goat3dgfx

annotate src/meshgen.cc @ 13:25bf39105c82

find changesets by author, revision, files, or words in the commit message
lalal
author John Tsiombikas <nuclear@member.fsf.org>
date Wed, 27 Nov 2013 08:08:59 +0200
parents
children 7d6b667821cf
rev   line source
nuclear@0 1 #include "meshgen.h"
nuclear@0 2 #include "mesh.h"
nuclear@0 3 #include "logger.h"
nuclear@0 4
nuclear@0 5 // -------- sphere --------
nuclear@0 6
nuclear@0 7 #define SURAD(u) ((u) * 2.0 * M_PI)
nuclear@0 8 #define SVRAD(v) ((v) * M_PI)
nuclear@0 9
nuclear@0 10 static Vector3 sphvec(float theta, float phi)
nuclear@0 11 {
nuclear@0 12 return Vector3(sin(theta) * sin(phi),
nuclear@0 13 cos(phi),
nuclear@0 14 cos(theta) * sin(phi));
nuclear@0 15 }
nuclear@0 16
nuclear@0 17 void gen_sphere(Mesh *mesh, float rad, int usub, int vsub, float urange, float vrange)
nuclear@0 18 {
nuclear@0 19 if(usub < 4) usub = 4;
nuclear@0 20 if(vsub < 2) vsub = 2;
nuclear@0 21
nuclear@0 22 int uverts = usub + 1;
nuclear@0 23 int vverts = vsub + 1;
nuclear@0 24
nuclear@0 25 int num_verts = uverts * vverts;
nuclear@0 26 int num_quads = usub * vsub;
nuclear@0 27 int num_tri = num_quads * 2;
nuclear@0 28
nuclear@0 29 mesh->clear();
nuclear@0 30 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@0 31 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@0 32 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@0 33 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@0 34 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@0 35
nuclear@0 36 float du = urange / (float)(uverts - 1);
nuclear@0 37 float dv = vrange / (float)(vverts - 1);
nuclear@0 38
nuclear@0 39 float u = 0.0;
nuclear@0 40 for(int i=0; i<uverts; i++) {
nuclear@0 41 float theta = SURAD(u * urange);
nuclear@0 42
nuclear@0 43 float v = 0.0;
nuclear@0 44 for(int j=0; j<vverts; j++) {
nuclear@0 45 float phi = SVRAD(v * vrange);
nuclear@0 46
nuclear@0 47 Vector3 pos = sphvec(theta, phi);
nuclear@0 48
nuclear@0 49 *varr++ = pos * rad;
nuclear@0 50 *narr++ = pos;
nuclear@0 51 *tarr++ = (sphvec(theta + 0.1, M_PI / 2.0) - sphvec(theta - 0.1, M_PI / 2.0)).normalized();
nuclear@0 52 *uvarr++ = Vector2(u * urange, v * vrange);
nuclear@0 53
nuclear@0 54 if(i < usub && j < vsub) {
nuclear@0 55 int idx = i * vverts + j;
nuclear@0 56 *idxarr++ = idx;
nuclear@0 57 *idxarr++ = idx + 1;
nuclear@0 58 *idxarr++ = idx + vverts + 1;
nuclear@0 59
nuclear@0 60 *idxarr++ = idx;
nuclear@0 61 *idxarr++ = idx + vverts + 1;
nuclear@0 62 *idxarr++ = idx + vverts;
nuclear@0 63 }
nuclear@0 64
nuclear@0 65 v += dv;
nuclear@0 66 }
nuclear@0 67 u += du;
nuclear@0 68 }
nuclear@0 69 }
nuclear@0 70
nuclear@0 71
nuclear@0 72 // -------- cylinder --------
nuclear@0 73
nuclear@0 74 static Vector3 cylvec(float theta, float height)
nuclear@0 75 {
nuclear@0 76 return Vector3(sin(theta), height, cos(theta));
nuclear@0 77 }
nuclear@0 78
nuclear@0 79 void gen_cylinder(Mesh *mesh, float rad, float height, int usub, int vsub, int capsub, float urange, float vrange)
nuclear@0 80 {
nuclear@0 81 if(usub < 4) usub = 4;
nuclear@0 82 if(vsub < 1) vsub = 1;
nuclear@0 83
nuclear@0 84 int uverts = usub + 1;
nuclear@0 85 int vverts = vsub + 1;
nuclear@0 86
nuclear@0 87 int num_body_verts = uverts * vverts;
nuclear@0 88 int num_body_quads = usub * vsub;
nuclear@0 89 int num_body_tri = num_body_quads * 2;
