1 files changed, 71 insertions, 0 deletions
diff --git a/gfx/layers/opengl/GLBlitTextureImageHelper.h b/gfx/layers/opengl/GLBlitTextureImageHelper.h
new file mode 100644
index 000000000..91cb1bf85
--- /dev/null
+++ b/gfx/layers/opengl/GLBlitTextureImageHelper.h
@@ -0,0 +1,71 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim: set ts=8 sts=4 et sw=4 tw=80: */
+/* 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 GLBLITTEXTUREIMAGEHELPER_H_
+#define GLBLITTEXTUREIMAGEHELPER_H_
+
+#include "mozilla/Attributes.h"
+#include "GLContextTypes.h"
+#include "GLConsts.h"
+#include "mozilla/gfx/Rect.h"
+
+namespace mozilla {
+namespace gl {
+    class GLContext;
+    class TextureImage;
+} // namespace gl
+namespace layers {
+
+class CompositorOGL;
+
+class GLBlitTextureImageHelper final
+{
+    // The GLContext is the sole owner of the GLBlitTextureImageHelper.
+    CompositorOGL* mCompositor;
+
+    // lazy-initialized things
+    GLuint mBlitProgram, mBlitFramebuffer;
+    void UseBlitProgram();
+    void SetBlitFramebufferForDestTexture(GLuint aTexture);
+
+public:
+
+    explicit GLBlitTextureImageHelper(CompositorOGL *gl);
+    ~GLBlitTextureImageHelper();
+
+    /**
+     * Copy a rectangle from one TextureImage into another.  The
+     * source and destination are given in integer coordinates, and
+     * will be converted to texture coordinates.
+     *
+     * For the source texture, the wrap modes DO apply -- it's valid
+     * to use REPEAT or PAD and expect appropriate behaviour if the source
+     * rectangle extends beyond its bounds.
+     *
+     * For the destination texture, the wrap modes DO NOT apply -- the
+     * destination will be clipped by the bounds of the texture.
+     *
+     * Note: calling this function will cause the following OpenGL state
+     * to be changed:
+     *
+     *   - current program
+     *   - framebuffer binding
+     *   - viewport
+     *   - blend state (will be enabled at end)
+     *   - scissor state (will be enabled at end)
+     *   - vertex attrib 0 and 1 (pointer and enable state [enable state will be disabled at exit])
+     *   - array buffer binding (will be 0)
+     *   - active texture (will be 0)
+     *   - texture 0 binding
+     */
+    void BlitTextureImage(gl::TextureImage *aSrc, const gfx::IntRect& aSrcRect,
+                          gl::TextureImage *aDst, const gfx::IntRect& aDstRect);
+};
+
+} // namespace layers
+} // namespace mozilla
+
+#endif // GLBLITTEXTUREIMAGEHELPER_H_