1 files changed, 133 insertions, 0 deletions
diff --git a/gfx/angle/checkout/src/libANGLE/ImageIndex.h b/gfx/angle/checkout/src/libANGLE/ImageIndex.h
new file mode 100644
index 0000000000..4625d310d8
--- /dev/null
+++ b/gfx/angle/checkout/src/libANGLE/ImageIndex.h
@@ -0,0 +1,133 @@
+//
+// 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.
+//
+
+// ImageIndex.h: A helper struct for indexing into an Image array
+
+#ifndef LIBANGLE_IMAGE_INDEX_H_
+#define LIBANGLE_IMAGE_INDEX_H_
+
+#include "common/PackedEnums.h"
+#include "common/mathutil.h"
+
+#include "angle_gl.h"
+
+namespace gl
+{
+
+class ImageIndexIterator;
+
+class ImageIndex
+{
+  public:
+    ImageIndex();
+    ImageIndex(const ImageIndex &other);
+    ImageIndex &operator=(const ImageIndex &other);
+
+    TextureType getType() const { return mType; }
+    GLint getLevelIndex() const { return mLevelIndex; }
+    GLint getLayerIndex() const { return mLayerIndex; }
+    GLint getLayerCount() const { return mLayerCount; }
+
+    bool hasLayer() const;
+    bool has3DLayer() const;
+    bool usesTex3D() const;
+    GLint cubeMapFaceIndex() const;
+    bool valid() const;
+    // Note that you cannot use this function when the ImageIndex represents an entire level of cube
+    // map.
+    TextureTarget getTarget() const;
+
+    TextureTarget getTargetOrFirstCubeFace() const;
+
+    bool isLayered() const;
+    bool isEntireLevelCubeMap() const;
+
+    static ImageIndex MakeBuffer();
+    static ImageIndex Make2D(GLint levelIndex);
+    static ImageIndex MakeRectangle(GLint levelIndex);
+    static ImageIndex MakeCubeMapFace(TextureTarget target, GLint levelIndex);
+    static ImageIndex Make2DArray(GLint levelIndex, GLint layerIndex = kEntireLevel);
+    static ImageIndex Make2DArrayRange(GLint levelIndex, GLint layerIndex, GLint layerCount);
+    static ImageIndex Make3D(GLint levelIndex, GLint layerIndex = kEntireLevel);
+    static ImageIndex MakeFromTarget(TextureTarget target, GLint levelIndex, GLint depth = 0);
+    static ImageIndex MakeFromType(TextureType type,
+                                   GLint levelIndex,
+                                   GLint layerIndex = kEntireLevel,
+                                   GLint layerCount = 1);
+    static ImageIndex Make2DMultisample();
+    static ImageIndex Make2DMultisampleArray(GLint layerIndex = kEntireLevel);
+    static ImageIndex Make2DMultisampleArrayRange(GLint layerIndex, GLint layerCount);
+
+    static constexpr GLint kEntireLevel = static_cast<GLint>(-1);
+
+    bool operator<(const ImageIndex &b) const;
+    bool operator==(const ImageIndex &b) const;
+    bool operator!=(const ImageIndex &b) const;
+
+    // Only valid for 3D/Cube textures with layers.
+    ImageIndexIterator getLayerIterator(GLint layerCount) const;
+
+  private:
+    friend class ImageIndexIterator;
+
+    ImageIndex(TextureType type, GLint leveIndex, GLint layerIndex, GLint layerCount);
+
+    TextureType mType;
+    GLint mLevelIndex;
+    GLint mLayerIndex;
+    GLint mLayerCount;
+};
+
+// To be used like this:
+//
+// ImageIndexIterator it = ...;
+// while (it.hasNext())
+// {
+//     ImageIndex current = it.next();
+// }
+class ImageIndexIterator
+{
+  public:
+    ImageIndexIterator(const ImageIndexIterator &other);
+
+    static ImageIndexIterator MakeBuffer();
+    static ImageIndexIterator Make2D(GLint minMip, GLint maxMip);
+    static ImageIndexIterator MakeRectangle(GLint minMip, GLint maxMip);
+    static ImageIndexIterator MakeCube(GLint minMip, GLint maxMip);
+    static ImageIndexIterator Make3D(GLint minMip, GLint maxMip, GLint minLayer, GLint maxLayer);
+    static ImageIndexIterator Make2DArray(GLint minMip, GLint maxMip, const GLsizei *layerCounts);
+    static ImageIndexIterator Make2DMultisample();
+    static ImageIndexIterator Make2DMultisampleArray(const GLsizei *layerCounts);
+    static ImageIndexIterator MakeGeneric(TextureType type,
+                                          GLint minMip,
+                                          GLint maxMip,
+                                          GLint minLayer,
+                                          GLint maxLayer);
+
+    ImageIndex next();
+    ImageIndex current() const;
+    bool hasNext() const;
+
+  private:
+    ImageIndexIterator(TextureType type,
+                       const Range<GLint> &mipRange,
+                       const Range<GLint> &layerRange,
+                       const GLsizei *layerCounts);
+
+    GLint maxLayer() const;
+
+    const Range<GLint> mMipRange;
+    const Range<GLint> mLayerRange;
+    const GLsizei *const mLayerCounts;
+
+    ImageIndex mCurrentIndex;
+};
+
+TextureTarget TextureTypeToTarget(TextureType type, GLint layerIndex);
+
+}  // namespace gl
+
+#endif  // LIBANGLE_IMAGE_INDEX_H_