pango.c.glyph source code

1 /*
2  * Distributed under the Boost Software License, Version 1.0.
3  *    (See accompanying file LICENSE_1_0.txt or copy at
4  *          http://www.boost.org/LICENSE_1_0.txt)
5  */
6 module pango.c.glyph;
7 
8 import pango.c.types;
9 import pango.c.item;
10 import pango.c.font;
11 
12 import glib;
13 import gobject;
14 
15 import std.bitmanip;
16 
17 extern (C):
18 
19 /* 1024ths of a device unit */
20 /**
21  * PangoGlyphUnit:
22  *
23  * The #PangoGlyphUnit type is used to store dimensions within
24  * Pango. Dimensions are stored in 1/%PANGO_SCALE of a device unit.
25  * (A device unit might be a pixel for screen display, or
26  * a point on a printer.) %PANGO_SCALE is currently 1024, and
27  * may change in the future (unlikely though), but you should not
28  * depend on its exact value. The PANGO_PIXELS() macro can be used
29  * to convert from glyph units into device units with correct rounding.
30  */
31 alias PangoGlyphUnit = gint32;
32 
33 /* Positioning information about a glyph
34  */
35 /**
36  * PangoGlyphGeometry:
37  * @width: the logical width to use for the the character.
38  * @x_offset: horizontal offset from nominal character position.
39  * @y_offset: vertical offset from nominal character position.
40  *
41  * The #PangoGlyphGeometry structure contains width and positioning
42  * information for a single glyph.
43  */
44 struct PangoGlyphGeometry
45 {
46   PangoGlyphUnit width;
47   PangoGlyphUnit x_offset;
48   PangoGlyphUnit y_offset;
49 }
50 
51 /* Visual attributes of a glyph
52  */
53 /**
54  * PangoGlyphVisAttr:
55  * @is_cluster_start: set for the first logical glyph in each cluster. (Clusters
56  * are stored in visual order, within the cluster, glyphs
57  * are always ordered in logical order, since visual
58  * order is meaningless; that is, in Arabic text, accent glyphs
59  * follow the glyphs for the base character.)
60  *
61  * The PangoGlyphVisAttr is used to communicate information between
62  * the shaping phase and the rendering phase.  More attributes may be
63  * added in the future.
64  */
65 struct PangoGlyphVisAttr
66 {
67     mixin(bitfields!(
68         guint, "is_cluster_start", 1,
69         guint, "", 7));
70 }
71 
72 /* A single glyph
73  */
74 /**
75  * PangoGlyphInfo:
76  * @glyph: the glyph itself.
77  * @geometry: the positional information about the glyph.
78  * @attr: the visual attributes of the glyph.
79  *
80  * The #PangoGlyphInfo structure represents a single glyph together with
81  * positioning information and visual attributes.
82  * It contains the following fields.
83  */
84 struct PangoGlyphInfo
85 {
86   PangoGlyph    glyph;
87   PangoGlyphGeometry geometry;
88   PangoGlyphVisAttr  attr;
89 }
90 
91 /* A string of glyphs with positional information and visual attributes -
92  * ready for drawing
93  */
94 /**
95  * PangoGlyphString:
96  *
97  * The #PangoGlyphString structure is used to store strings
98  * of glyphs with geometry and visual attribute information.
99  * The storage for the glyph information is owned
100  * by the structure which simplifies memory management.
101  */
102 struct PangoGlyphString {
103   gint num_glyphs;
104 
105   PangoGlyphInfo *glyphs;
106 
107   /* This is a memory inefficient way of representing the information
108    * here - each value gives the byte index within the text
109    * corresponding to the glyph string of the start of the cluster to
110    * which the glyph belongs.
111    */
112   gint *log_clusters;
113 
114   /*< private >*/
115   gint space;
116 }
117 
118 
119 PangoGlyphString *pango_glyph_string_new      ();
120 void              pango_glyph_string_set_size (PangoGlyphString *str,
121 					       gint              new_len);
122 pure GType             pango_glyph_string_get_type ();
123 PangoGlyphString *pango_glyph_string_copy     (PangoGlyphString *str);
124 void              pango_glyph_string_free     (PangoGlyphString *str);
125 void              pango_glyph_string_extents  (PangoGlyphString *glyphs,
126 					       PangoFont        *font,
127 					       PangoRectangle   *ink_rect,
128 					       PangoRectangle   *logical_rect);
129 int               pango_glyph_string_get_width(PangoGlyphString *glyphs);
130 
131 void              pango_glyph_string_extents_range  (PangoGlyphString *glyphs,
132 						     int               start,
133 						     int               end,
134 						     PangoFont        *font,
135 						     PangoRectangle   *ink_rect,
136 						     PangoRectangle   *logical_rect);
137 
138 void pango_glyph_string_get_logical_widths (PangoGlyphString *glyphs,
139 					    const(char)       *text,
140 					    int               length,
141 					    int               embedding_level,
142 					    int              *logical_widths);
143 
144 void pango_glyph_string_index_to_x (PangoGlyphString *glyphs,
145 				    char             *text,
146 				    int               length,
147 				    PangoAnalysis    *analysis,
148 				    int               index_,
149 				    gboolean          trailing,
150 				    int              *x_pos);
151 void pango_glyph_string_x_to_index (PangoGlyphString *glyphs,
152 				    char             *text,
153 				    int               length,
154 				    PangoAnalysis    *analysis,
155 				    int               x_pos,
156 				    int              *index_,
157 				    int              *trailing);
158 
159 /* Turn a string of characters into a string of glyphs
160  */
161 void pango_shape (const(gchar)      *text,
162 		  gint              length,
163 		  const(PangoAnalysis) *analysis,
164 		  PangoGlyphString *glyphs);
165 
166 void pango_shape_full (const(gchar)      *item_text,
167 		       gint              item_length,
168 		       const(gchar)      *paragraph_text,
169 		       gint              paragraph_length,
170 		       const(PangoAnalysis) *analysis,
171 		       PangoGlyphString *glyphs);
172 
173 GList *pango_reorder_items (GList *logical_items);
174