qvolray

annotate src/volray.cc @ 22:2d0dfb5751dc

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foo
author John Tsiombikas <nuclear@member.fsf.org>
date Wed, 11 Apr 2012 18:35:12 +0300
parents 4c62be57fc1a
children 53aca4775514
rev   line source
nuclear@0 1 #include <stdio.h>
nuclear@0 2 #include <stdlib.h>
nuclear@0 3 #include <assert.h>
nuclear@0 4
nuclear@0 5 #include <GL/glew.h>
nuclear@0 6 #ifndef __APPLE__
nuclear@0 7 #include <GL/glut.h>
nuclear@0 8 #else
nuclear@0 9 #include <GLUT/glut.h>
nuclear@0 10 #endif
nuclear@0 11
nuclear@0 12 #include <vmath/vmath.h>
nuclear@0 13 #include <imago2.h>
nuclear@0 14 #include "sdr.h"
nuclear@9 15 #include "volume.h"
nuclear@13 16 #include "ui.h"
nuclear@18 17 #include "demo.h"
nuclear@0 18
nuclear@3 19 #define XFER_MAP_SZ 512
nuclear@3 20
nuclear@11 21 static void render_volume();
nuclear@11 22 static void draw_slice();
nuclear@11 23 static void draw_xfer_func();
nuclear@5 24
nuclear@11 25 /*
nuclear@0 26 void keyb(unsigned char key, int x, int y);
nuclear@4 27 void keyb_up(unsigned char key, int x, int y);
nuclear@0 28 void mouse(int bn, int state, int x, int y);
nuclear@0 29 void motion(int x, int y);
nuclear@0 30 int parse_args(int argc, char **argv);
nuclear@11 31 */
nuclear@0 32
nuclear@11 33 static void create_ray_texture(int xsz, int ysz, float vfov, Vector2 *tex_scale);
nuclear@11 34 static Vector3 get_primary_ray_dir(int x, int y, int w, int h, float vfov_deg);
nuclear@0 35 static int round_pow2(int x);
nuclear@3 36 static void create_transfer_map(float mean, float sdev);
nuclear@0 37
nuclear@9 38 static float cam_theta = 0, cam_phi = 0, cam_dist = 4.0;
nuclear@9 39 static float cam_x, cam_y, cam_z;
nuclear@0 40
nuclear@13 41 static Vector2 tex_scale;
nuclear@9 42 static unsigned int vol_sdr, slice_sdr, ray_tex;
nuclear@9 43 static int win_xsz, win_ysz;
nuclear@11 44 static bool raytex_needs_recalc = true;
nuclear@0 45
nuclear@9 46 static unsigned int xfer_tex;
nuclear@9 47 static float xfer_mean = 0.7, xfer_sdev = 0.1;
nuclear@11 48 static bool xfertex_needs_recalc = true;
nuclear@3 49
nuclear@19 50 static float cur_z = 0.5;
nuclear@7 51 static float ray_step = 0.01;
nuclear@4 52
nuclear@18 53 static Volume *volume;
nuclear@9 54
nuclear@9 55
nuclear@11 56 bool volray_init()
nuclear@0 57 {
nuclear@0 58 glewInit();
nuclear@0 59
nuclear@9 60 if(!(vol_sdr = create_program_load("sdr/volray.v.glsl", "sdr/volray.p.glsl"))) {
nuclear@11 61 return false;
nuclear@0 62 }
nuclear@5 63 set_uniform_int(vol_sdr, "volume", 0);
nuclear@5 64 set_uniform_int(vol_sdr, "ray_tex", 1);
nuclear@5 65 set_uniform_int(vol_sdr, "xfer_tex", 2);
