volray: a6765984e057 src/volray.c

volray

view src/volray.c @ 9:a6765984e057

moved the volume loading to volume.c

author	John Tsiombikas <nuclear@member.fsf.org>
date	Sun, 08 Apr 2012 07:11:54 +0300
parents	f40e4edfee7e
children

line source

1 #include <stdio.h>

2 #include <stdlib.h>

3 #include <assert.h>

5 #include <GL/glew.h>

6 #ifndef __APPLE__

7 #include <GL/glut.h>

8 #else

9 #include <GLUT/glut.h>

10 #endif

12 #include <vmath/vmath.h>

13 #include <imago2.h>

14 #include "sdr.h"

15 #include "volume.h"

17 #define XFER_MAP_SZ 512

19 enum {

20 UIMODE_DEFAULT,

21 UIMODE_XFER,

22 UIMODE_CURSOR

23 };

25 int init(void);

26 void disp(void);

27 void render_volume(void);

28 void draw_slice(void);

29 void draw_xfer_func(void);

30 void reshape(int x, int y);

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

32 void keyb_up(unsigned char key, int x, int y);

33 void mouse(int bn, int state, int x, int y);

34 void motion(int x, int y);

35 int parse_args(int argc, char **argv);

37 static void create_ray_texture(int xsz, int ysz, float vfov, vec2_t *tex_scale);

38 static vec3_t get_primary_ray_dir(int x, int y, int w, int h, float vfov_deg);

39 static int round_pow2(int x);

40 static void create_transfer_map(float mean, float sdev);

42 static float cam_theta = 0, cam_phi = 0, cam_dist = 4.0;

43 static float cam_x, cam_y, cam_z;

45 static vec2_t tex_scale;

46 static struct volume *volume;

47 static unsigned int vol_sdr, slice_sdr, ray_tex;

48 static int win_xsz, win_ysz;

49 static int raytex_needs_recalc = 1;

51 static unsigned int xfer_tex;

52 static float xfer_mean = 0.7, xfer_sdev = 0.1;

53 static int xfertex_needs_recalc = 1;

55 static int uimode;

56 static float cur_z = 0.0;

57 static float ray_step = 0.01;

59 static const char *fname;

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

63 {

64 glutInit(&argc, argv);

65 glutInitWindowSize(1280, 720);

66 glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);

68 if(parse_args(argc, argv) == -1) {

69 return 1;

70 }

72 glutCreateWindow("Volume Raytracer");

74 glutDisplayFunc(disp);

75 glutReshapeFunc(reshape);

76 glutKeyboardFunc(keyb);

77 glutKeyboardUpFunc(keyb_up);

78 glutMouseFunc(mouse);

79 glutMotionFunc(motion);

81 glewInit();

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

84 return 1;

85 }

87 glutMainLoop();

88 return 0;

89 }

91 int init(void)

92 {

93 if(!(vol_sdr = create_program_load("sdr/volray.v.glsl", "sdr/volray.p.glsl"))) {

94 return -1;

95 }

96 set_uniform_int(vol_sdr, "volume", 0);

97 set_uniform_int(vol_sdr, "ray_tex", 1);

98 set_uniform_int(vol_sdr, "xfer_tex", 2);

99 set_uniform_float(vol_sdr, "ray_step", ray_step);

100 set_uniform_float(vol_sdr, "zclip", cur_z);

101

102 if(!(slice_sdr = create_program_load(0, "sdr/slice.p.glsl"))) {

103 return -1;

104 }

105 set_uniform_int(slice_sdr, "volume", 0);

106 set_uniform_int(slice_sdr, "xfer_tex", 1);

107

108 if(!(volume = load_volume(fname))) {

109 return -1;

110 }

111

112 return 0;

113 }

114

115 void disp(void)

116 {

117 /* recalculate primary ray texture if needed */

118 if(raytex_needs_recalc) {

119 create_ray_texture(win_xsz, win_ysz, 50.0, &tex_scale);

120 }

121 /* recalculate transfer function texture if needed */

122 if(xfertex_needs_recalc) {

123 create_transfer_map(xfer_mean, xfer_sdev);

124 }

125

126 render_volume();

127 draw_slice();

128 draw_xfer_func();

129

130 glutSwapBuffers();

131 assert(glGetError() == GL_NO_ERROR);

132 }

133

134 void render_volume(void)

135 {

136 /* set the camera transformation */

137 glMatrixMode(GL_MODELVIEW);

