FER, new Float32Array([
        -1,1,0, 1,1,0, -1,-1,0, 1,-1,0,
        -1,1,0, 1,1,0, -1,-1,0, 1,-1,0]), drawType);
    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "after vertex redefinition");
    gl.bindBuffer(gl.ARRAY_BUFFER, texCoordObject);
    gl.bufferData(gl.ARRAY_BUFFER, new Uint8Array([
        255, 0, 0, 255,
        255, 0, 0, 255,
        255, 0, 0, 255,
        255, 0, 0, 255,
        0, 255, 0, 255,
        0, 255, 0, 255,
        0, 255, 0, 255,
        0, 255, 0, 255]), drawType);
    gl.vertexAt