nuclear@7 66 set_uniform_float(vol_sdr, "ray_step", ray_step);
nuclear@7 67 set_uniform_float(vol_sdr, "zclip", cur_z);
nuclear@5 68
nuclear@9 69 if(!(slice_sdr = create_program_load(0, "sdr/slice.p.glsl"))) {
nuclear@11 70 return false;
nuclear@5 71 }
nuclear@5 72 set_uniform_int(slice_sdr, "volume", 0);
nuclear@5 73 set_uniform_int(slice_sdr, "xfer_tex", 1);
nuclear@0 74
nuclear@18 75 init_demo();
nuclear@18 76
nuclear@11 77 return true;
nuclear@0 78 }
nuclear@0 79
nuclear@18 80 void volray_setvolume(Volume *vol)
nuclear@13 81 {
nuclear@13 82 volume = vol;
nuclear@13 83 }
nuclear@13 84
nuclear@18 85 Volume *volray_getvolume()
nuclear@18 86 {
nuclear@18 87 return volume;
nuclear@18 88 }
nuclear@18 89
nuclear@21 90 void volray_setvalue(int which, float val)
nuclear@21 91 {
nuclear@21 92 switch(which) {
nuclear@21 93 case VOLRAY_ZCURSOR:
nuclear@21 94 cur_z = val;
nuclear@21 95 set_uniform_float(vol_sdr, "zclip", cur_z);
nuclear@21 96 post_redisplay();
nuclear@21 97 break;
nuclear@21 98
nuclear@22 99 case VOLRAY_ZCLIP:
nuclear@22 100
nuclear@21 101 default:
nuclear@21 102 break;
nuclear@21 103 }
nuclear@21 104 }
nuclear@21 105
nuclear@21 106 float volray_getvalue(int which)
nuclear@21 107 {
nuclear@21 108 switch(which) {
nuclear@21 109 case VOLRAY_ZCURSOR:
nuclear@21 110 return cur_z;
nuclear@21 111
nuclear@21 112 default:
nuclear@21 113 break;
nuclear@21 114 }
nuclear@21 115 return 0.0;
nuclear@21 116 }
nuclear@21 117
nuclear@11 118 void volray_draw(void)
nuclear@0 119 {
nuclear@4 120 /* recalculate primary ray texture if needed */
nuclear@1 121 if(raytex_needs_recalc) {
nuclear@1 122 create_ray_texture(win_xsz, win_ysz, 50.0, &tex_scale);
nuclear@1 123 }
nuclear@4 124 /* recalculate transfer function texture if needed */
nuclear@3 125 if(xfertex_needs_recalc) {
nuclear@3 126 create_transfer_map(xfer_mean, xfer_sdev);
nuclear@3 127 }
nuclear@1 128
nuclear@18 129 draw_demo();
nuclear@18 130
nuclear@13 131 glClear(GL_COLOR_BUFFER_BIT);
nuclear@13 132
nuclear@13 133 if(volume) {
nuclear@13 134 render_volume();
nuclear@13 135 draw_slice();
nuclear@13 136 draw_xfer_func();
nuclear@13 137 }
nuclear@4 138
nuclear@4 139 assert(glGetError() == GL_NO_ERROR);
nuclear@4 140 }
nuclear@4 141
nuclear@11 142 static void render_volume(void)
nuclear@4 143 {
nuclear@4 144 /* set the camera transformation */
nuclear@0 145 glMatrixMode(GL_MODELVIEW);
nuclear@4 146 glPushMatrix();
nuclear@0 147 glLoadIdentity();
nuclear@1 148 glRotatef(-90, 1, 0, 0);
nuclear@0 149 glTranslatef(cam_x, cam_y, -cam_z);
nuclear@0 150 glRotatef(cam_theta, 0, 1, 0);
nuclear@0 151 glRotatef(cam_phi, 1, 0, 0);
