tavli

annotate src/meshgen.cc @ 11:a8e26f163f99

find changesets by author, revision, files, or words in the commit message
poulia
author John Tsiombikas <nuclear@member.fsf.org>
date Sat, 27 Jun 2015 08:01:51 +0300
parents 3fcd7b4d631f
children ae1c60726c41
rev   line source
nuclear@1 1 #include <stdio.h>
nuclear@1 2 #include "meshgen.h"
nuclear@1 3 #include "mesh.h"
nuclear@1 4
nuclear@1 5 // -------- sphere --------
nuclear@1 6
nuclear@1 7 #define SURAD(u) ((u) * 2.0 * M_PI)
nuclear@1 8 #define SVRAD(v) ((v) * M_PI)
nuclear@1 9
nuclear@1 10 static Vector3 sphvec(float theta, float phi)
nuclear@1 11 {
nuclear@1 12 return Vector3(sin(theta) * sin(phi),
nuclear@1 13 cos(phi),
nuclear@1 14 cos(theta) * sin(phi));
nuclear@1 15 }
nuclear@1 16
nuclear@1 17 void gen_sphere(Mesh *mesh, float rad, int usub, int vsub, float urange, float vrange)
nuclear@1 18 {
nuclear@1 19 if(usub < 4) usub = 4;
nuclear@1 20 if(vsub < 2) vsub = 2;
nuclear@1 21
nuclear@1 22 int uverts = usub + 1;
nuclear@1 23 int vverts = vsub + 1;
nuclear@1 24
nuclear@1 25 int num_verts = uverts * vverts;
nuclear@1 26 int num_quads = usub * vsub;
nuclear@1 27 int num_tri = num_quads * 2;
nuclear@1 28
nuclear@1 29 mesh->clear();
nuclear@1 30 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@1 31 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@1 32 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@1 33 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@1 34 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@1 35
nuclear@1 36 float du = urange / (float)(uverts - 1);
nuclear@1 37 float dv = vrange / (float)(vverts - 1);
nuclear@1 38
nuclear@1 39 float u = 0.0;
nuclear@1 40 for(int i=0; i<uverts; i++) {
nuclear@1 41 float theta = SURAD(u * urange);
nuclear@1 42
nuclear@1 43 float v = 0.0;
nuclear@1 44 for(int j=0; j<vverts; j++) {
nuclear@1 45 float phi = SVRAD(v * vrange);
nuclear@1 46
nuclear@1 47 Vector3 pos = sphvec(theta, phi);
nuclear@1 48
nuclear@1 49 *varr++ = pos * rad;
nuclear@1 50 *narr++ = pos;
nuclear@1 51 *tarr++ = (sphvec(theta + 0.1f, (float)M_PI / 2.0f) - sphvec(theta - 0.1f, (float)M_PI / 2.0f)).normalized();
nuclear@1 52 *uvarr++ = Vector2(u * urange, v * vrange);
nuclear@1 53
nuclear@1 54 if(i < usub && j < vsub) {
nuclear@1 55 int idx = i * vverts + j;
nuclear@1 56 *idxarr++ = idx;
nuclear@1 57 *idxarr++ = idx + 1;
nuclear@1 58 *idxarr++ = idx + vverts + 1;
nuclear@1 59
nuclear@1 60 *idxarr++ = idx;
nuclear@1 61 *idxarr++ = idx + vverts + 1;
nuclear@1 62 *idxarr++ = idx + vverts;
nuclear@1 63 }
nuclear@1 64
nuclear@1 65 v += dv;
nuclear@1 66 }
nuclear@1 67 u += du;
nuclear@1 68 }
nuclear@1 69 }
