text: /*
   * Copyright (C) 2009 Apple Inc. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include "third_party/blink/renderer/platform/transforms/matrix_3d_transform_operation.h"
  
  #include "third_party/blink/renderer/platform/transforms/rotation.h"
  #include "ui/gfx/geometry/quaternion.h"
  
  #include <algorithm>
  
  namespace blink {
  
  scoped_refptr<TransformOperation> Matrix3DTransformOperation::Accumulate(
      const TransformOperation& other_op) {
    DCHECK(other_op.IsSameType(*this));
    const auto& other = To<Matrix3DTransformOperation>(other_op);
  
    // If either matrix is non-invertible, fail and fallback to replace.
    if (!matrix_.IsInvertible() || !other.matrix_.IsInvertible())
      return nullptr;
  
    // Similar to interpolation, accumulating 3D matrices is done by decomposing
    // them, accumulating the individual functions, and then recomposing.
  
    TransformationMatrix::DecomposedType from_decomp;
    TransformationMatrix::DecomposedType to_decomp;
    if (!matrix_.Decompose(from_decomp) || !other.matrix_.Decompose(to_decomp))
      return nullptr;
  
    // Scale is accumulated using 1-based addition.
    from_decomp.scale_x += to_decomp.scale_x - 1;
    from_decomp.scale_y += to_decomp.scale_y - 1;
    from_decomp.scale_z += to_decomp.scale_z - 1;
  
    // Skew can be added.
    from_decomp.skew_xy += to_decomp.skew_xy;
    from_decomp.skew_xz += to_decomp.skew_xz;
    from_decomp.skew_yz += to_decomp.skew_yz;
  
    // To accumulate quaternions, we multiply them. This is equivalent to 'adding'
    // the rotations that they represent.
    gfx::Quaternion from_quaternion(
        from_decomp.quaternion_x, from_decomp.quaternion_y,
        from_decomp.quaternion_z, from_decomp.quaternion_w);
    gfx::Quaternion to_quaternion(to_decomp.quaternion_x, to_decomp.quaternion_y,
                                  to_decomp.quaternion_z, to_decomp.quaternion_w);
  
    gfx::Quaternion result_quaternion = from_quaternion * to_quaternion;
    from_decomp.quaternion_x = result_quaternion.x();
    from_decomp.quaternion_y = result_quaternion.y();
    from_decomp.quaternion_z = result_quaternion.z();
    from_decomp.quaternion_w = result_quaternion.w();
  
    // Translate is a simple addition.
    from_decomp.translate_x += to_decomp.translate_x;
    from_decomp.translate_y += to_decomp.translate_y;
    from_decomp.translate_z += to_decomp.translate_z;
  
    // We sum the perspective components; note that w is 1-based.
    from_decomp.perspective_x += to_decomp.perspective_x;
    from_decomp.perspective_y += to_decomp.perspective_y;
    from_decomp.perspective_z += to_decomp.perspective_z;
    from_decomp.perspective_w += to_decomp.perspective_w - 1;
  
    TransformationMatrix result;
    result.Recompose(from_decomp);
    return Matrix3DTransformOperation::Create(result);
  }
  
  scoped_refptr<TransformOperation> Matrix3DTransformOperation::Blend(
      const TransformOperation* from,
      double progress,
      bool blend_to_identity) {
    if (from && !from->IsSameType(*this))
      return this;
  
    // Convert the TransformOperations into matrices. Fail the blend operation
    // if either of the matrices is non-invertible.
    FloatSize size;
    TransformationMatrix from_t;
    TransformationMatrix to_t;
    if (from) {
      from->Apply(from_t, size);
      if (!from_t.IsInvertible())
        return nullptr;
    }
  
    Apply(to_t, size);
    if (!to_t.IsInvertible())
      return nullptr;
  
    if (blend_to_identity)
      std::swap(from_t, to_t);
  
    to_t.Blend(from_t, progress);
    return Matrix3DTransformOperation::Create(to_t);
  }
  
  scoped_refptr<TransformOperation> Matrix3DTransformOperation::Zoom(
      double factor) {
    TransformationMatrix result = matrix_;
    result.Zoom(factor);
    return Create(result);
  }
  
  }  // namespace blink
  