dos3d

annotate src/mingl.c @ 21:00d84ab1ef26

find changesets by author, revision, files, or words in the commit message
switched to wacom
author John Tsiombikas <nuclear@member.fsf.org>
date Sat, 21 Sep 2013 18:17:55 +0300
parents 1e9f0b3616fa
children f2c2e45e8edd
rev   line source
nuclear@0 1 #include <stdio.h>
nuclear@0 2 #include <stdlib.h>
nuclear@0 3 #include <string.h>
nuclear@0 4 #include <math.h>
nuclear@17 5 #include <limits.h>
nuclear@0 6 #include <assert.h>
nuclear@21 7 #include "vmath.h"
nuclear@0 8 #include "mingl.h"
nuclear@0 9 #include "mglimpl.h"
nuclear@0 10
nuclear@3 11
nuclear@0 12 #define DOT(a, b) ((a).x * (b).x + (a).y * (b).y + (a).z * (b).z)
nuclear@0 13
nuclear@11 14 #define NORMALIZE(v) \
nuclear@11 15 do { \
nuclear@11 16 float mag = sqrt(DOT(v, v)); \
nuclear@11 17 if(fabs(mag) > 1e-6) { \
nuclear@11 18 float invmag = 1.0 / mag; \
nuclear@11 19 (v).x *= invmag; \
nuclear@11 20 (v).y *= invmag; \
nuclear@11 21 (v).z *= invmag; \
nuclear@11 22 } \
nuclear@11 23 } while(0)
nuclear@11 24
nuclear@0 25 static void transform(vec4_t *res, vec4_t *v, float *mat);
nuclear@0 26 static void transform3(vec3_t *res, vec3_t *v, float *mat);
nuclear@0 27 static void vertex_proc(struct vertex *vert);
nuclear@3 28 static int calc_shiftmask(int val, int *shiftp, unsigned int *maskp);
nuclear@0 29
nuclear@0 30 static struct state st;
nuclear@0 31 static struct framebuffer fb;
nuclear@0 32
nuclear@0 33 int mgl_init(int width, int height)
nuclear@0 34 {
nuclear@0 35 int i;
nuclear@0 36
nuclear@0 37 st.flags = 0;
nuclear@0 38 st.mmode = 0;
nuclear@0 39
nuclear@0 40 mgl_front_face(MGL_CCW);
nuclear@0 41 mgl_cull_face(MGL_BACK);
nuclear@0 42
nuclear@0 43 st.curv.cidx = 0;
nuclear@0 44 st.curv.energy = 1.0;
nuclear@0 45 st.curv.norm.x = st.curv.norm.y = st.curv.norm.z = 0.0;
nuclear@0 46
nuclear@0 47 if(!(fb.pixels = malloc(width * height))) {
nuclear@0 48 return -1;
nuclear@0 49 }
nuclear@0 50 fb.width = width;
nuclear@0 51 fb.height = height;
nuclear@0 52 fb.zbuf = 0;
nuclear@0 53
nuclear@0 54 if(mgl_rast_init(&st, &fb) == -1) {
nuclear@0 55 free(fb.pixels);
nuclear@0 56 return -1;
nuclear@0 57 }
nuclear@0 58
nuclear@0 59 st.mtop[0] = st.mtop[1] = 0;
nuclear@0 60
nuclear@0 61 mgl_matrix_mode(MGL_MODELVIEW);
nuclear@0 62 mgl_load_identity();
nuclear@0 63 mgl_matrix_mode(MGL_PROJECTION);
nuclear@0 64 mgl_load_identity();
nuclear@0 65
nuclear@0 66 /* initial viewport in the size of the framebuffer */
nuclear@0 67 st.vp[0] = st.vp[1] = 0;
nuclear@0 68 st.vp[2] = width;
nuclear@0 69 st.vp[3] = height;
nuclear@0 70
nuclear@0 71 st.col_range = 256;
nuclear@0 72 for(i=0; i<MAX_LIGHTS; i++) {