nuclear@1 70
nuclear@1 71
nuclear@1 72 // -------- cylinder --------
nuclear@1 73
nuclear@1 74 static Vector3 cylvec(float theta, float height)
nuclear@1 75 {
nuclear@1 76 return Vector3(sin(theta), height, cos(theta));
nuclear@1 77 }
nuclear@1 78
nuclear@1 79 void gen_cylinder(Mesh *mesh, float rad, float height, int usub, int vsub, int capsub, float urange, float vrange)
nuclear@1 80 {
nuclear@1 81 if(usub < 4) usub = 4;
nuclear@1 82 if(vsub < 1) vsub = 1;
nuclear@1 83
nuclear@1 84 int uverts = usub + 1;
nuclear@1 85 int vverts = vsub + 1;
nuclear@1 86
nuclear@1 87 int num_body_verts = uverts * vverts;
nuclear@1 88 int num_body_quads = usub * vsub;
nuclear@1 89 int num_body_tri = num_body_quads * 2;
nuclear@1 90
nuclear@1 91 int capvverts = capsub ? capsub + 1 : 0;
nuclear@1 92 int num_cap_verts = uverts * capvverts;
nuclear@1 93 int num_cap_quads = usub * capsub;
nuclear@1 94 int num_cap_tri = num_cap_quads * 2;
nuclear@1 95
nuclear@1 96 int num_verts = num_body_verts + num_cap_verts * 2;
nuclear@1 97 int num_tri = num_body_tri + num_cap_tri * 2;
nuclear@1 98
nuclear@1 99 mesh->clear();
nuclear@1 100 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@1 101 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@1 102 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@1 103 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@1 104 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@1 105
nuclear@1 106 float du = urange / (float)(uverts - 1);
nuclear@1 107 float dv = vrange / (float)(vverts - 1);
nuclear@1 108
nuclear@1 109 float u = 0.0;
nuclear@1 110 for(int i=0; i<uverts; i++) {
nuclear@1 111 float theta = SURAD(u);
nuclear@1 112
nuclear@1 113 float v = 0.0;
nuclear@1 114 for(int j=0; j<vverts; j++) {
nuclear@1 115 float y = (v - 0.5) * height;
nuclear@1 116 Vector3 pos = cylvec(theta, y);
nuclear@1 117
nuclear@1 118 *varr++ = Vector3(pos.x * rad, pos.y, pos.z * rad);
nuclear@1 119 *narr++ = Vector3(pos.x, 0.0, pos.z);
nuclear@1 120 *tarr++ = (cylvec(theta + 0.1, 0.0) - cylvec(theta - 0.1, 0.0)).normalized();
nuclear@1 121 *uvarr++ = Vector2(u * urange, v * vrange);
nuclear@1 122
nuclear@1 123 if(i < usub && j < vsub) {
nuclear@1 124 int idx = i * vverts + j;
nuclear@1 125
nuclear@1 126 *idxarr++ = idx;
nuclear@1 127 *idxarr++ = idx + vverts + 1;
nuclear@1 128 *idxarr++ = idx + 1;
nuclear@1 129
nuclear@1 130 *idxarr++ = idx;
nuclear@1 131 *idxarr++ = idx + vverts;
nuclear@1 132 *idxarr++ = idx + vverts + 1;
nuclear@1 133 }
nuclear@1 134
nuclear@1 135 v += dv;
nuclear@1 136 }
nuclear@1 137 u += du;
nuclear@1 138 }
nuclear@1 139
nuclear@1 140
nuclear@1 141 // now the cap!