nuclear@0 90
nuclear@0 91 int capvverts = capsub ? capsub + 1 : 0;
nuclear@0 92 int num_cap_verts = uverts * capvverts;
nuclear@0 93 int num_cap_quads = usub * capsub;
nuclear@0 94 int num_cap_tri = num_cap_quads * 2;
nuclear@0 95
nuclear@0 96 int num_verts = num_body_verts + num_cap_verts * 2;
nuclear@0 97 int num_tri = num_body_tri + num_cap_tri * 2;
nuclear@0 98
nuclear@0 99 mesh->clear();
nuclear@0 100 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@0 101 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@0 102 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@0 103 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@0 104 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@0 105
nuclear@0 106 float du = urange / (float)(uverts - 1);
nuclear@0 107 float dv = vrange / (float)(vverts - 1);
nuclear@0 108
nuclear@0 109 float u = 0.0;
nuclear@0 110 for(int i=0; i<uverts; i++) {
nuclear@0 111 float theta = SURAD(u);
nuclear@0 112
nuclear@0 113 float v = 0.0;
nuclear@0 114 for(int j=0; j<vverts; j++) {
nuclear@0 115 float y = (v - 0.5) * height;
nuclear@0 116 Vector3 pos = cylvec(theta, y);
nuclear@0 117
nuclear@0 118 *varr++ = Vector3(pos.x * rad, pos.y, pos.z * rad);
nuclear@0 119 *narr++ = Vector3(pos.x, 0.0, pos.z);
nuclear@0 120 *tarr++ = (cylvec(theta + 0.1, 0.0) - cylvec(theta - 0.1, 0.0)).normalized();
nuclear@0 121 *uvarr++ = Vector2(u * urange, v * vrange);
nuclear@0 122
nuclear@0 123 if(i < usub && j < vsub) {
nuclear@0 124 int idx = i * vverts + j;
nuclear@0 125
nuclear@0 126 *idxarr++ = idx;
nuclear@0 127 *idxarr++ = idx + vverts + 1;
nuclear@0 128 *idxarr++ = idx + 1;
nuclear@0 129
nuclear@0 130 *idxarr++ = idx;
nuclear@0 131 *idxarr++ = idx + vverts;
nuclear@0 132 *idxarr++ = idx + vverts + 1;
nuclear@0 133 }
nuclear@0 134
nuclear@0 135 v += dv;
nuclear@0 136 }
nuclear@0 137 u += du;
nuclear@0 138 }
nuclear@0 139
nuclear@0 140
nuclear@0 141 // now the cap!
nuclear@0 142 if(!capsub) {
nuclear@0 143 return;
nuclear@0 144 }
nuclear@0 145
nuclear@0 146 dv = 1.0 / (float)(capvverts - 1);
nuclear@0 147
nuclear@0 148 u = 0.0;
nuclear@0 149 for(int i=0; i<uverts; i++) {
nuclear@0 150 float theta = SURAD(u);
nuclear@0 151
nuclear@0 152 float v = 0.0;
nuclear@0 153 for(int j=0; j<capvverts; j++) {
nuclear@0 154 float r = v * rad;
nuclear@0 155
nuclear@0 156 Vector3 pos = cylvec(theta, height / 2.0) * r;
nuclear@0 157 pos.y = height / 2.0;
nuclear@0 158 Vector3 tang = (cylvec(theta + 0.1, 0.0) - cylvec(theta - 0.1, 0.0)).normalized();
nuclear@0 159
nuclear@0 160 *varr++ = pos;
nuclear@0 161 *narr++ = Vector3(0, 1, 0);
nuclear@0 162 *tarr++ = tang;
nuclear@0 163 *uvarr++ = Vector2(u * urange, v);
nuclear@0 164
nuclear@0 165 pos.y = -height / 2.0;
nuclear@0 166 *varr++ = pos;
nuclear@0 167 *narr++ = Vector3(0, -1, 0);
nuclear@0 168 *tarr++ = -tang;
nuclear@0 169 *uvarr++ = Vector2(u * urange, v);
nuclear@0 170
nuclear@0 171 if(i < usub && j < capsub) {
nuclear@0 172 unsigned int idx = num_body_verts + (i * capvverts + j) * 2;
nuclear@0 173
nuclear@0 174 unsigned int vidx[4] = {
nuclear@0 175 idx,
nuclear@0 176 idx + capvverts * 2,
nuclear@0 177 idx + (capvverts + 1) * 2,
nuclear@0 178 idx + 2
nuclear@0 179 };
nuclear@0 180
nuclear@0 181 *idxarr++ = vidx[0];
nuclear@0 182 *idxarr++ = vidx[2];
nuclear@0 183 *idxarr++ = vidx[1];
