Add a conformance test for some wrap modes on a rectangle texture

This adds a conformance test which renders a rectangle texture using
the two wrap modes clamp-to-edge and repeat. It then verifies that the
correct region of the texture is drawn for the texture coordinates
that are > 1.0.

The test currently always fails. The cogl_framebuffer_draw_rectangle
function is documented to always take normalized texture coordinates
regardless of the coordinate system of the texture. This works
correctly if all of the texture coordinates are in the range [0.0,1.0]
because cogl-primitives uses a different code path in that case.
However if the multiple-quad code path is taken then the coordinates
actually need to un-normalized for it to work.

There is a comment in cogl_meta_texture_foreach_in_region() which
implies that the incoming coordinates should always be normalized.
The documentation for the callback says that the resulting sub-texture
coordinates will always be in the coordinate system of the low-level
texture. However it doesn't work out like this because the meta
texture function uses the span iterating function which always returns
normalized coordinates. It looks like there needs to be some more
conversions going on somewhere.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit d2059bb32b8015060e10f41dbbb68d4230b47ddb)

tests/conform/Makefile.am

@@ -60,6 +60,7 @@ test_sources = \
 	test-map-buffer-range.c \
 	test-npot-texture.c \
 	test-alpha-textures.c \
+	test-wrap-rectangle-textures.c \
 	test-texture-get-set-data.c \
 	$(NULL)
 

tests/conform/test-conform-main.c

@@ -80,6 +80,9 @@ main (int argc, char **argv)
   ADD_TEST (test_read_texture_formats, 0, 0);
   ADD_TEST (test_write_texture_formats, 0, 0);
   ADD_TEST (test_alpha_textures, 0, 0);
+  ADD_TEST (test_wrap_rectangle_textures,
+            TEST_REQUIREMENT_TEXTURE_RECTANGLE,
+            TEST_KNOWN_FAILURE);
 
   UNPORTED_TEST (test_vertex_buffer_contiguous);
   UNPORTED_TEST (test_vertex_buffer_interleved);

tests/conform/test-utils.c

@@ -35,6 +35,12 @@ check_flags (TestFlags flags,
       return FALSE;
     }
 
+  if (flags & TEST_REQUIREMENT_TEXTURE_RECTANGLE &&
+      !cogl_has_feature (test_ctx, COGL_FEATURE_ID_TEXTURE_RECTANGLE))
+    {
+      return FALSE;
+    }
+
   if (flags & TEST_REQUIREMENT_POINT_SPRITE &&
       !cogl_has_feature (test_ctx, COGL_FEATURE_ID_POINT_SPRITE))
     {

tests/conform/test-utils.h

@@ -15,10 +15,11 @@ typedef enum _TestFlags
   TEST_REQUIREMENT_GL = 1<<1,
   TEST_REQUIREMENT_NPOT = 1<<2,
   TEST_REQUIREMENT_TEXTURE_3D = 1<<3,
-  TEST_REQUIREMENT_POINT_SPRITE  = 1<<4,
+  TEST_REQUIREMENT_TEXTURE_RECTANGLE = 1<<4,
-  TEST_REQUIREMENT_GLES2_CONTEXT = 1<<5,
+  TEST_REQUIREMENT_POINT_SPRITE = 1<<5,
-  TEST_REQUIREMENT_MAP_WRITE     = 1<<6,
+  TEST_REQUIREMENT_GLES2_CONTEXT = 1<<6,
-  TEST_REQUIREMENT_GLSL          = 1<<7
+  TEST_REQUIREMENT_MAP_WRITE = 1<<7,
+  TEST_REQUIREMENT_GLSL = 1<<8
 } TestFlags;
 
 extern CoglContext *test_ctx;

