qvolray: 2d0dfb5751dc src/volray.cc

qvolray

view src/volray.cc @ 22:2d0dfb5751dc

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author	John Tsiombikas <nuclear@member.fsf.org>
date	Wed, 11 Apr 2012 18:35:12 +0300
parents	4c62be57fc1a
children	53aca4775514

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"

16 #include "ui.h"

17 #include "demo.h"

19 #define XFER_MAP_SZ 512

21 static void render_volume();

22 static void draw_slice();

23 static void draw_xfer_func();

25 /*

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

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

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

29 void motion(int x, int y);

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

31 */

33 static void create_ray_texture(int xsz, int ysz, float vfov, Vector2 *tex_scale);

34 static Vector3 get_primary_ray_dir(int x, int y, int w, int h, float vfov_deg);

35 static int round_pow2(int x);

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

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

39 static float cam_x, cam_y, cam_z;

41 static Vector2 tex_scale;

42 static unsigned int vol_sdr, slice_sdr, ray_tex;

43 static int win_xsz, win_ysz;

44 static bool raytex_needs_recalc = true;

46 static unsigned int xfer_tex;

47 static float xfer_mean = 0.7, xfer_sdev = 0.1;

48 static bool xfertex_needs_recalc = true;

50 static float cur_z = 0.5;

51 static float ray_step = 0.01;

53 static Volume *volume;

56 bool volray_init()

57 {

58 glewInit();

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

61 return false;

62 }

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

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

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

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

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

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

70 return false;

71 }

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

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

75 init_demo();

77 return true;

78 }

80 void volray_setvolume(Volume *vol)

81 {

82 volume = vol;

83 }

85 Volume *volray_getvolume()

86 {

87 return volume;

88 }

90 void volray_setvalue(int which, float val)

91 {

92 switch(which) {

93 case VOLRAY_ZCURSOR:

94 cur_z = val;

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

96 post_redisplay();

97 break;

99 case VOLRAY_ZCLIP:

100

101 default:

102 break;

103 }

104 }

105

106 float volray_getvalue(int which)

107 {

108 switch(which) {

109 case VOLRAY_ZCURSOR:

110 return cur_z;

111

112 default:

113 break;

114 }

115 return 0.0;

116 }

117

118 void volray_draw(void)

119 {

120 /* recalculate primary ray texture if needed */

121 if(raytex_needs_recalc) {

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

123 }

124 /* recalculate transfer function texture if needed */

125 if(xfertex_needs_recalc) {

126 create_transfer_map(xfer_mean, xfer_sdev);

127 }

128

129 draw_demo();

130

131 glClear(GL_COLOR_BUFFER_BIT);

132

133 if(volume) {

134 render_volume();

135 draw_slice();

136 draw_xfer_func();

137 }

138

139 assert(glGetError() == GL_NO_ERROR);

140 }

141

142 static void render_volume(void)

143 {

144 /* set the camera transformation */

145 glMatrixMode(GL_MODELVIEW);

146 glPushMatrix();

147 glLoadIdentity();

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

149 glTranslatef(cam_x, cam_y, -cam_z);

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

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

152 glTranslatef(0, 0, -cam_dist);

153

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

155 glMatrixMode(GL_TEXTURE);

156 glPushMatrix();

157 glLoadIdentity();

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

159

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

161 glActiveTexture(GL_TEXTURE0);

162 glBindTexture(GL_TEXTURE_3D, volume->get_texture());

163 glEnable(GL_TEXTURE_3D);

164

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

166 glActiveTexture(GL_TEXTURE1);

167 glBindTexture(GL_TEXTURE_2D, ray_tex);

168 glEnable(GL_TEXTURE_2D);

169

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

171 glActiveTexture(GL_TEXTURE2);

172 glBindTexture(GL_TEXTURE_1D, xfer_tex);

173 glEnable(GL_TEXTURE_1D);

174

175 bind_program(vol_sdr);

176 glBegin(GL_QUADS);

177 glColor3f(1, 1, 1);

