#include <hb.h>
#include <hb-ot.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <cairo.h>
#include <math.h>
#include <unistd.h>
#include <assert.h>
#ifndef MIN
#define MIN(x,y) ((x) < (y) ? (x) : (y))
#endif
#ifndef MAX
#define MAX(x,y) ((x) > (y) ? (x) : (y))
#endif
#ifndef FALSE
#define FALSE 0
#define TRUE 1
#endif
typedef struct {
int level;
cairo_t *cr;
hb_font_t *font;
hb_font_t *unscaled_font;
hb_color_t *colors;
unsigned int num_colors;
hb_color_t foreground_color;
} paint_data_t;
#define INDENT 2
static void
print (paint_data_t *data,
const char *format,
...)
{
va_list args;
printf ("%*s", 2 * data->level, "");
va_start (args, format);
vprintf (format, args);
va_end (args);
printf ("\n");
}
typedef struct {
float r, g, b, a;
} color_t;
static void
get_color (paint_data_t *data,
unsigned int color_index,
float alpha,
color_t *c)
{
hb_color_t color;
if (color_index == 0xffff)
color = data->foreground_color;
else
color = data->colors[color_index];
c->r = hb_color_get_red (color) / 255.;
c->g = hb_color_get_green (color) / 255.;
c->b = hb_color_get_blue (color) / 255.;
c->a = (hb_color_get_alpha (color) / 255.) * alpha;
}
static cairo_operator_t
to_operator (hb_paint_composite_mode_t mode)
{
switch (mode)
{
case HB_PAINT_COMPOSITE_MODE_CLEAR: return CAIRO_OPERATOR_CLEAR;
case HB_PAINT_COMPOSITE_MODE_SRC: return CAIRO_OPERATOR_SOURCE;
case HB_PAINT_COMPOSITE_MODE_DEST: return CAIRO_OPERATOR_DEST;
case HB_PAINT_COMPOSITE_MODE_SRC_OVER: return CAIRO_OPERATOR_OVER;
case HB_PAINT_COMPOSITE_MODE_DEST_OVER: return CAIRO_OPERATOR_DEST_OVER;
case HB_PAINT_COMPOSITE_MODE_SRC_IN: return CAIRO_OPERATOR_IN;
case HB_PAINT_COMPOSITE_MODE_DEST_IN: return CAIRO_OPERATOR_DEST_IN;
case HB_PAINT_COMPOSITE_MODE_SRC_OUT: return CAIRO_OPERATOR_OUT;
case HB_PAINT_COMPOSITE_MODE_DEST_OUT: return CAIRO_OPERATOR_DEST_OUT;
case HB_PAINT_COMPOSITE_MODE_SRC_ATOP: return CAIRO_OPERATOR_ATOP;
case HB_PAINT_COMPOSITE_MODE_DEST_ATOP: return CAIRO_OPERATOR_DEST_ATOP;
case HB_PAINT_COMPOSITE_MODE_XOR: return CAIRO_OPERATOR_XOR;
case HB_PAINT_COMPOSITE_MODE_PLUS: return CAIRO_OPERATOR_ADD;
case HB_PAINT_COMPOSITE_MODE_SCREEN: return CAIRO_OPERATOR_SCREEN;
case HB_PAINT_COMPOSITE_MODE_OVERLAY: return CAIRO_OPERATOR_OVERLAY;
case HB_PAINT_COMPOSITE_MODE_DARKEN: return CAIRO_OPERATOR_DARKEN;
case HB_PAINT_COMPOSITE_MODE_LIGHTEN: return CAIRO_OPERATOR_LIGHTEN;
case HB_PAINT_COMPOSITE_MODE_COLOR_DODGE: return CAIRO_OPERATOR_COLOR_DODGE;
case HB_PAINT_COMPOSITE_MODE_COLOR_BURN: return CAIRO_OPERATOR_COLOR_BURN;
case HB_PAINT_COMPOSITE_MODE_HARD_LIGHT: return CAIRO_OPERATOR_HARD_LIGHT;
case HB_PAINT_COMPOSITE_MODE_SOFT_LIGHT: return CAIRO_OPERATOR_SOFT_LIGHT;
case HB_PAINT_COMPOSITE_MODE_DIFFERENCE: return CAIRO_OPERATOR_DIFFERENCE;
case HB_PAINT_COMPOSITE_MODE_EXCLUSION: return CAIRO_OPERATOR_EXCLUSION;
case HB_PAINT_COMPOSITE_MODE_MULTIPLY: return CAIRO_OPERATOR_MULTIPLY;
