rayzor: a9a948809c6f src/min3d.c

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view src/min3d.c @ 14:a9a948809c6f

starting the renderer screen, plus misc stuff

author	John Tsiombikas <nuclear@member.fsf.org>
date	Sun, 13 Apr 2014 08:06:21 +0300
parents	a68dbf80d547
children	79609d482762

line source

1 #include <stdlib.h>

2 #include <string.h>

3 #include <math.h>

4 #include "min3d.h"

5 #include "m3dimpl.h"

6 #include "logger.h"

8 #ifndef M_PI

9 #define M_PI 3.141592653

10 #endif

12 struct min3d_context *m3dctx;

14 int m3d_init(void)

15 {

16 if(!(m3dctx = malloc(sizeof *m3dctx))) {

17 return -1;

18 }

19 memset(m3dctx, 0, sizeof *m3dctx);

21 m3d_matrix_mode(M3D_PROJECTION);

22 m3d_load_identity();

23 m3d_matrix_mode(M3D_MODELVIEW);

24 m3d_load_identity();

26 m3d_color(1, 1, 1);

27 return 0;

28 }

30 void m3d_shutdown(void)

31 {

32 free(m3dctx);

33 }

35 void m3d_set_buffers(struct m3d_image *cbuf, uint16_t *zbuf)

36 {

37 m3dctx->cbuf = cbuf;

38 m3dctx->zbuf = zbuf;

40 m3d_viewport(0, 0, cbuf->xsz, cbuf->ysz);

41 }

43 void m3d_clear_color(float r, float g, float b)

44 {

45 m3dctx->clear_color[0] = (int)((r > 1.0 ? 1.0 : r) * 255.0);

46 m3dctx->clear_color[1] = (int)((g > 1.0 ? 1.0 : g) * 255.0);

47 m3dctx->clear_color[2] = (int)((b > 1.0 ? 1.0 : b) * 255.0);

48 }

50 void m3d_clear(unsigned int bmask)

51 {

52 int num_pixels = m3dctx->cbuf->xsz * m3dctx->cbuf->ysz;

53 if(bmask & M3D_COLOR_BUFFER_BIT) {

54 memset(m3dctx->cbuf->pixels, 0, num_pixels * 4);

55 /*

56 int i;

57 unsigned char *ptr = m3dctx->cbuf->pixels;

58 unsigned char r = m3dctx->clear_color[0];

59 unsigned char g = m3dctx->clear_color[1];

60 unsigned char b = m3dctx->clear_color[2];

61 for(i=0; i<num_pixels; i++) {

62 *ptr++ = r;

63 *ptr++ = g;

64 *ptr++ = b;

65 }*/

66 }

67 if(bmask & M3D_DEPTH_BUFFER_BIT) {

68 memset(m3dctx->zbuf, 0xff, num_pixels * sizeof *m3dctx->zbuf);

69 }

70 }

73 void m3d_enable(int bit)

74 {

75 m3dctx->state |= (1 << bit);

76 }

78 void m3d_disable(int bit)

79 {

80 m3dctx->state &= ~(1 << bit);

81 }

83 void m3d_viewport(int x, int y, int xsz, int ysz)

84 {

85 m3dctx->vport[0] = x;

86 m3dctx->vport[1] = y;

87 m3dctx->vport[2] = xsz;

88 m3dctx->vport[3] = ysz;

89 }

92 /* matrix stack */

93 void m3d_matrix_mode(int mode)

94 {

95 m3dctx->mmode = mode;

96 }

98 void m3d_push_matrix(void)

99 {

100 int mm = m3dctx->mmode;

101 int top = m3dctx->mstack[mm].top;

102 if(top < MSTACK_SIZE) {

103 float *cur = m3dctx->mstack[mm].m[top++];

104 memcpy(m3dctx->mstack[mm].m[top], cur, 16 * sizeof *cur);

105 m3dctx->mstack[mm].top = top;

106 }

107 }

108

109 void m3d_pop_matrix(void)

110 {

111 int mm = m3dctx->mmode;

112 if(m3dctx->mstack[mm].top > 0) {

113 --m3dctx->mstack[mm].top;

114 }

115 }

116

117 void m3d_load_identity(void)

118 {

119 static const float mid[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};

120 m3d_load_matrix(mid);

121 }

122

123 void m3d_load_matrix(const float *m)

124 {

125 int top = m3dctx->mstack[m3dctx->mmode].top;

126 memcpy(m3dctx->mstack[m3dctx->mmode].m[top], m, 16 * sizeof *m);

127 }

128

129 #define M(i,j) (((i) << 2) + (j))

130 void m3d_mult_matrix(const float *m2)

