1 files changed, 368 insertions, 0 deletions
diff --git a/gfx/gl/ScopedGLHelpers.h b/gfx/gl/ScopedGLHelpers.h
new file mode 100644
index 000000000..f0a91c69a
--- /dev/null
+++ b/gfx/gl/ScopedGLHelpers.h
@@ -0,0 +1,368 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef SCOPEDGLHELPERS_H_
+#define SCOPEDGLHELPERS_H_
+
+#include "GLDefs.h"
+#include "mozilla/UniquePtr.h"
+
+namespace mozilla {
+namespace gl {
+
+class GLContext;
+
+#ifdef DEBUG
+bool IsContextCurrent(GLContext* gl);
+#endif
+
+//RAII via CRTP!
+template <class Derived>
+struct ScopedGLWrapper
+{
+private:
+    bool mIsUnwrapped;
+
+protected:
+    GLContext* const mGL;
+
+    explicit ScopedGLWrapper(GLContext* gl)
+        : mIsUnwrapped(false)
+        , mGL(gl)
+    {
+        MOZ_ASSERT(&ScopedGLWrapper<Derived>::Unwrap == &Derived::Unwrap);
+        MOZ_ASSERT(&Derived::UnwrapImpl);
+        MOZ_ASSERT(IsContextCurrent(mGL));
+    }
+
+    virtual ~ScopedGLWrapper() {
+        if (!mIsUnwrapped)
+            Unwrap();
+    }
+
+public:
+    void Unwrap() {
+        MOZ_ASSERT(!mIsUnwrapped);
+        MOZ_ASSERT(IsContextCurrent(mGL));
+
+        Derived* derived = static_cast<Derived*>(this);
+        derived->UnwrapImpl();
+
+        mIsUnwrapped = true;
+    }
+};
+
+// Wraps glEnable/Disable.
+struct ScopedGLState
+    : public ScopedGLWrapper<ScopedGLState>
+{
+    friend struct ScopedGLWrapper<ScopedGLState>;
+
+protected:
+    const GLenum mCapability;
+    bool mOldState;
+
+public:
+    // Use |newState = true| to enable, |false| to disable.
+    ScopedGLState(GLContext* aGL, GLenum aCapability, bool aNewState);
+    // variant that doesn't change state; simply records existing state to be
+    // restored by the destructor
+    ScopedGLState(GLContext* aGL, GLenum aCapability);
+
+protected:
+    void UnwrapImpl();
+};
+
+// Saves and restores with GetUserBoundFB and BindUserFB.
+struct ScopedBindFramebuffer
+    : public ScopedGLWrapper<ScopedBindFramebuffer>
+{
+    friend struct ScopedGLWrapper<ScopedBindFramebuffer>;
+
+protected:
+    GLuint mOldReadFB;
+    GLuint mOldDrawFB;
+
+private:
+    void Init();
+
+public:
+    explicit ScopedBindFramebuffer(GLContext* aGL);
+    ScopedBindFramebuffer(GLContext* aGL, GLuint aNewFB);
+
+protected:
+    void UnwrapImpl();
+};
+
+struct ScopedBindTextureUnit
+    : public ScopedGLWrapper<ScopedBindTextureUnit>
+{
+    friend struct ScopedGLWrapper<ScopedBindTextureUnit>;
+
+protected:
+    GLenum mOldTexUnit;
+
+public:
+    ScopedBindTextureUnit(GLContext* aGL, GLenum aTexUnit);
+
+protected:
+    void UnwrapImpl();
+};
+
+
+struct ScopedTexture
+    : public ScopedGLWrapper<ScopedTexture>
+{
+    friend struct ScopedGLWrapper<ScopedTexture>;
+
+protected:
+    GLuint mTexture;
+
+public:
+    explicit ScopedTexture(GLContext* aGL);
+    GLuint Texture() { return mTexture; }
+
+protected:
+    void UnwrapImpl();
+};
+
+
+struct ScopedFramebuffer
+    : public ScopedGLWrapper<ScopedFramebuffer>
+{
+    friend struct ScopedGLWrapper<ScopedFramebuffer>;
+
+protected:
+    GLuint mFB;
+
+public:
+    explicit ScopedFramebuffer(GLContext* aGL);
+    GLuint FB() { return mFB; }
+
+protected:
+    void UnwrapImpl();
+};
+
+
+struct ScopedRenderbuffer
+    : public ScopedGLWrapper<ScopedRenderbuffer>
+{
+    friend struct ScopedGLWrapper<ScopedRenderbuffer>;
+
+protected:
+    GLuint mRB;
+
+public:
+    explicit ScopedRenderbuffer(GLContext* aGL);
+    GLuint RB() { return mRB; }
+
+protected:
+    void UnwrapImpl();
+};
+
+
+struct ScopedBindTexture
+    : public ScopedGLWrapper<ScopedBindTexture>
+{
+    friend struct ScopedGLWrapper<ScopedBindTexture>;
+
+protected:
+    const GLenum mTarget;
+    const GLuint mOldTex;
+
+public:
+    ScopedBindTexture(GLContext* aGL, GLuint aNewTex,
+                      GLenum aTarget = LOCAL_GL_TEXTURE_2D);
+
+protected:
+    void UnwrapImpl();
+};
+
+
+struct ScopedBindRenderbuffer
+    : public ScopedGLWrapper<ScopedBindRenderbuffer>
+{
+    friend struct ScopedGLWrapper<ScopedBindRenderbuffer>;
+
+protected:
+    GLuint mOldRB;
+
+private:
+    void Init();
+
+public:
+    explicit ScopedBindRenderbuffer(GLContext* aGL);
+
+    ScopedBindRenderbuffer(GLContext* aGL, GLuint aNewRB);
+
+protected:
+    void UnwrapImpl();
+};
+
+
+struct ScopedFramebufferForTexture
+    : public ScopedGLWrapper<ScopedFramebufferForTexture>
+{
+    friend struct ScopedGLWrapper<ScopedFramebufferForTexture>;
+
+protected:
+    bool mComplete; // True if the framebuffer we create is complete.
