/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 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 mozilla_gfx_layers_LayersHelpers_h

#define mozilla_gfx_layers_LayersHelpers_h

#include "mozilla/Maybe.h"

#include "mozilla/gfx/Rect.h"

#include "mozilla/gfx/Matrix.h"

#include "mozilla/gfx/Polygon.h"

#include "nsRegion.h"

#include "nsTArray.h"

namespace mozilla {

namespace layers {

class Layer;

// Compute compositor information for copying the backdrop for a mix-blend

// operation.

gfx::IntRect

ComputeBackdropCopyRect(const gfx::Rect& aRect,

                        const gfx::IntRect& aClipRect,

                        const gfx::Matrix4x4& aTransform,

                        const gfx::IntRect& aRenderTargetRect,

                        gfx::Matrix4x4* aOutTransform,

                        gfx::Rect* aOutLayerQuad = nullptr);

// Compute uv-coordinates for a rect inside a texture.

template <typename T>

static inline gfx::Rect

TextureRectToCoords(const T& aRect, const gfx::IntSize& aSize)

{

  return gfx::Rect(

    float(aRect.X()) / aSize.width,

    float(aRect.Y()) / aSize.height,

    float(aRect.Width()) / aSize.width,

    float(aRect.Height()) / aSize.height);

}

// This is defined in Compositor.cpp.

nsTArray<gfx::TexturedTriangle>

GenerateTexturedTriangles(const gfx::Polygon& aPolygon,

                          const gfx::Rect& aRect,

                          const gfx::Rect& aTexRect);

// This is defined in ContainerLayerComposite.cpp.

void TransformLayerGeometry(Layer* aLayer, Maybe<gfx::Polygon>& aGeometry);

} // namespace layers

} // namespace mozilla

#endif // mozilla_gfx_layers_LayersHelpers_h