nuclear@0 152 glTranslatef(0, 0, -cam_dist);
nuclear@0 153
nuclear@4 154 /* setup the texture matrix to map the useful part of the ray texture to [0,1] */
nuclear@0 155 glMatrixMode(GL_TEXTURE);
nuclear@4 156 glPushMatrix();
nuclear@1 157 glLoadIdentity();
nuclear@0 158 glScalef(tex_scale.x, tex_scale.y, 1.0);
nuclear@0 159
nuclear@4 160 /* tex unit0: volume data 3D texture */
nuclear@0 161 glActiveTexture(GL_TEXTURE0);
nuclear@13 162 glBindTexture(GL_TEXTURE_3D, volume->get_texture());
nuclear@0 163 glEnable(GL_TEXTURE_3D);
nuclear@0 164
nuclear@4 165 /* tex unit1: primary rays in view space */
nuclear@0 166 glActiveTexture(GL_TEXTURE1);
nuclear@1 167 glBindTexture(GL_TEXTURE_2D, ray_tex);
nuclear@0 168 glEnable(GL_TEXTURE_2D);
nuclear@0 169
nuclear@4 170 /* tex unit2: transfer function (1d) */
nuclear@3 171 glActiveTexture(GL_TEXTURE2);
nuclear@3 172 glBindTexture(GL_TEXTURE_1D, xfer_tex);
nuclear@3 173 glEnable(GL_TEXTURE_1D);
nuclear@3 174
nuclear@5 175 bind_program(vol_sdr);
nuclear@0 176 glBegin(GL_QUADS);
nuclear@0 177 glColor3f(1, 1, 1);
nuclear@1 178 glTexCoord2f(0, 1); glVertex2f(-1, -1);
nuclear@1 179 glTexCoord2f(1, 1); glVertex2f(1, -1);
nuclear@1 180 glTexCoord2f(1, 0); glVertex2f(1, 1);
nuclear@1 181 glTexCoord2f(0, 0); glVertex2f(-1, 1);
nuclear@0 182 glEnd();
nuclear@0 183 bind_program(0);
nuclear@0 184
nuclear@3 185 glActiveTexture(GL_TEXTURE2);
nuclear@3 186 glDisable(GL_TEXTURE_1D);
nuclear@1 187 glActiveTexture(GL_TEXTURE1);
nuclear@0 188 glDisable(GL_TEXTURE_2D);
nuclear@0 189 glActiveTexture(GL_TEXTURE0);
nuclear@0 190 glDisable(GL_TEXTURE_3D);
nuclear@0 191
nuclear@0 192 glMatrixMode(GL_TEXTURE);
nuclear@4 193 glPopMatrix();
nuclear@4 194 glMatrixMode(GL_MODELVIEW);
nuclear@4 195 glPopMatrix();
nuclear@4 196 }
nuclear@0 197
nuclear@11 198 static void draw_slice(void)
nuclear@5 199 {
nuclear@5 200 glMatrixMode(GL_MODELVIEW);
nuclear@5 201 glPushMatrix();
nuclear@5 202 glTranslatef(0.9, 0.9, 0);
nuclear@5 203 glScalef(0.3, 0.3 * ((float)win_xsz / win_ysz), 1);
nuclear@5 204 glTranslatef(-1, -1, 0);
nuclear@5 205
nuclear@5 206 glActiveTexture(GL_TEXTURE0);
nuclear@13 207 glBindTexture(GL_TEXTURE_3D, volume->get_texture());
nuclear@5 208 glEnable(GL_TEXTURE_3D);
nuclear@5 209
nuclear@5 210 glActiveTexture(GL_TEXTURE1);
nuclear@5 211 glBindTexture(GL_TEXTURE_1D, xfer_tex);
nuclear@5 212 glEnable(GL_TEXTURE_1D);
nuclear@5 213
nuclear@5 214 bind_program(slice_sdr);
nuclear@5 215
nuclear@5 216 glBegin(GL_QUADS);
nuclear@5 217 glColor3f(1, 1, 1);
nuclear@5 218 glTexCoord3f(0, 1, cur_z); glVertex2f(-1, -1);
nuclear@5 219 glTexCoord3f(1, 1, cur_z); glVertex2f(1, -1);