nuclear@1 142 if(!capsub) {
nuclear@1 143 return;
nuclear@1 144 }
nuclear@1 145
nuclear@1 146 dv = 1.0 / (float)(capvverts - 1);
nuclear@1 147
nuclear@1 148 u = 0.0;
nuclear@1 149 for(int i=0; i<uverts; i++) {
nuclear@1 150 float theta = SURAD(u);
nuclear@1 151
nuclear@1 152 float v = 0.0;
nuclear@1 153 for(int j=0; j<capvverts; j++) {
nuclear@1 154 float r = v * rad;
nuclear@1 155
nuclear@1 156 Vector3 pos = cylvec(theta, height / 2.0) * r;
nuclear@1 157 pos.y = height / 2.0;
nuclear@1 158 Vector3 tang = (cylvec(theta + 0.1, 0.0) - cylvec(theta - 0.1, 0.0)).normalized();
nuclear@1 159
nuclear@1 160 *varr++ = pos;
nuclear@1 161 *narr++ = Vector3(0, 1, 0);
nuclear@1 162 *tarr++ = tang;
nuclear@1 163 *uvarr++ = Vector2(u * urange, v);
nuclear@1 164
nuclear@1 165 pos.y = -height / 2.0;
nuclear@1 166 *varr++ = pos;
nuclear@1 167 *narr++ = Vector3(0, -1, 0);
nuclear@1 168 *tarr++ = -tang;
nuclear@1 169 *uvarr++ = Vector2(u * urange, v);
nuclear@1 170
nuclear@1 171 if(i < usub && j < capsub) {
nuclear@1 172 unsigned int idx = num_body_verts + (i * capvverts + j) * 2;
nuclear@1 173
nuclear@1 174 unsigned int vidx[4] = {
nuclear@1 175 idx,
nuclear@1 176 idx + capvverts * 2,
nuclear@1 177 idx + (capvverts + 1) * 2,
nuclear@1 178 idx + 2
nuclear@1 179 };
nuclear@1 180
nuclear@1 181 *idxarr++ = vidx[0];
nuclear@1 182 *idxarr++ = vidx[2];
nuclear@1 183 *idxarr++ = vidx[1];
nuclear@1 184 *idxarr++ = vidx[0];
nuclear@1 185 *idxarr++ = vidx[3];
nuclear@1 186 *idxarr++ = vidx[2];
nuclear@1 187
nuclear@1 188 *idxarr++ = vidx[0] + 1;
nuclear@1 189 *idxarr++ = vidx[1] + 1;
nuclear@1 190 *idxarr++ = vidx[2] + 1;
nuclear@1 191 *idxarr++ = vidx[0] + 1;
nuclear@1 192 *idxarr++ = vidx[2] + 1;
nuclear@1 193 *idxarr++ = vidx[3] + 1;
nuclear@1 194 }
nuclear@1 195
nuclear@1 196 v += dv;
nuclear@1 197 }
nuclear@1 198 u += du;
nuclear@1 199 }
nuclear@1 200 }
nuclear@1 201
nuclear@1 202 // -------- cone --------
nuclear@1 203
nuclear@1 204 static Vector3 conevec(float theta, float y, float height)
nuclear@1 205 {
nuclear@1 206 float scale = 1.0 - y / height;
nuclear@1 207 return Vector3(sin(theta) * scale, y, cos(theta) * scale);
nuclear@1 208 }
nuclear@1 209
nuclear@1 210 void gen_cone(Mesh *mesh, float rad, float height, int usub, int vsub, int capsub, float urange, float vrange)
nuclear@1 211 {
nuclear@1 212 if(usub < 4) usub = 4;
nuclear@1 213 if(vsub < 1) vsub = 1;
nuclear@1 214
nuclear@1 215 int uverts = usub + 1;
nuclear@1 216 int vverts = vsub + 1;
nuclear@1 217
nuclear@1 218 int num_body_verts = uverts * vverts;
nuclear@1 219 int num_body_quads = usub * vsub;
nuclear@1 220 int num_body_tri = num_body_quads * 2;
nuclear@1 221
nuclear@1 222 int capvverts = capsub ? capsub + 1 : 0;
nuclear@1 223 int num_cap_verts = uverts * capvverts;
nuclear@1 224 int num_cap_quads = usub * capsub;
nuclear@1 225 int num_cap_tri = num_cap_quads * 2;
nuclear@1 226
nuclear@1 227 int num_verts = num_body_verts + num_cap_verts;
nuclear@1 228 int num_tri = num_body_tri + num_cap_tri;
nuclear@1 229
nuclear@1 230 mesh->clear();