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

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

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

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

182 glEnd();

183 bind_program(0);

184

185 glActiveTexture(GL_TEXTURE2);

186 glDisable(GL_TEXTURE_1D);

187 glActiveTexture(GL_TEXTURE1);

188 glDisable(GL_TEXTURE_2D);

189 glActiveTexture(GL_TEXTURE0);

190 glDisable(GL_TEXTURE_3D);

191

192 glMatrixMode(GL_TEXTURE);

193 glPopMatrix();

194 glMatrixMode(GL_MODELVIEW);

195 glPopMatrix();

196 }

197

198 static void draw_slice(void)

199 {

200 glMatrixMode(GL_MODELVIEW);

201 glPushMatrix();

202 glTranslatef(0.9, 0.9, 0);

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

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

205

206 glActiveTexture(GL_TEXTURE0);

207 glBindTexture(GL_TEXTURE_3D, volume->get_texture());

208 glEnable(GL_TEXTURE_3D);

209

210 glActiveTexture(GL_TEXTURE1);

211 glBindTexture(GL_TEXTURE_1D, xfer_tex);

212 glEnable(GL_TEXTURE_1D);

213

214 bind_program(slice_sdr);

215

216 glBegin(GL_QUADS);

217 glColor3f(1, 1, 1);

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

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

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

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

222 glEnd();

223

224 bind_program(0);

225

226 glActiveTexture(GL_TEXTURE1);

227 glDisable(GL_TEXTURE_1D);

228 glActiveTexture(GL_TEXTURE0);

229 glDisable(GL_TEXTURE_3D);

230 glPopMatrix();

231 }

232

233 static void draw_xfer_func(void)

234 {

235 glMatrixMode(GL_MODELVIEW);

236 glPushMatrix();

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

238 glScalef(0.5, 0.1, 1);

239

240 glBindTexture(GL_TEXTURE_1D, xfer_tex);

241 glEnable(GL_TEXTURE_1D);

242

243 glBegin(GL_QUADS);

244 glColor3f(1, 1, 1);

245 glTexCoord1f(1);

246 glVertex2f(1, 0);

247 glVertex2f(1, 1);

248 glTexCoord1f(0);

249 glVertex2f(0, 1);

250 glVertex2f(0, 0);

251 glEnd();

252

253 glDisable(GL_TEXTURE_1D);

254

255 glLineWidth(2.0);

256 glBegin(GL_LINE_LOOP);

257 /*if(uimode == UIMODE_XFER) {

258 glColor3f(1, 0, 0);

259 } else {*/

260 glColor3f(0, 0, 1);

261 //}

262 glVertex2f(0, 0);

263 glVertex2f(1, 0);

264 glVertex2f(1, 1);

265 glVertex2f(0, 1);

266 glEnd();

267

268 glPopMatrix();

269 }

270

271 void volray_resize(int x, int y)

272 {

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

274

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

276 raytex_needs_recalc = true;

277 win_xsz = x;

278 win_ysz = y;

279 }

280 }

281

282 #if 0

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

284 {

285 switch(key) {

286 case 27:

287 exit(0);

288

289 case 'x':

290 uimode = UIMODE_XFER;

291 post_redisplay();

292 break;

293

294 case 'c':

295 uimode = UIMODE_CURSOR;

296 post_redisplay();

297 break;

298

299 default:

300 break;

301 }

302 }

303

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

305 {

306 switch(key) {

307 case 'x':

308 if(uimode == UIMODE_XFER) {

309 uimode = UIMODE_DEFAULT;

310 post_redisplay();

311 }

312 break;

313

314 case 'c':

315 if(uimode == UIMODE_CURSOR) {

316 uimode = UIMODE_DEFAULT;

317 post_redisplay();

318 }

319 break;

320

321 default:

322 break;

323 }

324 }

325 #endif

326

327 static int bnstate[32];

328 static int prev_x, prev_y;

329

330 void volray_mouse(int bn, int state, int x, int y)

331 {

332 bnstate[bn] = state;

