goat3dgfx

annotate src/meshgen.cc @ 15:7d6b667821cf

find changesets by author, revision, files, or words in the commit message
wrapped everything in the goatgfx namespace
author John Tsiombikas <nuclear@member.fsf.org>
date Sat, 30 Nov 2013 20:52:21 +0200
parents 1873dfd13f2d
children f2da87b02fcd
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@15 5 using namespace goatgfx;
nuclear@15 6
nuclear@0 7 // -------- sphere --------
nuclear@0 8
nuclear@0 9 #define SURAD(u) ((u) * 2.0 * M_PI)
nuclear@0 10 #define SVRAD(v) ((v) * M_PI)
nuclear@0 11
nuclear@0 12 static Vector3 sphvec(float theta, float phi)
nuclear@0 13 {
nuclear@0 14 return Vector3(sin(theta) * sin(phi),
nuclear@0 15 cos(phi),
nuclear@0 16 cos(theta) * sin(phi));
nuclear@0 17 }
nuclear@0 18
nuclear@0 19 void gen_sphere(Mesh *mesh, float rad, int usub, int vsub, float urange, float vrange)
nuclear@0 20 {
nuclear@0 21 if(usub < 4) usub = 4;
nuclear@0 22 if(vsub < 2) vsub = 2;
nuclear@0 23
nuclear@0 24 int uverts = usub + 1;
nuclear@0 25 int vverts = vsub + 1;
nuclear@0 26
nuclear@0 27 int num_verts = uverts * vverts;
nuclear@0 28 int num_quads = usub * vsub;
nuclear@0 29 int num_tri = num_quads * 2;
nuclear@0 30
nuclear@0 31 mesh->clear();
nuclear@0 32 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@0 33 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@0 34 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@0 35 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@0 36 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@0 37
nuclear@0 38 float du = urange / (float)(uverts - 1);
nuclear@0 39 float dv = vrange / (float)(vverts - 1);
nuclear@0 40
nuclear@0 41 float u = 0.0;
nuclear@0 42 for(int i=0; i<uverts; i++) {
nuclear@0 43 float theta = SURAD(u * urange);
nuclear@0 44
nuclear@0 45 float v = 0.0;
nuclear@0 46 for(int j=0; j<vverts; j++) {
nuclear@0 47 float phi = SVRAD(v * vrange);
nuclear@0 48
nuclear@0 49 Vector3 pos = sphvec(theta, phi);
nuclear@0 50
nuclear@0 51 *varr++ = pos * rad;
nuclear@0 52 *narr++ = pos;
nuclear@0 53 *tarr++ = (sphvec(theta + 0.1, M_PI / 2.0) - sphvec(theta - 0.1, M_PI / 2.0)).normalized();
nuclear@0 54 *uvarr++ = Vector2(u * urange, v * vrange);
nuclear@0 55
nuclear@0 56 if(i < usub && j < vsub) {
nuclear@0 57 int idx = i * vverts + j;
nuclear@0 58 *idxarr++ = idx;
nuclear@0 59 *idxarr++ = idx + 1;
nuclear@0 60 *idxarr++ = idx + vverts + 1;
nuclear@0 61
nuclear@0 62 *idxarr++ = idx;
nuclear@0 63 *idxarr++ = idx + vverts + 1;
nuclear@0 64 *idxarr++ = idx + vverts;
nuclear@0 65 }
nuclear@0 66
nuclear@0 67 v += dv;
nuclear@0 68 }
nuclear@0 69 u += du;
nuclear@0 70 }
nuclear@0 71 }
nuclear@0 72
nuclear@0 73
nuclear@0 74 // -------- cylinder --------
nuclear@0 75
nuclear@0 76 static Vector3 cylvec(float theta, float height)
nuclear@0 77 {
nuclear@0 78 return Vector3(sin(theta), height, cos(theta));
nuclear@0 79 }
nuclear@0 80
nuclear@0 81 void gen_cylinder(Mesh *mesh, float rad, float height, int usub, int vsub, int capsub, float urange, float vrange)
nuclear@0 82 {
nuclear@0 83 if(usub < 4) usub = 4;
nuclear@0 84 if(vsub < 1) vsub = 1;
nuclear@0 85
nuclear@0 86 int uverts = usub + 1;
nuclear@0 87 int vverts = vsub + 1;
nuclear@0 88
nuclear@0 89 int num_body_verts = uverts * vverts;
nuclear@0 90 int num_body_quads = usub * vsub;
nuclear@0 91 int num_body_tri = num_body_quads * 2;