case HB_PAINT_COMPOSITE_MODE_HSL_HUE: return CAIRO_OPERATOR_HSL_HUE;
case HB_PAINT_COMPOSITE_MODE_HSL_SATURATION: return CAIRO_OPERATOR_HSL_SATURATION;
case HB_PAINT_COMPOSITE_MODE_HSL_COLOR: return CAIRO_OPERATOR_HSL_COLOR;
case HB_PAINT_COMPOSITE_MODE_HSL_LUMINOSITY: return CAIRO_OPERATOR_HSL_LUMINOSITY;
default:;
}
return CAIRO_OPERATOR_SOURCE;
}
static cairo_extend_t
cairo_extend (hb_paint_extend_t extend)
{
switch (extend)
{
case HB_PAINT_EXTEND_PAD: return CAIRO_EXTEND_PAD;
case HB_PAINT_EXTEND_REPEAT: return CAIRO_EXTEND_REPEAT;
case HB_PAINT_EXTEND_REFLECT: return CAIRO_EXTEND_REFLECT;
default:;
}
return CAIRO_EXTEND_PAD;
}
static void
push_transform (hb_paint_funcs_t *funcs,
void *paint_data,
float xx, float yx,
float xy, float yy,
float dx, float dy,
void *user_data)
{
paint_data_t *data = user_data;
cairo_matrix_t m;
print (data, "start transform %f %f %f %f %f %f", xx, yx, xy, yy, dx, dy);
cairo_save (data->cr);
cairo_matrix_init (&m, xx, yx, xy, yy, dx, dy);
cairo_transform (data->cr, &m);
data->level++;
}
static void
pop_transform (hb_paint_funcs_t *funcs,
void *paint_data,
void *user_data)
{
paint_data_t *data = user_data;
data->level--;
cairo_restore (data->cr);
print (data, "end transform");
}
static void
move_to (hb_draw_funcs_t *funcs, void *draw_data,
hb_draw_state_t *st,
float x, float y,
void *user_data)
{
paint_data_t *data = user_data;
print (data, "move to %f %f", x, y);
cairo_move_to (data->cr, x, y);
}
static void
line_to (hb_draw_funcs_t *funcs, void *draw_data,
hb_draw_state_t *st,
float x, float y,
void *user_data)
{
paint_data_t *data = user_data;
print (data, "line to %f %f", x, y);
cairo_line_to (data->cr, x, y);
}
static void
cubic_to (hb_draw_funcs_t *funcs, void *draw_data,
hb_draw_state_t *st,
float c1x, float c1y,
float c2x, float c2y,
float x, float y,
void *user_data)
{
paint_data_t *data = user_data;
print (data, "curve to %f %f %f %f %f %f", c1x, c1y, c2x, c2y, x, y);
cairo_curve_to (data->cr, c1x, c1y, c2x, c2y, x, y);
}
static void
close_path (hb_draw_funcs_t *funcs, void *draw_data,
hb_draw_state_t *st,
void *user_data)
{
paint_data_t *data = user_data;
print (data, "close path\n");
cairo_close_path (data->cr);
}
static void
push_clip_glyph (hb_paint_funcs_t *funcs,
void *paint_data,
hb_codepoint_t glyph,
void *user_data)
{
paint_data_t *data = user_data;
hb_draw_funcs_t *dfuncs;
print (data, "start clip glyph %u", glyph);
data->level++;
cairo_save (data->cr);
dfuncs = hb_draw_funcs_create ();
hb_draw_funcs_set_move_to_func (dfuncs, move_to, data, NULL);
hb_draw_funcs_set_line_to_func (dfuncs, line_to, data, NULL);
hb_draw_funcs_set_cubic_to_func (dfuncs, cubic_to, data, NULL);
hb_draw_funcs_set_close_path_func (dfuncs, close_path, data, NULL);
cairo_new_path (data->cr);
/* Note: we need to use a upem-scaled, unslanted copy of the font here,
* since hb has already applied the root transform.
