diff options
Diffstat (limited to 'gfx/harfbuzz/src/OT/glyf/path-builder.hh')
| -rw-r--r-- | gfx/harfbuzz/src/OT/glyf/path-builder.hh | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/OT/glyf/path-builder.hh b/gfx/harfbuzz/src/OT/glyf/path-builder.hh new file mode 100644 index 0000000000..f7f732d336 --- /dev/null +++ b/gfx/harfbuzz/src/OT/glyf/path-builder.hh @@ -0,0 +1,189 @@ +#ifndef OT_GLYF_PATH_BUILDER_HH +#define OT_GLYF_PATH_BUILDER_HH + + +#include "../../hb.hh" + + +namespace OT { +namespace glyf_impl { + + +struct path_builder_t +{ + hb_font_t *font; + hb_draw_session_t *draw_session; + + struct optional_point_t + { + optional_point_t () {} + optional_point_t (float x_, float y_) : has_data (true), x (x_), y (y_) {} + operator bool () const { return has_data; } + + bool has_data = false; + float x = 0.; + float y = 0.; + + optional_point_t lerp (optional_point_t p, float t) + { return optional_point_t (x + t * (p.x - x), y + t * (p.y - y)); } + } first_oncurve, first_offcurve, first_offcurve2, last_offcurve, last_offcurve2; + + path_builder_t (hb_font_t *font_, hb_draw_session_t &draw_session_) : + font (font_), draw_session (&draw_session_) {} + + /* based on https://github.com/RazrFalcon/ttf-parser/blob/4f32821/src/glyf.rs#L287 + See also: + * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM01/Chap1.html + * https://stackoverflow.com/a/20772557 + * + * Cubic support added. */ + void consume_point (const contour_point_t &point) + { + bool is_on_curve = point.flag & glyf_impl::SimpleGlyph::FLAG_ON_CURVE; +#ifdef HB_NO_CUBIC_GLYF + bool is_cubic = false; +#else + bool is_cubic = !is_on_curve && (point.flag & glyf_impl::SimpleGlyph::FLAG_CUBIC); +#endif + optional_point_t p (font->em_fscalef_x (point.x), font->em_fscalef_y (point.y)); + if (!first_oncurve) + { + if (is_on_curve) + { + first_oncurve = p; + draw_session->move_to (p.x, p.y); + } + else + { + if (is_cubic && !first_offcurve2) + { + first_offcurve2 = first_offcurve; + first_offcurve = p; + } + else if (first_offcurve) + { + optional_point_t mid = first_offcurve.lerp (p, .5f); + first_oncurve = mid; + last_offcurve = p; + draw_session->move_to (mid.x, mid.y); + } + else + first_offcurve = p; + } + } + else + { + if (last_offcurve) + { + if (is_on_curve) + { + if (last_offcurve2) + { + draw_session->cubic_to (last_offcurve2.x, last_offcurve2.y, + last_offcurve.x, last_offcurve.y, + p.x, p.y); + last_offcurve2 = optional_point_t (); + } + else + draw_session->quadratic_to (last_offcurve.x, last_offcurve.y, + p.x, p.y); + last_offcurve = optional_point_t (); + } + else + { + if (is_cubic && !last_offcurve2) + { + last_offcurve2 = last_offcurve; + last_offcurve = p; + } + else + { + optional_point_t mid = last_offcurve.lerp (p, .5f); + + if (is_cubic) + { + draw_session->cubic_to (last_offcurve2.x, last_offcurve2.y, + last_offcurve.x, last_offcurve.y, + mid.x, mid.y); + last_offcurve2 = optional_point_t (); + } + else + draw_session->quadratic_to (last_offcurve.x, last_offcurve.y, + mid.x, mid.y); + last_offcurve = p; + } + } + } + else + { + if (is_on_curve) + draw_session->line_to (p.x, p.y); + else + last_offcurve = p; + } + } + + if (point.is_end_point) + { + if (first_offcurve && last_offcurve) + { + optional_point_t mid = last_offcurve.lerp (first_offcurve2 ? + first_offcurve2 : + first_offcurve, .5f); + if (last_offcurve2) + draw_session->cubic_to (last_offcurve2.x, last_offcurve2.y, + last_offcurve.x, last_offcurve.y, + mid.x, mid.y); + else + draw_session->quadratic_to (last_offcurve.x, last_offcurve.y, + mid.x, mid.y); + last_offcurve = optional_point_t (); + } + /* now check the rest */ + + if (first_offcurve && first_oncurve) + { + if (first_offcurve2) + draw_session->cubic_to (first_offcurve2.x, first_offcurve2.y, + first_offcurve.x, first_offcurve.y, + first_oncurve.x, first_oncurve.y); + else + draw_session->quadratic_to (first_offcurve.x, first_offcurve.y, + first_oncurve.x, first_oncurve.y); + } + else if (last_offcurve && first_oncurve) + { + if (last_offcurve2) + draw_session->cubic_to (last_offcurve2.x, last_offcurve2.y, + last_offcurve.x, last_offcurve.y, + first_oncurve.x, first_oncurve.y); + else + draw_session->quadratic_to (last_offcurve.x, last_offcurve.y, + first_oncurve.x, first_oncurve.y); + } + else if (first_oncurve) + draw_session->line_to (first_oncurve.x, first_oncurve.y); + else if (first_offcurve) + { + float x = first_offcurve.x, y = first_offcurve.y; + draw_session->move_to (x, y); + draw_session->quadratic_to (x, y, x, y); + } + + /* Getting ready for the next contour */ + first_oncurve = first_offcurve = last_offcurve = last_offcurve2 = optional_point_t (); + draw_session->close_path (); + } + } + void points_end () {} + + bool is_consuming_contour_points () { return true; } + contour_point_t *get_phantoms_sink () { return nullptr; } +}; + + +} /* namespace glyf_impl */ +} /* namespace OT */ + + +#endif /* OT_GLYF_PATH_BUILDER_HH */ |