nuclear@0 92
nuclear@0 93 int capvverts = capsub ? capsub + 1 : 0;
nuclear@0 94 int num_cap_verts = uverts * capvverts;
nuclear@0 95 int num_cap_quads = usub * capsub;
nuclear@0 96 int num_cap_tri = num_cap_quads * 2;
nuclear@0 97
nuclear@0 98 int num_verts = num_body_verts + num_cap_verts * 2;
nuclear@0 99 int num_tri = num_body_tri + num_cap_tri * 2;
nuclear@0 100
nuclear@0 101 mesh->clear();
nuclear@0 102 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@0 103 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@0 104 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@0 105 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@0 106 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@0 107
nuclear@0 108 float du = urange / (float)(uverts - 1);
nuclear@0 109 float dv = vrange / (float)(vverts - 1);
nuclear@0 110
nuclear@0 111 float u = 0.0;
nuclear@0 112 for(int i=0; i<uverts; i++) {
nuclear@0 113 float theta = SURAD(u);
nuclear@0 114
nuclear@0 115 float v = 0.0;
nuclear@0 116 for(int j=0; j<vverts; j++) {
nuclear@0 117 float y = (v - 0.5) * height;
nuclear@0 118 Vector3 pos = cylvec(theta, y);
nuclear@0 119
nuclear@0 120 *varr++ = Vector3(pos.x * rad, pos.y, pos.z * rad);
nuclear@0 121 *narr++ = Vector3(pos.x, 0.0, pos.z);
nuclear@0 122 *tarr++ = (cylvec(theta + 0.1, 0.0) - cylvec(theta - 0.1, 0.0)).normalized();
nuclear@0 123 *uvarr++ = Vector2(u * urange, v * vrange);
nuclear@0 124
nuclear@0 125 if(i < usub && j < vsub) {
nuclear@0 126 int idx = i * vverts + j;
nuclear@0 127
nuclear@0 128 *idxarr++ = idx;
nuclear@0 129 *idxarr++ = idx + vverts + 1;
nuclear@0 130 *idxarr++ = idx + 1;
nuclear@0 131
nuclear@0 132 *idxarr++ = idx;
nuclear@0 133 *idxarr++ = idx + vverts;
nuclear@0 134 *idxarr++ = idx + vverts + 1;
nuclear@0 135 }
nuclear@0 136
nuclear@0 137 v += dv;
nuclear@0 138 }
nuclear@0 139 u += du;
nuclear@0 140 }
nuclear@0 141
nuclear@0 142
nuclear@0 143 // now the cap!
nuclear@0 144 if(!capsub) {
nuclear@0 145 return;
nuclear@0 146 }
nuclear@0 147
nuclear@0 148 dv = 1.0 / (float)(capvverts - 1);
nuclear@0 149
nuclear@0 150 u = 0.0;
nuclear@0 151 for(int i=0; i<uverts; i++) {
nuclear@0 152 float theta = SURAD(u);
nuclear@0 153
nuclear@0 154 float v = 0.0;
nuclear@0 155 for(int j=0; j<capvverts; j++) {
nuclear@0 156 float r = v * rad;
nuclear@0 157
nuclear@0 158 Vector3 pos = cylvec(theta, height / 2.0) * r;
nuclear@0 159 pos.y = height / 2.0;
nuclear@0 160 Vector3 tang = (cylvec(theta + 0.1, 0.0) - cylvec(theta - 0.1, 0.0)).normalized();
nuclear@0 161
nuclear@0 162 *varr++ = pos;
nuclear@0 163 *narr++ = Vector3(0, 1, 0);
nuclear@0 164 *tarr++ = tang;
nuclear@0 165 *uvarr++ = Vector2(u * urange, v);
nuclear@0 166
nuclear@0 167 pos.y = -height / 2.0;
nuclear@0 168 *varr++ = pos;
nuclear@0 169 *narr++ = Vector3(0, -1, 0);
nuclear@0 170 *tarr++ = -tang;
nuclear@0 171 *uvarr++ = Vector2(u * urange, v);
nuclear@0 172
nuclear@0 173 if(i < usub && j < capsub) {
nuclear@0 174 unsigned int idx = num_body_verts + (i * capvverts + j) * 2;
nuclear@0 175
nuclear@0 176 unsigned int vidx[4] = {
nuclear@0 177 idx,
nuclear@0 178 idx + capvverts * 2,
nuclear@0 179 idx + (capvverts + 1) * 2,
nuclear@0 180 idx + 2
nuclear@0 181 };
nuclear@0 182
nuclear@0 183 *idxarr++ = vidx[0];
nuclear@0 184 *idxarr++ = vidx[2];
nuclear@0 185 *idxarr++ = vidx[1];