*/
hb_font_get_glyph_shape (data->unscaled_font, glyph, dfuncs, data);
cairo_close_path (data->cr);
cairo_clip (data->cr);
hb_draw_funcs_destroy (dfuncs);
}
static void
push_clip_rect (hb_paint_funcs_t *funcs,
void *paint_data,
float xmin, float ymin, float xmax, float ymax,
void *user_data)
{
paint_data_t *data = user_data;
print (data, "start clip rect %f %f %f %f", xmin, ymin, xmax, ymax);
data->level++;
cairo_save (data->cr);
cairo_rectangle (data->cr, xmin, ymin, xmax - xmin, ymax - ymin);
cairo_clip (data->cr);
}
static void
pop_clip (hb_paint_funcs_t *funcs,
void *paint_data,
void *user_data)
{
paint_data_t *data = user_data;
cairo_restore (data->cr);
data->level--;
print (data, "end clip");
}
static void
paint_color (hb_paint_funcs_t *funcs,
void *paint_data,
unsigned int color_index,
float alpha,
void *user_data)
{
paint_data_t *data = user_data;
color_t c;
print (data, "solid %u %f", color_index, alpha);
get_color (data, color_index, alpha, &c);
data->level++;
print (data, "color %f %f %f %f", c.r, c.g, c.b, c.a);
data->level--;
cairo_set_source_rgba (data->cr, c.r, c.g, c.b, c.a);
cairo_paint (data->cr);
}
typedef struct
{
hb_blob_t *blob;
unsigned int offset;
} read_blob_data_t;
cairo_status_t
read_blob (void *closure,
unsigned char *data,
unsigned int length)
{
read_blob_data_t *r = closure;
const char *d;
unsigned int size;
d = hb_blob_get_data (r->blob, &size);
if (r->offset + length > size)
return CAIRO_STATUS_READ_ERROR;
memcpy (data, d + r->offset, length);
r->offset += length;
return CAIRO_STATUS_SUCCESS;
}
static void
paint_image (hb_paint_funcs_t *funcs,
void *paint_data,
hb_codepoint_t glyph,
void *user_data)
{
paint_data_t *data = user_data;
read_blob_data_t r;
cairo_surface_t *surface;
cairo_pattern_t *pattern;
cairo_matrix_t m;
hb_glyph_extents_t extents;
hb_font_get_glyph_extents (data->font, glyph, &extents);
r.blob = hb_ot_color_glyph_reference_png (data->font, glyph);
r.offset = 0;
surface = cairo_image_surface_create_from_png_stream (read_blob, &r);
hb_blob_destroy (r.blob);
pattern = cairo_pattern_create_for_surface (surface);
cairo_matrix_init_scale (&m, 1, -1);
cairo_matrix_translate (&m, extents.x_bearing, - extents.y_bearing);
cairo_pattern_set_matrix (pattern, &m);
cairo_set_source (data->cr, pattern);
cairo_paint (data->cr);
cairo_pattern_destroy (pattern);
cairo_surface_destroy (surface);
}
static void
reduce_anchors (float x0, float y0,
float x1, float y1,
float x2, float y2,
float *xx0, float *yy0,
float *xx1, float *yy1)
{
float q1x, q1y, q2x, q2y;
float s;
float k;
q2x = x2 - x0;
q2y = y2 - y0;
q1x = y1 - x0;
q1y = y1 - y0;
s = q2x * q2x + q2y * q2y;
if (s < 0.000001)
{
*xx0 = x0; *yy0 = y0;
*xx1 = x1; *yy1 = y1;
return;
}
k = (q2x * q1x + q2y * q1y) / s;
*xx0 = x0;
