libresman: 026cdd1737ff examples/imgthumbs/src/main.c

libresman

view examples/imgthumbs/src/main.c @ 2:026cdd1737ff

added spaceball controls to the example and needless GLEW dependency

author	John Tsiombikas <nuclear@member.fsf.org>
date	Fri, 31 Jan 2014 03:40:00 +0200
parents	469ce01809bc
children	a396d43a62f9

line source

1 #include <stdio.h>

2 #include <stdlib.h>

3 #include <assert.h>

4 #include "opengl.h"

5 #include "resman.h"

6 #include "thumbs.h"

8 static int init(void);

9 static void cleanup(void);

10 static void display(void);

11 /*static void idle(void);*/

12 static void reshape(int x, int y);

13 static void keyb(unsigned char key, int x, int y);

14 static void mouse(int bn, int st, int x, int y);

15 static void motion(int x, int y);

16 static void sball_motion(int x, int y, int z);

17 static struct thumbnail *find_thumb(int x, int y);

19 const char *path = ".";

20 struct resman *texman;

21 int win_width, win_height;

22 float win_aspect;

23 float pan_x, pan_y;

24 float show_pan_x, show_pan_y;

25 float show_zoom = 1.0;

26 float thumbs_size = 0.25;

28 struct thumbnail *thumbs, *show_thumb;

30 int main(int argc, char **argv)

31 {

32 glutInit(&argc, argv);

34 if(argv[1]) {

35 path = argv[1];

36 }

38 glutInitWindowSize(800, 600);

39 glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);

40 glutCreateWindow("imgthumbs");

42 glutDisplayFunc(display);

43 glutReshapeFunc(reshape);

44 glutKeyboardFunc(keyb);

45 glutMouseFunc(mouse);

46 glutMotionFunc(motion);

47 glutSpaceballMotionFunc(sball_motion);

49 if(init() == -1) {

50 return 1;

51 }

52 atexit(cleanup);

54 glutMainLoop();

55 return 0;

56 }

58 static int init(void)

59 {

60 glewInit();

62 thumbs = create_thumbs(path);

63 return 0;

64 }

66 static void cleanup(void)

67 {

68 free_thumbs(thumbs);

69 }

71 static void display(void)

72 {

73 glClear(GL_COLOR_BUFFER_BIT);

75 glMatrixMode(GL_MODELVIEW);

76 glLoadIdentity();

78 if(show_thumb) {

79 glEnable(GL_TEXTURE_2D);

80 glBindTexture(GL_TEXTURE_2D, show_thumb->tex);

82 glScalef(show_zoom, show_zoom, 1);

83 glTranslatef(2.0 * show_pan_x, 2.0 * show_pan_y, 0);

84 if(show_thumb->aspect >= 1.0) {

85 glScalef(1, 1.0 / show_thumb->aspect, 1);

86 } else {

87 glScalef(show_thumb->aspect, 1, 1);

88 }

90 glBegin(GL_QUADS);

91 glColor3f(1, 1, 1);

92 glTexCoord2f(0, 0); glVertex2f(-1, -1);

93 glTexCoord2f(1, 0); glVertex2f(1, -1);

94 glTexCoord2f(1, 1); glVertex2f(1, 1);

95 glTexCoord2f(0, 1); glVertex2f(-1, 1);

96 glEnd();

98 glDisable(GL_TEXTURE_2D);

99 } else {

100 draw_thumbs(thumbs, thumbs_size, pan_y);

101 }

102

103 glutSwapBuffers();

104 assert(glGetError() == GL_NO_ERROR);

105 }

106

107 /*

108 static void idle(void)

109 {

110 glutPostRedisplay();

111 }

112 */

113

114 static void reshape(int x, int y)

115 {

116 win_aspect = (float)x / (float)y;

117

118 glViewport(0, 0, x, y);

119

120 glMatrixMode(GL_PROJECTION);

121 glLoadIdentity();