nuclear@0 184 *idxarr++ = vidx[0];
nuclear@0 185 *idxarr++ = vidx[3];
nuclear@0 186 *idxarr++ = vidx[2];
nuclear@0 187
nuclear@0 188 *idxarr++ = vidx[0] + 1;
nuclear@0 189 *idxarr++ = vidx[1] + 1;
nuclear@0 190 *idxarr++ = vidx[2] + 1;
nuclear@0 191 *idxarr++ = vidx[0] + 1;
nuclear@0 192 *idxarr++ = vidx[2] + 1;
nuclear@0 193 *idxarr++ = vidx[3] + 1;
nuclear@0 194 }
nuclear@0 195
nuclear@0 196 v += dv;
nuclear@0 197 }
nuclear@0 198 u += du;
nuclear@0 199 }
nuclear@0 200 }
nuclear@0 201
nuclear@0 202 // -------- cone --------
nuclear@0 203
nuclear@0 204 static Vector3 conevec(float theta, float y, float height)
nuclear@0 205 {
nuclear@0 206 float scale = 1.0 - y / height;
nuclear@0 207 return Vector3(sin(theta) * scale, y, cos(theta) * scale);
nuclear@0 208 }
nuclear@0 209
nuclear@0 210 void gen_cone(Mesh *mesh, float rad, float height, int usub, int vsub, int capsub, float urange, float vrange)
nuclear@0 211 {
nuclear@0 212 if(usub < 4) usub = 4;
nuclear@0 213 if(vsub < 1) vsub = 1;
nuclear@0 214
nuclear@0 215 int uverts = usub + 1;
nuclear@0 216 int vverts = vsub + 1;
nuclear@0 217
nuclear@0 218 int num_body_verts = uverts * vverts;
nuclear@0 219 int num_body_quads = usub * vsub;
nuclear@0 220 int num_body_tri = num_body_quads * 2;
nuclear@0 221
nuclear@0 222 int capvverts = capsub ? capsub + 1 : 0;
nuclear@0 223 int num_cap_verts = uverts * capvverts;
nuclear@0 224 int num_cap_quads = usub * capsub;
nuclear@0 225 int num_cap_tri = num_cap_quads * 2;
nuclear@0 226
nuclear@0 227 int num_verts = num_body_verts + num_cap_verts;
nuclear@0 228 int num_tri = num_body_tri + num_cap_tri;
nuclear@0 229
nuclear@0 230 mesh->clear();
nuclear@0 231 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@0 232 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@0 233 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@0 234 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@0 235 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@0 236
nuclear@0 237 float du = urange / (float)(uverts - 1);
nuclear@0 238 float dv = vrange / (float)(vverts - 1);
nuclear@0 239
nuclear@0 240 float u = 0.0;
nuclear@0 241 for(int i=0; i<uverts; i++) {
nuclear@0 242 float theta = SURAD(u);
nuclear@0 243
nuclear@0 244 float v = 0.0;
nuclear@0 245 for(int j=0; j<vverts; j++) {
nuclear@0 246 float y = v * height;
nuclear@0 247 Vector3 pos = conevec(theta, y, height);
nuclear@0 248
nuclear@0 249 Vector3 tang = (conevec(theta + 0.1, 0.0, height) - conevec(theta - 0.1, 0.0, height)).normalized();
nuclear@0 250 Vector3 bitang = (conevec(theta, y + 0.1, height) - pos).normalized();
nuclear@0 251
nuclear@0 252 *varr++ = Vector3(pos.x * rad, pos.y, pos.z * rad);
nuclear@0 253 *narr++ = cross_product(tang, bitang);
nuclear@0 254 *tarr++ = tang;
nuclear@0 255 *uvarr++ = Vector2(u * urange, v * vrange);
nuclear@0 256
nuclear@0 257 if(i < usub && j < vsub) {
nuclear@0 258 int idx = i * vverts + j;
nuclear@0 259
nuclear@0 260 *idxarr++ = idx;
nuclear@0 261 *idxarr++ = idx + vverts + 1;
nuclear@0 262 *idxarr++ = idx + 1;
nuclear@0 263
nuclear@0 264 *idxarr++ = idx;
nuclear@0 265 *idxarr++ = idx + vverts;
nuclear@0 266 *idxarr++ = idx + vverts + 1;
nuclear@0 267 }
nuclear@0 268
nuclear@0 269 v += dv;
nuclear@0 270 }
nuclear@0 271 u += du;
nuclear@0 272 }
nuclear@0 273
nuclear@0 274
nuclear@0 275 // now the bottom cap!
