pixel-array: Only allow allocation of arrays with a 2D size

This removes cogl_pixel_array_new which just took a size in bytes.

Without the image size and pixel format then the driver often doesn't
have enough information to allocate optimal GPU memory that can be
textured from directly. This is because GPUs often have ways to
spatially alter the layout of a texture to improve cache access patterns
which may require special alignment and padding dependant in the images
width, height and bpp.

Although currently we are limited by OpenGL because it doesn't let us
pass on the width and height when allocating a PBO, the hope is that we
can define a better extension at some point.

clutter/cogl/cogl/cogl-pixel-array.c

@@ -87,8 +87,8 @@ cogl_malloc_pixel_array_vtable;
 
 COGL_BUFFER_DEFINE (PixelArray, pixel_array)
 
-CoglPixelArray *
+static CoglPixelArray *
-cogl_pixel_array_new (unsigned int size)
+_cogl_pixel_array_new (unsigned int size)
 {
   CoglPixelArray *pixel_array = g_slice_new0 (CoglPixelArray);
   CoglBuffer *buffer = COGL_BUFFER (pixel_array);
@@ -148,7 +148,7 @@ cogl_pixel_array_new_with_size (unsigned int    width,
   if (rowstride)
     *rowstride = stride;
 
-  buffer = cogl_pixel_array_new (height * stride);
+  buffer = _cogl_pixel_array_new (height * stride);
   if (G_UNLIKELY (buffer == COGL_INVALID_HANDLE))
     return COGL_INVALID_HANDLE;
 

clutter/cogl/cogl/cogl-pixel-array.h

@@ -52,22 +52,6 @@ G_BEGIN_DECLS
 
 typedef struct _CoglPixelArray CoglPixelArray;
 
-/**
- * cogl_pixel_array_new:
- * @size: size of the array in bytes
- *
- * Creates a new array to store pixel data. You can create a new texture from
- * this array using cogl_texture_new_from_buffer().
- *
- * Return value: a #CoglPixelArray representing the newly created array or
- *               %NULL on failure
- *
- * Since: 1.2
- * Stability: Unstable
- */
-CoglPixelArray *
-cogl_pixel_array_new (unsigned int size);
-
 /**
  * cogl_pixel_array_new_with_size:
  * @width: width of the pixel array in pixels

tests/conform/test-cogl-pixel-buffer.c

@@ -62,8 +62,13 @@ create_map_tile (TestTile *tile)
   CoglHandle buffer;
   guchar *map;
   guint i;
+  unsigned int stride = 0;
+  guint8 *line;
 
-  buffer = cogl_pixel_array_new (TILE_SIZE * TILE_SIZE * 4);
+  buffer = cogl_pixel_array_new_with_size (TILE_SIZE,
+                                           TILE_SIZE,
+                                           COGL_PIXEL_FORMAT_RGBA_8888,
+                                           &stride);
 
   g_assert (cogl_is_pixel_array (buffer));
   g_assert (cogl_is_buffer (buffer));
@@ -76,8 +81,12 @@ create_map_tile (TestTile *tile)
   map = cogl_buffer_map (buffer, COGL_BUFFER_ACCESS_WRITE);
   g_assert (map);
 
-  for (i = 0; i < TILE_SIZE * TILE_SIZE * 4; i += 4)
+  line = g_alloca (TILE_SIZE * 4);
-      memcpy (map + i, &tile->color, 4);
+  for (i = 0; i < TILE_SIZE; i += 4)
+    memcpy (line + i, &tile->color, 4);
+
+  for (i = 0; i < TILE_SIZE; i++)
+    memcpy (map + stride, line, 4);
 
   cogl_buffer_unmap (buffer);
 
@@ -95,7 +104,7 @@ create_set_region_tile (TestTile *tile)
   guchar *data;
   guint i;
 
-  buffer = cogl_pixel_array_new_for_size (TILE_SIZE,
+  buffer = cogl_pixel_array_with_size (TILE_SIZE,
                                        TILE_SIZE,
                                        COGL_PIXEL_FORMAT_RGBA_8888,
                                        &rowstride);
@@ -143,7 +152,7 @@ create_set_data_tile (TestTile *tile)
   guchar *data;
   guint i;
 
-  buffer = cogl_pixel_array_new_for_size (TILE_SIZE,
+  buffer = cogl_pixel_array_new_with_size (TILE_SIZE,
                                            TILE_SIZE,
                                            COGL_PIXEL_FORMAT_RGBA_8888,
                                            &rowstride);
@@ -152,17 +161,12 @@ create_set_data_tile (TestTile *tile)
   g_assert (cogl_is_buffer (buffer));
   g_assert_cmpint (cogl_buffer_get_size (buffer), ==, rowstride * TILE_SIZE);
 
-  /* while at it, set/get the hint */
-  cogl_buffer_set_usage_hint (buffer, COGL_BUFFER_USAGE_HINT_TEXTURE);
-  g_assert_cmpint (cogl_buffer_get_usage_hint (buffer),
-                   ==,
-                   COGL_BUFFER_USAGE_HINT_TEXTURE);
-
   /* create a buffer with the data we want to copy to the buffer */
   data = g_malloc (TILE_SIZE * TILE_SIZE * 4);
   for (i = 0; i < TILE_SIZE * TILE_SIZE * 4; i += 4)
       memcpy (data + i, &tile->color, 4);
 
+  /* FIXME: this doesn't consider the rowstride */
   res = cogl_buffer_set_data (buffer, 0, data, TILE_SIZE * TILE_SIZE * 4);
   g_assert (res);