diff options
Diffstat (limited to 'src/2geom/transforms.cpp')
| -rw-r--r-- | src/2geom/transforms.cpp | 26 |
1 files changed, 18 insertions, 8 deletions
diff --git a/src/2geom/transforms.cpp b/src/2geom/transforms.cpp index 091079d5a..41d395297 100644 --- a/src/2geom/transforms.cpp +++ b/src/2geom/transforms.cpp @@ -139,6 +139,24 @@ Affine &Affine::operator*=(Zoom const &z) { return *this; } +Affine Rotate::around(Point const &p, Coord angle) +{ + Affine result = Translate(-p) * Rotate(angle) * Translate(p); + return result; +} + +Affine reflection(Point const & vector, Point const & origin) +{ + Geom::Point vn = unit_vector(vector); + Coord cx2 = vn[X] * vn[X]; + Coord cy2 = vn[Y] * vn[Y]; + Coord c2xy = 2 * vn[X] * vn[Y]; + Affine mirror ( cx2 - cy2, c2xy, + c2xy, cy2 - cx2, + 0, 0 ); + return Translate(-origin) * mirror * Translate(origin); +} + // this checks whether the requirements of TransformConcept are satisfied for all transforms. // if you add a new transform type, include it here! void check_transforms() @@ -173,14 +191,6 @@ void check_transforms() m = z * t; m = z * s; m = z * r; m = z * h; m = z * v; m = z * z; } -Affine reflection(Point const & vector, Point const & origin) { - Geom::Point vec_norm = unit_vector(vector); - Affine mirror ( vec_norm[X]*vec_norm[X] - vec_norm[Y]*vec_norm[Y], 2 * vec_norm[X] * vec_norm[Y] , - 2 * vec_norm[X] * vec_norm[Y], vec_norm[Y]*vec_norm[Y] - vec_norm[X]*vec_norm[X] , - 0 ,0 ); - return Translate(-origin) * mirror * Translate(origin); -} - } // namespace Geom /* |