nuclear@5 220 glTexCoord3f(1, 0, cur_z); glVertex2f(1, 1);
nuclear@5 221 glTexCoord3f(0, 0, cur_z); glVertex2f(-1, 1);
nuclear@5 222 glEnd();
nuclear@5 223
nuclear@5 224 bind_program(0);
nuclear@5 225
nuclear@5 226 glActiveTexture(GL_TEXTURE1);
nuclear@5 227 glDisable(GL_TEXTURE_1D);
nuclear@5 228 glActiveTexture(GL_TEXTURE0);
nuclear@5 229 glDisable(GL_TEXTURE_3D);
nuclear@5 230 glPopMatrix();
nuclear@5 231 }
nuclear@5 232
nuclear@11 233 static void draw_xfer_func(void)
nuclear@4 234 {
nuclear@4 235 glMatrixMode(GL_MODELVIEW);
nuclear@4 236 glPushMatrix();
nuclear@4 237 glTranslatef(-0.9, -0.9, 0);
nuclear@4 238 glScalef(0.5, 0.1, 1);
nuclear@4 239
nuclear@4 240 glBindTexture(GL_TEXTURE_1D, xfer_tex);
nuclear@4 241 glEnable(GL_TEXTURE_1D);
nuclear@4 242
nuclear@4 243 glBegin(GL_QUADS);
nuclear@4 244 glColor3f(1, 1, 1);
nuclear@4 245 glTexCoord1f(1);
nuclear@4 246 glVertex2f(1, 0);
nuclear@4 247 glVertex2f(1, 1);
nuclear@4 248 glTexCoord1f(0);
nuclear@4 249 glVertex2f(0, 1);
nuclear@4 250 glVertex2f(0, 0);
nuclear@4 251 glEnd();
nuclear@4 252
nuclear@4 253 glDisable(GL_TEXTURE_1D);
nuclear@4 254
nuclear@4 255 glLineWidth(2.0);
nuclear@4 256 glBegin(GL_LINE_LOOP);
nuclear@13 257 /*if(uimode == UIMODE_XFER) {
nuclear@5 258 glColor3f(1, 0, 0);
nuclear@13 259 } else {*/
nuclear@5 260 glColor3f(0, 0, 1);
nuclear@13 261 //}
nuclear@4 262 glVertex2f(0, 0);
nuclear@4 263 glVertex2f(1, 0);
nuclear@4 264 glVertex2f(1, 1);
nuclear@4 265 glVertex2f(0, 1);
nuclear@4 266 glEnd();
nuclear@4 267
nuclear@4 268 glPopMatrix();
nuclear@0 269 }
nuclear@0 270
nuclear@11 271 void volray_resize(int x, int y)
nuclear@0 272 {
nuclear@0 273 glViewport(0, 0, x, y);
nuclear@0 274
nuclear@0 275 if(x != win_xsz || y != win_ysz) {
nuclear@11 276 raytex_needs_recalc = true;
nuclear@0 277 win_xsz = x;
nuclear@0 278 win_ysz = y;
nuclear@0 279 }
nuclear@0 280 }
nuclear@0 281
nuclear@11 282 #if 0
nuclear@0 283 void keyb(unsigned char key, int x, int y)
nuclear@0 284 {
nuclear@0 285 switch(key) {
nuclear@0 286 case 27:
nuclear@0 287 exit(0);
nuclear@4 288
nuclear@4 289 case 'x':
nuclear@5 290 uimode = UIMODE_XFER;
nuclear@13 291 post_redisplay();
nuclear@4 292 break;
nuclear@5 293
nuclear@5 294 case 'c':
nuclear@5 295 uimode = UIMODE_CURSOR;
nuclear@13 296 post_redisplay();
nuclear@5 297 break;
nuclear@5 298
nuclear@5 299 default:
nuclear@5 300 break;
nuclear@4 301 }
nuclear@4 302 }
nuclear@4 303
nuclear@4 304 void keyb_up(unsigned char key, int x, int y)
nuclear@4 305 {
nuclear@4 306 switch(key) {
nuclear@4 307 case 'x':
nuclear@5 308 if(uimode == UIMODE_XFER) {