nuclear@11 73 st.lpos[i].x = st.lpos[i].y = st.lpos[i].w = 0.0f;
nuclear@11 74 st.lpos[i].z = 1.0f;
nuclear@0 75 st.lint[i] = 0.0f;
nuclear@0 76 }
nuclear@0 77
nuclear@0 78 return 0;
nuclear@0 79 }
nuclear@0 80
nuclear@0 81 void mgl_free(void)
nuclear@0 82 {
nuclear@9 83 int i;
nuclear@9 84
nuclear@0 85 mgl_rast_cleanup();
nuclear@0 86 free(fb.pixels);
nuclear@9 87 fb.pixels = 0;
nuclear@9 88
nuclear@9 89 if(fb.zbuf) {
nuclear@9 90 for(i=0; i<fb.num_ztiles; i++) {
nuclear@9 91 free(fb.zbuf[i]);
nuclear@9 92 }
nuclear@9 93 free(fb.zbuf);
nuclear@9 94 fb.zbuf = 0;
nuclear@9 95 }
nuclear@0 96 }
nuclear@0 97
nuclear@0 98 unsigned char *mgl_framebuffer(void)
nuclear@0 99 {
nuclear@0 100 return fb.pixels;
nuclear@0 101 }
nuclear@0 102
nuclear@0 103 void mgl_clear(int cidx)
nuclear@0 104 {
nuclear@0 105 memset(fb.pixels, cidx, fb.width * fb.height);
nuclear@0 106 }
nuclear@0 107
nuclear@9 108 void mgl_clear_depth(void)
nuclear@9 109 {
nuclear@9 110 int i;
nuclear@9 111
nuclear@9 112 if(!fb.zbuf) {
nuclear@9 113 long num_pixels = (long)fb.width * (long)fb.height;
nuclear@9 114 fb.num_ztiles = (num_pixels + ZTILE_SIZE - 1) / ZTILE_SIZE;
nuclear@9 115
nuclear@9 116 if(!(fb.zbuf = malloc(fb.num_ztiles * sizeof *fb.zbuf))) {
nuclear@9 117 fprintf(stderr, "failed to allocate ztile array\n");
nuclear@9 118 abort();
nuclear@9 119 }
nuclear@9 120
nuclear@9 121 for(i=0; i<fb.num_ztiles; i++) {
nuclear@9 122 if(!(fb.zbuf[i] = malloc(ZTILE_SIZE * 2))) {
nuclear@9 123 fprintf(stderr, "failed to allocate ztile %d\n", i);
nuclear@9 124 abort();
nuclear@9 125 }
nuclear@9 126 memset(fb.zbuf[i], 0xff, ZTILE_SIZE * 2);
nuclear@9 127 }
nuclear@9 128 return;
nuclear@9 129 }
nuclear@9 130
nuclear@9 131 for(i=0; i<fb.num_ztiles; i++) {
nuclear@9 132 memset(fb.zbuf[i], 0xff, ZTILE_SIZE * 2);
nuclear@9 133 }
nuclear@9 134 }
nuclear@9 135
nuclear@0 136 void mgl_enable(unsigned int bit)
nuclear@0 137 {
nuclear@0 138 st.flags |= bit;
nuclear@0 139 }
nuclear@0 140
nuclear@0 141 void mgl_disable(unsigned int bit)
nuclear@0 142 {
nuclear@0 143 st.flags &= ~bit;
nuclear@0 144 }
nuclear@0 145
nuclear@3 146 int mgl_isenabled(unsigned int bit)
nuclear@3 147 {
nuclear@3 148 return (st.flags & bit) != 0;
nuclear@3 149 }
nuclear@3 150
nuclear@0 151 void mgl_front_face(int ff)
nuclear@0 152 {
nuclear@0 153 st.frontface = ff;
nuclear@0 154 }
nuclear@0 155
nuclear@0 156 void mgl_cull_face(int cf)
nuclear@0 157 {
nuclear@0 158 st.cullface = cf;
nuclear@0 159 }
nuclear@0 160
nuclear@0 161 void mgl_color_range(int rng)
nuclear@0 162 {
nuclear@0 163 st.col_range = rng;
nuclear@0 164 }
nuclear@0 165
nuclear@0 166 void mgl_light_intensity(int ltidx, float intens)
