diff options
Diffstat (limited to 'cc/math_util.cc')
| -rw-r--r-- | cc/math_util.cc | 63 |
1 files changed, 8 insertions, 55 deletions
diff --git a/cc/math_util.cc b/cc/math_util.cc index 9312d10..2e0349c 100644 --- a/cc/math_util.cc +++ b/cc/math_util.cc @@ -107,7 +107,7 @@ gfx::Rect MathUtil::mapClippedRect(const gfx::Transform& transform, const gfx::R gfx::RectF MathUtil::mapClippedRect(const gfx::Transform& transform, const gfx::RectF& srcRect) { - if (MathUtil::isIdentityOrTranslation(transform)) + if (transform.IsIdentityOrTranslation()) return srcRect + gfx::Vector2dF(static_cast<float>(transform.matrix().getDouble(0, 3)), static_cast<float>(transform.matrix().getDouble(1, 3))); // Apply the transform, but retain the result in homogeneous coordinates. @@ -122,7 +122,7 @@ gfx::RectF MathUtil::mapClippedRect(const gfx::Transform& transform, const gfx:: gfx::RectF MathUtil::projectClippedRect(const gfx::Transform& transform, const gfx::RectF& srcRect) { - if (MathUtil::isIdentityOrTranslation(transform)) + if (transform.IsIdentityOrTranslation()) return srcRect + gfx::Vector2dF(static_cast<float>(transform.matrix().getDouble(0, 3)), static_cast<float>(transform.matrix().getDouble(1, 3))); // Perform the projection, but retain the result in homogeneous coordinates. @@ -241,7 +241,7 @@ gfx::RectF MathUtil::computeEnclosingClippedRect(const HomogeneousCoordinate& h1 gfx::QuadF MathUtil::mapQuad(const gfx::Transform& transform, const gfx::QuadF& q, bool& clipped) { - if (MathUtil::isIdentityOrTranslation(transform)) { + if (transform.IsIdentityOrTranslation()) { gfx::QuadF mappedQuad(q); mappedQuad += gfx::Vector2dF(static_cast<float>(transform.matrix().getDouble(0, 3)), static_cast<float>(transform.matrix().getDouble(1, 3))); clipped = false; @@ -373,7 +373,7 @@ static inline float scaleOnAxis(double a, double b, double c) gfx::Vector2dF MathUtil::computeTransform2dScaleComponents(const gfx::Transform& transform) { - if (hasPerspective(transform)) + if (transform.HasPerspective()) return gfx::Vector2dF(1, 1); float xScale = scaleOnAxis(transform.matrix().getDouble(0, 0), transform.matrix().getDouble(1, 0), transform.matrix().getDouble(2, 0)); float yScale = scaleOnAxis(transform.matrix().getDouble(0, 1), transform.matrix().getDouble(1, 1), transform.matrix().getDouble(2, 1)); @@ -394,69 +394,22 @@ gfx::Vector2dF MathUtil::projectVector(gfx::Vector2dF source, gfx::Vector2dF des return gfx::Vector2dF(projectedLength * destination.x(), projectedLength * destination.y()); } -bool MathUtil::isBackFaceVisible(const gfx::Transform& transform) -{ - // Compute whether a layer with a forward-facing normal of (0, 0, 1) would - // have its back face visible after applying the transform. - // - // This is done by transforming the normal and seeing if the resulting z - // value is positive or negative. However, note that transforming a normal - // actually requires using the inverse-transpose of the original transform. - - // TODO (shawnsingh) make this perform more efficiently - we do not - // actually need to instantiate/invert/transpose any matrices, exploiting the - // fact that we only need to transform (0, 0, 1, 0). - gfx::Transform inverseTransform = MathUtil::inverse(transform); - const SkMatrix44& mInv = inverseTransform.matrix(); - - return mInv.getDouble(2, 2) < 0; -} - -bool MathUtil::isIdentityOrTranslation(const gfx::Transform& transform) -{ - const SkMatrix44& matrix = transform.matrix(); - - bool hasNoPerspective = !matrix.getDouble(3, 0) && !matrix.getDouble(3, 1) && !matrix.getDouble(3, 2) && (matrix.getDouble(3, 3) == 1); - bool hasNoRotationOrSkew = !matrix.getDouble(0, 1) && !matrix.getDouble(0, 2) && !matrix.getDouble(1, 0) && - !matrix.getDouble(1, 2) && !matrix.getDouble(2, 0) && !matrix.getDouble(2, 1); - bool hasNoScale = matrix.getDouble(0, 0) == 1 && matrix.getDouble(1, 1) == 1 && matrix.getDouble(2, 2) == 1; - - return hasNoPerspective && hasNoRotationOrSkew && hasNoScale; -} - -bool MathUtil::hasPerspective(const gfx::Transform& transform) -{ - // Mathematically it is a bit too strict to expect the 4th element to be - // equal to 1. However, the only non-perspective case where this element - // becomes non-1 is when it was explicitly initialized. In that case it - // still causes us to have a nontrivial divide-by-w, so we count it as - // being perspective here. - const SkMatrix44& matrix = transform.matrix(); - return matrix.getDouble(3, 0) || matrix.getDouble(3, 1) || matrix.getDouble(3, 2) || (matrix.getDouble(3, 3) != 1); -} - void MathUtil::rotateEulerAngles(gfx::Transform* transform, double eulerX, double eulerY, double eulerZ) { // TODO (shawnsingh): make this implementation faster and more accurate by - // hard-coding each matrix instead of calling rotateAxisAngle(). + // hard-coding each matrix instead of calling RotateAbout(). gfx::Transform rotationAboutX; gfx::Transform rotationAboutY; gfx::Transform rotationAboutZ; - MathUtil::rotateAxisAngle(&rotationAboutX, 1, 0, 0, eulerX); - MathUtil::rotateAxisAngle(&rotationAboutY, 0, 1, 0, eulerY); - MathUtil::rotateAxisAngle(&rotationAboutZ, 0, 0, 1, eulerZ); + rotationAboutX.RotateAboutXAxis(eulerX); + rotationAboutY.RotateAboutYAxis(eulerY); + rotationAboutZ.RotateAboutZAxis(eulerZ); gfx::Transform composite = rotationAboutZ * rotationAboutY * rotationAboutX; transform->PreconcatTransform(composite); } -void MathUtil::rotateAxisAngle(gfx::Transform* transform, double i, double j, double k, double degrees) -{ - gfx::Vector3dF axis(i, j, k); - transform->RotateAbout(axis, degrees); -} - gfx::Transform MathUtil::inverse(const gfx::Transform& transform) { gfx::Transform result; |