*yy0 = y0;
*xx1 = x1 - k * q2x;
*yy1 = y1 - k * q2y;
}
static int
cmp_color_stop (const void *p1,
const void *p2)
{
const hb_color_stop_t *c1 = p1;
const hb_color_stop_t *c2 = p2;
if (c1->offset < c2->offset)
return -1;
else if (c1->offset > c2->offset)
return 1;
else
return 0;
}
static void
normalize_color_line (hb_color_stop_t *stops,
unsigned int len,
float *omin,
float *omax)
{
float min, max;
qsort (stops, len, sizeof (hb_color_stop_t), cmp_color_stop);
min = max = stops[0].offset;
for (unsigned int i = 0; i < len; i++)
{
min = MIN (min, stops[i].offset);
max = MAX (max, stops[i].offset);
}
if (min != max)
{
for (unsigned int i = 0; i < len; i++)
stops[i].offset = (stops[i].offset - min) / (max - min);
}
*omin = min;
*omax = max;
}
static void
paint_linear_gradient (hb_paint_funcs_t *funcs,
void *paint_data,
hb_color_line_t *color_line,
float x0, float y0,
float x1, float y1,
float x2, float y2,
void *user_data)
{
paint_data_t *data = user_data;
unsigned int len;
hb_color_stop_t *stops;
float xx0, yy0, xx1, yy1;
float xxx0, yyy0, xxx1, yyy1;
float min, max;
cairo_pattern_t *pattern;
len = hb_color_line_get_color_stops (color_line, 0, NULL, NULL);
stops = alloca (len * sizeof (hb_color_stop_t));
hb_color_line_get_color_stops (color_line, 0, &len, stops);
print (data, "linear gradient");
data->level += 1;
print (data, "p0 %f %f", x0, y0);
print (data, "p1 %f %f", x1, y1);
print (data, "p2 %f %f", x2, y2);
print (data, "colors");
data->level += 1;
for (unsigned int i = 0; i < len; i++)
print (data, "%f %u %f", stops[i].offset, stops[i].color_index, stops[i].alpha);
data->level -= 2;
reduce_anchors (x0, y0, x1, y1, x2, y2, &xx0, &yy0, &xx1, &yy1);
normalize_color_line (stops, len, &min, &max);
xxx0 = xx0 + min * (xx1 - xx0);
yyy0 = yy0 + min * (yy1 - yy0);
xxx1 = xx0 + max * (xx1 - xx0);
yyy1 = yy0 + max * (yy1 - yy0);
pattern = cairo_pattern_create_linear (xxx0, yyy0, xxx1, yyy1);
cairo_pattern_set_extend (pattern, cairo_extend (hb_color_line_get_extend (color_line)));
for (unsigned int i = 0; i < len; i++)
{
color_t c;
get_color (data, stops[i].color_index, stops[i].alpha, &c);
cairo_pattern_add_color_stop_rgba (pattern, stops[i].offset, c.r, c.g, c.b, c.a);
}
cairo_set_source (data->cr, pattern);
cairo_paint (data->cr);
cairo_pattern_destroy (pattern);
}
static void
paint_radial_gradient (hb_paint_funcs_t *funcs,
void *paint_data,
hb_color_line_t *color_line,
float x0, float y0, float r0,
float x1, float y1, float r1,
void *user_data)
{
paint_data_t *data = user_data;
unsigned int len;
hb_color_stop_t *stops;
cairo_extend_t extend;
float min, max;
float xx0, yy0, xx1, yy1;
float rr0, rr1;
cairo_pattern_t *pattern;
print (data, "radial gradient");
len = hb_color_line_get_color_stops (color_line, 0, NULL, NULL);