131 {

132 int i, j, top = m3dctx->mstack[m3dctx->mmode].top;

133 float m1[16];

134 float *dest = m3dctx->mstack[m3dctx->mmode].m[top];

135

136 memcpy(m1, dest, sizeof m1);

137

138 for(i=0; i<4; i++) {

139 for(j=0; j<4; j++) {

140 dest[M(i,j)] = m1[M(0,j)] * m2[M(i,0)] +

141 m1[M(1,j)] * m2[M(i,1)] +

142 m1[M(2,j)] * m2[M(i,2)] +

143 m1[M(3,j)] * m2[M(i,3)];

144 }

145 }

146 }

147

148 void m3d_translate(float x, float y, float z)

149 {

150 float m[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};

151 m[12] = x;

152 m[13] = y;

153 m[14] = z;

154 m3d_mult_matrix(m);

155 }

156

157 void m3d_rotate(float deg, float x, float y, float z)

158 {

159 float xform[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};

160

161 float angle = M_PI * deg / 180.0f;

162 float sina = sin(angle);

163 float cosa = cos(angle);

164 float one_minus_cosa = 1.0f - cosa;

165 float nxsq = x * x;

166 float nysq = y * y;

167 float nzsq = z * z;

168

169 xform[0] = nxsq + (1.0f - nxsq) * cosa;

170 xform[4] = x * y * one_minus_cosa - z * sina;

171 xform[8] = x * z * one_minus_cosa + y * sina;

172 xform[1] = x * y * one_minus_cosa + z * sina;

173 xform[5] = nysq + (1.0 - nysq) * cosa;

174 xform[9] = y * z * one_minus_cosa - x * sina;

175 xform[2] = x * z * one_minus_cosa - y * sina;

176 xform[6] = y * z * one_minus_cosa + x * sina;

177 xform[10] = nzsq + (1.0 - nzsq) * cosa;

178

179 m3d_mult_matrix(xform);

180 }

181

182 void m3d_scale(float x, float y, float z)

183 {

184 static float m[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};

185 m[0] = x;

186 m[5] = y;

187 m[10] = z;

188 m3d_mult_matrix(m);

189 }

190

191 void m3d_frustum(float left, float right, float bottom, float top, float nr, float fr)

192 {

193 float xform[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};

194

195 float dx = right - left;

196 float dy = top - bottom;

197 float dz = fr - nr;

198

199 float a = (right + left) / dx;

200 float b = (top + bottom) / dy;

201 float c = -(fr + nr) / dz;

202 float d = -2.0 * fr * nr / dz;

203

204 xform[0] = 2.0 * nr / dx;

205 xform[5] = 2.0 * nr / dy;

206 xform[8] = a;

207 xform[9] = b;

208 xform[10] = c;

209 xform[11] = -1.0f;

210 xform[14] = d;

211

212 m3d_mult_matrix(xform);

213 }

214

215 void m3d_perspective(float vfov, float aspect, float nr, float fr)

216 {

217 float vfov_rad = M_PI * vfov / 180.0;

218 float x = nr * tan(vfov_rad / 2.0);

219 m3d_frustum(-aspect * x, aspect * x, -x, x, nr, fr);

220 }

221

222 static void xform4(float *mat, float *vec)

223 {

224 float x = mat[0] * vec[0] + mat[4] * vec[1] + mat[8] * vec[2] + mat[12];

225 float y = mat[1] * vec[0] + mat[5] * vec[1] + mat[9] * vec[2] + mat[13];

226 float z = mat[2] * vec[0] + mat[6] * vec[1] + mat[10] * vec[2] + mat[14];

227 float w = mat[3] * vec[0] + mat[7] * vec[1] + mat[11] * vec[2] + mat[15];

228

229 vec[0] = x;

230 vec[1] = y;

231 vec[2] = z;

232 vec[3] = w;

233 }

234

235 static int proc_prim(int prim, struct min3d_vertex *res, struct min3d_vertex *v)

236 {

237 int i;

238 int vcount = prim;

239 int mvtop, ptop;

240 float *mvmat, *pmat;

241 int *vport = m3dctx->vport;

242

243 mvtop = m3dctx->mstack[M3D_MODELVIEW].top;

244 mvmat = m3dctx->mstack[M3D_MODELVIEW].m[mvtop];

245 ptop = m3dctx->mstack[M3D_PROJECTION].top;

246 pmat = m3dctx->mstack[M3D_PROJECTION].m[ptop];

247

248 /* transform to view space */

249 for(i=0; i<vcount; i++) {

250 res[i] = v[i];

251 xform4(mvmat, res[i].pos);

