Disallow glBlitFramebuffer for multi-view framebuffers

src/libANGLE/Framebuffer.cpp

@@ -1564,6 +1564,16 @@ GLint Framebuffer::getDefaultSamples() const
     return mState.getDefaultSamples();
 }
 
+GLenum Framebuffer::getMultiviewLayout() const
+{
+    const FramebufferAttachment *firstAttachment = getFirstNonNullAttachment();
+    if (firstAttachment == nullptr)
+    {
+        return GL_NONE;
+    }
+    return firstAttachment->getMultiviewLayout();
+}
+
 GLboolean Framebuffer::getDefaultFixedSampleLocations() const
 {
     return mState.getDefaultFixedSampleLocations();

src/libANGLE/Framebuffer.h

@@ -291,6 +291,7 @@ class Framebuffer final : public LabeledObject, public OnAttachmentDirtyReceiver
     bool formsCopyingFeedbackLoopWith(GLuint copyTextureID,
                                       GLint copyTextureLevel,
                                       GLint copyTextureLayer) const;
+    GLenum getMultiviewLayout() const;
 
   private:
     void detachResourceById(const Context *context, GLenum resourceType, GLuint resourceId);

src/libANGLE/validationES.cpp

@@ -1809,6 +1809,22 @@ bool ValidateBlitFramebufferParameters(ValidationContext *context,
         }
     }
 
+    // ANGLE_multiview, Revision 1:
+    // Calling BlitFramebuffer will result in an INVALID_FRAMEBUFFER_OPERATION error if the
+    // multi-view layout of the current draw framebuffer or read framebuffer is not NONE.
+    if (readFramebuffer->getMultiviewLayout() != GL_NONE)
+    {
+        context->handleError(InvalidFramebufferOperation()
+                             << "Attempt to read from a multi-view framebuffer.");
+        return false;
+    }
+    if (drawFramebuffer->getMultiviewLayout() != GL_NONE)
+    {
+        context->handleError(InvalidFramebufferOperation()
+                             << "Attempt to write to a multi-view framebuffer.");
+        return false;
+    }
+
     return true;
 }
 

src/tests/gl_tests/FramebufferMultiviewTest.cpp

@@ -423,4 +423,39 @@ TEST_P(FramebufferMultiviewTest, InvalidCopyTex)
     }
 }
 
+// Test that glBlitFramebuffer generates an invalid framebuffer operation when either the current
+// draw framebuffer, or current read framebuffer have multiview attachments.
+TEST_P(FramebufferMultiviewTest, InvalidBlit)
+{
+    if (!requestMultiviewExtension())
+    {
+        return;
+    }
+
+    mTexture2D = CreateTexture2D(GL_RGBA8, GL_RGBA, GL_UNSIGNED_BYTE);
+    ASSERT_GL_NO_ERROR();
+
+    const GLint viewportOffsets[2] = {0};
+    glFramebufferTextureMultiviewSideBySideANGLE(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, mTexture2D,
+                                                 0, 1, &viewportOffsets[0]);
+    ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
+    ASSERT_GL_NO_ERROR();
+
+    // Blit with the active read framebuffer having multiview attachments.
+    {
+        glBindFramebuffer(GL_READ_FRAMEBUFFER, mFramebuffer);
+        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
+        glBlitFramebuffer(0, 0, 1, 1, 0, 0, 1, 1, GL_COLOR_BUFFER_BIT, GL_NEAREST);
+        EXPECT_GL_ERROR(GL_INVALID_FRAMEBUFFER_OPERATION);
+    }
+
+    // Blit with the active draw framebuffer having multiview attachments.
+    {
+        glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
+        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, mFramebuffer);
+        glBlitFramebuffer(0, 0, 1, 1, 0, 0, 1, 1, GL_COLOR_BUFFER_BIT, GL_NEAREST);
+        EXPECT_GL_ERROR(GL_INVALID_FRAMEBUFFER_OPERATION);
+    }
+}
+
 ANGLE_INSTANTIATE_TEST(FramebufferMultiviewTest, ES3_OPENGL());
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