Consider this series of events:
glColorMask(GL_FALSE, GL_TRUE, GL_TRUE, GL_TRUE);
glClearColor(0.125f, 0.25f, 0.5f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
With virgl, this may render an incorrect result. This is because
there our two paths for clears in Gallium -- one for full clears
(st->pipe->clear) and another for color-masked/scissored clears
(clear_with_quad). We only encode the color mask in the
virgl_encode_blend_state in the clear_with_quad case.
We should set the colormask the case of full clears as well, since
we need to update the GL state on the host driver.
With this patch, the number of dEQP GLES2 failures on Virgl with a
nvidia host driver goes from 260 to 136 with no regressions.
Some representative test cases are:
dEQP-GLES2.functional.color_clear.masked_scissored_rgb
dEQP-GLES2.functional.color_clear.masked_scissored_rgba
dEQP-GLES2.functional.depth_stencil_clear.depth_stencil_scissored
dEQP-GLES2.functional.fragment_ops.random.0
dEQP-GLES2.functional.fragment_ops.interaction.basic_shader.0
v2: Revise comments, fix curly braces (Elie)
Signed-off-by: Dave Airlie <airlied@redhat.com>
Gurchetan Singh
252b00d77c