conform: check we invalidate ancestor cached state

In the cases where we cache vertex state with an ancestor pipeline (whose
vertex processing state is equivalent) we need to invalidate that state
if that ancestor is later modified.

This conformance test checks this case but currently fails because we
only notify the progend directly associated with the pipeline being
changed.

In this case the pipeline can be using a different progend to the
ancestor which it is caching state with so when the ancestor is changed
it needs to notify all the progends that they may need to clear their
private state.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
(cherry picked from commit e112af5f770d6c46688fdcb5ba38b75ca0778891)

tests/conform/Makefile.am

@@ -66,6 +66,7 @@ test_sources = \
 	test-copy-replace-texture.c \
 	test-pipeline-cache-unrefs-texture.c \
 	test-texture-no-allocate.c \
+	test-pipeline-shader-state.c \
 	$(NULL)
 
 if !USING_EMSCRIPTEN

tests/conform/test-conform-main.c

@@ -131,6 +131,7 @@ main (int argc, char **argv)
   ADD_TEST (test_copy_replace_texture, 0, 0);
 
   ADD_TEST (test_pipeline_cache_unrefs_texture, 0, 0);
+  ADD_TEST (test_pipeline_shader_state, TEST_REQUIREMENT_GLSL, 0);
 
   UNPORTED_TEST (test_viewport);
 

tests/conform/test-pipeline-shader-state.c

@@ -0,0 +1,94 @@
+#include <cogl/cogl.h>
+
+#include <string.h>
+
+#include "test-utils.h"
+
+void
+test_pipeline_shader_state (void)
+{
+  CoglOffscreen *offscreen;
+  CoglFramebuffer *fb;
+  CoglPipeline *base_pipeline;
+  CoglPipeline *draw_pipeline;
+  CoglTexture2D *tex;
+  CoglSnippet *snippet;
+
+  float width = cogl_framebuffer_get_width (test_fb);
+  float height = cogl_framebuffer_get_height (test_fb);
+
+  cogl_framebuffer_orthographic (test_fb,
+                                 0, 0, width, height,
+                                 -1,
+                                 100);
+
+  tex = cogl_texture_2d_new_with_size (test_ctx,
+                                       128, 128, COGL_PIXEL_FORMAT_ANY);
+  offscreen = cogl_offscreen_new_with_texture (COGL_TEXTURE (tex));
+  fb = COGL_FRAMEBUFFER (offscreen);
+  cogl_framebuffer_clear4f (fb, COGL_BUFFER_BIT_COLOR, 0, 0, 0, 1);
+  cogl_object_unref (offscreen);
+
+  cogl_framebuffer_clear4f (test_fb, COGL_BUFFER_BIT_COLOR, 1, 1, 0, 1);
+
+
+  /* Setup a template pipeline... */
+
+  base_pipeline = cogl_pipeline_new (test_ctx);
+  cogl_pipeline_set_layer_texture (base_pipeline, 1, COGL_TEXTURE (tex));
+  cogl_pipeline_set_color4f (base_pipeline, 1, 0, 0, 1);
+
+
+  /* Derive a pipeline from the template, making a change that affects
+   * fragment processing but making sure not to affect vertex
+   * processing... */
+
+  draw_pipeline = cogl_pipeline_copy (base_pipeline);
+  snippet = cogl_snippet_new (COGL_SNIPPET_HOOK_FRAGMENT,
+                              NULL, /* declarations */
+                              "cogl_color_out = vec4 (0.0, 1.0, 0.1, 1.1);");
+  cogl_pipeline_add_snippet (draw_pipeline, snippet);
+  cogl_object_unref (snippet);
+
+  cogl_framebuffer_draw_rectangle (test_fb, draw_pipeline,
+                                   0, 0, width, height);
+
+  cogl_object_unref (draw_pipeline);
+
+  cogl_framebuffer_finish (test_fb);
+
+
+  /* At this point we should have provoked cogl to cache some vertex
+   * shader state for the draw_pipeline with the base_pipeline because
+   * none of the changes made to the draw_pipeline affected vertex
+   * processing. (NB: cogl will cache shader state with the oldest
+   * ancestor that the state is still valid for to maximize the chance
+   * that it can be used with other derived pipelines)
+   *
+   * Now we make a change to the base_pipeline to make sure that this
+   * cached vertex shader gets invalidated.
+   */
+
+  cogl_pipeline_set_layer_texture (base_pipeline, 0, COGL_TEXTURE (tex));
+
+
+  /* Now we derive another pipeline from base_pipeline to verify that
+   * it doesn't end up re-using the old cached state
+   */
+
+  draw_pipeline = cogl_pipeline_copy (base_pipeline);
+  snippet = cogl_snippet_new (COGL_SNIPPET_HOOK_FRAGMENT,
+                              NULL, /* declarations */
+                              "cogl_color_out = vec4 (0.0, 0.0, 1.1, 1.1);");
+  cogl_pipeline_add_snippet (draw_pipeline, snippet);
+  cogl_object_unref (snippet);
+
+  cogl_framebuffer_draw_rectangle (test_fb, draw_pipeline,
+                                   0, 0, width, height);
+
+  cogl_object_unref (draw_pipeline);
+
+
+  test_utils_check_region (test_fb, 0, 0, width, height,
+                           0x0000ffff);
+}