nuclear@5 309 uimode = UIMODE_DEFAULT;
nuclear@13 310 post_redisplay();
nuclear@5 311 }
nuclear@5 312 break;
nuclear@5 313
nuclear@5 314 case 'c':
nuclear@5 315 if(uimode == UIMODE_CURSOR) {
nuclear@5 316 uimode = UIMODE_DEFAULT;
nuclear@13 317 post_redisplay();
nuclear@5 318 }
nuclear@5 319 break;
nuclear@5 320
nuclear@5 321 default:
nuclear@4 322 break;
nuclear@0 323 }
nuclear@0 324 }
nuclear@13 325 #endif
nuclear@0 326
nuclear@0 327 static int bnstate[32];
nuclear@0 328 static int prev_x, prev_y;
nuclear@0 329
nuclear@13 330 void volray_mouse(int bn, int state, int x, int y)
nuclear@0 331 {
nuclear@13 332 bnstate[bn] = state;
nuclear@0 333 prev_x = x;
nuclear@0 334 prev_y = y;
nuclear@0 335 }
nuclear@0 336
nuclear@13 337 void volray_motion(int x, int y)
nuclear@0 338 {
nuclear@0 339 int dx = x - prev_x;
nuclear@0 340 int dy = y - prev_y;
nuclear@0 341 prev_x = x;
nuclear@0 342 prev_y = y;
nuclear@0 343
nuclear@13 344 /*switch(uimode) {
nuclear@5 345 case UIMODE_XFER:
nuclear@4 346 if(dx || dy) {
nuclear@4 347 xfer_mean += dx / (float)win_xsz;
nuclear@4 348 xfer_sdev += 0.5 * dy / (float)win_ysz;
nuclear@0 349
nuclear@4 350 xfer_mean = xfer_mean < 0.0 ? 0.0 : (xfer_mean > 1.0 ? 1.0 : xfer_mean);
nuclear@4 351 xfer_sdev = xfer_sdev < 0.0 ? 0.0 : (xfer_sdev > 1.0 ? 1.0 : xfer_sdev);
nuclear@0 352
nuclear@11 353 xfertex_needs_recalc = true;
nuclear@13 354 post_redisplay();
nuclear@4 355 }
nuclear@5 356 break;
nuclear@0 357
nuclear@5 358 case UIMODE_CURSOR:
nuclear@5 359 cur_z += 0.5 * dy / (float)win_ysz;
nuclear@5 360
nuclear@5 361 if(cur_z < 0.0)
nuclear@5 362 cur_z = 0.0;
nuclear@5 363 if(cur_z > 1.0)
nuclear@5 364 cur_z = 1.0;
nuclear@7 365
nuclear@7 366 set_uniform_float(vol_sdr, "zclip", cur_z);
nuclear@13 367 post_redisplay();
nuclear@5 368 break;
nuclear@5 369
nuclear@13 370 default:*/
nuclear@5 371 /* view control */
nuclear@4 372 if(bnstate[0]) {
nuclear@4 373 cam_theta += dx * 0.5;
nuclear@4 374 cam_phi += dy * 0.5;
nuclear@0 375
nuclear@4 376 if(cam_phi <= -90) cam_phi = -89;
nuclear@4 377 if(cam_phi >= 90) cam_phi = 89;
nuclear@13 378 post_redisplay();
nuclear@4 379 }
nuclear@4 380
nuclear@4 381 if(bnstate[1]) {
nuclear@4 382 cam_x += dx * 0.025;
nuclear@4 383 cam_y += dy * 0.025;
nuclear@13 384 post_redisplay();
nuclear@4 385 }
nuclear@4 386
nuclear@4 387 if(bnstate[2]) {
nuclear@4 388 cam_dist += dy * 0.025;
nuclear@4 389 if(cam_dist < 0.0) cam_dist = 0.0;
nuclear@13 390 post_redisplay();
nuclear@4 391 }
nuclear@13 392 //}
nuclear@0 393 }
nuclear@0 394
nuclear@13 395 #if 0
nuclear@0 396 int parse_args(int argc, char **argv)
nuclear@0 397 {
nuclear@0 398 int i;
