summaryrefslogtreecommitdiff
path: root/examples/cairoshape.c
blob: addde87e8c391b19f3d05188ab4a5ba98761bffc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
/* example to use pangocairo to render arbitrary shapes inside a text layout */

#include <stdio.h>
#include <string.h>

#include <pango/pangocairo.h>

#define BULLET "•"

const char text[] =
"The GNOME project provides two things:\n"
"\n"
"  • The GNOME desktop environment\n"
"  • The GNOME development platform\n"
"  • Planet GNOME";

typedef struct {
  double width, height;
  const char *path;
} MiniSvg;

static MiniSvg GnomeFootLogo = {
  96.2152, 118.26,
  "M 86.068,1 C 61.466,0 56.851,35.041 70.691,35.041 C 84.529,35.041 110.671,0 86.068,0 z "
  "M 45.217,30.699 C 52.586,31.149 60.671,2.577 46.821,4.374 C 32.976,6.171 37.845,30.249 45.217,30.699 z "
  "M 11.445,48.453 C 16.686,46.146 12.12,23.581 3.208,29.735 C -5.7,35.89 6.204,50.759 11.445,48.453 z "
  "M 26.212,36.642 C 32.451,35.37 32.793,9.778 21.667,14.369 C 10.539,18.961 19.978,37.916 26.212,36.642 L 26.212,36.642 z "
  "M 58.791,93.913 C 59.898,102.367 52.589,106.542 45.431,101.092 C 22.644,83.743 83.16,75.088 79.171,51.386 C 75.86,31.712 15.495,37.769 8.621,68.553 C 3.968,89.374 27.774,118.26 52.614,118.26 C 64.834,118.26 78.929,107.226 81.566,93.248 C 83.58,82.589 57.867,86.86 58.791,93.913 L 58.791,93.913 z "
  "\0"
};

static void
mini_svg_render (MiniSvg  *shape,
		 cairo_t  *cr,
		 gboolean  do_path)
{
  double x, y;
  const char *p;
  char op[2];
  int items, len;

  cairo_get_current_point (cr, &x, &y);
  cairo_translate (cr, x, y);

  for (p = shape->path; (items = sscanf (p, "%1s %n", op, &len)), p += len, *p;)
    switch (*op)
    {
      case 'M':
        {
	  sscanf (p, "%lf,%lf %n", &x, &y, &len); p += len;
	  cairo_move_to (cr, x, y);
	  break;
	}
      case 'L':
        {
	  sscanf (p, "%lf,%lf %n", &x, &y, &len); p += len;
	  cairo_line_to (cr, x, y);
	  break;
	}
      case 'C':
        {
	  double x1, y1, x2, y2, x3, y3;
	  sscanf (p, "%lf,%lf %lf,%lf %lf,%lf %n", &x1, &y1, &x2, &y2, &x3, &y3, &len); p += len;
	  cairo_curve_to (cr, x1, y1, x2, y2, x3, y3);
	  break;
	}
      case 'z':
        {
	  cairo_close_path (cr);
	  break;
	}
      default: 
        {
	  g_warning ("Invalid MiniSvg operation '%c'", *op);
	  break;
	}
    }

  if (!do_path)
    cairo_fill (cr);
}

static void
mini_svg_shape_renderer (cairo_t        *cr,
			 PangoAttrShape *attr,
			 gboolean        do_path,
			 gpointer        data)
{
  MiniSvg *shape = (MiniSvg *) attr->data;
  double scale_x, scale_y;

  scale_x = (double) attr->ink_rect.width  / (PANGO_SCALE * shape->width );
  scale_y = (double) attr->ink_rect.height / (PANGO_SCALE * shape->height);

  cairo_rel_move_to (cr,
		     (double) attr->ink_rect.x / PANGO_SCALE,
		     (double) attr->ink_rect.y / PANGO_SCALE);
  cairo_scale (cr, scale_x, scale_y);

  mini_svg_render (shape, cr, do_path);
}


static PangoLayout *
get_layout (cairo_t *cr)
{
  PangoLayout *layout;
  PangoAttrList *attrs;
  PangoRectangle ink_rect     = {1 * PANGO_SCALE, -11 * PANGO_SCALE,  8 * PANGO_SCALE, 10 * PANGO_SCALE};
  PangoRectangle logical_rect = {0 * PANGO_SCALE, -12 * PANGO_SCALE, 10 * PANGO_SCALE, 12 * PANGO_SCALE};
  const char *p;

  /* Create a PangoLayout, set the font and text */
  layout = pango_cairo_create_layout (cr);

  pango_cairo_context_set_shape_renderer (pango_layout_get_context (layout),
					  mini_svg_shape_renderer, NULL, NULL);

  pango_layout_set_text (layout, text, -1);

  attrs = pango_attr_list_new ();

  /* set gnome shape attributes for bullets */
  for (p = text; (p = strstr (p, BULLET)); p += strlen (BULLET))
    {
      PangoAttribute *attr;
      
      attr = pango_attr_shape_new_with_data (&ink_rect,
					     &logical_rect,
					     &GnomeFootLogo,
					     NULL, NULL);

      attr->start_index = p - text;
      attr->end_index = attr->start_index + strlen (BULLET);

      pango_attr_list_insert (attrs, attr);
    }

  pango_layout_set_attributes (layout, attrs);
  pango_attr_list_unref (attrs);

  return layout;
}

static void
draw_text (cairo_t *cr, int *width, int *height)
{

  PangoLayout *layout = get_layout (cr);

  if (width || height)
    {
      pango_layout_get_pixel_size (layout, width, height);
      if (width)
        *width += 20;
      if (height)
        *height += 20;
    }

  cairo_move_to (cr, 10, 10);
  pango_cairo_show_layout (cr, layout);

  g_object_unref (layout);
}

int main (int argc, char **argv)
{
  cairo_t *cr;
  char *filename;
  cairo_status_t status;
  cairo_surface_t *surface;
  int width, height;

  if (argc != 2)
    {
      g_printerr ("Usage: cairoshape OUTPUT_FILENAME\n");
      return 1;
    }

  filename = argv[1];

  surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
					0, 0);
  cr = cairo_create (surface);
  draw_text (cr, &width, &height);
  cairo_destroy (cr);
  cairo_surface_destroy (surface);

  surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
					width, height);
  cr = cairo_create (surface);

  cairo_set_source_rgb (cr, 1.0, 1.0, 1.0);
  cairo_paint (cr);
  cairo_set_source_rgb (cr, 0.0, 0.0, 0.5);
  draw_text (cr, NULL, NULL);
  cairo_destroy (cr);

  status = cairo_surface_write_to_png (surface, filename);
  cairo_surface_destroy (surface);

  if (status != CAIRO_STATUS_SUCCESS)
    {
      g_printerr ("Could not save png to '%s'\n", filename);
      return 1;
    }

  return 0;
}