1 /* dropshadow.c, Copyright (c) 2009 Jens Kilian <jjk@acm.org>
3 * Permission to use, copy, modify, distribute, and sell this software and its
4 * documentation for any purpose is hereby granted without fee, provided that
5 * the above copyright notice appear in all copies and that both that
6 * copyright notice and this permission notice appear in supporting
7 * documentation. No representations are made about the suitability of this
8 * software for any purpose. It is provided "as is" without express or
14 #endif /* HAVE_CONFIG_H */
18 #include "dropshadow.h"
20 /* (Alpha) texture data for drop shadow.
22 static int drop_shadow_width = 32;
23 static int drop_shadow_height = 32;
24 static unsigned char drop_shadow_data[] =
26 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
27 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
28 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0,
29 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0,
30 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
31 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,
32 0, 0, 0, 0, 0, 1, 1, 1, 3, 3, 4, 4, 4, 4, 4, 4,
33 4, 4, 4, 4, 4, 4, 3, 3, 1, 1, 1, 0, 0, 0, 0, 0,
34 0, 0, 0, 0, 1, 1, 3, 4, 6, 7, 9, 10, 10, 10, 10, 10,
35 10, 10, 10, 10, 10, 9, 7, 6, 4, 3, 1, 1, 0, 0, 0, 0,
36 0, 0, 0, 1, 1, 3, 5, 9, 13, 16, 19, 19, 21, 21, 22, 22,
37 22, 22, 21, 21, 19, 19, 16, 13, 9, 5, 3, 1, 1, 0, 0, 0,
38 0, 0, 1, 1, 3, 5, 10, 16, 22, 28, 32, 35, 37, 37, 38, 38,
39 38, 38, 37, 37, 35, 32, 28, 22, 16, 10, 5, 3, 1, 1, 0, 0,
40 0, 0, 1, 1, 4, 9, 16, 25, 34, 43, 50, 55, 58, 59, 60, 60,
41 60, 60, 59, 58, 55, 50, 43, 34, 25, 16, 9, 4, 1, 1, 0, 0,
42 0, 0, 1, 3, 6, 13, 22, 34, 48, 61, 70, 77, 80, 82, 83, 84,
43 84, 83, 82, 80, 77, 70, 61, 48, 34, 22, 13, 6, 3, 1, 0, 0,
44 0, 0, 1, 3, 7, 16, 28, 43, 61, 76, 88, 97, 102, 103, 104, 104,
45 104, 104, 103, 102, 97, 88, 76, 61, 43, 28, 16, 7, 3, 1, 0, 0,
46 0, 1, 1, 4, 9, 19, 32, 51, 70, 88, 103, 112, 117, 120, 121, 121,
47 121, 121, 120, 117, 112, 103, 88, 70, 51, 32, 19, 9, 4, 1, 1, 0,
48 0, 1, 1, 4, 10, 20, 35, 55, 77, 97, 112, 122, 128, 130, 132, 133,
49 133, 132, 130, 128, 122, 112, 97, 77, 55, 35, 20, 10, 4, 1, 1, 0,
50 0, 1, 1, 4, 10, 21, 37, 58, 80, 101, 117, 128, 134, 137, 138, 139,
51 139, 138, 137, 134, 128, 117, 101, 80, 58, 37, 21, 10, 4, 1, 0, 0,
52 0, 0, 1, 4, 10, 21, 38, 59, 82, 103, 119, 130, 137, 139, 141, 142,
53 142, 141, 139, 137, 130, 119, 103, 82, 59, 38, 21, 10, 4, 1, 0, 0,
54 0, 0, 1, 4, 10, 22, 38, 59, 83, 104, 121, 132, 139, 141, 142, 142,
55 142, 142, 141, 139, 132, 121, 104, 83, 59, 38, 22, 10, 4, 1, 0, 0,
56 0, 0, 1, 4, 10, 22, 38, 60, 84, 104, 121, 133, 139, 142, 142, 142,
57 142, 142, 142, 139, 133, 121, 104, 84, 60, 38, 22, 10, 4, 1, 0, 0,
58 0, 0, 1, 4, 10, 22, 38, 60, 84, 104, 121, 133, 139, 142, 142, 142,
59 142, 142, 142, 139, 133, 121, 104, 84, 60, 38, 22, 10, 4, 1, 0, 0,
60 0, 0, 1, 4, 10, 22, 38, 59, 83, 104, 121, 132, 139, 141, 142, 142,
61 142, 142, 141, 139, 132, 121, 104, 83, 59, 38, 22, 10, 4, 1, 0, 0,
62 0, 0, 1, 4, 10, 21, 38, 59, 82, 103, 119, 130, 137, 139, 141, 142,
63 142, 141, 139, 137, 130, 119, 103, 82, 59, 38, 21, 10, 4, 1, 0, 0,
64 0, 1, 1, 4, 10, 21, 37, 58, 80, 101, 118, 128, 134, 137, 139, 139,
65 139, 139, 137, 134, 128, 117, 102, 80, 58, 37, 21, 10, 4, 1, 0, 0,
66 0, 1, 1, 4, 10, 20, 35, 55, 77, 97, 112, 122, 128, 130, 132, 133,
67 133, 132, 130, 128, 122, 112, 97, 77, 55, 35, 20, 10, 4, 1, 1, 0,
68 0, 1, 1, 4, 9, 19, 32, 51, 70, 88, 103, 112, 117, 120, 121, 121,
69 121, 121, 120, 117, 112, 103, 88, 70, 51, 32, 19, 9, 4, 1, 1, 0,
70 0, 0, 1, 3, 7, 16, 28, 43, 61, 76, 88, 97, 102, 103, 104, 104,
71 104, 104, 103, 102, 97, 88, 76, 61, 43, 28, 16, 7, 3, 1, 0, 0,
72 0, 0, 1, 3, 6, 13, 22, 34, 48, 61, 70, 77, 80, 82, 83, 84,