122 glOrtho(-1, 1, 1.0 / win_aspect, -1.0 / win_aspect, -1, 1);

123

124 win_width = x;

125 win_height = y;

126 }

127

128 static void keyb(unsigned char key, int x, int y)

129 {

130 switch(key) {

131 case 27:

132 exit(0);

133

134 case ' ':

135 show_zoom = 1.0;

136 thumbs_size = 0.25;

137 pan_x = pan_y = show_pan_x = show_pan_y = 0;

138 glutPostRedisplay();

139 break;

140 }

141 }

142

143 static int bnstate[32];

144 static int prev_x, prev_y;

145 static int click_x[32], click_y[32];

146

147 static void mouse(int bn, int st, int x, int y)

148 {

149 int bidx = bn - GLUT_LEFT_BUTTON;

150 int state = st == GLUT_DOWN ? 1 : 0;

151

152 bnstate[bidx] = state;

153

154 prev_x = x;

155 prev_y = y;

156

157 if(state) {

158 click_x[bidx] = x;

159 click_y[bidx] = y;

160 } else {

161 int is_drag = abs(x - click_x[bidx]) > 3 || abs(y - click_y[bidx]) > 3;

162

163 if(bidx == 0) {

164 if(!show_thumb) {

165 if(!is_drag) {

166 struct thumbnail *sel = find_thumb(x, y);

167 if(sel) {

168 show_thumb = sel;

169 show_pan_x = show_pan_y = 0;

170 glutPostRedisplay();

171 }

172 }

173 }

174 } else {

175 if(!is_drag) {

176 show_thumb = 0;

177 glutPostRedisplay();

178 }

179 }

180 }

181 }

182

183 static void motion(int x, int y)

184 {

185 int dx = x - prev_x;

186 int dy = y - prev_y;

187 prev_x = x;

188 prev_y = y;

189

190 if(!dx && !dy) return;

191

192 if(bnstate[0]) {

193 float fdx = dx / (float)win_width;

194 float fdy = dy / (float)win_height / win_aspect;

195

196 if(show_thumb) {

197 show_pan_x += fdx / show_zoom;

198 show_pan_y += fdy / show_zoom;

199 } else {

200 pan_x += fdx;

201 pan_y += fdy;

202 }

203 glutPostRedisplay();

204 }

205

206 if(bnstate[2]) {

207 if(show_thumb) {

208 show_zoom -= dy * 0.0075;

209 if(show_zoom <= 0) show_zoom = 0;

210 } else {

211 thumbs_size -= dy * 0.005;

212 if(thumbs_size <= 0.01) thumbs_size = 0.01;

213 }

214 glutPostRedisplay();

215 }

216 }

217

218 static void sball_motion(int x, int y, int z)

219 {

220 float fx = -x * 0.0004;

221 float fy = z * 0.0004;

222 float fz = -y * 0.0005;

223

224 if(show_thumb) {

225 show_pan_x += fx / show_zoom;

226 show_pan_y += fy / show_zoom;

227 show_zoom += fz;

228 if(show_zoom <= 0) show_zoom = 0;

229 } else {

230 pan_x += fx;

231 pan_y += fy;

232 thumbs_size += fz;

233 if(thumbs_size <= 0.01) thumbs_size = 0.01;

234 }

235 glutPostRedisplay();

236 }

237

238 static struct thumbnail *find_thumb(int x, int y)

239 {

240 float fx = (float)x / (float)win_width;

241 float fy = (float)y / (float)win_height / win_aspect;

242 struct thumbnail *node;

243

244 node = thumbs;

245 while(node) {

246 float nx = node->layout_pos[0];

247 float ny = node->layout_pos[1];

248

249 if(fx >= nx && fx < nx + node->layout_size[0] &&

250 fy >= ny && fy < ny + node->layout_size[1]) {

251 return node;

252 }

253 node = node->next;

254 }

255 return 0;

256 }