Source code
Revision control
Copy as Markdown
Other Tools
/*
* Copyright © 2020 Ebrahim Byagowi
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*/
#ifndef HB_DRAW_HH
#define HB_DRAW_HH
#include "hb.hh"
/*
* hb_draw_funcs_t
*/
#define HB_DRAW_FUNCS_IMPLEMENT_CALLBACKS \
HB_DRAW_FUNC_IMPLEMENT (move_to) \
HB_DRAW_FUNC_IMPLEMENT (line_to) \
HB_DRAW_FUNC_IMPLEMENT (quadratic_to) \
HB_DRAW_FUNC_IMPLEMENT (cubic_to) \
HB_DRAW_FUNC_IMPLEMENT (close_path) \
/* ^--- Add new callbacks here */
struct hb_draw_funcs_t
{
hb_object_header_t header;
struct {
#define HB_DRAW_FUNC_IMPLEMENT(name) hb_draw_##name##_func_t name;
HB_DRAW_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_DRAW_FUNC_IMPLEMENT
} func;
struct {
#define HB_DRAW_FUNC_IMPLEMENT(name) void *name;
HB_DRAW_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_DRAW_FUNC_IMPLEMENT
} *user_data;
struct {
#define HB_DRAW_FUNC_IMPLEMENT(name) hb_destroy_func_t name;
HB_DRAW_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_DRAW_FUNC_IMPLEMENT
} *destroy;
void emit_move_to (void *draw_data, hb_draw_state_t &st,
float to_x, float to_y)
{ func.move_to (this, draw_data, &st,
to_x, to_y,
!user_data ? nullptr : user_data->move_to); }
void emit_line_to (void *draw_data, hb_draw_state_t &st,
float to_x, float to_y)
{ func.line_to (this, draw_data, &st,
to_x, to_y,
!user_data ? nullptr : user_data->line_to); }
void emit_quadratic_to (void *draw_data, hb_draw_state_t &st,
float control_x, float control_y,
float to_x, float to_y)
{ func.quadratic_to (this, draw_data, &st,
control_x, control_y,
to_x, to_y,
!user_data ? nullptr : user_data->quadratic_to); }
void emit_cubic_to (void *draw_data, hb_draw_state_t &st,
float control1_x, float control1_y,
float control2_x, float control2_y,
float to_x, float to_y)
{ func.cubic_to (this, draw_data, &st,
control1_x, control1_y,
control2_x, control2_y,
to_x, to_y,
!user_data ? nullptr : user_data->cubic_to); }
void emit_close_path (void *draw_data, hb_draw_state_t &st)
{ func.close_path (this, draw_data, &st,
!user_data ? nullptr : user_data->close_path); }
void
HB_ALWAYS_INLINE
move_to (void *draw_data, hb_draw_state_t &st,
float to_x, float to_y)
{
if (unlikely (st.path_open)) close_path (draw_data, st);
st.current_x = to_x;
st.current_y = to_y;
}
void
HB_ALWAYS_INLINE
line_to (void *draw_data, hb_draw_state_t &st,
float to_x, float to_y)
{
if (unlikely (!st.path_open)) start_path (draw_data, st);
emit_line_to (draw_data, st, to_x, to_y);
st.current_x = to_x;
st.current_y = to_y;
}
void
HB_ALWAYS_INLINE
quadratic_to (void *draw_data, hb_draw_state_t &st,
float control_x, float control_y,
float to_x, float to_y)
{
if (unlikely (!st.path_open)) start_path (draw_data, st);
emit_quadratic_to (draw_data, st, control_x, control_y, to_x, to_y);
st.current_x = to_x;
st.current_y = to_y;
}
void
HB_ALWAYS_INLINE
cubic_to (void *draw_data, hb_draw_state_t &st,
float control1_x, float control1_y,
float control2_x, float control2_y,
float to_x, float to_y)
{
if (unlikely (!st.path_open)) start_path (draw_data, st);
emit_cubic_to (draw_data, st, control1_x, control1_y, control2_x, control2_y, to_x, to_y);
st.current_x = to_x;
st.current_y = to_y;
}
void
HB_ALWAYS_INLINE
close_path (void *draw_data, hb_draw_state_t &st)
{
if (likely (st.path_open))
{
if ((st.path_start_x != st.current_x) || (st.path_start_y != st.current_y))
emit_line_to (draw_data, st, st.path_start_x, st.path_start_y);
emit_close_path (draw_data, st);
}
st.path_open = false;
st.path_start_x = st.current_x = st.path_start_y = st.current_y = 0;
}
protected:
void start_path (void *draw_data, hb_draw_state_t &st)
{
assert (!st.path_open);
emit_move_to (draw_data, st, st.current_x, st.current_y);
st.path_open = true;
st.path_start_x = st.current_x;
st.path_start_y = st.current_y;
}
};
DECLARE_NULL_INSTANCE (hb_draw_funcs_t);
struct hb_draw_session_t
{
hb_draw_session_t (hb_draw_funcs_t *funcs_, void *draw_data_, float slant_ = 0.f)
: slant {slant_}, not_slanted {slant == 0.f},
funcs {funcs_}, draw_data {draw_data_}, st HB_DRAW_STATE_DEFAULT
{}
~hb_draw_session_t () { close_path (); }
HB_ALWAYS_INLINE
void move_to (float to_x, float to_y)
{
if (likely (not_slanted))
funcs->move_to (draw_data, st,
to_x, to_y);
else
funcs->move_to (draw_data, st,
to_x + to_y * slant, to_y);
}
HB_ALWAYS_INLINE
void line_to (float to_x, float to_y)
{
if (likely (not_slanted))
funcs->line_to (draw_data, st,
to_x, to_y);
else
funcs->line_to (draw_data, st,
to_x + to_y * slant, to_y);
}
void
HB_ALWAYS_INLINE
quadratic_to (float control_x, float control_y,
float to_x, float to_y)
{
if (likely (not_slanted))
funcs->quadratic_to (draw_data, st,
control_x, control_y,
to_x, to_y);
else
funcs->quadratic_to (draw_data, st,
control_x + control_y * slant, control_y,
to_x + to_y * slant, to_y);
}
void
HB_ALWAYS_INLINE
cubic_to (float control1_x, float control1_y,
float control2_x, float control2_y,
float to_x, float to_y)
{
if (likely (not_slanted))
funcs->cubic_to (draw_data, st,
control1_x, control1_y,
control2_x, control2_y,
to_x, to_y);
else
funcs->cubic_to (draw_data, st,
control1_x + control1_y * slant, control1_y,
control2_x + control2_y * slant, control2_y,
to_x + to_y * slant, to_y);
}
HB_ALWAYS_INLINE
void close_path ()
{
funcs->close_path (draw_data, st);
}
public:
float slant;
bool not_slanted;
hb_draw_funcs_t *funcs;
void *draw_data;
hb_draw_state_t st;
};
#endif /* HB_DRAW_HH */