138 glPushMatrix();

139 glLoadIdentity();

140 glRotatef(-90, 1, 0, 0);

141 glTranslatef(cam_x, cam_y, -cam_z);

142 glRotatef(cam_theta, 0, 1, 0);

143 glRotatef(cam_phi, 1, 0, 0);

144 glTranslatef(0, 0, -cam_dist);

145

146 /* setup the texture matrix to map the useful part of the ray texture to [0,1] */

147 glMatrixMode(GL_TEXTURE);

148 glPushMatrix();

149 glLoadIdentity();

150 glScalef(tex_scale.x, tex_scale.y, 1.0);

151

152 /* tex unit0: volume data 3D texture */

153 glActiveTexture(GL_TEXTURE0);

154 glBindTexture(GL_TEXTURE_3D, volume->tex_vol);

155 glEnable(GL_TEXTURE_3D);

156

157 /* tex unit1: primary rays in view space */

158 glActiveTexture(GL_TEXTURE1);

159 glBindTexture(GL_TEXTURE_2D, ray_tex);

160 glEnable(GL_TEXTURE_2D);

161

162 /* tex unit2: transfer function (1d) */

163 glActiveTexture(GL_TEXTURE2);

164 glBindTexture(GL_TEXTURE_1D, xfer_tex);

165 glEnable(GL_TEXTURE_1D);

166

167 bind_program(vol_sdr);

168 glBegin(GL_QUADS);

169 glColor3f(1, 1, 1);

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

171 glTexCoord2f(1, 1); glVertex2f(1, -1);

172 glTexCoord2f(1, 0); glVertex2f(1, 1);

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

174 glEnd();

175 bind_program(0);

176

177 glActiveTexture(GL_TEXTURE2);

178 glDisable(GL_TEXTURE_1D);

179 glActiveTexture(GL_TEXTURE1);

180 glDisable(GL_TEXTURE_2D);

181 glActiveTexture(GL_TEXTURE0);

182 glDisable(GL_TEXTURE_3D);

183

184 glMatrixMode(GL_TEXTURE);

185 glPopMatrix();

186 glMatrixMode(GL_MODELVIEW);

187 glPopMatrix();

188 }

189

190 void draw_slice(void)

191 {

192 glMatrixMode(GL_MODELVIEW);

193 glPushMatrix();

194 glTranslatef(0.9, 0.9, 0);

195 glScalef(0.3, 0.3 * ((float)win_xsz / win_ysz), 1);

196 glTranslatef(-1, -1, 0);

197

198 glActiveTexture(GL_TEXTURE0);

199 glBindTexture(GL_TEXTURE_3D, volume->tex_vol);

200 glEnable(GL_TEXTURE_3D);

201

202 glActiveTexture(GL_TEXTURE1);

203 glBindTexture(GL_TEXTURE_1D, xfer_tex);

204 glEnable(GL_TEXTURE_1D);

205

206 bind_program(slice_sdr);

207

208 glBegin(GL_QUADS);

209 glColor3f(1, 1, 1);

210 glTexCoord3f(0, 1, cur_z); glVertex2f(-1, -1);

211 glTexCoord3f(1, 1, cur_z); glVertex2f(1, -1);

212 glTexCoord3f(1, 0, cur_z); glVertex2f(1, 1);

213 glTexCoord3f(0, 0, cur_z); glVertex2f(-1, 1);

214 glEnd();

215

216 bind_program(0);

217

218 glActiveTexture(GL_TEXTURE1);

219 glDisable(GL_TEXTURE_1D);

220 glActiveTexture(GL_TEXTURE0);

221 glDisable(GL_TEXTURE_3D);

222 glPopMatrix();

223 }

224

225 void draw_xfer_func(void)

226 {

227 glMatrixMode(GL_MODELVIEW);

228 glPushMatrix();

229 glTranslatef(-0.9, -0.9, 0);

230 glScalef(0.5, 0.1, 1);

231

232 glBindTexture(GL_TEXTURE_1D, xfer_tex);

233 glEnable(GL_TEXTURE_1D);

234

235 glBegin(GL_QUADS);

236 glColor3f(1, 1, 1);

237 glTexCoord1f(1);

238 glVertex2f(1, 0);

239 glVertex2f(1, 1);

240 glTexCoord1f(0);

241 glVertex2f(0, 1);

242 glVertex2f(0, 0);

243 glEnd();

