commit 24930b382a45ac020f018c9f1f76c76b074e6466
author Jiawei Shao <jiawei.shao@intel.com> Mon Mar 25 00:54:58 2019 +0000
committer Commit Bot service account <commit-bot@chromium.org> Mon Mar 25 00:54:58 2019 +0000
tree 9aed4f3fe1cb708efeff5f5618a4732dccf199b6
parent 07950e80fe36028ed9cca0a4a99a8b08e9bb4fdf

Workaround GL error when creating texture view from external GL textures

This patch adds a workaround on the GL error when we use glTextureView()
on a GL texture which is created outside DAWN and not configured by
glTexStorage*d(). glTextureView() is only allowed to be used on the
textures configured by glTexStorage*D(). When the external GL texture
is configured by glTexImage2D() (for example, textures from GLFW),
calling glTextureView() will cause an INVALID_OPERATION error.

To workaround this issue, we refer the solution on the Metal backend
that we avoid calling glTextureView() on the following senarios:
1. We may call glTextureView() only when the usage of the texture
   includes Sampled or Storage.
2. We won't call glTextureView() if the view uses the same format as the
   original texture, the whole mipmap levels and array slices.

BUG=dawn:16

Change-Id: Ibdfaa122ac061a2e2bb47f76e0030f1d0fc548a2
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/5780
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>

src/dawn_native/opengl/TextureGL.cpp

diff --git a/src/dawn_native/opengl/TextureGL.cpp b/src/dawn_native/opengl/TextureGL.cpp
index bf9bac6..8f70cf3 100644
--- a/src/dawn_native/opengl/TextureGL.cpp
+++ b/src/dawn_native/opengl/TextureGL.cpp
@@ -83,6 +83,37 @@
             return handle;
         }
 
+        bool UsageNeedsTextureView(dawn::TextureUsageBit usage) {
+            constexpr dawn::TextureUsageBit kUsageNeedingTextureView =
+                dawn::TextureUsageBit::Storage | dawn::TextureUsageBit::Sampled;
+            return usage & kUsageNeedingTextureView;
+        }
+
+        bool RequiresCreatingNewTextureView(const TextureBase* texture,
+                                            const TextureViewDescriptor* textureViewDescriptor) {
+            if (texture->GetFormat() != textureViewDescriptor->format) {
+                return true;
+            }
+
+            if (texture->GetArrayLayers() != textureViewDescriptor->arrayLayerCount) {
+                return true;
+            }
+
+            if (texture->GetNumMipLevels() != textureViewDescriptor->mipLevelCount) {
+                return true;
+            }
+
+            switch (textureViewDescriptor->dimension) {
+                case dawn::TextureViewDimension::Cube:
+                case dawn::TextureViewDimension::CubeArray:
+                    return true;
+                default:
+                    break;
+            }
+
+            return false;
+        }
+
     }  // namespace
 
     // Texture
@@ -144,24 +175,35 @@
     // TextureView
 
     TextureView::TextureView(TextureBase* texture, const TextureViewDescriptor* descriptor)
-        : TextureViewBase(texture, descriptor) {
+        : TextureViewBase(texture, descriptor), mOwnsHandle(false) {
         mTarget = TargetForTextureViewDimension(descriptor->dimension);
 
-        // glTextureView() is supported on OpenGL version >= 4.3
-        // TODO(jiawei.shao@intel.com): support texture view on OpenGL version <= 4.2
-        mHandle = GenTexture();
-        const Texture* textureGL = ToBackend(texture);
-        TextureFormatInfo textureViewFormat = GetGLFormatInfo(descriptor->format);
-        glTextureView(mHandle, mTarget, textureGL->GetHandle(), textureViewFormat.internalFormat,
-                      descriptor->baseMipLevel, descriptor->mipLevelCount,
-                      descriptor->baseArrayLayer, descriptor->arrayLayerCount);
+        if (!UsageNeedsTextureView(texture->GetUsage())) {
+            mHandle = 0;
+        } else if (!RequiresCreatingNewTextureView(texture, descriptor)) {
+            mHandle = ToBackend(texture)->GetHandle();
+        } else {
+            // glTextureView() is supported on OpenGL version >= 4.3
+            // TODO(jiawei.shao@intel.com): support texture view on OpenGL version <= 4.2
+            mHandle = GenTexture();
+            const Texture* textureGL = ToBackend(texture);
+            TextureFormatInfo textureViewFormat = GetGLFormatInfo(descriptor->format);
+            glTextureView(mHandle, mTarget, textureGL->GetHandle(),
+                          textureViewFormat.internalFormat, descriptor->baseMipLevel,
+                          descriptor->mipLevelCount, descriptor->baseArrayLayer,
+                          descriptor->arrayLayerCount);
+            mOwnsHandle = true;
+        }
     }
 
     TextureView::~TextureView() {
-        glDeleteTextures(1, &mHandle);
+        if (mOwnsHandle) {
+            glDeleteTextures(1, &mHandle);
+        }
     }
 
     GLuint TextureView::GetHandle() const {
+        ASSERT(mHandle != 0);
         return mHandle;
     }
 

src/dawn_native/opengl/TextureGL.h

diff --git a/src/dawn_native/opengl/TextureGL.h b/src/dawn_native/opengl/TextureGL.h
index 5b12da5..05d5c9e 100644
--- a/src/dawn_native/opengl/TextureGL.h
+++ b/src/dawn_native/opengl/TextureGL.h
@@ -55,6 +55,7 @@
       private:
         GLuint mHandle;
         GLenum mTarget;
+        bool mOwnsHandle;
     };
 
 }}  // namespace dawn_native::opengl