stops = alloca (len * sizeof (hb_color_stop_t));
hb_color_line_get_color_stops (color_line, 0, &len, stops);
extend = cairo_extend (hb_color_line_get_extend (color_line));
normalize_color_line (stops, len, &min, &max);
xx0 = x0 + min * (x1 - x0);
yy0 = y0 + min * (y1 - y0);
xx1 = x0 + max * (x1 - x0);
yy1 = y0 + max * (y1 - y0);
rr0 = r0 + min * (r1 - r0);
rr1 = r0 + max * (r1 - r0);
pattern = cairo_pattern_create_radial (xx0, yy0, rr0, xx1, yy1, rr1);
cairo_pattern_set_extend (pattern, extend);
for (unsigned int i = 0; i < len; i++)
{
color_t c;
get_color (data, stops[i].color_index, stops[i].alpha, &c);
cairo_pattern_add_color_stop_rgba (pattern, stops[i].offset, c.r, c.g, c.b, c.a);
}
cairo_set_source (data->cr, pattern);
cairo_paint (data->cr);
cairo_pattern_destroy (pattern);
}
typedef struct {
float x, y;
} Point;
static inline float
interpolate (float f0, float f1, float f)
{
return f0 + f * (f1 - f0);
}
static inline void
interpolate_points (Point *p0, Point *p1, float f, Point *out)
{
out->x = interpolate (p0->x, p1->x, f);
out->y = interpolate (p0->y, p1->y, f);
}
void
interpolate_colors (color_t *c0, color_t *c1, float k, color_t *c)
{
c->r = c0->r + k * (c1->r - c0->r);
c->g = c0->g + k * (c1->g - c0->g);
c->b = c0->b + k * (c1->b - c0->b);
c->a = c0->a + k * (c1->a - c0->a);
}
static inline float
dot (Point p, Point q)
{
return p.x * q.x + p.y * q.y;
}
static inline Point
normalize (Point p)
{
float len = sqrt (dot (p, p));
return (Point) { p.x / len, p.y / len };
}
static inline Point
sum (Point p, Point q)
{
return (Point) { p.x + q.x, p.y + q.y };
}
static inline Point
difference (Point p, Point q)
{
return (Point) { p.x - q.x, p.y - q.y };
}
static inline Point
scale (Point p, float f)
{
return (Point) { p.x * f, p.y * f };
}
typedef struct {
Point center, p0, c0, c1, p1;
color_t color0, color1;
} Patch;
static void
add_patch (cairo_pattern_t *pattern, Point *center, Patch *p)
{
cairo_mesh_pattern_begin_patch (pattern);
cairo_mesh_pattern_move_to (pattern, center->x, center->y);
cairo_mesh_pattern_line_to (pattern, p->p0.x, p->p0.y);
cairo_mesh_pattern_curve_to (pattern,
p->c0.x, p->c0.y,
p->c1.x, p->c1.y,
p->p1.x, p->p1.y);
cairo_mesh_pattern_line_to (pattern, center->x, center->y);
cairo_mesh_pattern_set_corner_color_rgba (pattern, 0,
p->color0.r,
p->color0.g,
p->color0.b,
p->color0.a);
cairo_mesh_pattern_set_corner_color_rgba (pattern, 1,
p->color0.r,
p->color0.g,
p->color0.b,
p->color0.a);
cairo_mesh_pattern_set_corner_color_rgba (pattern, 2,
p->color1.r,
p->color1.g,
p->color1.b,
p->color1.a);
cairo_mesh_pattern_set_corner_color_rgba (pattern, 3,
p->color1.r,
p->color1.g,
p->color1.b,
p->color1.a);
cairo_mesh_pattern_end_patch (pattern);
}
#define MAX_ANGLE (M_PI / 8.)