244

245 glDisable(GL_TEXTURE_1D);

246

247 glLineWidth(2.0);

248 glBegin(GL_LINE_LOOP);

249 if(uimode == UIMODE_XFER) {

250 glColor3f(1, 0, 0);

251 } else {

252 glColor3f(0, 0, 1);

253 }

254 glVertex2f(0, 0);

255 glVertex2f(1, 0);

256 glVertex2f(1, 1);

257 glVertex2f(0, 1);

258 glEnd();

259

260 glPopMatrix();

261 }

262

263 void reshape(int x, int y)

264 {

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

266

267 if(x != win_xsz || y != win_ysz) {

268 raytex_needs_recalc = 1;

269 win_xsz = x;

270 win_ysz = y;

271 }

272 }

273

274 void keyb(unsigned char key, int x, int y)

275 {

276 switch(key) {

277 case 27:

278 exit(0);

279

280 case 'x':

281 uimode = UIMODE_XFER;

282 glutPostRedisplay();

283 break;

284

285 case 'c':

286 uimode = UIMODE_CURSOR;

287 glutPostRedisplay();

288 break;

289

290 default:

291 break;

292 }

293 }

294

295 void keyb_up(unsigned char key, int x, int y)

296 {

297 switch(key) {

298 case 'x':

299 if(uimode == UIMODE_XFER) {

300 uimode = UIMODE_DEFAULT;

301 glutPostRedisplay();

302 }

303 break;

304

305 case 'c':

306 if(uimode == UIMODE_CURSOR) {

307 uimode = UIMODE_DEFAULT;

308 glutPostRedisplay();

309 }

310 break;

311

312 default:

313 break;

314 }

315 }

316

317 static int bnstate[32];

318 static int prev_x, prev_y;

319

320 void mouse(int bn, int state, int x, int y)

321 {

322 bnstate[bn - GLUT_LEFT_BUTTON] = state == GLUT_DOWN;

323 prev_x = x;

324 prev_y = y;

325 }

326

327 void motion(int x, int y)

328 {

329 int dx = x - prev_x;

330 int dy = y - prev_y;

331 prev_x = x;

332 prev_y = y;

333

334 switch(uimode) {

335 case UIMODE_XFER:

336 if(dx || dy) {

337 xfer_mean += dx / (float)win_xsz;

338 xfer_sdev += 0.5 * dy / (float)win_ysz;

339

340 xfer_mean = xfer_mean < 0.0 ? 0.0 : (xfer_mean > 1.0 ? 1.0 : xfer_mean);

341 xfer_sdev = xfer_sdev < 0.0 ? 0.0 : (xfer_sdev > 1.0 ? 1.0 : xfer_sdev);

342

343 xfertex_needs_recalc = 1;

344 glutPostRedisplay();

345 }

346 break;

347

348 case UIMODE_CURSOR:

349 cur_z += 0.5 * dy / (float)win_ysz;

350

351 if(cur_z < 0.0)

352 cur_z = 0.0;

353 if(cur_z > 1.0)

354 cur_z = 1.0;

355

356 set_uniform_float(vol_sdr, "zclip", cur_z);

357 glutPostRedisplay();

358 break;

359

360 default:

361 /* view control */

362 if(bnstate[0]) {

363 cam_theta += dx * 0.5;

364 cam_phi += dy * 0.5;

365

366 if(cam_phi <= -90) cam_phi = -89;

367 if(cam_phi >= 90) cam_phi = 89;

368

369 glutPostRedisplay();

370 }

371

372 if(bnstate[1]) {

373 cam_x += dx * 0.025;

374 cam_y += dy * 0.025;

375 glutPostRedisplay();

376 }

377

378 if(bnstate[2]) {

379 cam_dist += dy * 0.025;

380 if(cam_dist < 0.0) cam_dist = 0.0;

381 glutPostRedisplay();

382 }

383 }

384 }

385

386

387 int parse_args(int argc, char **argv)

388 {

389 int i;

390 char *endp;

391

392 for(i=1; i<argc; i++) {

393 if(argv[i][0] == '-' && argv[i][2] == 0) {

394 switch(argv[i][1]) {

395 case 'm':

396 xfer_mean = strtod(argv[++i], &endp);

397 if(endp == argv[i]) {

398 fprintf(stderr, "-m must be followed by the transfer function mean\n");

399 return -1;

400 }

401 break;

402

403 case 'd':

