[cogl] test-just-vertex-shader: Sample a texture in the fragment pipeline

[Neil Roberts <nroberts src gnome org>]

commit 884647071cc375ec10f306400c3d72bcb81550a3
Author: Neil Roberts <neil linux intel com>
Date:   Wed Oct 19 11:04:51 2011 +0100

    test-just-vertex-shader: Sample a texture in the fragment pipeline
    
    Previously the layer combine on the test pipeline was set up to
    replace the incoming color with the layer constant. This patch changes
    it to sample the replacement color from a 1x1 texture instead. This
    exposes a bug on the GLES2 backend where the vertex shader will be
    generated with a size for cogl_tex_coord_out of 4 but the
    corresponding declaration in the fragment shader will have n_layers,
    which is 1. This makes the program fail to link and the test fails.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=662184
    
    Reviewed-by: Robert Bragg <robert linux intel com>

 tests/conform/test-just-vertex-shader.c |   41 +++++++++++++++++++++++-------
 1 files changed, 31 insertions(+), 10 deletions(-)
---
diff --git a/tests/conform/test-just-vertex-shader.c b/tests/conform/test-just-vertex-shader.c
index ead7d6c..91e05fd 100644
--- a/tests/conform/test-just-vertex-shader.c
+++ b/tests/conform/test-just-vertex-shader.c
@@ -9,10 +9,26 @@ typedef struct _TestState
   int dummy;
 } TestState;
 
+static CoglHandle
+create_dummy_texture (void)
+{
+  /* Create a dummy 1x1 green texture to replace the color from the
+     vertex shader */
+  static const guint8 data[4] = { 0x00, 0xff, 0x00, 0xff };
+
+  return cogl_texture_new_from_data (1, 1, /* size */
+                                     COGL_TEXTURE_NONE,
+                                     COGL_PIXEL_FORMAT_RGB_888,
+                                     COGL_PIXEL_FORMAT_ANY,
+                                     4, /* rowstride */
+                                     data);
+}
+
 static void
 paint_legacy (TestState *state)
 {
   CoglHandle material = cogl_material_new ();
+  CoglHandle tex;
   CoglColor color;
   GError *error = NULL;
   CoglHandle shader, program;
@@ -25,14 +41,15 @@ paint_legacy (TestState *state)
   cogl_material_set_color (material, &color);
 
   /* Override the vertex color in the texture environment with a
-     constant green color */
-  cogl_color_set_from_4ub (&color, 0x00, 0xff, 0x00, 0xff);
-  cogl_material_set_layer_combine_constant (material, 0, &color);
+     constant green color provided by a texture */
+  tex = create_dummy_texture ();
+  cogl_material_set_layer (material, 0, tex);
+  cogl_handle_unref (tex);
   if (!cogl_material_set_layer_combine (material, 0,
-                                        "RGBA=REPLACE(CONSTANT)",
+                                        "RGBA=REPLACE(TEXTURE)",
                                         &error))
     {
-      g_warning ("Error setting blend constant: %s", error->message);
+      g_warning ("Error setting layer combine: %s", error->message);
       g_assert_not_reached ();
     }
 
@@ -47,6 +64,7 @@ paint_legacy (TestState *state)
                       "cogl_modelview_projection_matrix * "
                       "cogl_position_in;\n"
                       "  cogl_color_out = cogl_color_in;\n"
+                      "  cogl_tex_coord_out[0] = cogl_tex_coord_in;\n"
                       "}\n");
   cogl_shader_compile (shader);
   if (!cogl_shader_is_compiled (shader))
@@ -80,6 +98,7 @@ static void
 paint (TestState *state)
 {
   CoglPipeline *pipeline = cogl_pipeline_new ();
+  CoglHandle tex;
   CoglColor color;
   GError *error = NULL;
   CoglHandle shader, program;
@@ -92,14 +111,15 @@ paint (TestState *state)
   cogl_pipeline_set_color (pipeline, &color);
 
   /* Override the vertex color in the texture environment with a
-     constant green color */
-  cogl_color_set_from_4ub (&color, 0x00, 0xff, 0x00, 0xff);
-  cogl_pipeline_set_layer_combine_constant (pipeline, 0, &color);
+     constant green color provided by a texture */
+  tex = create_dummy_texture ();
+  cogl_pipeline_set_layer_texture (pipeline, 0, tex);
+  cogl_handle_unref (tex);
   if (!cogl_pipeline_set_layer_combine (pipeline, 0,
-                                        "RGBA=REPLACE(CONSTANT)",
+                                        "RGBA=REPLACE(TEXTURE)",
                                         &error))
     {
-      g_warning ("Error setting blend constant: %s", error->message);
+      g_warning ("Error setting layer combine: %s", error->message);
       g_assert_not_reached ();
     }
 
@@ -114,6 +134,7 @@ paint (TestState *state)
                       "cogl_modelview_projection_matrix * "
                       "cogl_position_in;\n"
                       "  cogl_color_out = cogl_color_in;\n"
+                      "  cogl_tex_coord_out[0] = cogl_tex_coord_in;\n"
                       "}\n");
   cogl_shader_compile (shader);
   if (!cogl_shader_is_compiled (shader))