333 prev_x = x;

334 prev_y = y;

335 }

336

337 void volray_motion(int x, int y)

338 {

339 int dx = x - prev_x;

340 int dy = y - prev_y;

341 prev_x = x;

342 prev_y = y;

343

344 /*switch(uimode) {

345 case UIMODE_XFER:

346 if(dx || dy) {

347 xfer_mean += dx / (float)win_xsz;

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

349

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

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

352

353 xfertex_needs_recalc = true;

354 post_redisplay();

355 }

356 break;

357

358 case UIMODE_CURSOR:

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

360

361 if(cur_z < 0.0)

362 cur_z = 0.0;

363 if(cur_z > 1.0)

364 cur_z = 1.0;

365

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

367 post_redisplay();

368 break;

369

370 default:*/

371 /* view control */

372 if(bnstate[0]) {

373 cam_theta += dx * 0.5;

374 cam_phi += dy * 0.5;

375

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

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

378 post_redisplay();

379 }

380

381 if(bnstate[1]) {

382 cam_x += dx * 0.025;

383 cam_y += dy * 0.025;

384 post_redisplay();

385 }

386

387 if(bnstate[2]) {

388 cam_dist += dy * 0.025;

389 if(cam_dist < 0.0) cam_dist = 0.0;

390 post_redisplay();

391 }

392 //}

393 }

394

395 #if 0

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

397 {

398 int i;

399 char *endp;

400

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

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

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

404 case 'm':

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

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

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

408 return -1;

409 }

410 break;

411

412 case 'd':

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

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

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

416 return -1;

417 }

418 break;

419

420 default:

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

422 return -1;

423 }

424 } else {

425 if(fname) {

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

427 return -1;

428 }

429 fname = argv[i];

430 }

431 }

432

433 if(!fname) {

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

435 return -1;

436 }

437 return 0;

438 }

439 #endif

440

441

442 static void create_ray_texture(int xsz, int ysz, float vfov, Vector2 *tex_scale)

443 {

444 int cur_tex_xsz, cur_tex_ysz;

445 int tex_xsz = round_pow2(xsz);

446 int tex_ysz = round_pow2(ysz);

447 float *teximg, *dir;

448

449 teximg = new float[3 * xsz * ysz];

450 dir = teximg;

451

452 for(int i=0; i<ysz; i++) {

453 for(int j=0; j<xsz; j++) {

454 Vector3 rdir = get_primary_ray_dir(j, i, xsz, ysz, vfov);

455 *dir++ = rdir.x;

456 *dir++ = rdir.y;

457 *dir++ = rdir.z;

458 }

459 }

460

461 if(!ray_tex) {

462 glGenTextures(1, &ray_tex);

463 }

464

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

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

467

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

469 glBindTexture(GL_TEXTURE_2D, ray_tex);

470 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

471 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

472 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);

473 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);

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

475 }

476

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

478 delete [] teximg;

479

480 if(tex_scale) {

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

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

483 }

484 raytex_needs_recalc = false;

485 }

486

487 static Vector3 get_primary_ray_dir(int x, int y, int w, int h, float vfov_deg)

488 {

489 float vfov = M_PI * vfov_deg / 180.0;

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

491

492 float ysz = 2.0;

493 float xsz = aspect * ysz;

494

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

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

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

498

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

500 return Vector3(px / mag, py / mag, pz / mag);

501 }

502

503 static int round_pow2(int x)

504 {

505 x--;

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

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

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

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

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

511 return x + 1;

512 }

513

514 static void create_transfer_map(float mean, float sdev)

515 {

516 static float map[XFER_MAP_SZ];

517

518 if(!xfer_tex) {

519 glGenTextures(1, &xfer_tex);

520 glBindTexture(GL_TEXTURE_1D, xfer_tex);

521 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

522 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

523 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);

524 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

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

526 }

527

528 for(int i=0; i<XFER_MAP_SZ; i++) {

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

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

531 }

532

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

534 xfertex_needs_recalc = false;

535 }