From 9139f21e093d9d809ecaa16a0e1d84afea93da32 Mon Sep 17 00:00:00 2001
From: Neil Roberts <neil@linux.intel.com>
Date: Sat, 5 Dec 2009 13:48:03 +0000
Subject: [PATCH] cogl-atlas-texture: Remove textures from the atlas when
mipmapping is required
Mipmaps don't work very well in the current atlas because there is not
enough padding between the textures. If ensure_mipmaps is called it
will now create a new texture and migrate the atlased texture to
it. It will use the same blit mechanism as when migrating so it will
try to use an FBO for a fast blit. However if this is not possible it
will end up downloading the data for the entire atlas which is not
ideal.
---
cogl/cogl-atlas-texture.c | 66 +++++++++++++++++++++++++++++++++------
1 file changed, 57 insertions(+), 9 deletions(-)
diff --git a/cogl/cogl-atlas-texture.c b/cogl/cogl-atlas-texture.c
index 8fb9ae9c8..4d7bf6f9d 100644
--- a/cogl/cogl-atlas-texture.c
+++ b/cogl/cogl-atlas-texture.c
@@ -237,16 +237,17 @@ _cogl_atlas_texture_set_wrap_mode_parameter (CoglTexture *tex,
}
static void
-_cogl_atlas_texture_free (CoglAtlasTexture *atlas_tex)
+_cogl_atlas_texture_remove_from_atlas (CoglAtlasTexture *atlas_tex)
{
- _COGL_GET_CONTEXT (ctx, NO_RETVAL);
-
- /* Remove the texture from the atlas */
if (atlas_tex->in_atlas)
{
- CoglAtlas *atlas = ((atlas_tex->format & COGL_A_BIT) ?
- ctx->atlas_alpha :
- ctx->atlas_no_alpha);
+ CoglAtlas *atlas;
+
+ _COGL_GET_CONTEXT (ctx, NO_RETVAL);
+
+ atlas = ((atlas_tex->format & COGL_A_BIT) ?
+ ctx->atlas_alpha :
+ ctx->atlas_no_alpha);
cogl_atlas_remove_rectangle (atlas, &atlas_tex->rectangle);
@@ -260,7 +261,15 @@ _cogl_atlas_texture_free (CoglAtlasTexture *atlas_tex)
cogl_atlas_get_remaining_space (atlas) * 100 /
(cogl_atlas_get_width (atlas) *
cogl_atlas_get_height (atlas)));
+
+ atlas_tex->in_atlas = FALSE;
}
+}
+
+static void
+_cogl_atlas_texture_free (CoglAtlasTexture *atlas_tex)
+{
+ _cogl_atlas_texture_remove_from_atlas (atlas_tex);
cogl_handle_unref (atlas_tex->sub_texture);
}
@@ -332,8 +341,47 @@ _cogl_atlas_texture_ensure_mipmaps (CoglTexture *tex)
{
CoglAtlasTexture *atlas_tex = COGL_ATLAS_TEXTURE (tex);
- /* FIXME: If mipmaps are required then we need to migrate the
- texture out of the atlas because it will show artifacts */
+ /* Mipmaps do not work well with the current atlas so instead we'll
+ just migrate the texture out and use a regular texture */
+ if (atlas_tex->in_atlas)
+ {
+ CoglHandle atlas_texture;
+ CoglAtlasTextureBlitData blit_data;
+
+ _COGL_GET_CONTEXT (ctx, NO_RETVAL);
+
+ COGL_NOTE (ATLAS, "Migrating texture out of the atlas");
+
+ cogl_handle_unref (atlas_tex->sub_texture);
+
+ if ((atlas_tex->format & COGL_A_BIT))
+ atlas_texture = ctx->atlas_alpha_texture;
+ else
+ atlas_texture = ctx->atlas_no_alpha_texture;
+
+ /* Create a new texture at the right size, not including the
+ border */
+ atlas_tex->sub_texture =
+ cogl_texture_new_with_size (atlas_tex->rectangle.width - 2,
+ atlas_tex->rectangle.height - 2,
+ COGL_TEXTURE_NO_ATLAS,
+ atlas_tex->format);
+
+ /* Blit the data out of the atlas to the new texture. If FBOs
+ aren't available this will end up having to copy the entire
+ atlas texture */
+ _cogl_atlas_texture_blit_begin (&blit_data, atlas_tex->sub_texture,
+ atlas_texture);
+ _cogl_atlas_texture_blit (&blit_data,
+ atlas_tex->rectangle.x + 1,
+ atlas_tex->rectangle.y + 1,
+ 0, 0,
+ atlas_tex->rectangle.width - 2,
+ atlas_tex->rectangle.height - 2);
+ _cogl_atlas_texture_blit_end (&blit_data);
+
+ _cogl_atlas_texture_remove_from_atlas (atlas_tex);
+ }
/* Forward on to the sub texture */
_cogl_texture_ensure_mipmaps (atlas_tex->sub_texture);