[Cogl] [PATCH] conform: check we invalidate ancestor cached state

[Robert Bragg]

From: Robert Bragg <robert at linux.intel.com>

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.
---
 tests/conform/Makefile.am                  |  1 +
 tests/conform/test-conform-main.c          |  1 +
 tests/conform/test-pipeline-shader-state.c | 94 ++++++++++++++++++++++++++++++
 3 files changed, 96 insertions(+)
 create mode 100644 tests/conform/test-pipeline-shader-state.c

diff --git a/tests/conform/Makefile.am b/tests/conform/Makefile.am
index 5678630..633507a 100644
--- a/tests/conform/Makefile.am
+++ b/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
diff --git a/tests/conform/test-conform-main.c b/tests/conform/test-conform-main.c
index 56f93cf..047537b 100644
--- a/tests/conform/test-conform-main.c
+++ b/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);
 
diff --git a/tests/conform/test-pipeline-shader-state.c b/tests/conform/test-pipeline-shader-state.c
new file mode 100644
index 0000000..72d8138
--- /dev/null
+++ b/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_to_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_flush ();
+
+
+  /* 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);
+}
-- 
1.8.3.1