mutter/tests/conform/test-blend.c
Robert Bragg f4fd724caf conform: Add color attribute based blending test
This adds a test to make sure that if the same pipeline is used to draw
two primitives, one which doesn't need blending because it has an opaque
color associated, and another using a color attribute that requires
blending then Cogl should recognize that it needs to enable blending for
the second primitive even though the pipeline hasn't changed.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit c15d91f1c6293bebd4494d1e20586121483cddef)
2013-06-06 21:27:16 +01:00

65 lines
2.0 KiB
C

#include <cogl/cogl.h>
#include <string.h>
#include "test-utils.h"
static void
paint (void)
{
CoglPipeline *pipeline = cogl_pipeline_new (test_ctx);
int width = cogl_framebuffer_get_width (test_fb);
int half_width = width / 2;
int height = cogl_framebuffer_get_height (test_fb);
CoglVertexP2 tri0_vertices[] = {
{ 0, 0 },
{ 0, height },
{ half_width, height },
};
CoglVertexP2C4 tri1_vertices[] = {
{ half_width, 0, 0x80, 0x80, 0x80, 0x80 },
{ half_width, height, 0x80, 0x80, 0x80, 0x80 },
{ width, height, 0x80, 0x80, 0x80, 0x80 },
};
CoglPrimitive *tri0;
CoglPrimitive *tri1;
cogl_framebuffer_clear4f (test_fb, COGL_BUFFER_BIT_COLOR, 0, 0, 0, 0);
tri0 = cogl_primitive_new_p2 (test_ctx, COGL_VERTICES_MODE_TRIANGLES,
3, tri0_vertices);
tri1 = cogl_primitive_new_p2c4 (test_ctx, COGL_VERTICES_MODE_TRIANGLES,
3, tri1_vertices);
/* Check that cogl correctly handles the case where we draw
* different primitives same pipeline and switch from using the
* opaque color associated with the pipeline and using a colour
* attribute with an alpha component which implies blending is
* required.
*
* If Cogl gets this wrong then then in all likelyhood the second
* primitive will be drawn with blending still disabled.
*/
cogl_framebuffer_draw_primitive (test_fb, pipeline, tri0);
cogl_framebuffer_draw_primitive (test_fb, pipeline, tri1);
test_utils_check_pixel_and_alpha (test_fb,
half_width + 5,
height - 5,
0x80808080);
}
void
test_blend (void)
{
cogl_framebuffer_orthographic (test_fb, 0, 0,
cogl_framebuffer_get_width (test_fb),
cogl_framebuffer_get_height (test_fb),
-1,
100);
paint ();
}