tests/conform/test-wrap-rectangle-textures.c

@@ -0,0 +1,179 @@
+#include <cogl/cogl.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+
+#include <string.h>
+
+#include "test-utils.h"
+
+#define DRAW_SIZE 64
+
+static CoglPipeline *
+create_base_pipeline (void)
+{
+  CoglBitmap *bmp;
+  CoglTextureRectangle *tex;
+  CoglPipeline *pipeline;
+  uint8_t tex_data[] =
+    {
+      0x44, 0x44, 0x44, 0x88, 0x88, 0x88,
+      0xcc, 0xcc, 0xcc, 0xff, 0xff, 0xff
+    };
+
+  bmp = cogl_bitmap_new_for_data (test_ctx,
+                                  2, 2, /* width/height */
+                                  COGL_PIXEL_FORMAT_RGB_888,
+                                  2 * 3, /* rowstride */
+                                  tex_data);
+
+  tex = cogl_texture_rectangle_new_from_bitmap (bmp,
+                                                /* internal format */
+                                                COGL_PIXEL_FORMAT_ANY,
+                                                NULL);
+
+  cogl_object_unref (bmp);
+
+  pipeline = cogl_pipeline_new (test_ctx);
+
+  cogl_pipeline_set_layer_filters (pipeline,
+                                   0, /* layer */
+                                   COGL_PIPELINE_FILTER_NEAREST,
+                                   COGL_PIPELINE_FILTER_NEAREST);
+
+  cogl_pipeline_set_layer_texture (pipeline,
+                                   0, /* layer */
+                                   COGL_TEXTURE (tex));
+
+  cogl_object_unref (tex);
+
+  return pipeline;
+}
+
+static void
+check_colors (int x_offset,
+              int y_offset,
+              const uint8_t expected_colors[9])
+{
+  int x, y;
+
+  for (y = 0; y < 4; y++)
+    for (x = 0; x < 4; x++)
+      {
+        uint32_t color = expected_colors[x + y * 4];
+        test_utils_check_region (test_fb,
+                                 x * DRAW_SIZE / 4 + 1 + x_offset,
+                                 y * DRAW_SIZE / 4 + 1 + y_offset,
+                                 DRAW_SIZE / 4 - 2,
+                                 DRAW_SIZE / 4 - 2,
+                                 0xff |
+                                 (color << 8) |
+                                 (color << 16) |
+                                 (color << 24));
+      }
+}
+
+static void
+test_pipeline (CoglPipeline *pipeline,
+               int x_offset,
+               int y_offset,
+               const uint8_t expected_colors[9])
+{
+  float x1 = x_offset;
+  float y1 = y_offset;
+  float x2 = x1 + DRAW_SIZE;
+  float y2 = y1 + DRAW_SIZE;
+  int y, x;
+
+  cogl_framebuffer_draw_textured_rectangle (test_fb,
+                                            pipeline,
+                                            x1, y1,
+                                            x2, y2,
+                                            -0.5f, /* s1 */
+                                            -0.5f, /* t1 */
+                                            1.5f, /* s2 */
+                                            1.5f /* t2 */);
+
+  check_colors (x_offset, y_offset, expected_colors);
+
+  /* Also try drawing each quadrant of the rectangle with a small
+   * rectangle */
+
+  for (y = -1; y < 3; y++)
+    for (x = -1; x < 3; x++)
+      {
+        x1 = x_offset + (x + 1) * DRAW_SIZE / 4 + DRAW_SIZE;
+        y1 = y_offset + (y + 1) * DRAW_SIZE / 4;
+        x2 = x1 + DRAW_SIZE / 4;
+        y2 = y1 + DRAW_SIZE / 4;
+
+        cogl_framebuffer_draw_textured_rectangle (test_fb,
+                                                  pipeline,
+                                                  x1, y1,
+                                                  x2, y2,
+                                                  x / 2.0f, /* s1 */
+                                                  y / 2.0f, /* t1 */
+                                                  (x + 1) / 2.0f, /* s2 */
+                                                  (y + 1) / 2.0f /* t2 */);
+      }
+
+  check_colors (x_offset + DRAW_SIZE, y_offset, expected_colors);
+}
+
+void
+test_wrap_rectangle_textures (void)
+{
+  float fb_width = cogl_framebuffer_get_width (test_fb);
+  float fb_height = cogl_framebuffer_get_height (test_fb);
+  CoglPipeline *base_pipeline;
+  CoglPipeline *clamp_pipeline;
+  CoglPipeline *repeat_pipeline;
+  /* The textures are drawn with the texture coordinates from
+   * -0.5→1.5. That means we get one complete copy of the texture and
+   * an extra half of the texture surrounding it. The drawing is
+   * tested against a 4x4 grid of colors. The center 2x2 colours
+   * specify the normal texture colors and the other colours specify
+   * what the wrap mode should generate */
+  static const uint8_t clamp_colors[] =
+    {
+      0x44, 0x44, 0x88, 0x88,
+      0x44, 0x44, 0x88, 0x88,
+      0xcc, 0xcc, 0xff, 0xff,
+      0xcc, 0xcc, 0xff, 0xff
+    };
+  static const uint8_t repeat_colors[] =
+    {
+      0xff, 0xcc, 0xff, 0xcc,
+      0x88, 0x44, 0x88, 0x44,
+      0xff, 0xcc, 0xff, 0xcc,
+      0x88, 0x44, 0x88, 0x44
+    };
+
+  cogl_framebuffer_orthographic (test_fb,
+                                 0, 0, /* x_1, y_1 */
+                                 fb_width, /* x_2 */
+                                 fb_height /* y_2 */,
+                                 -1, 100 /* near/far */);
+
+  base_pipeline = create_base_pipeline ();
+
+  clamp_pipeline = cogl_pipeline_copy (base_pipeline);
+  cogl_pipeline_set_layer_wrap_mode (clamp_pipeline,
+                                     0, /* layer */
+                                     COGL_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE);
+
+  repeat_pipeline = cogl_pipeline_copy (base_pipeline);
+  cogl_pipeline_set_layer_wrap_mode (repeat_pipeline,
+                                     0, /* layer */
+                                     COGL_PIPELINE_WRAP_MODE_REPEAT);
+
+  test_pipeline (clamp_pipeline,
+                 0, 0, /* x/y offset */
+                 clamp_colors);
+
+  test_pipeline (repeat_pipeline,
+                 0, DRAW_SIZE * 2, /* x/y offset */
+                 repeat_colors);
+
+  cogl_object_unref (repeat_pipeline);
+  cogl_object_unref (clamp_pipeline);
+  cogl_object_unref (base_pipeline);
+}