73 84, 83, 82, 80, 77, 70, 61, 48, 34, 22, 13, 6, 3, 1, 0, 0,
74 0, 0, 1, 1, 4, 9, 16, 25, 34, 43, 50, 55, 58, 59, 60, 60,
75 60, 60, 59, 58, 55, 50, 43, 34, 25, 16, 9, 4, 1, 1, 0, 0,
76 0, 0, 1, 1, 3, 5, 10, 16, 22, 28, 32, 35, 37, 37, 38, 38,
77 38, 38, 37, 37, 35, 32, 28, 22, 16, 10, 5, 3, 1, 1, 0, 0,
78 0, 0, 0, 1, 1, 3, 5, 9, 13, 16, 19, 19, 21, 21, 22, 22,
79 22, 22, 21, 21, 19, 19, 16, 13, 9, 5, 3, 1, 1, 0, 0, 0,
80 0, 0, 0, 0, 1, 1, 3, 4, 6, 7, 9, 10, 10, 10, 10, 10,
81 10, 10, 10, 10, 10, 9, 7, 6, 4, 3, 1, 1, 0, 0, 0, 0,
82 0, 0, 0, 0, 0, 1, 1, 1, 3, 3, 4, 4, 4, 4, 4, 4,
83 4, 4, 4, 4, 4, 4, 3, 3, 1, 1, 1, 0, 0, 0, 0, 0,
84 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
85 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,
86 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0,
87 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0,
88 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
89 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
93 init_drop_shadow(void)
97 glGenTextures (1, &t);
100 glBindTexture (GL_TEXTURE_2D, t);
102 glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
103 glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
104 gluBuild2DMipmaps (GL_TEXTURE_2D, GL_ALPHA,
105 drop_shadow_width, drop_shadow_height,
106 GL_ALPHA, GL_UNSIGNED_BYTE,
109 glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
110 glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
111 glTexImage2D (GL_TEXTURE_2D, 0, GL_ALPHA,
112 drop_shadow_width, drop_shadow_height, 0,
113 GL_ALPHA, GL_UNSIGNED_BYTE,
121 draw_drop_shadow (GLuint t,
122 GLfloat x, GLfloat y, GLfloat z, GLfloat w, GLfloat h,
125 /* Inner and outer boundaries of shadow. */
126 const GLfloat li = x, lo = li - r;
127 const GLfloat ri = x + w, ro = ri + r;
128 const GLfloat bi = y, bo = bi - r;
129 const GLfloat ti = y + h, to = ti + r;
132 glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
134 glEnable (GL_TEXTURE_2D);
135 glBindTexture (GL_TEXTURE_2D, t);
139 /* There's likely a better way to do this... */
140 glTexCoord2f (0.0, 0.0); glVertex3f (lo, bo, z);
141 glTexCoord2f (0.5, 0.0); glVertex3f (li, bo, z);
142 glTexCoord2f (0.5, 0.5); glVertex3f (li, bi, z);
143 glTexCoord2f (0.0, 0.5); glVertex3f (lo, bi, z);
145 glTexCoord2f (0.5, 0.0); glVertex3f (li, bo, z);
146 glTexCoord2f (0.5, 0.0); glVertex3f (ri, bo, z);
147 glTexCoord2f (0.5, 0.5); glVertex3f (ri, bi, z);
148 glTexCoord2f (0.5, 0.5); glVertex3f (li, bi, z);
150 glTexCoord2f (0.5, 0.0); glVertex3f (ri, bo, z);
151 glTexCoord2f (1.0, 0.0); glVertex3f (ro, bo, z);
152 glTexCoord2f (1.0, 0.5); glVertex3f (ro, bi, z);
153 glTexCoord2f (0.5, 0.5); glVertex3f (ri, bi, z);
155 glTexCoord2f (0.5, 0.5); glVertex3f (ri, bi, z);
156 glTexCoord2f (1.0, 0.5); glVertex3f (ro, bi, z);
157 glTexCoord2f (1.0, 0.5); glVertex3f (ro, ti, z);
158 glTexCoord2f (0.5, 0.5); glVertex3f (ri, ti, z);
160 glTexCoord2f (0.5, 0.5); glVertex3f (ri, ti, z);
161 glTexCoord2f (1.0, 0.5); glVertex3f (ro, ti, z);
162 glTexCoord2f (1.0, 1.0); glVertex3f (ro, to, z);
163 glTexCoord2f (0.5, 1.0); glVertex3f (ri, to, z);
165 glTexCoord2f (0.5, 0.5); glVertex3f (li, ti, z);
166 glTexCoord2f (0.5, 0.5); glVertex3f (ri, ti, z);
167 glTexCoord2f (0.5, 1.0); glVertex3f (ri, to, z);
168 glTexCoord2f (0.5, 1.0); glVertex3f (li, to, z);
170 glTexCoord2f (0.0, 0.5); glVertex3f (lo, ti, z);
171 glTexCoord2f (0.5, 0.5); glVertex3f (li, ti, z);
172 glTexCoord2f (0.5, 1.0); glVertex3f (li, to, z);
173 glTexCoord2f (0.0, 1.0); glVertex3f (lo, to, z);
175 glTexCoord2f (0.0, 0.5); glVertex3f (lo, bi, z);
176 glTexCoord2f (0.5, 0.5); glVertex3f (li, bi, z);
177 glTexCoord2f (0.5, 0.5); glVertex3f (li, ti, z);
178 glTexCoord2f (0.0, 0.5); glVertex3f (lo, ti, z);