#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;
float y;
optional_point_t mid (optional_point_t p)
{ return optional_point_t ((x + p.x) * 0.5f, (y + p.y) * 0.5f); }
} 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. */
HB_ALWAYS_INLINE
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
constexpr 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 (unlikely (!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.mid (p);
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.mid (p);
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;
}
}
}
void contour_end ()
{
if (first_offcurve && last_offcurve)
{
optional_point_t mid = last_offcurve.mid (first_offcurve2 ?
first_offcurve2 :
first_offcurve);
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 */