static void
add_sweep_gradient_patches1 (float cx, float cy, float radius,
float a0, color_t *c0,
float a1, color_t *c1,
cairo_pattern_t *pattern)
{
Point center = (Point) { cx, cy };
int num_splits;
Point p0;
color_t color0, color1;
num_splits = ceilf (fabs (a1 - a0) / MAX_ANGLE);
p0 = (Point) { cosf (a0), sinf (a0) };
color0 = *c0;
for (int a = 0; a < num_splits; a++)
{
float k = (a + 1.) / num_splits;
float angle1;
Point p1;
Point A, U;
Point C0, C1;
Patch patch;
angle1 = interpolate (a0, a1, k);
interpolate_colors (c0, c1, k, &color1);
patch.color0 = color0;
patch.color1 = color1;
p1 = (Point) { cosf (angle1), sinf (angle1) };
patch.p0 = sum (center, scale (p0, radius));
patch.p1 = sum (center, scale (p1, radius));
A = normalize (sum (p0, p1));
U = (Point) { -A.y, A.x };
C0 = sum (A, scale (U, dot (difference (p0, A), p0) / dot (U, p0)));
C1 = sum (A, scale (U, dot (difference (p1, A), p1) / dot (U, p1)));
patch.c0 = sum (center, scale (sum (C0, scale (difference (C0, p0), 0.33333)), radius));
patch.c1 = sum (center, scale (sum (C1, scale (difference (C1, p1), 0.33333)), radius));
add_patch (pattern, ¢er, &patch);
p0 = p1;
color0 = color1;
}
}
static void
add_sweep_gradient_patches (paint_data_t *data,
hb_color_stop_t *stops,
unsigned int n_stops,
cairo_extend_t extend,
float cx, float cy,
float radius,
float start_angle,
float end_angle,
cairo_pattern_t *pattern)
{
float *angles;
color_t *colors;
color_t color0, color1;
if (start_angle == end_angle)
{
if (extend == CAIRO_EXTEND_PAD)
{
color_t c;
if (start_angle > 0)
{
get_color (data, stops[0].color_index, stops[0].alpha, &c);
add_sweep_gradient_patches1 (cx, cy, radius,
0., &c,
start_angle, &c,
pattern);
}
if (end_angle < 2 * M_PI)
{
get_color (data, stops[n_stops - 1].color_index, stops[n_stops - 1].alpha, &c);
add_sweep_gradient_patches1 (cx, cy, radius,
end_angle, &c,
2 * M_PI, &c,
pattern);
}
}
return;
}
assert (start_angle != end_angle);
/* handle directions */
if (end_angle < start_angle)
{
float angle = end_angle;
end_angle = start_angle;
start_angle = angle;
for (int i = 0; i < n_stops - 1 - i; i++)
{
hb_color_stop_t stop = stops[i];
stops[i] = stops[n_stops - 1 - i];
stops[n_stops - 1 - i] = stop;
}
}
angles = alloca (sizeof (float) * n_stops);
colors = alloca (sizeof (color_t) * n_stops);
for (int i = 0; i < n_stops; i++)
{
angles[i] = start_angle + stops[i].offset * (end_angle - start_angle);
get_color (data, stops[i].color_index, stops[i].alpha, &colors[i]);
}
if (extend == CAIRO_EXTEND_PAD)
{
int pos;
color0 = colors[0];
for (pos = 0; pos < n_stops; pos++)
{
if (angles[pos] >= 0)
{
if (pos > 0)
{
float k = (0 - angles[pos - 1]) / (angles[pos] - angles[pos - 1]);
interpolate_colors (&colors[pos-1], &colors[pos], k, &color0);
}
break;
}
}
if (pos == n_stops)
{
/* everything is below 0 */
color0 = colors[n_stops-1];
add_sweep_gradient_patches1 (cx, cy, radius,
0., &color0,
2 * M_PI, &color0,
pattern);
return;
}
add_sweep_gradient_patches1 (cx, cy, radius,
0., &color0,
angles[pos], &colors[pos],
pattern);
for (pos++; pos < n_stops; pos++)
{
if (angles[pos] <= 2 * M_PI)
{
add_sweep_gradient_patches1 (cx, cy, radius,
angles[pos - 1], &colors[pos-1],
angles[pos], &colors[pos],
pattern);
}
else
{
float k = (2 * M_PI - angles[pos - 1]) / (angles[pos] - angles[pos - 1]);
interpolate_colors (&colors[pos - 1], &colors[pos], k, &color1);
add_sweep_gradient_patches1 (cx, cy, radius,