nuclear@0 167 {
nuclear@0 168 assert(ltidx >= 0 && ltidx < MAX_LIGHTS);
nuclear@0 169 st.lint[ltidx] = intens;
nuclear@0 170 }
nuclear@0 171
nuclear@11 172 void mgl_light_position(int ltidx, float x, float y, float z, float w)
nuclear@0 173 {
nuclear@11 174 vec4_t pos;
nuclear@0 175 assert(ltidx >= 0 && ltidx < MAX_LIGHTS);
nuclear@0 176
nuclear@11 177 pos.x = x;
nuclear@11 178 pos.y = y;
nuclear@11 179 pos.z = z;
nuclear@11 180 pos.w = w;
nuclear@11 181 transform(&st.lpos[ltidx], &pos, st.matrix[MGL_MODELVIEW][st.mtop[MGL_MODELVIEW]]);
nuclear@0 182
nuclear@11 183 if(fabs(st.lpos[ltidx].w) < 1e-6) {
nuclear@11 184 NORMALIZE(st.lpos[ltidx]);
nuclear@11 185 } else {
nuclear@11 186 st.lpos[ltidx].x /= st.lpos[ltidx].w;
nuclear@11 187 st.lpos[ltidx].y /= st.lpos[ltidx].w;
nuclear@11 188 st.lpos[ltidx].z /= st.lpos[ltidx].w;
nuclear@0 189 }
nuclear@0 190 }
nuclear@0 191
nuclear@0 192 void mgl_begin(int prim)
nuclear@0 193 {
nuclear@0 194 st.prim = prim;
nuclear@0 195 st.vidx = 0;
nuclear@0 196
nuclear@0 197 st.ord = st.frontface;
nuclear@0 198 if(st.cullface == MGL_FRONT) {
nuclear@0 199 st.ord = st.frontface == MGL_CCW ? MGL_CW : MGL_CCW;
nuclear@0 200 }
nuclear@0 201
nuclear@0 202 /* select the correct rasterizer according to state */
nuclear@0 203 mgl_rast_prepare();
nuclear@0 204 }
nuclear@0 205
nuclear@0 206 void mgl_end(void)
nuclear@0 207 {
nuclear@0 208 }
nuclear@0 209
nuclear@0 210 void mgl_vertex2f(float x, float y)
nuclear@0 211 {
nuclear@0 212 mgl_vertex4f(x, y, 0.0f, 1.0f);
nuclear@0 213 }
nuclear@0 214
nuclear@0 215 void mgl_vertex3f(float x, float y, float z)
nuclear@0 216 {
nuclear@0 217 mgl_vertex4f(x, y, z, 1.0f);
nuclear@0 218 }
nuclear@0 219
nuclear@0 220 void mgl_vertex4f(float x, float y, float z, float w)
nuclear@0 221 {
nuclear@0 222 st.v[st.vidx].pos.x = x;
nuclear@0 223 st.v[st.vidx].pos.y = y;
nuclear@0 224 st.v[st.vidx].pos.z = z;
nuclear@0 225 st.v[st.vidx].pos.w = w;
nuclear@0 226 st.v[st.vidx].cidx = st.curv.cidx;
nuclear@0 227 st.v[st.vidx].energy = st.curv.energy;
nuclear@0 228 st.v[st.vidx].norm = st.curv.norm;
nuclear@0 229 st.v[st.vidx].tc = st.curv.tc;
nuclear@0 230
nuclear@0 231 vertex_proc(st.v + st.vidx);
nuclear@0 232
nuclear@0 233 if(++st.vidx >= st.prim) {
nuclear@0 234 switch(st.prim) {
nuclear@0 235 case MGL_POINTS:
nuclear@0 236 mgl_draw_point(st.v);
nuclear@0 237 break;
nuclear@0 238 case MGL_LINES:
nuclear@0 239 mgl_draw_line(st.v, st.v + 1);
nuclear@0 240 break;
nuclear@0 241 case MGL_TRIANGLES:
nuclear@0 242 case MGL_QUADS:
nuclear@0 243 mgl_draw_poly(st.v, st.prim);
nuclear@0 244 break;
nuclear@0 245 default:
nuclear@0 246 fprintf(stderr, "invalid primitive: %d\n", st.prim);