nuclear@3 399 char *endp;
nuclear@0 400
nuclear@0 401 for(i=1; i<argc; i++) {
nuclear@2 402 if(argv[i][0] == '-' && argv[i][2] == 0) {
nuclear@2 403 switch(argv[i][1]) {
nuclear@3 404 case 'm':
nuclear@3 405 xfer_mean = strtod(argv[++i], &endp);
nuclear@3 406 if(endp == argv[i]) {
nuclear@3 407 fprintf(stderr, "-m must be followed by the transfer function mean\n");
nuclear@3 408 return -1;
nuclear@3 409 }
nuclear@2 410 break;
nuclear@3 411
nuclear@4 412 case 'd':
nuclear@3 413 xfer_sdev = strtod(argv[++i], &endp);
nuclear@3 414 if(endp == argv[i]) {
nuclear@4 415 fprintf(stderr, "-d must be followed by the transfer function std.deviation\n");
nuclear@3 416 return -1;
nuclear@3 417 }
nuclear@3 418 break;
nuclear@3 419
nuclear@3 420 default:
nuclear@3 421 fprintf(stderr, "unrecognized option: %s\n", argv[i]);
nuclear@3 422 return -1;
nuclear@2 423 }
nuclear@2 424 } else {
nuclear@9 425 if(fname) {
nuclear@9 426 fprintf(stderr, "unexpected argument: %s\n", argv[i]);
nuclear@2 427 return -1;
nuclear@2 428 }
nuclear@9 429 fname = argv[i];
nuclear@0 430 }
nuclear@0 431 }
nuclear@0 432
nuclear@9 433 if(!fname) {
nuclear@9 434 fprintf(stderr, "pass the volume descriptor filename\n");
nuclear@0 435 return -1;
nuclear@0 436 }
nuclear@0 437 return 0;
nuclear@0 438 }
nuclear@11 439 #endif
nuclear@0 440
nuclear@0 441
nuclear@11 442 static void create_ray_texture(int xsz, int ysz, float vfov, Vector2 *tex_scale)
nuclear@0 443 {
nuclear@1 444 int cur_tex_xsz, cur_tex_ysz;
nuclear@0 445 int tex_xsz = round_pow2(xsz);
nuclear@0 446 int tex_ysz = round_pow2(ysz);
nuclear@0 447 float *teximg, *dir;
nuclear@0 448
nuclear@11 449 teximg = new float[3 * xsz * ysz];
nuclear@0 450 dir = teximg;
nuclear@0 451
nuclear@11 452 for(int i=0; i<ysz; i++) {
nuclear@11 453 for(int j=0; j<xsz; j++) {
nuclear@11 454 Vector3 rdir = get_primary_ray_dir(j, i, xsz, ysz, vfov);
nuclear@1 455 *dir++ = rdir.x;
nuclear@1 456 *dir++ = rdir.y;
nuclear@1 457 *dir++ = rdir.z;
nuclear@0 458 }
nuclear@0 459 }
nuclear@0 460
nuclear@1 461 if(!ray_tex) {
nuclear@1 462 glGenTextures(1, &ray_tex);
nuclear@1 463 }
nuclear@1 464
nuclear@1 465 glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_WIDTH, &cur_tex_xsz);
nuclear@1 466 glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_HEIGHT, &cur_tex_ysz);
nuclear@1 467
nuclear@1 468 if(tex_xsz > cur_tex_xsz || tex_ysz > cur_tex_ysz) {
nuclear@1 469 glBindTexture(GL_TEXTURE_2D, ray_tex);
nuclear@1 470 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
nuclear@1 471 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
nuclear@1 472 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