angles[pos - 1], &colors[pos - 1],
2 * M_PI, &color1,
pattern);
break;
}
}
if (pos == n_stops)
{
/* everything is below 2*M_PI */
color0 = colors[n_stops - 1];
add_sweep_gradient_patches1 (cx, cy, radius,
angles[n_stops - 1], &color0,
2 * M_PI, &color0,
pattern);
return;
}
}
else
{
int k;
float span;
span = angles[n_stops - 1] - angles[0];
k = 0;
if (angles[0] >= 0)
{
float ss = angles[0];
while (ss > 0)
{
if (span > 0)
{
ss -= span;
k--;
}
else
{
ss += span;
k++;
}
}
}
else if (angles[0] < 0)
{
float ee = angles[n_stops - 1];
while (ee < 0)
{
if (span > 0)
{
ee += span;
k++;
}
else
{
ee -= span;
k--;
}
}
}
//assert (angles[0] + k * span <= 0 && 0 < angles[n_stops - 1] + k * span);
for (int l = k; TRUE; l++)
{
for (int i = 1; i < n_stops; i++)
{
float a0, a1;
color_t *c0, *c1;
if ((l % 2 != 0) && (extend == CAIRO_EXTEND_REFLECT))
{
a0 = angles[0] + angles[n_stops - 1] - angles[n_stops - 1 - (i-1)] + l * span;
a1 = angles[0] + angles[n_stops - 1] - angles[n_stops - 1 - i] + l * span;
c0 = &colors[n_stops - 1 - (i - 1)];
c1 = &colors[n_stops - 1 - i];
}
else
{
a0 = angles[i-1] + l * span;
a1 = angles[i] + l * span;
c0 = &colors[i-1];
c1 = &colors[i];
}
if (a1 < 0)
continue;
if (a0 < 0)
{
color_t color;
float f = (0 - a0)/(a1 - a0);
interpolate_colors (c0, c1, f, &color);
add_sweep_gradient_patches1 (cx, cy, radius,
0, &color,
a1, c1,
pattern);
}
else if (a1 >= 2 * M_PI)
{
color_t color;
float f = (2 * M_PI - a0)/(a1 - a0);
interpolate_colors (c0, c1, f, &color);
add_sweep_gradient_patches1 (cx, cy, radius,
a0, c0,
2 * M_PI, &color,
pattern);
goto done;
}
else
{
add_sweep_gradient_patches1 (cx, cy, radius,
a0, c0,
a1, c1,
pattern);
}
}
}
done: ;
}
}
static void
paint_sweep_gradient (hb_paint_funcs_t *funcs,
void *paint_data,
hb_color_line_t *color_line,
float cx, float cy,
float start_angle,
float end_angle,
void *user_data)
{
paint_data_t *data = user_data;
unsigned int len;
hb_color_stop_t *stops;
cairo_extend_t extend;
double x1, y1, x2, y2;
float max_x, max_y, radius;
cairo_pattern_t *pattern;
len = hb_color_line_get_color_stops (color_line, 0, NULL, NULL);
stops = alloca (len * sizeof (hb_color_stop_t));
hb_color_line_get_color_stops (color_line, 0, &len, stops);
qsort (stops, len, sizeof (hb_color_stop_t), cmp_color_stop);
print (data, "sweep gradient");
data->level++;
print (data, "center %f %f", cx, cy);
print (data, "angles %f %f", start_angle, end_angle);
data->level += 1;
for (unsigned int i = 0; i < len; i++)
print (data, "%f %u %f", stops[i].offset, stops[i].color_index, stops[i].alpha);
data->level -= 2;
cairo_clip_extents (data->cr, &x1, &y1, &x2, &y2);
max_x = MAX ((x1 - cx) * (x1 - cx), (x2 - cx) * (x2 - cx));
max_y = MAX ((y1 - cy) * (y1 - cy), (y2 - cy) * (y2 - cy));
radius = sqrt (max_x + max_y);
extend = cairo_extend (hb_color_line_get_extend (color_line));
pattern = cairo_pattern_create_mesh ();
add_sweep_gradient_patches (data, stops, len, extend, cx, cy,
radius, start_angle, end_angle, pattern);
cairo_set_source (data->cr, pattern);
cairo_paint (data->cr);
cairo_pattern_destroy (pattern);
data->level--;
}
static void
push_group (hb_paint_funcs_t *funcs,
void *paint_data,
void *user_data)
{
paint_data_t *data = user_data;
print (data, "push group");
data->level++;
cairo_save (data->cr);
cairo_push_group (data->cr);
}
static void
pop_group (hb_paint_funcs_t *funcs,
void *paint_data,
hb_paint_composite_mode_t mode,