nuclear@0 186 *idxarr++ = vidx[0];
nuclear@0 187 *idxarr++ = vidx[3];
nuclear@0 188 *idxarr++ = vidx[2];
nuclear@0 189
nuclear@0 190 *idxarr++ = vidx[0] + 1;
nuclear@0 191 *idxarr++ = vidx[1] + 1;
nuclear@0 192 *idxarr++ = vidx[2] + 1;
nuclear@0 193 *idxarr++ = vidx[0] + 1;
nuclear@0 194 *idxarr++ = vidx[2] + 1;
nuclear@0 195 *idxarr++ = vidx[3] + 1;
nuclear@0 196 }
nuclear@0 197
nuclear@0 198 v += dv;
nuclear@0 199 }
nuclear@0 200 u += du;
nuclear@0 201 }
nuclear@0 202 }
nuclear@0 203
nuclear@0 204 // -------- cone --------
nuclear@0 205
nuclear@0 206 static Vector3 conevec(float theta, float y, float height)
nuclear@0 207 {
nuclear@0 208 float scale = 1.0 - y / height;
nuclear@0 209 return Vector3(sin(theta) * scale, y, cos(theta) * scale);
nuclear@0 210 }
nuclear@0 211
nuclear@0 212 void gen_cone(Mesh *mesh, float rad, float height, int usub, int vsub, int capsub, float urange, float vrange)
nuclear@0 213 {
nuclear@0 214 if(usub < 4) usub = 4;
nuclear@0 215 if(vsub < 1) vsub = 1;
nuclear@0 216
nuclear@0 217 int uverts = usub + 1;
nuclear@0 218 int vverts = vsub + 1;
nuclear@0 219
nuclear@0 220 int num_body_verts = uverts * vverts;
nuclear@0 221 int num_body_quads = usub * vsub;
nuclear@0 222 int num_body_tri = num_body_quads * 2;
nuclear@0 223
nuclear@0 224 int capvverts = capsub ? capsub + 1 : 0;
nuclear@0 225 int num_cap_verts = uverts * capvverts;
nuclear@0 226 int num_cap_quads = usub * capsub;
nuclear@0 227 int num_cap_tri = num_cap_quads * 2;
nuclear@0 228
nuclear@0 229 int num_verts = num_body_verts + num_cap_verts;
nuclear@0 230 int num_tri = num_body_tri + num_cap_tri;
nuclear@0 231
nuclear@0 232 mesh->clear();
nuclear@0 233 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@0 234 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@0 235 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@0 236 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@0 237 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@0 238
nuclear@0 239 float du = urange / (float)(uverts - 1);
nuclear@0 240 float dv = vrange / (float)(vverts - 1);
nuclear@0 241
nuclear@0 242 float u = 0.0;
nuclear@0 243 for(int i=0; i<uverts; i++) {
nuclear@0 244 float theta = SURAD(u);
nuclear@0 245
nuclear@0 246 float v = 0.0;
nuclear@0 247 for(int j=0; j<vverts; j++) {
nuclear@0 248 float y = v * height;
nuclear@0 249 Vector3 pos = conevec(theta, y, height);
nuclear@0 250
nuclear@0 251 Vector3 tang = (conevec(theta + 0.1, 0.0, height) - conevec(theta - 0.1, 0.0, height)).normalized();
nuclear@0 252 Vector3 bitang = (conevec(theta, y + 0.1, height) - pos).normalized();
nuclear@0 253
nuclear@0 254 *varr++ = Vector3(pos.x * rad, pos.y, pos.z * rad);
nuclear@0 255 *narr++ = cross_product(tang, bitang);
nuclear@0 256 *tarr++ = tang;
nuclear@0 257 *uvarr++ = Vector2(u * urange, v * vrange);
nuclear@0 258
nuclear@0 259 if(i < usub && j < vsub) {
nuclear@0 260 int idx = i * vverts + j;
nuclear@0 261
nuclear@0 262 *idxarr++ = idx;
nuclear@0 263 *idxarr++ = idx + vverts + 1;
nuclear@0 264 *idxarr++ = idx + 1;
nuclear@0 265
nuclear@0 266 *idxarr++ = idx;
nuclear@0 267 *idxarr++ = idx + vverts;
nuclear@0 268 *idxarr++ = idx + vverts + 1;
nuclear@0 269 }
nuclear@0 270
nuclear@0 271 v += dv;
nuclear@0 272 }
nuclear@0 273 u += du;
nuclear@0 274 }
nuclear@0 275
nuclear@0 276
nuclear@0 277 // now the bottom cap!