nuclear@0 247 abort();
nuclear@0 248 }
nuclear@0 249 st.vidx = 0;
nuclear@0 250 }
nuclear@0 251 }
nuclear@0 252
nuclear@0 253 void mgl_color1f(float energy)
nuclear@0 254 {
nuclear@0 255 st.curv.energy = energy;
nuclear@0 256 }
nuclear@0 257
nuclear@0 258 void mgl_index(int c)
nuclear@0 259 {
nuclear@0 260 st.curv.cidx = c;
nuclear@0 261 }
nuclear@0 262
nuclear@0 263 void mgl_normal(float x, float y, float z)
nuclear@0 264 {
nuclear@0 265 st.curv.norm.x = x;
nuclear@0 266 st.curv.norm.y = y;
nuclear@0 267 st.curv.norm.z = z;
nuclear@0 268 }
nuclear@0 269
nuclear@0 270 void mgl_texcoord2f(float x, float y)
nuclear@0 271 {
nuclear@0 272 st.curv.tc.x = x;
nuclear@0 273 st.curv.tc.y = y;
nuclear@0 274 }
nuclear@0 275
nuclear@0 276 static void transform(vec4_t *res, vec4_t *v, float *mat)
nuclear@0 277 {
nuclear@0 278 res->x = mat[0] * v->x + mat[4] * v->y + mat[8] * v->z + mat[12] * v->w;
nuclear@0 279 res->y = mat[1] * v->x + mat[5] * v->y + mat[9] * v->z + mat[13] * v->w;
nuclear@0 280 res->z = mat[2] * v->x + mat[6] * v->y + mat[10] * v->z + mat[14] * v->w;
nuclear@0 281 res->w = mat[3] * v->x + mat[7] * v->y + mat[11] * v->z + mat[15] * v->w;
nuclear@0 282 }
nuclear@0 283
nuclear@0 284 /* the matrix is 4x4 (16 floats), just ignoring anything out of the 3x3 */
nuclear@0 285 static void transform3(vec3_t *res, vec3_t *v, float *mat)
nuclear@0 286 {
nuclear@0 287 res->x = mat[0] * v->x + mat[4] * v->y + mat[8] * v->z;
nuclear@0 288 res->y = mat[1] * v->x + mat[5] * v->y + mat[9] * v->z;
nuclear@0 289 res->z = mat[2] * v->x + mat[6] * v->y + mat[10] * v->z;
nuclear@0 290 }
nuclear@0 291
nuclear@0 292 static void vertex_proc(struct vertex *vert)
nuclear@0 293 {
nuclear@0 294 vec4_t pview, pclip;
nuclear@0 295
nuclear@0 296 float *mvmat = st.matrix[MGL_MODELVIEW][st.mtop[MGL_MODELVIEW]];
nuclear@0 297 float *pmat = st.matrix[MGL_PROJECTION][st.mtop[MGL_PROJECTION]];
nuclear@0 298
nuclear@0 299 /* modelview transformation */
nuclear@0 300 transform(&pview, &vert->pos, mvmat);
nuclear@0 301
nuclear@0 302 if(st.flags & MGL_LIGHTING) {
nuclear@0 303 if((st.flags & MGL_SMOOTH) || st.vidx == 0) {
nuclear@0 304 int i;
nuclear@0 305 vec3_t norm;
nuclear@0 306 float irrad = 0.0f;
nuclear@0 307
nuclear@0 308 transform3(&norm, &vert->norm, mvmat);
nuclear@0 309
nuclear@0 310 for(i=0; i<MAX_LIGHTS; i++) {
nuclear@0 311 if(st.lint[i] > 1e-6f) {
nuclear@11 312 float ndotl;
nuclear@11 313 vec3_t ldir;
nuclear@11 314
nuclear@11 315 if(st.lpos[i].w == 0.0) {
nuclear@11 316 ldir.x = st.lpos[i].x;
nuclear@11 317 ldir.y = st.lpos[i].y;
nuclear@11 318 ldir.z = st.lpos[i].z;
nuclear@11 319 } else {