nuclear@1 473 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
nuclear@1 474 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB32F_ARB, tex_xsz, tex_ysz, 0, GL_RGB, GL_FLOAT, 0);
nuclear@1 475 }
nuclear@1 476
nuclear@1 477 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, xsz, ysz, GL_RGB, GL_FLOAT, teximg);
nuclear@11 478 delete [] teximg;
nuclear@0 479
nuclear@0 480 if(tex_scale) {
nuclear@0 481 tex_scale->x = (float)xsz / (float)tex_xsz;
nuclear@0 482 tex_scale->y = (float)ysz / (float)tex_ysz;
nuclear@0 483 }
nuclear@11 484 raytex_needs_recalc = false;
nuclear@0 485 }
nuclear@0 486
nuclear@11 487 static Vector3 get_primary_ray_dir(int x, int y, int w, int h, float vfov_deg)
nuclear@0 488 {
nuclear@0 489 float vfov = M_PI * vfov_deg / 180.0;
nuclear@0 490 float aspect = (float)w / (float)h;
nuclear@0 491
nuclear@0 492 float ysz = 2.0;
nuclear@0 493 float xsz = aspect * ysz;
nuclear@0 494
nuclear@0 495 float px = ((float)x / (float)w) * xsz - xsz / 2.0;
nuclear@0 496 float py = 1.0 - ((float)y / (float)h) * ysz;
nuclear@0 497 float pz = 1.0 / tan(0.5 * vfov);
nuclear@0 498
nuclear@0 499 float mag = sqrt(px * px + py * py + pz * pz);
nuclear@11 500 return Vector3(px / mag, py / mag, pz / mag);
nuclear@0 501 }
nuclear@0 502
nuclear@0 503 static int round_pow2(int x)
nuclear@0 504 {
nuclear@0 505 x--;
nuclear@0 506 x = (x >> 1) | x;
nuclear@0 507 x = (x >> 2) | x;
nuclear@0 508 x = (x >> 4) | x;
nuclear@0 509 x = (x >> 8) | x;
nuclear@0 510 x = (x >> 16) | x;
nuclear@0 511 return x + 1;
nuclear@0 512 }
nuclear@0 513
nuclear@3 514 static void create_transfer_map(float mean, float sdev)
nuclear@3 515 {
nuclear@3 516 static float map[XFER_MAP_SZ];
nuclear@3 517
nuclear@3 518 if(!xfer_tex) {
nuclear@3 519 glGenTextures(1, &xfer_tex);
nuclear@3 520 glBindTexture(GL_TEXTURE_1D, xfer_tex);
nuclear@3 521 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
nuclear@3 522 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
nuclear@3 523 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
nuclear@3 524 glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
nuclear@3 525 glTexImage1D(GL_TEXTURE_1D, 0, GL_LUMINANCE32F_ARB, XFER_MAP_SZ, 0, GL_LUMINANCE, GL_FLOAT, 0);
nuclear@3 526 }
nuclear@3 527
nuclear@11 528 for(int i=0; i<XFER_MAP_SZ; i++) {
nuclear@4 529 float x = (float)i / (float)(XFER_MAP_SZ - 1);
nuclear@4 530 map[i] = gaussian(x, mean, sdev) - 1.0;
nuclear@3 531 }
nuclear@3 532
nuclear@4 533 glTexSubImage1D(GL_TEXTURE_1D, 0, 0, XFER_MAP_SZ, GL_LUMINANCE, GL_FLOAT, map);
nuclear@11 534 xfertex_needs_recalc = false;
nuclear@3 535 }