diff options
Diffstat (limited to 'experimental/Intersection/CubicSubDivide.cpp')
| -rw-r--r-- | experimental/Intersection/CubicSubDivide.cpp | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/experimental/Intersection/CubicSubDivide.cpp b/experimental/Intersection/CubicSubDivide.cpp index b7cc127f0a..ee7057bbd8 100644 --- a/experimental/Intersection/CubicSubDivide.cpp +++ b/experimental/Intersection/CubicSubDivide.cpp @@ -83,6 +83,22 @@ void sub_divide(const Cubic& src, double t1, double t2, Cubic& dst) { /* cy = */ dst[2].y = (ny * 2 - my) / 18; } +void sub_divide(const Cubic& src, const _Point& a, const _Point& d, + double t1, double t2, _Point dst[2]) { + double ex = interp_cubic_coords(&src[0].x, (t1 * 2 + t2) / 3); + double ey = interp_cubic_coords(&src[0].y, (t1 * 2 + t2) / 3); + double fx = interp_cubic_coords(&src[0].x, (t1 + t2 * 2) / 3); + double fy = interp_cubic_coords(&src[0].y, (t1 + t2 * 2) / 3); + double mx = ex * 27 - a.x * 8 - d.x; + double my = ey * 27 - a.y * 8 - d.y; + double nx = fx * 27 - a.x - d.x * 8; + double ny = fy * 27 - a.y - d.y * 8; + /* bx = */ dst[0].x = (mx * 2 - nx) / 18; + /* by = */ dst[0].y = (my * 2 - ny) / 18; + /* cx = */ dst[1].x = (nx * 2 - mx) / 18; + /* cy = */ dst[1].y = (ny * 2 - my) / 18; +} + /* classic one t subdivision */ static void interp_cubic_coords(const double* src, double* dst, double t) { |