nuclear@11 320 ldir.x = st.lpos[i].x - pview.x;
nuclear@11 321 ldir.y = st.lpos[i].y - pview.y;
nuclear@11 322 ldir.z = st.lpos[i].z - pview.z;
nuclear@11 323
nuclear@11 324 NORMALIZE(ldir);
nuclear@11 325 }
nuclear@11 326
nuclear@11 327 ndotl = DOT(norm, ldir);
nuclear@0 328 if(ndotl < 0.0) {
nuclear@0 329 ndotl = 0.0;
nuclear@0 330 }
nuclear@0 331 irrad += ndotl * st.lint[i];
nuclear@0 332 }
nuclear@0 333 }
nuclear@0 334 vert->energy = irrad;
nuclear@0 335 } else {
nuclear@0 336 vert->energy = st.v[0].energy;
nuclear@0 337 }
nuclear@0 338 }
nuclear@0 339
nuclear@0 340 transform(&pclip, &pview, pmat);
nuclear@0 341 /* TODO clipping in homogenous clip space */
nuclear@0 342
nuclear@0 343 if(pclip.w < 1e-6 && pclip.w > -1e-6) {
nuclear@0 344 vert->pos.x = vert->pos.y = vert->pos.z = vert->pos.w = 0.0f;
nuclear@0 345 return;
nuclear@0 346 }
nuclear@0 347
nuclear@0 348 /* perspective division */
nuclear@0 349 vert->pos.x = pclip.x / pclip.w;
nuclear@0 350 vert->pos.y = pclip.y / pclip.w;
nuclear@0 351 vert->pos.z = pclip.z / pclip.w;
nuclear@0 352 vert->pos.w = pclip.w;
nuclear@0 353
nuclear@0 354 /* viewport transformation */
nuclear@0 355 vert->pos.x = st.vp[0] + st.vp[2] * (vert->pos.x * 0.5 + 0.5);
nuclear@0 356 vert->pos.y = st.vp[1] + st.vp[3] * (-vert->pos.y * 0.5 + 0.5);
nuclear@0 357 }
nuclear@0 358
nuclear@0 359 void mgl_viewport(int x, int y, int width, int height)
nuclear@0 360 {
nuclear@0 361 st.vp[0] = x;
nuclear@0 362 st.vp[1] = y;
nuclear@0 363 st.vp[2] = width;
nuclear@0 364 st.vp[3] = height;
nuclear@0 365 }
nuclear@0 366
nuclear@0 367 void mgl_matrix_mode(int mmode)
nuclear@0 368 {
nuclear@0 369 st.mmode = mmode;
nuclear@0 370 }
nuclear@0 371
nuclear@0 372 void mgl_push_matrix(void)
nuclear@0 373 {
nuclear@0 374 float *topmat;
nuclear@0 375 if(st.mtop[st.mmode] >= MATRIX_STACK_SIZE - 1) {
nuclear@0 376 fprintf(stderr, "mgl_push_matrix: stack overflow\n");
nuclear@0 377 abort();
nuclear@0 378 }
nuclear@0 379
nuclear@0 380 topmat = st.matrix[st.mmode][st.mtop[st.mmode]];
nuclear@0 381 memcpy(topmat + 16, topmat, 16 * sizeof *topmat);
nuclear@0 382 st.mmode++;
nuclear@0 383 }
nuclear@0 384
nuclear@0 385 void mgl_pop_matrix(void)
nuclear@0 386 {
nuclear@0 387 if(st.mtop[st.mmode] <= 0) {
nuclear@0 388 fprintf(stderr, "mgl_pop_matrix: stack underflow\n");
nuclear@0 389 abort();
nuclear@0 390 }
nuclear@0 391 st.mtop[st.mmode]--;
nuclear@0 392 }
nuclear@0 393
nuclear@0 394 void mgl_load_matrix(float *mat)
nuclear@0 395 {
nuclear@0 396 float *dest = st.matrix[st.mmode][st.mtop[st.mmode]];
nuclear@0 397 memcpy(dest, mat, 16 * sizeof *dest);
nuclear@0 398 }
nuclear@0 399
nuclear@17 400 #define M(i,j) (((i) << 2) + (j))