nuclear@1 231 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@1 232 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@1 233 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@1 234 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@1 235 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@1 236
nuclear@1 237 float du = urange / (float)(uverts - 1);
nuclear@1 238 float dv = vrange / (float)(vverts - 1);
nuclear@1 239
nuclear@1 240 float u = 0.0;
nuclear@1 241 for(int i=0; i<uverts; i++) {
nuclear@1 242 float theta = SURAD(u);
nuclear@1 243
nuclear@1 244 float v = 0.0;
nuclear@1 245 for(int j=0; j<vverts; j++) {
nuclear@1 246 float y = v * height;
nuclear@1 247 Vector3 pos = conevec(theta, y, height);
nuclear@1 248
nuclear@1 249 Vector3 tang = (conevec(theta + 0.1, 0.0, height) - conevec(theta - 0.1, 0.0, height)).normalized();
nuclear@1 250 Vector3 bitang = (conevec(theta, y + 0.1, height) - pos).normalized();
nuclear@1 251
nuclear@1 252 *varr++ = Vector3(pos.x * rad, pos.y, pos.z * rad);
nuclear@1 253 *narr++ = cross_product(tang, bitang);
nuclear@1 254 *tarr++ = tang;
nuclear@1 255 *uvarr++ = Vector2(u * urange, v * vrange);
nuclear@1 256
nuclear@1 257 if(i < usub && j < vsub) {
nuclear@1 258 int idx = i * vverts + j;
nuclear@1 259
nuclear@1 260 *idxarr++ = idx;
nuclear@1 261 *idxarr++ = idx + vverts + 1;
nuclear@1 262 *idxarr++ = idx + 1;
nuclear@1 263
nuclear@1 264 *idxarr++ = idx;
nuclear@1 265 *idxarr++ = idx + vverts;
nuclear@1 266 *idxarr++ = idx + vverts + 1;
nuclear@1 267 }
nuclear@1 268
nuclear@1 269 v += dv;
nuclear@1 270 }
nuclear@1 271 u += du;
nuclear@1 272 }
nuclear@1 273
nuclear@1 274
nuclear@1 275 // now the bottom cap!
nuclear@1 276 if(!capsub) {
nuclear@1 277 return;
nuclear@1 278 }
nuclear@1 279
nuclear@1 280 dv = 1.0 / (float)(capvverts - 1);
nuclear@1 281
nuclear@1 282 u = 0.0;
nuclear@1 283 for(int i=0; i<uverts; i++) {
nuclear@1 284 float theta = SURAD(u);
nuclear@1 285
nuclear@1 286 float v = 0.0;
nuclear@1 287 for(int j=0; j<capvverts; j++) {
nuclear@1 288 float r = v * rad;
nuclear@1 289
nuclear@1 290 Vector3 pos = conevec(theta, 0.0, height) * r;
nuclear@1 291 Vector3 tang = (cylvec(theta + 0.1, 0.0) - cylvec(theta - 0.1, 0.0)).normalized();
nuclear@1 292
nuclear@1 293 *varr++ = pos;
nuclear@1 294 *narr++ = Vector3(0, -1, 0);
nuclear@1 295 *tarr++ = tang;
nuclear@1 296 *uvarr++ = Vector2(u * urange, v);
nuclear@1 297
nuclear@1 298 if(i < usub && j < capsub) {
nuclear@1 299 unsigned int idx = num_body_verts + i * capvverts + j;
nuclear@1 300
nuclear@1 301 unsigned int vidx[4] = {
nuclear@1 302 idx,
nuclear@1 303 idx + capvverts,
nuclear@1 304 idx + (capvverts + 1),
nuclear@1 305 idx + 1
nuclear@1 306 };
nuclear@1 307
nuclear@1 308 *idxarr++ = vidx[0];
nuclear@1 309 *idxarr++ = vidx[1];
nuclear@1 310 *idxarr++ = vidx[2];
nuclear@1 311 *idxarr++ = vidx[0];
nuclear@1 312 *idxarr++ = vidx[2];
nuclear@1 313 *idxarr++ = vidx[3];
nuclear@1 314 }
nuclear@1 315
nuclear@1 316 v += dv;
nuclear@1 317 }
nuclear@1 318 u += du;
nuclear@1 319 }
