Gets the test passing for cases with low resolution, high amount of triangles and more than one glDrawRangeElements (drawing_passes). ---
Just to catch attention, this issue also affects the failing CTS test GL44-CTS.texture_barrier_ARB.same-texel-rw-multipass on Intel gen7+. And sorry for the cross-posting, but usually questions related about specs are more suited for mesa-dev. The test I have just sent to piglit list fails in the following scenario: * Low resolution * High amount of triangles on the square draw * More than one glDrawRangeElements to render the square. As this patch shows, the problem gets solved if I move the glTextureBarrier call just after glDrawRangeElements, instead of having it after each full square drawn. But Im not sure if this should be needed if we strictly follow the spec. The spec [1] even include a example of when the barrier would not be needed on Issue 1. If what you are drawing doesn't intersect to what you have been drawing before, you don't need to call glTextureBarrier. Being strict, the test is drawing non intersecting elements, as the triangles are independent one from the other. But it is also true that this is somewhat debatable as the borders of the triangles are shared, so with low resolution and a high amount of triangles it can cause these artifacts. So, opinions? Is this patch correct so the problem was on the piglit test? Or this patch should not be needed so the problem is on the implementation of arb_texture_barrier? [1] https://www.opengl.org/registry/specs/ARB/texture_barrier.txt tests/spec/arb_texture_barrier/blending-in-shader-arb.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/tests/spec/arb_texture_barrier/blending-in-shader-arb.c b/tests/spec/arb_texture_barrier/blending-in-shader-arb.c index 76822da..c84cfaf 100644 --- a/tests/spec/arb_texture_barrier/blending-in-shader-arb.c +++ b/tests/spec/arb_texture_barrier/blending-in-shader-arb.c @@ -318,6 +318,7 @@ draw_rect_tex() glDrawRangeElements(GL_TRIANGLES, first, first + count, count, GL_UNSIGNED_INT, BUFFER_OFFSET(first * sizeof(GLuint))); + glTextureBarrier(); first += count; } } @@ -330,8 +331,6 @@ piglit_display(void) glViewport(0, 0, width, height); for (i = 0; i < blend_passes; i++) { - if (i != 0) - glTextureBarrier(); draw_rect_tex(); } -- 2.7.4 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
