Move incomplete texture logic to shared helper.
The incomplete texture handling is similar between the D3D and Vulkan
back-ends. We create 1x1 textures, initialize them to black, and bind
them when we detect incomplete textures. We would also bind incomplete
textures when we detect feedback loops. In the GL back-end, we
wouldn't detect feedback loops, and would allow the driver to handle
incompleteness.
Instead implement this in a shared helper class, and do the feedback
loop detection in the front-end for every back-end. This makes our
behaviour more consistent between back-ends, and prevents undefined
behaviour.
Because initializing multisample textures is tricky (they
can't be updated with TexImage calls) we do a bit of a workaround so
the back-end can clear the incomplete multisample texture initially.
This progresses the initial Vulkan textures implementation.
BUG=angleproject:2167
Change-Id: I79ddcc0711fcc986f2578a52ac6f701231d241ac
Reviewed-on: https://chromium-review.googlesource.com/700993
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
diff --git a/src/libANGLE/renderer/renderer_utils.h b/src/libANGLE/renderer/renderer_utils.h
index 37ca1de..d4aabf3 100644
--- a/src/libANGLE/renderer/renderer_utils.h
+++ b/src/libANGLE/renderer/renderer_utils.h
@@ -217,6 +217,37 @@
bool unpackPremultiplyAlpha,
bool unpackUnmultiplyAlpha);
+// Incomplete textures are 1x1 textures filled with black, used when samplers are incomplete.
+// This helper class encapsulates handling incomplete textures. Because the GL back-end
+// can take advantage of the driver's incomplete textures, and because clearing multisample
+// textures is so difficult, we can keep an instance of this class in the back-end instead
+// of moving the logic to the Context front-end.
+
+// This interface allows us to call-back to init a multisample texture.
+class MultisampleTextureInitializer
+{
+ public:
+ virtual gl::Error initializeMultisampleTextureToBlack(const gl::Context *context,
+ gl::Texture *glTexture) = 0;
+};
+
+class IncompleteTextureSet final : angle::NonCopyable
+{
+ public:
+ IncompleteTextureSet();
+ ~IncompleteTextureSet();
+
+ void onDestroy(const gl::Context *context);
+
+ gl::Error getIncompleteTexture(const gl::Context *context,
+ GLenum type,
+ MultisampleTextureInitializer *multisampleInitializer,
+ gl::Texture **textureOut);
+
+ private:
+ gl::TextureMap mIncompleteTextures;
+};
+
} // namespace rx
#endif // LIBANGLE_RENDERER_RENDERER_UTILS_H_