1 files changed, 120 insertions, 0 deletions
diff --git a/gfx/angle/checkout/src/libANGLE/TransformFeedback.h b/gfx/angle/checkout/src/libANGLE/TransformFeedback.h
new file mode 100644
index 0000000000..e55d0054c1
--- /dev/null
+++ b/gfx/angle/checkout/src/libANGLE/TransformFeedback.h
@@ -0,0 +1,120 @@
+//
+// Copyright 2014 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+#ifndef LIBANGLE_TRANSFORM_FEEDBACK_H_
+#define LIBANGLE_TRANSFORM_FEEDBACK_H_
+
+#include "libANGLE/RefCountObject.h"
+
+#include "common/PackedEnums.h"
+#include "common/angleutils.h"
+#include "libANGLE/Debug.h"
+
+#include "angle_gl.h"
+
+namespace rx
+{
+class GLImplFactory;
+class TransformFeedbackImpl;
+class TransformFeedbackGL;
+}  // namespace rx
+
+namespace gl
+{
+class Buffer;
+struct Caps;
+class Context;
+class Program;
+
+class TransformFeedbackState final : angle::NonCopyable
+{
+  public:
+    TransformFeedbackState(size_t maxIndexedBuffers);
+    ~TransformFeedbackState();
+
+    const OffsetBindingPointer<Buffer> &getIndexedBuffer(size_t idx) const;
+    const std::vector<OffsetBindingPointer<Buffer>> &getIndexedBuffers() const;
+    const Program *getBoundProgram() const { return mProgram; }
+    GLsizeiptr getVerticesDrawn() const { return mVerticesDrawn; }
+    GLsizeiptr getPrimitivesDrawn() const;
+
+  private:
+    friend class TransformFeedback;
+
+    std::string mLabel;
+
+    bool mActive;
+    PrimitiveMode mPrimitiveMode;
+    bool mPaused;
+    GLsizeiptr mVerticesDrawn;
+    GLsizeiptr mVertexCapacity;
+
+    Program *mProgram;
+
+    std::vector<OffsetBindingPointer<Buffer>> mIndexedBuffers;
+};
+
+class TransformFeedback final : public RefCountObject<TransformFeedbackID>, public LabeledObject
+{
+  public:
+    TransformFeedback(rx::GLImplFactory *implFactory, TransformFeedbackID id, const Caps &caps);
+    ~TransformFeedback() override;
+    void onDestroy(const Context *context) override;
+
+    angle::Result setLabel(const Context *context, const std::string &label) override;
+    const std::string &getLabel() const override;
+
+    angle::Result begin(const Context *context, PrimitiveMode primitiveMode, Program *program);
+    angle::Result end(const Context *context);
+    angle::Result pause(const Context *context);
+    angle::Result resume(const Context *context);
+
+    bool isActive() const { return mState.mActive; }
+
+    bool isPaused() const;
+    PrimitiveMode getPrimitiveMode() const;
+    // Validates that the vertices produced by a draw call will fit in the bound transform feedback
+    // buffers.
+    bool checkBufferSpaceForDraw(GLsizei count, GLsizei primcount) const;
+    // This must be called after each draw call when transform feedback is enabled to keep track of
+    // how many vertices have been written to the buffers. This information is needed by
+    // checkBufferSpaceForDraw because each draw call appends vertices to the buffers starting just
+    // after the last vertex of the previous draw call.
+    void onVerticesDrawn(const Context *context, GLsizei count, GLsizei primcount);
+
+    bool hasBoundProgram(ShaderProgramID program) const;
+
+    angle::Result bindIndexedBuffer(const Context *context,
+                                    size_t index,
+                                    Buffer *buffer,
+                                    size_t offset,
+                                    size_t size);
+    const OffsetBindingPointer<Buffer> &getIndexedBuffer(size_t index) const;
+    size_t getIndexedBufferCount() const;
+    const std::vector<OffsetBindingPointer<Buffer>> &getIndexedBuffers() const;
+
+    GLsizeiptr getVerticesDrawn() const { return mState.getVerticesDrawn(); }
+    GLsizeiptr getPrimitivesDrawn() const { return mState.getPrimitivesDrawn(); }
+
+    // Returns true if any buffer bound to this object is also bound to another target.
+    bool buffersBoundForOtherUseInWebGL() const;
+
+    angle::Result detachBuffer(const Context *context, BufferID bufferID);
+
+    rx::TransformFeedbackImpl *getImplementation() const;
+
+    void onBindingChanged(const Context *context, bool bound);
+
+  private:
+    void bindProgram(const Context *context, Program *program);
+
+    TransformFeedbackState mState;
+    rx::TransformFeedbackImpl *mImplementation;
+};
+
+}  // namespace gl
+
+#endif  // LIBANGLE_TRANSFORM_FEEDBACK_H_