TransformFeedback.h

Enable keyboard shortcuts

//

// 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_