404 xfer_sdev = strtod(argv[++i], &endp);

405 if(endp == argv[i]) {

406 fprintf(stderr, "-d must be followed by the transfer function std.deviation\n");

407 return -1;

408 }

409 break;

410

411 default:

412 fprintf(stderr, "unrecognized option: %s\n", argv[i]);

413 return -1;

414 }

415 } else {

416 if(fname) {

417 fprintf(stderr, "unexpected argument: %s\n", argv[i]);

418 return -1;

419 }

420 fname = argv[i];

421 }

422 }

423

424 if(!fname) {

425 fprintf(stderr, "pass the volume descriptor filename\n");

426 return -1;

427 }

428 return 0;

429 }

430

431

432 static void create_ray_texture(int xsz, int ysz, float vfov, vec2_t *tex_scale)

433 {

434 int i, j;

435 int cur_tex_xsz, cur_tex_ysz;

436 int tex_xsz = round_pow2(xsz);

437 int tex_ysz = round_pow2(ysz);

438 float *teximg, *dir;

439

440 if(!(teximg = malloc(3 * xsz * ysz * sizeof *teximg))) {

441 return;

442 }

443 dir = teximg;

444

445 for(i=0; i<ysz; i++) {

446 for(j=0; j<xsz; j++) {

447 vec3_t rdir = get_primary_ray_dir(j, i, xsz, ysz, vfov);

448 *dir++ = rdir.x;

449 *dir++ = rdir.y;

450 *dir++ = rdir.z;

451 }

452 }

453

454 if(!ray_tex) {

455 glGenTextures(1, &ray_tex);

456 }

457

458 glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_WIDTH, &cur_tex_xsz);

459 glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_HEIGHT, &cur_tex_ysz);

460

461 if(tex_xsz > cur_tex_xsz || tex_ysz > cur_tex_ysz) {

462 glBindTexture(GL_TEXTURE_2D, ray_tex);

463 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

464 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

465 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);

466 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);

467 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB32F_ARB, tex_xsz, tex_ysz, 0, GL_RGB, GL_FLOAT, 0);

468 }

469

470 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, xsz, ysz, GL_RGB, GL_FLOAT, teximg);

471 free(teximg);

472

473 if(tex_scale) {

474 tex_scale->x = (float)xsz / (float)tex_xsz;

475 tex_scale->y = (float)ysz / (float)tex_ysz;

476 }

477 raytex_needs_recalc = 0;

478 }

479

480 static vec3_t get_primary_ray_dir(int x, int y, int w, int h, float vfov_deg)

481 {

482 float vfov = M_PI * vfov_deg / 180.0;

483 float aspect = (float)w / (float)h;

484

485 float ysz = 2.0;

486 float xsz = aspect * ysz;

487

488 float px = ((float)x / (float)w) * xsz - xsz / 2.0;

489 float py = 1.0 - ((float)y / (float)h) * ysz;

490 float pz = 1.0 / tan(0.5 * vfov);

491

492 float mag = sqrt(px * px + py * py + pz * pz);

493

494 return v3_cons(px / mag, py / mag, pz / mag);

495 }

496

497 static int round_pow2(int x)

498 {

499 x--;

500 x = (x >> 1) | x;

501 x = (x >> 2) | x;

502 x = (x >> 4) | x;

503 x = (x >> 8) | x;

504 x = (x >> 16) | x;

505 return x + 1;

506 }

507

508 static void create_transfer_map(float mean, float sdev)

509 {

510 static float map[XFER_MAP_SZ];

511 int i;

512

513 if(!xfer_tex) {

514 glGenTextures(1, &xfer_tex);

515 glBindTexture(GL_TEXTURE_1D, xfer_tex);

516 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

517 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

518 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);

519 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

520 glTexImage1D(GL_TEXTURE_1D, 0, GL_LUMINANCE32F_ARB, XFER_MAP_SZ, 0, GL_LUMINANCE, GL_FLOAT, 0);

521 }

522

523 for(i=0; i<XFER_MAP_SZ; i++) {

524 float x = (float)i / (float)(XFER_MAP_SZ - 1);

525 map[i] = gaussian(x, mean, sdev) - 1.0;

526 }

527 putchar('\n');

528

529 glTexSubImage1D(GL_TEXTURE_1D, 0, 0, XFER_MAP_SZ, GL_LUMINANCE, GL_FLOAT, map);

530 xfertex_needs_recalc = 0;

531 }