nuclear@1 320 }
nuclear@1 321
nuclear@1 322
nuclear@1 323 // -------- plane --------
nuclear@1 324
nuclear@1 325 void gen_plane(Mesh *mesh, float width, float height, int usub, int vsub)
nuclear@1 326 {
nuclear@1 327 gen_heightmap(mesh, width, height, usub, vsub, 0);
nuclear@1 328 }
nuclear@1 329
nuclear@1 330
nuclear@1 331 // ----- heightmap ------
nuclear@1 332
nuclear@1 333 void gen_heightmap(Mesh *mesh, float width, float height, int usub, int vsub, float (*hf)(float, float, void*), void *hfdata)
nuclear@1 334 {
nuclear@1 335 if(usub < 1) usub = 1;
nuclear@1 336 if(vsub < 1) vsub = 1;
nuclear@1 337
nuclear@1 338 mesh->clear();
nuclear@1 339
nuclear@1 340 int uverts = usub + 1;
nuclear@1 341 int vverts = vsub + 1;
nuclear@1 342 int num_verts = uverts * vverts;
nuclear@1 343
nuclear@1 344 int num_quads = usub * vsub;
nuclear@1 345 int num_tri = num_quads * 2;
nuclear@1 346
nuclear@1 347 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@1 348 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@1 349 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@1 350 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@1 351 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@1 352
nuclear@1 353 float du = 1.0 / (float)usub;
nuclear@1 354 float dv = 1.0 / (float)vsub;
nuclear@1 355
nuclear@1 356 float u = 0.0;
nuclear@1 357 for(int i=0; i<uverts; i++) {
nuclear@1 358 float v = 0.0;
nuclear@1 359 for(int j=0; j<vverts; j++) {
nuclear@1 360 float x = (u - 0.5) * width;
nuclear@1 361 float y = (v - 0.5) * height;
nuclear@1 362 float z = hf ? hf(u, v, hfdata) : 0.0;
nuclear@1 363
nuclear@1 364 Vector3 normal = Vector3(0, 0, 1);
nuclear@1 365 if(hf) {
nuclear@1 366 float u1z = hf(u + du, v, hfdata);
nuclear@1 367 float v1z = hf(u, v + dv, hfdata);
nuclear@1 368
nuclear@1 369 Vector3 tang = Vector3(du * width, 0, u1z - z);
nuclear@1 370 Vector3 bitan = Vector3(0, dv * height, v1z - z);
nuclear@1 371 normal = cross_product(tang, bitan).normalized();
nuclear@1 372 }
nuclear@1 373
nuclear@1 374 *varr++ = Vector3(x, y, z);
nuclear@1 375 *narr++ = normal;
nuclear@1 376 *tarr++ = Vector3(1, 0, 0);
nuclear@1 377 *uvarr++ = Vector2(u, v);
nuclear@1 378
nuclear@1 379 if(i < usub && j < vsub) {
nuclear@1 380 int idx = i * vverts + j;
nuclear@1 381
nuclear@1 382 *idxarr++ = idx;
nuclear@1 383 *idxarr++ = idx + vverts + 1;
nuclear@1 384 *idxarr++ = idx + 1;
nuclear@1 385
nuclear@1 386 *idxarr++ = idx;
nuclear@1 387 *idxarr++ = idx + vverts;
nuclear@1 388 *idxarr++ = idx + vverts + 1;
nuclear@1 389 }
nuclear@1 390
nuclear@1 391 v += dv;
nuclear@1 392 }
nuclear@1 393 u += du;
nuclear@1 394 }
nuclear@1 395 }
nuclear@1 396
nuclear@1 397 // ----- heightmap ------
nuclear@1 398
nuclear@1 399 void gen_box(Mesh *mesh, float xsz, float ysz, float zsz)
nuclear@1 400 {
nuclear@1 401 mesh->clear();
nuclear@1 402
nuclear@1 403 const int num_faces = 6;
nuclear@1 404 int num_verts = num_faces * 4;
nuclear@1 405 int num_tri = num_faces * 2;
nuclear@1 406
nuclear@1 407 float x = xsz / 2.0;
nuclear@1 408 float y = ysz / 2.0;