void *user_data)
{
paint_data_t *data = user_data;
cairo_pop_group_to_source (data->cr);
cairo_set_operator (data->cr, to_operator (mode));
cairo_paint (data->cr);
cairo_restore (data->cr);
data->level--;
print (data, "pop group mode %d", mode);
}
int main (int argc, char *argv[])
{
paint_data_t data;
hb_paint_funcs_t *funcs;
hb_blob_t *blob = hb_blob_create_from_file (argv[1]);
hb_face_t *face = hb_face_create (blob, 0);
hb_font_t *font = hb_font_create (face);
hb_font_t *unscaled_font;
hb_font_set_scale (font, 20, 20);
hb_codepoint_t gid = atoi (argv[2]);
hb_glyph_extents_t extents;
cairo_surface_t *surface;
cairo_pattern_t *pattern;
cairo_matrix_t m;
float xmin, ymin, xmax, ymax;
unsigned int upem;
float size = 120.;
hb_font_set_scale (font, size, size);
hb_font_get_glyph_extents (font, gid, &extents);
unscaled_font = hb_font_create (face);
upem = hb_face_get_upem (face);
hb_font_set_scale (unscaled_font, upem, upem);
hb_font_set_synthetic_slant (unscaled_font, 0.);
printf ("size %f upem %u\n", size, upem);
xmin = extents.x_bearing;
xmax = xmin + extents.width;
ymin = - extents.y_bearing;
ymax = - extents.y_bearing - extents.height;
printf ("surface %f %f, offset %f %f\n", ceil (xmax - xmin), ceil (ymax - ymin), - xmin, - ymin);
if ((int) ceil (xmax - xmin) == 0 ||
(int) ceil (ymax - ymin) == 0)
{
printf ("ERROR: empty surface\n");
return 1;
}
surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
(int) ceil (xmax - xmin),
(int) ceil (ymax - ymin));
cairo_surface_set_device_offset (surface, - xmin, ymax);
data.level = 0;
data.cr = cairo_create (surface);
cairo_push_group (data.cr);
data.font = font;
data.unscaled_font = unscaled_font;
data.foreground_color = HB_COLOR (0, 0, 0, 255);
data.num_colors = hb_ot_color_palette_get_colors (hb_font_get_face (font),
0, 0, NULL, NULL);
data.colors = alloca (data.num_colors * sizeof (hb_color_t));
hb_ot_color_palette_get_colors (hb_font_get_face (font),
0, 0, &data.num_colors, data.colors);
funcs = hb_paint_funcs_create ();
hb_paint_funcs_set_push_transform_func (funcs, push_transform, &data, NULL);
hb_paint_funcs_set_pop_transform_func (funcs, pop_transform, &data, NULL);
hb_paint_funcs_set_push_clip_glyph_func (funcs, push_clip_glyph, &data, NULL);
hb_paint_funcs_set_push_clip_rect_func (funcs, push_clip_rect, &data, NULL);
hb_paint_funcs_set_pop_clip_func (funcs, pop_clip, &data, NULL);
hb_paint_funcs_set_push_group_func (funcs, push_group, &data, NULL);
hb_paint_funcs_set_pop_group_func (funcs, pop_group, &data, NULL);
hb_paint_funcs_set_color_func (funcs, paint_color, &data, NULL);
hb_paint_funcs_set_image_func (funcs, paint_image, &data, NULL);
hb_paint_funcs_set_linear_gradient_func (funcs, paint_linear_gradient, &data, NULL);
hb_paint_funcs_set_radial_gradient_func (funcs, paint_radial_gradient, &data, NULL);
hb_paint_funcs_set_sweep_gradient_func (funcs, paint_sweep_gradient, &data, NULL);
hb_font_paint_glyph (font, gid, funcs, NULL);
pattern = cairo_pop_group (data.cr);
cairo_matrix_init_scale (&m, 1, -1);
cairo_matrix_translate (&m, 0, (ymax - ymin) + 2 * ymin);
cairo_pattern_set_matrix (pattern, &m);
cairo_set_source (data.cr, pattern);
cairo_paint (data.cr);
cairo_surface_set_device_offset (surface, - xmin, - ymin);
printf ("writing glyph.png\n");
cairo_surface_write_to_png (surface, "glyph.png");
execvp ("eog", (char *const[]) { "eog", "glyph.png", NULL });
return 0;
}