+    GLuint mFB;
+
+public:
+    ScopedFramebufferForTexture(GLContext* aGL, GLuint aTexture,
+                                GLenum aTarget = LOCAL_GL_TEXTURE_2D);
+
+    bool IsComplete() const {
+        return mComplete;
+    }
+
+    GLuint FB() const {
+        MOZ_ASSERT(IsComplete());
+        return mFB;
+    }
+
+protected:
+    void UnwrapImpl();
+};
+
+struct ScopedFramebufferForRenderbuffer
+    : public ScopedGLWrapper<ScopedFramebufferForRenderbuffer>
+{
+    friend struct ScopedGLWrapper<ScopedFramebufferForRenderbuffer>;
+
+protected:
+    bool mComplete; // True if the framebuffer we create is complete.
+    GLuint mFB;
+
+public:
+    ScopedFramebufferForRenderbuffer(GLContext* aGL, GLuint aRB);
+
+    bool IsComplete() const {
+        return mComplete;
+    }
+
+    GLuint FB() const {
+        return mFB;
+    }
+
+protected:
+    void UnwrapImpl();
+};
+
+struct ScopedViewportRect
+    : public ScopedGLWrapper<ScopedViewportRect>
+{
+    friend struct ScopedGLWrapper<ScopedViewportRect>;
+
+protected:
+    GLint mSavedViewportRect[4];
+
+public:
+    ScopedViewportRect(GLContext* aGL, GLint x, GLint y, GLsizei width, GLsizei height);
+
+protected:
+    void UnwrapImpl();
+};
+
+struct ScopedScissorRect
+    : public ScopedGLWrapper<ScopedScissorRect>
+{
+    friend struct ScopedGLWrapper<ScopedScissorRect>;
+
+protected:
+    GLint mSavedScissorRect[4];
+
+public:
+    ScopedScissorRect(GLContext* aGL, GLint x, GLint y, GLsizei width, GLsizei height);
+    explicit ScopedScissorRect(GLContext* aGL);
+
+protected:
+    void UnwrapImpl();
+};
+
+struct ScopedVertexAttribPointer
+    : public ScopedGLWrapper<ScopedVertexAttribPointer>
+{
+    friend struct ScopedGLWrapper<ScopedVertexAttribPointer>;
+
+protected:
+    GLuint mAttribIndex;
+    GLint mAttribEnabled;
+    GLint mAttribSize;
+    GLint mAttribStride;
+    GLint mAttribType;
+    GLint mAttribNormalized;
+    GLint mAttribBufferBinding;
+    void* mAttribPointer;
+    GLuint mBoundBuffer;
+
+public:
+    ScopedVertexAttribPointer(GLContext* aGL, GLuint index, GLint size, GLenum type, realGLboolean normalized,
+                              GLsizei stride, GLuint buffer, const GLvoid* pointer);
+    explicit ScopedVertexAttribPointer(GLContext* aGL, GLuint index);
+
+protected:
+    void WrapImpl(GLuint index);
+    void UnwrapImpl();
+};
+
+struct ScopedGLDrawState
+{
+    explicit ScopedGLDrawState(GLContext* gl);
+    ~ScopedGLDrawState();
+
+    GLuint boundProgram;
+    GLuint boundBuffer;
+
+    ScopedGLState blend;
+    ScopedGLState cullFace;
+    ScopedGLState depthTest;
+    ScopedGLState dither;
+    ScopedGLState polyOffsFill;
+    ScopedGLState sampleAToC;
+    ScopedGLState sampleCover;
+    ScopedGLState scissor;
+    ScopedGLState stencil;
+
+    GLuint maxAttrib;
+    UniquePtr<GLint[]> attrib_enabled;
+    GLint attrib0_size;
+    GLint attrib0_stride;
+    GLint attrib0_type;
+    GLint attrib0_normalized;
+    GLint attrib0_bufferBinding;
+    void* attrib0_pointer;
+
+    realGLboolean colorMask[4];
+    GLint viewport[4];
+    GLint scissorBox[4];
+    GLContext* const mGL;
+};
+
+struct ScopedPackState
+    : public ScopedGLWrapper<ScopedPackState>
+{
+    friend struct ScopedGLWrapper<ScopedPackState>;
+
+protected:
+    GLint mAlignment;
+
+    GLuint mPixelBuffer;
+    GLint mRowLength;
+    GLint mSkipPixels;
+    GLint mSkipRows;
+
+public:
+    explicit ScopedPackState(GLContext* gl);
+
+protected:
+    void UnwrapImpl();
+};
+
+} /* namespace gl */
+} /* namespace mozilla */
+
+#endif /* SCOPEDGLHELPERS_H_ */