nuclear@1 409 float z = zsz / 2.0;
nuclear@1 410
nuclear@1 411 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@1 412 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@1 413 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@1 414 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@1 415 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@1 416
nuclear@1 417 static const Vector2 uv[] = { Vector2(0, 0), Vector2(1, 0), Vector2(1, 1), Vector2(0, 1) };
nuclear@1 418
nuclear@1 419 // front
nuclear@1 420 for(int i=0; i<4; i++) {
nuclear@1 421 *narr++ = Vector3(0, 0, 1);
nuclear@1 422 *tarr++ = Vector3(1, 0, 0);
nuclear@1 423 *uvarr++ = uv[i];
nuclear@1 424 }
nuclear@1 425 *varr++ = Vector3(-x, -y, z);
nuclear@1 426 *varr++ = Vector3(x, -y, z);
nuclear@1 427 *varr++ = Vector3(x, y, z);
nuclear@1 428 *varr++ = Vector3(-x, y, z);
nuclear@1 429 // right
nuclear@1 430 for(int i=0; i<4; i++) {
nuclear@1 431 *narr++ = Vector3(1, 0, 0);
nuclear@1 432 *tarr++ = Vector3(0, 0, -1);
nuclear@1 433 *uvarr++ = uv[i];
nuclear@1 434 }
nuclear@1 435 *varr++ = Vector3(x, -y, z);
nuclear@1 436 *varr++ = Vector3(x, -y, -z);
nuclear@1 437 *varr++ = Vector3(x, y, -z);
nuclear@1 438 *varr++ = Vector3(x, y, z);
nuclear@1 439 // back
nuclear@1 440 for(int i=0; i<4; i++) {
nuclear@1 441 *narr++ = Vector3(0, 0, -1);
nuclear@1 442 *tarr++ = Vector3(-1, 0, 0);
nuclear@1 443 *uvarr++ = uv[i];
nuclear@1 444 }
nuclear@1 445 *varr++ = Vector3(x, -y, -z);
nuclear@1 446 *varr++ = Vector3(-x, -y, -z);
nuclear@1 447 *varr++ = Vector3(-x, y, -z);
nuclear@1 448 *varr++ = Vector3(x, y, -z);
nuclear@1 449 // left
nuclear@1 450 for(int i=0; i<4; i++) {
nuclear@1 451 *narr++ = Vector3(-1, 0, 0);
nuclear@1 452 *tarr++ = Vector3(0, 0, 1);
nuclear@1 453 *uvarr++ = uv[i];
nuclear@1 454 }
nuclear@1 455 *varr++ = Vector3(-x, -y, -z);
nuclear@1 456 *varr++ = Vector3(-x, -y, z);
nuclear@1 457 *varr++ = Vector3(-x, y, z);
nuclear@1 458 *varr++ = Vector3(-x, y, -z);
nuclear@1 459 // top
nuclear@1 460 for(int i=0; i<4; i++) {
nuclear@1 461 *narr++ = Vector3(0, 1, 0);
nuclear@1 462 *tarr++ = Vector3(1, 0, 0);
nuclear@1 463 *uvarr++ = uv[i];
nuclear@1 464 }
nuclear@1 465 *varr++ = Vector3(-x, y, z);
nuclear@1 466 *varr++ = Vector3(x, y, z);
nuclear@1 467 *varr++ = Vector3(x, y, -z);
nuclear@1 468 *varr++ = Vector3(-x, y, -z);
nuclear@1 469 // bottom
nuclear@1 470 for(int i=0; i<4; i++) {
nuclear@1 471 *narr++ = Vector3(0, -1, 0);
nuclear@1 472 *tarr++ = Vector3(1, 0, 0);
nuclear@1 473 *uvarr++ = uv[i];
nuclear@1 474 }
nuclear@1 475 *varr++ = Vector3(-x, -y, -z);
nuclear@1 476 *varr++ = Vector3(x, -y, -z);
nuclear@1 477 *varr++ = Vector3(x, -y, z);
nuclear@1 478 *varr++ = Vector3(-x, -y, z);
nuclear@1 479
nuclear@1 480 // index array
nuclear@1 481 static const int faceidx[] = {0, 1, 2, 0, 2, 3};
nuclear@1 482 for(int i=0; i<num_faces; i++) {
nuclear@1 483 for(int j=0; j<6; j++) {
nuclear@1 484 *idxarr++ = faceidx[j] + i * 4;
nuclear@1 485 }
nuclear@1 486 }
nuclear@1 487 }
nuclear@11 488
