vgSeti(VG_RENDERING_QUALITY, VG_RENDERING_QUALITY_BETTER);
vgSeti(VG_IMAGE_QUALITY, VG_IMAGE_QUALITY_BETTER);
vgSeti(VG_BLEND_MODE, VG_BLEND_SRC_OVER);
vgSeti(VG_SCISSORING, VG_FALSE);
vgSeti(VG_MASKING, VG_FALSE);
vgSeti(VG_IMAGE_MODE, VG_DRAW_IMAGE_NORMAL);
col[0] = 1.0f; col[1] = 1.0f; col[2] = 1.0f; col[3] = 1.0f;
vgSetfv(VG_CLEAR_COLOR, 4, col);
vgClear(0, 0, 256, 256);

// create draw image and load external data
img = vgCreateImage(imgGirlFormat, imgGirlWidth, imgGirlHeight, VG_IMAGE_QUALITY_FASTER);
vgImageSubData(img, (const void *)&imgGirlData[imgGirlWidth * (imgGirlHeight - 1)], -imgGirlDataStride, imgGirlFormat, 0, 0, imgGirlWidth, imgGirlHeight);

vguComputeWarpSquareToQuad(50.0f / 256.0f, 50.2f / 256.0f,
							250.0f / 256.0f, 80.0f / 256.0f,
							80.0f / 256.0f, 250.0f / 256.0f,
							280.0f / 256.0f, 280.0f / 256.0f,
							matrix);
							
vgSeti(VG_MATRIX_MODE, VG_MATRIX_IMAGE_USER_TO_SURFACE);
vgLoadMatrix(matrix);
vgDrawImage(img);

saveDrawingSurface(f, "draw_vgu_warpsquaretoquad.png", "Test VGU vguComputeWarpSquareToQuad function.", 0, 0, 256, 256);
eglSwapBuffers(display, surface);
	
vgDestroyImage(img);