harfbuzz/src/hb-paint.hh

221 lines
7.5 KiB
C++

/*
* Copyright © 2022 Matthias Clasen
*
* 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_PAINT_HH
#define HB_PAINT_HH
#include "hb.hh"
#include "hb-face.hh"
#include "hb-font.hh"
#define HB_PAINT_FUNCS_IMPLEMENT_CALLBACKS \
HB_PAINT_FUNC_IMPLEMENT (push_transform) \
HB_PAINT_FUNC_IMPLEMENT (pop_transform) \
HB_PAINT_FUNC_IMPLEMENT (push_clip_glyph) \
HB_PAINT_FUNC_IMPLEMENT (push_clip_rectangle) \
HB_PAINT_FUNC_IMPLEMENT (pop_clip) \
HB_PAINT_FUNC_IMPLEMENT (color) \
HB_PAINT_FUNC_IMPLEMENT (image) \
HB_PAINT_FUNC_IMPLEMENT (linear_gradient) \
HB_PAINT_FUNC_IMPLEMENT (radial_gradient) \
HB_PAINT_FUNC_IMPLEMENT (sweep_gradient) \
HB_PAINT_FUNC_IMPLEMENT (push_group) \
HB_PAINT_FUNC_IMPLEMENT (pop_group) \
/* ^--- Add new callbacks here */
struct hb_paint_funcs_t
{
hb_object_header_t header;
struct {
#define HB_PAINT_FUNC_IMPLEMENT(name) hb_paint_##name##_func_t name;
HB_PAINT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_PAINT_FUNC_IMPLEMENT
} func;
struct {
#define HB_PAINT_FUNC_IMPLEMENT(name) void *name;
HB_PAINT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_PAINT_FUNC_IMPLEMENT
} *user_data;
struct {
#define HB_PAINT_FUNC_IMPLEMENT(name) hb_destroy_func_t name;
HB_PAINT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_PAINT_FUNC_IMPLEMENT
} *destroy;
void push_transform (void *paint_data,
float xx, float yx,
float xy, float yy,
float dx, float dy)
{ func.push_transform (this, paint_data,
xx, yx, xy, yy, dx, dy,
!user_data ? nullptr : user_data->push_transform); }
void pop_transform (void *paint_data)
{ func.pop_transform (this, paint_data,
!user_data ? nullptr : user_data->pop_transform); }
void push_clip_glyph (void *paint_data,
hb_codepoint_t glyph,
hb_font_t *font)
{ func.push_clip_glyph (this, paint_data,
glyph,
font,
!user_data ? nullptr : user_data->push_clip_glyph); }
void push_clip_rectangle (void *paint_data,
float xmin, float ymin, float xmax, float ymax)
{ func.push_clip_rectangle (this, paint_data,
xmin, ymin, xmax, ymax,
!user_data ? nullptr : user_data->push_clip_rectangle); }
void pop_clip (void *paint_data)
{ func.pop_clip (this, paint_data,
!user_data ? nullptr : user_data->pop_clip); }
void color (void *paint_data,
hb_bool_t is_foreground,
hb_color_t color)
{ func.color (this, paint_data,
is_foreground, color,
!user_data ? nullptr : user_data->color); }
bool image (void *paint_data,
hb_blob_t *image,
unsigned width, unsigned height,
hb_tag_t format,
float slant,
hb_glyph_extents_t *extents)
{ return func.image (this, paint_data,
image, width, height, format, slant, extents,
!user_data ? nullptr : user_data->image); }
void linear_gradient (void *paint_data,
hb_color_line_t *color_line,
float x0, float y0,
float x1, float y1,
float x2, float y2)
{ func.linear_gradient (this, paint_data,
color_line, x0, y0, x1, y1, x2, y2,
!user_data ? nullptr : user_data->linear_gradient); }
void radial_gradient (void *paint_data,
hb_color_line_t *color_line,
float x0, float y0, float r0,
float x1, float y1, float r1)
{ func.radial_gradient (this, paint_data,
color_line, x0, y0, r0, x1, y1, r1,
!user_data ? nullptr : user_data->radial_gradient); }
void sweep_gradient (void *paint_data,
hb_color_line_t *color_line,
float x0, float y0,
float start_angle,
float end_angle)
{ func.sweep_gradient (this, paint_data,
color_line, x0, y0, start_angle, end_angle,
!user_data ? nullptr : user_data->sweep_gradient); }
void push_group (void *paint_data)
{ func.push_group (this, paint_data,
!user_data ? nullptr : user_data->push_group); }
void pop_group (void *paint_data,
hb_paint_composite_mode_t mode)
{ func.pop_group (this, paint_data,
mode,
!user_data ? nullptr : user_data->pop_group); }
/* Internal specializations. */
void push_root_transform (void *paint_data,
const hb_font_t *font)
{
float upem = font->face->get_upem ();
int xscale = font->x_scale, yscale = font->y_scale;
float slant = font->slant_xy;
push_transform (paint_data,
xscale/upem, 0, slant * yscale/upem, yscale/upem, 0, 0);
}
void push_inverse_root_transform (void *paint_data,
hb_font_t *font)
{
float upem = font->face->get_upem ();
int xscale = font->x_scale ? font->x_scale : upem;
int yscale = font->y_scale ? font->y_scale : upem;
float slant = font->slant_xy;
push_transform (paint_data,
upem/xscale, 0, -slant * upem/xscale, upem/yscale, 0, 0);
}
HB_NODISCARD
bool push_translate (void *paint_data,
float dx, float dy)
{
if (!dx && !dy)
return false;
push_transform (paint_data,
1.f, 0.f, 0.f, 1.f, dx, dy);
return true;
}
HB_NODISCARD
bool push_scale (void *paint_data,
float sx, float sy)
{
if (sx == 1.f && sy == 1.f)
return false;
push_transform (paint_data,
sx, 0.f, 0.f, sy, 0.f, 0.f);
return true;
}
HB_NODISCARD
bool push_rotate (void *paint_data,
float a)
{
if (!a)
return false;
float cc = cosf (a * (float) M_PI);
float ss = sinf (a * (float) M_PI);
push_transform (paint_data, cc, ss, -ss, cc, 0.f, 0.f);
return true;
}
HB_NODISCARD
bool push_skew (void *paint_data,
float sx, float sy)
{
if (!sx && !sy)
return false;
float x = +tanf (sx * (float) M_PI);
float y = -tanf (sy * (float) M_PI);
push_transform (paint_data, 1.f, y, x, 1.f, 0.f, 0.f);
return true;
}
};
DECLARE_NULL_INSTANCE (hb_paint_funcs_t);
#endif /* HB_PAINT_HH */