nuclear@11 489 static inline Vector3 rev_vert(float u, float v, Vector2 (*rf)(float, float, void*), void *cls)
nuclear@11 490 {
nuclear@11 491 Vector2 pos = rf(u, v, cls);
nuclear@11 492
nuclear@11 493 float angle = u * 2.0 * M_PI;
nuclear@11 494 float x = pos.x * cos(angle);
nuclear@11 495 float y = pos.y;
nuclear@11 496 float z = pos.x * sin(angle);
nuclear@11 497
nuclear@11 498 return Vector3(x, y, z);
nuclear@11 499 }
nuclear@11 500
nuclear@11 501 // ------ surface of revolution -------
nuclear@11 502 void gen_revol(Mesh *mesh, int usub, int vsub, Vector2 (*rfunc)(float, float, void*), void *cls)
nuclear@11 503 {
nuclear@11 504 if(!rfunc) return;
nuclear@11 505 if(usub < 3) usub = 3;
nuclear@11 506 if(vsub < 1) vsub = 1;
nuclear@11 507
nuclear@11 508 mesh->clear();
nuclear@11 509
nuclear@11 510 int uverts = usub + 1;
nuclear@11 511 int vverts = vsub + 1;
nuclear@11 512 int num_verts = uverts * vverts;
nuclear@11 513
nuclear@11 514 int num_quads = usub * vsub;
nuclear@11 515 int num_tri = num_quads * 2;
nuclear@11 516
nuclear@11 517 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@11 518 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@11 519 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@11 520 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@11 521 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@11 522
nuclear@11 523 float du = 1.0 / (float)(uverts - 1);
nuclear@11 524 float dv = 1.0 / (float)(vverts - 1);
nuclear@11 525
nuclear@11 526 float u = 0.0;
nuclear@11 527 for(int i=0; i<uverts; i++) {
nuclear@11 528 float v = 0.0;
nuclear@11 529 for(int j=0; j<vverts; j++) {
nuclear@11 530 Vector3 pos = rev_vert(u, v, rfunc, cls);
nuclear@11 531
nuclear@11 532 Vector3 nextu = rev_vert(fmod(u + du, 1.0), v, rfunc, cls);
nuclear@11 533 Vector3 tang = nextu - pos;
nuclear@11 534 if(tang.length_sq() < 1e-6) {
nuclear@11 535 float new_v = v > 0.5 ? v - dv * 0.25 : v + dv * 0.25;
nuclear@11 536 nextu = rev_vert(fmod(u + du, 1.0), new_v, rfunc, cls);
nuclear@11 537 tang = nextu - pos;
nuclear@11 538 }
nuclear@11 539
nuclear@11 540 Vector3 nextv = rev_vert(u, v + dv, rfunc, cls);
nuclear@11 541 Vector3 bitan = nextv - pos;
nuclear@11 542 if(bitan.length_sq() < 1e-6) {
nuclear@11 543 nextv = rev_vert(u, v - dv, rfunc, cls);
nuclear@11 544 bitan = pos - nextv;
nuclear@11 545 }
nuclear@11 546
nuclear@11 547 Vector3 normal = cross_product(tang, bitan);
nuclear@11 548
nuclear@11 549 *varr++ = pos;
nuclear@11 550 *narr++ = normal.normalized();
nuclear@11 551 *tarr++ = tang.normalized();
nuclear@11 552 *uvarr++ = Vector2(u, v);
nuclear@11 553
nuclear@11 554 if(i < usub && j < vsub) {
nuclear@11 555 int idx = i * vverts + j;
nuclear@11 556
nuclear@11 557 *idxarr++ = idx;
nuclear@11 558 *idxarr++ = idx + vverts + 1;
nuclear@11 559 *idxarr++ = idx + 1;
nuclear@11 560
nuclear@11 561 *idxarr++ = idx;
nuclear@11 562 *idxarr++ = idx + vverts;
nuclear@11 563 *idxarr++ = idx + vverts + 1;
nuclear@11 564 }
nuclear@11 565
nuclear@11 566 v += dv;
nuclear@11 567 }
nuclear@11 568 u += du;
nuclear@11 569 }
nuclear@11 570 }