nuclear@0 401 void mgl_mult_matrix(float *m2)
nuclear@0 402 {
nuclear@0 403 int i, j;
nuclear@0 404 float m1[16];
nuclear@0 405 float *dest = st.matrix[st.mmode][st.mtop[st.mmode]];
nuclear@0 406
nuclear@0 407 memcpy(m1, dest, sizeof m1);
nuclear@0 408
nuclear@0 409 for(i=0; i<4; i++) {
nuclear@0 410 for(j=0; j<4; j++) {
nuclear@0 411 dest[M(i,j)] = m1[M(0,j)] * m2[M(i,0)] +
nuclear@0 412 m1[M(1,j)] * m2[M(i,1)] +
nuclear@0 413 m1[M(2,j)] * m2[M(i,2)] +
nuclear@0 414 m1[M(3,j)] * m2[M(i,3)];
nuclear@0 415 }
nuclear@0 416 }
nuclear@0 417 }
nuclear@0 418
nuclear@0 419 void mgl_load_identity(void)
nuclear@0 420 {
nuclear@0 421 static float id[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@0 422 mgl_load_matrix((float*)id);
nuclear@0 423 }
nuclear@0 424
nuclear@0 425 void mgl_translate(float x, float y, float z)
nuclear@0 426 {
nuclear@0 427 float xform[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@0 428 xform[12] = x;
nuclear@0 429 xform[13] = y;
nuclear@0 430 xform[14] = z;
nuclear@0 431 mgl_mult_matrix(xform);
nuclear@0 432 }
nuclear@0 433
nuclear@0 434 void mgl_rotate(float deg, float x, float y, float z)
nuclear@0 435 {
nuclear@0 436 float xform[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@0 437
nuclear@0 438 float angle = M_PI * deg / 180.0f;
nuclear@0 439 float sina = sin(angle);
nuclear@0 440 float cosa = cos(angle);
nuclear@0 441 float one_minus_cosa = 1.0f - cosa;
nuclear@0 442 float nxsq = x * x;
nuclear@0 443 float nysq = y * y;
nuclear@0 444 float nzsq = z * z;
nuclear@0 445
nuclear@0 446 xform[0] = nxsq + (1.0f - nxsq) * cosa;
nuclear@0 447 xform[4] = x * y * one_minus_cosa - z * sina;
nuclear@0 448 xform[8] = x * z * one_minus_cosa + y * sina;
nuclear@0 449 xform[1] = x * y * one_minus_cosa + z * sina;
nuclear@0 450 xform[5] = nysq + (1.0 - nysq) * cosa;
nuclear@0 451 xform[9] = y * z * one_minus_cosa - x * sina;
nuclear@0 452 xform[2] = x * z * one_minus_cosa - y * sina;
nuclear@0 453 xform[6] = y * z * one_minus_cosa + x * sina;
nuclear@0 454 xform[10] = nzsq + (1.0 - nzsq) * cosa;
nuclear@0 455
nuclear@0 456 mgl_mult_matrix(xform);
nuclear@0 457 }
nuclear@0 458
nuclear@0 459 void mgl_scale(float x, float y, float z)
nuclear@0 460 {
nuclear@0 461 float xform[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@0 462 xform[0] = x;
nuclear@0 463 xform[5] = y;
nuclear@0 464 xform[10] = z;
nuclear@0 465 mgl_mult_matrix(xform);
nuclear@0 466 }
nuclear@0 467
nuclear@0 468 void gl_ortho(float left, float right, float bottom, float top, float nr, float fr)
nuclear@0 469 {
nuclear@0 470 float xform[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@0 471