nuclear@0 278 if(!capsub) {
nuclear@0 279 return;
nuclear@0 280 }
nuclear@0 281
nuclear@0 282 dv = 1.0 / (float)(capvverts - 1);
nuclear@0 283
nuclear@0 284 u = 0.0;
nuclear@0 285 for(int i=0; i<uverts; i++) {
nuclear@0 286 float theta = SURAD(u);
nuclear@0 287
nuclear@0 288 float v = 0.0;
nuclear@0 289 for(int j=0; j<capvverts; j++) {
nuclear@0 290 float r = v * rad;
nuclear@0 291
nuclear@0 292 Vector3 pos = conevec(theta, 0.0, height) * r;
nuclear@0 293 Vector3 tang = (cylvec(theta + 0.1, 0.0) - cylvec(theta - 0.1, 0.0)).normalized();
nuclear@0 294
nuclear@0 295 *varr++ = pos;
nuclear@0 296 *narr++ = Vector3(0, -1, 0);
nuclear@0 297 *tarr++ = tang;
nuclear@0 298 *uvarr++ = Vector2(u * urange, v);
nuclear@0 299
nuclear@0 300 if(i < usub && j < capsub) {
nuclear@0 301 unsigned int idx = num_body_verts + i * capvverts + j;
nuclear@0 302
nuclear@0 303 unsigned int vidx[4] = {
nuclear@0 304 idx,
nuclear@0 305 idx + capvverts,
nuclear@0 306 idx + (capvverts + 1),
nuclear@0 307 idx + 1
nuclear@0 308 };
nuclear@0 309
nuclear@0 310 *idxarr++ = vidx[0];
nuclear@0 311 *idxarr++ = vidx[1];
nuclear@0 312 *idxarr++ = vidx[2];
nuclear@0 313 *idxarr++ = vidx[0];
nuclear@0 314 *idxarr++ = vidx[2];
nuclear@0 315 *idxarr++ = vidx[3];
nuclear@0 316 }
nuclear@0 317
nuclear@0 318 v += dv;
nuclear@0 319 }
nuclear@0 320 u += du;
nuclear@0 321 }
nuclear@0 322 }
nuclear@0 323
nuclear@0 324
nuclear@0 325 // -------- plane --------
nuclear@0 326
nuclear@0 327 void gen_plane(Mesh *mesh, float width, float height, int usub, int vsub)
nuclear@0 328 {
nuclear@0 329 if(usub < 1) usub = 1;
nuclear@0 330 if(vsub < 1) vsub = 1;
nuclear@0 331
nuclear@0 332 mesh->clear();
nuclear@0 333
nuclear@0 334 int uverts = usub + 1;
nuclear@0 335 int vverts = vsub + 1;
nuclear@0 336 int num_verts = uverts * vverts;
nuclear@0 337
nuclear@0 338 int num_quads = usub * vsub;
nuclear@0 339 int num_tri = num_quads * 2;
nuclear@0 340
nuclear@0 341 Vector3 *varr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_VERTEX, 3, num_verts, 0);
nuclear@0 342 Vector3 *narr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_NORMAL, 3, num_verts, 0);
nuclear@0 343 Vector3 *tarr = (Vector3*)mesh->set_attrib_data(MESH_ATTR_TANGENT, 3, num_verts, 0);
nuclear@0 344 Vector2 *uvarr = (Vector2*)mesh->set_attrib_data(MESH_ATTR_TEXCOORD, 2, num_verts, 0);
nuclear@0 345 unsigned int *idxarr = mesh->set_index_data(num_tri * 3, 0);
nuclear@0 346
nuclear@0 347 float du = 1.0 / (float)usub;
nuclear@0 348 float dv = 1.0 / (float)vsub;
nuclear@0 349
nuclear@0 350 float u = 0.0;
nuclear@0 351 for(int i=0; i<uverts; i++) {
nuclear@0 352 float v = 0.0;
nuclear@0 353 for(int j=0; j<vverts; j++) {
nuclear@0 354 *varr++ = Vector3((u - 0.5) * width, (v - 0.5) * height, 0.0);
nuclear@0 355 *narr++ = Vector3(0, 0, 1);
nuclear@0 356 *tarr++ = Vector3(1, 0, 0);
nuclear@0 357 *uvarr++ = Vector2(u, v);
nuclear@0 358
nuclear@0 359 if(i < usub && j < vsub) {
nuclear@0 360 int idx = i * vverts + j;
nuclear@0 361
nuclear@0 362 *idxarr++ = idx;
nuclear@0 363 *idxarr++ = idx + vverts + 1;
nuclear@0 364 *idxarr++ = idx + 1;
nuclear@0 365
nuclear@0 366 *idxarr++ = idx;
nuclear@0 367 *idxarr++ = idx + vverts;
nuclear@0 368 *idxarr++ = idx + vverts + 1;
nuclear@0 369 }
nuclear@0 370
nuclear@0 371 v += dv;
nuclear@0 372 }
nuclear@0 373 u += du;
nuclear@0 374 }
nuclear@0 375 }