chromium/ui/gfx/geometry/transform.h

// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/354829279): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif

#ifndef UI_GFX_GEOMETRY_TRANSFORM_H_
#define UI_GFX_GEOMETRY_TRANSFORM_H_

#include <iosfwd>
#include <memory>
#include <optional>
#include <string>

#include "ui/gfx/geometry/axis_transform2d.h"
#include "ui/gfx/geometry/geometry_skia_export.h"
#include "ui/gfx/geometry/matrix44.h"

namespace gfx {

class BoxF;
class Rect;
class RectF;
class Point;
class PointF;
class Point3F;
class QuadF;
class Quaternion;
class Vector2dF;
class Vector3dF;
struct DecomposedTransform;

// 4x4 Transformation matrix. Depending on the complexity of the matrix, it may
// be internally stored as an AxisTransform2d (float precision) or a full
// Matrix44 (4x4 double precision). Which one is used only affects precision and
// performance.
// - On construction (including constructors and static functions returning a
//   new Transform object), AxisTransform2d will be used if it the matrix will
//   be 2d scale and/or translation, otherwise Matrix44, with some exceptions
//   (e.g. ColMajor()) described in the method comments.
// - On mutation, if the matrix has been using AxisTransform2d and the result
//   can still be 2d scale and/or translation, AxisTransform2d will still be
//   used, otherwise Matrix44, with some exceptions (e.g. set_rc()) described
//   in the method comments.
// - On assignment, the new matrix will keep the choice of the rhs matrix.
//
class GEOMETRY_SKIA_EXPORT Transform { … };

// This is declared here for use in gtest-based unit tests but is defined in
// the //ui/gfx:test_support target. Depend on that to use this in your unit
// test. This should not be used in production code - call ToString() instead.
void PrintTo(const Transform& transform, ::std::ostream* os);

}  // namespace gfx

#endif  // UI_GFX_GEOMETRY_TRANSFORM_H_