer(1, 4, gl.UNSIGNED_BYTE, false, 0, 0);
    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "after texture coordinate / color redefinition");

    var numQuads = 2;
    var indices = new Uint32Array(numQuads * 6);
    for (var ii = 0; ii < numQuads; ++ii) {
        var offset = ii * 6;
        var quad = (ii == (numQuads - 1)) ? 4 : 0;
        indices[offset + 0] = quad + 0;
        indices[offset + 1] = quad + 1;
        indices[offset + 2] = quad + 2;
        indices[offset + 3] = quad + 2;
        indices