nuclear@0 472 float dx = right - left;
nuclear@0 473 float dy = top - bottom;
nuclear@0 474 float dz = fr - nr;
nuclear@0 475
nuclear@0 476 float tx = -(right + left) / dx;
nuclear@0 477 float ty = -(top + bottom) / dy;
nuclear@0 478 float tz = -(fr + nr) / dz;
nuclear@0 479
nuclear@0 480 float sx = 2.0 / dx;
nuclear@0 481 float sy = 2.0 / dy;
nuclear@0 482 float sz = -2.0 / dz;
nuclear@0 483
nuclear@0 484 xform[0] = sx;
nuclear@0 485 xform[5] = sy;
nuclear@0 486 xform[10] = sz;
nuclear@0 487 xform[12] = tx;
nuclear@0 488 xform[13] = ty;
nuclear@0 489 xform[14] = tz;
nuclear@0 490
nuclear@0 491 mgl_mult_matrix(xform);
nuclear@0 492 }
nuclear@0 493
nuclear@0 494 void mgl_frustum(float left, float right, float bottom, float top, float nr, float fr)
nuclear@0 495 {
nuclear@0 496 float xform[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
nuclear@0 497
nuclear@0 498 float dx = right - left;
nuclear@0 499 float dy = top - bottom;
nuclear@0 500 float dz = fr - nr;
nuclear@0 501
nuclear@0 502 float a = (right + left) / dx;
nuclear@0 503 float b = (top + bottom) / dy;
nuclear@0 504 float c = -(fr + nr) / dz;
nuclear@0 505 float d = -2.0 * fr * nr / dz;
nuclear@0 506
nuclear@0 507 xform[0] = 2.0 * nr / dx;
nuclear@0 508 xform[5] = 2.0 * nr / dy;
nuclear@0 509 xform[8] = a;
nuclear@0 510 xform[9] = b;
nuclear@0 511 xform[10] = c;
nuclear@0 512 xform[11] = -1.0f;
nuclear@0 513 xform[14] = d;
nuclear@0 514
nuclear@0 515 mgl_mult_matrix(xform);
nuclear@0 516 }
nuclear@0 517
nuclear@0 518 void mgl_perspective(float vfov, float aspect, float nr, float fr)
nuclear@0 519 {
nuclear@0 520 float vfov_rad = M_PI * vfov / 180.0;
nuclear@0 521 float x = nr * tan(vfov_rad / 2.0);
nuclear@0 522 mgl_frustum(-aspect * x, aspect * x, -x, x, nr, fr);
nuclear@0 523 }
nuclear@3 524
nuclear@3 525 void mgl_teximage(int width, int height, unsigned char *pixels)
nuclear@3 526 {
nuclear@3 527 st.tex.width = width;
nuclear@3 528 st.tex.height = height;
nuclear@3 529 st.tex.pixels = pixels;
nuclear@3 530
nuclear@3 531 if(calc_shiftmask(width, &st.tex.xshift, &st.tex.xmask) == -1 ||
nuclear@3 532 calc_shiftmask(height, &st.tex.yshift, &st.tex.ymask) == -1) {
nuclear@3 533 st.tex.pixels = 0;
nuclear@3 534 }
nuclear@3 535 }
nuclear@3 536
nuclear@3 537 #define MAX_SHIFT 12
nuclear@3 538 static int calc_shiftmask(int val, int *shiftp, unsigned int *maskp)
nuclear@3 539 {
nuclear@3 540 int i;
nuclear@3 541
nuclear@3 542 for(i=0; i<MAX_SHIFT; i++) {
nuclear@3 543 if((val >> i) == 1) {
nuclear@3 544 *shiftp = i;
nuclear@17 545 *maskp = ~(UINT_MAX << i);
nuclear@3 546 return 0;
nuclear@3 547 }
nuclear@3 548 }
nuclear@3 549 return -1;
nuclear@3 550 }