nuclear@0 276 if(!capsub) {
nuclear@0 277 return;
nuclear@0 278 }
nuclear@0 279
nuclear@0 280 dv = 1.0 / (float)(capvverts - 1);
nuclear@0 281
nuclear@0 282 u = 0.0;
nuclear@0 283 for(int i=0; i<uverts; i++) {
nuclear@0 284 float theta = SURAD(u);
nuclear@0 285
nuclear@0 286 float v = 0.0;
nuclear@0 287 for(int j=0; j<capvverts; j++) {
nuclear@0 288 float r = v * rad;
nuclear@0 289
nuclear@0 290 Vector3 pos = conevec(theta, 0.0, height) * r;
nuclear@0 291 Vector3 tang = (cylvec(theta + 0.1, 0.0) - cylvec(theta - 0.1, 0.0)).normalized();
nuclear@0 292
nuclear@0 293 *varr++ = pos;
nuclear@0 294 *narr++ = Vector3(0, -1, 0);
nuclear@0 295 *tarr++ = tang;
nuclear@0 296 *uvarr++ = Vector2(u * urange, v);
nuclear@0 297
nuclear@0 298 if(i < usub && j < capsub) {
nuclear@0 299 unsigned int idx = num_body_verts + i * capvverts + j;
nuclear@0 300
nuclear@0 301 unsigned int vidx[4] = {
nuclear@0 302 idx,
nuclear@0 303 idx + capvverts,
nuclear@0 304 idx + (capvverts + 1),
nuclear@0 305 idx + 1
nuclear@0 306 };
nuclear@0 307
nuclear@0 308 *idxarr++ = vidx[0];
nuclear@0 309 *idxarr++ = vidx[1];
nuclear@0 310 *idxarr++ = vidx[2];
nuclear@0 311 *idxarr++ = vidx[0];
nuclear@0 312 *idxarr++ = vidx[2];
nuclear@0 313 *idxarr++ = vidx[3];
nuclear@0 314 }
nuclear@0 315
nuclear@0 316 v += dv;
nuclear@0 317 }
nuclear@0 318 u += du;
nuclear@0 319 }
nuclear@0 320 }
nuclear@0 321
nuclear@0 322
nuclear@0 323 // -------- plane --------
nuclear@0 324
nuclear@0 325 void gen_plane(Mesh *mesh, float width, float height, int usub, int vsub)
nuclear@0 326 {
nuclear@0 327 if(usub < 1) usub = 1;
nuclear@0 328 if(vsub < 1) vsub = 1;
nuclear@0 329
nuclear@0 330 mesh->clear();
nuclear@0 331
nuclear@0 332 int uverts = usub + 1;
nuclear@0 333 int vverts = vsub + 1;
nuclear@0 334 int num_verts = uverts * vverts;
nuclear@0 335
nuclear@0 336 int num_quads = usub * vsub;
nuclear@0 337 int num_tri = num_quads * 2;
nuclear@0 338
nuclear@0 339 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@0 340 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@0 341 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@0 342 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@0 343 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@0 344
nuclear@0 345 float du = 1.0 / (float)usub;
nuclear@0 346 float dv = 1.0 / (float)vsub;
nuclear@0 347
nuclear@0 348 float u = 0.0;
nuclear@0 349 for(int i=0; i<uverts; i++) {
nuclear@0 350 float v = 0.0;
nuclear@0 351 for(int j=0; j<vverts; j++) {
nuclear@0 352 *varr++ = Vector3((u - 0.5) * width, (v - 0.5) * height, 0.0);
nuclear@0 353 *narr++ = Vector3(0, 0, 1);
nuclear@0 354 *tarr++ = Vector3(1, 0, 0);
nuclear@0 355 *uvarr++ = Vector2(u, v);
nuclear@0 356
nuclear@0 357 if(i < usub && j < vsub) {
nuclear@0 358 int idx = i * vverts + j;
nuclear@0 359
nuclear@0 360 *idxarr++ = idx;
nuclear@0 361 *idxarr++ = idx + vverts + 1;
nuclear@0 362 *idxarr++ = idx + 1;
nuclear@0 363
nuclear@0 364 *idxarr++ = idx;
nuclear@0 365 *idxarr++ = idx + vverts;
nuclear@0 366 *idxarr++ = idx + vverts + 1;
nuclear@0 367 }
nuclear@0 368
nuclear@0 369 v += dv;
nuclear@0 370 }
nuclear@0 371 u += du;
nuclear@0 372 }
nuclear@0 373 }