public void applyMatrix(float n00, float n01, float n02, float n03,
                            float n10, float n11, float n12, float n13,
                            float n20, float n21, float n22, float n23,
                            float n30, float n31, float n32, float n33) {
      showDepthWarningXYZ("applyMatrix");
    }


    /**
     * Loads the current matrix into m00, m01 etc (or modelview and
     * projection when using 3D) so that the values can be read.
     * <P/>
     * Note that there is no "updateMatrix" because that gets too
     * complicated (unnecessary) when considering the 3D matrices.
     */
//    public void loadMatrix() {
      // no-op on base PGraphics because they're used directly
//    }