252 /* TODO: normal */

253 }

254

255 /* TODO: lighting */

256

257 /* project */

258 for(i=0; i<vcount; i++) {

259 xform4(pmat, res[i].pos);

260 }

261

262 /* clip */

263 switch(prim) {

264 case M3D_POINTS:

265 {

266 float w = res[0].pos[3];

267 if(res[0].pos[2] < -w || res[0].pos[2] >= w ||

268 res[0].pos[0] / w < -1 || res[0].pos[0] / w >= 1 ||

269 res[0].pos[1] / w < -1 || res[0].pos[1] / w >= 1) {

270 vcount = 0;

271 }

272 }

273 break;

274

275 default:

276 break; /* TODO */

277 }

278

279 /* perspective division & viewport */

280 for(i=0; i<vcount; i++) {

281 res[i].pos[0] /= res[i].pos[3];

282 res[i].pos[1] /= res[i].pos[3];

283 res[i].pos[2] /= res[i].pos[3];

284

285 res[i].pos[0] = (res[i].pos[0] * 0.5 + 0.5) * vport[2] + vport[0];

286 res[i].pos[1] = (-res[i].pos[1] * 0.5 + 0.5) * vport[3] + vport[1];

287 }

288 return vcount;

289 }

290

291 /* drawing */

292 void m3d_vertex_array(const float *varr)

293 {

294 m3dctx->vert_array = (float*)varr;

295 }

296

297 void m3d_normal_array(const float *narr)

298 {

299 m3dctx->norm_array = (float*)narr;

300 }

301

302 void m3d_color_array(const float *carr)

303 {

304 m3dctx->col_array = (float*)carr;

305 }

306

307 void m3d_texcoord_array(const float *tcarr)

308 {

309 m3dctx->tc_array = (float*)tcarr;

310 }

311

312

313 void m3d_draw(int prim, int vcount)

314 {

315 int i;

316 struct min3d_vertex v[4];

317 struct min3d_vertex resv[16];

318 const float *varr = m3dctx->vert_array;

319 const float *carr = m3dctx->col_array;

320

321 if(!varr) return;

322

323 for(i=0; i<vcount; i++) {

324 int r, g, b;

325 int idx = i % prim;

326

327 v[idx].pos[0] = *varr++;

328 v[idx].pos[1] = *varr++;

329 v[idx].pos[2] = *varr++;

330 v[idx].pos[3] = 1.0;

331 r = (carr ? *carr++ : m3dctx->im_color[0]) * 255.0;

332 g = (carr ? *carr++ : m3dctx->im_color[1]) * 255.0;

333 b = (carr ? *carr++ : m3dctx->im_color[2]) * 255.0;

334 v[idx].color = (r << 16) | (g << 8) | b;

335

336 if(idx == prim - 1) {

337 int resnum = proc_prim(prim, resv, v);

338 switch(resnum) {

339 case 1:

340 m3d_draw_point(resv);

341 break;

342

343 case 2:

344 m3d_draw_line(resv);

345 break;

346

347 default:

348 m3d_draw_poly(resv, resnum);

349 }

350 }

351 }

352 }

353

354 void m3d_draw_indexed(int prim, const unsigned int *idxarr, int icount)

355 {

356 int i, vcount = prim;

357 struct min3d_vertex v[4];

358 struct min3d_vertex resv[16];

359 const float *varr = m3dctx->vert_array;

360 const float *carr = m3dctx->col_array;

361

362 if(!varr) return;

363

364 for(i=0; i<icount; i++) {

365 int r, g, b;

366 int vnum = i % vcount;

367 int index = idxarr[i];

368

369 v[vnum].pos[0] = varr[index * 3];

370 v[vnum].pos[1] = varr[index * 3 + 1];

371 v[vnum].pos[2] = varr[index * 3 + 2];

372 v[vnum].pos[3] = 1.0;

373 r = (carr ? carr[index * 3] : m3dctx->im_color[0]) * 255.0;

374 g = (carr ? carr[index * 3 + 1] : m3dctx->im_color[1]) * 255.0;

375 b = (carr ? carr[index * 3 + 2] : m3dctx->im_color[2]) * 255.0;

376 v[vnum].color = (r << 16) | (g << 8) | b;

377

378 if(vnum == vcount - 1) {

379 int resnum = proc_prim(prim, resv, v);

380 switch(resnum) {

381 case 1:

382 m3d_draw_point(resv);

383 break;

384

385 case 2:

386 m3d_draw_line(resv);

387 break;

388

389 default:

390 m3d_draw_poly(resv, resnum);

391 }

392 }

393 }

394 }

395

396 void m3d_begin(int prim)

397 {

398 m3dctx->im_prim = prim;

399 m3dctx->im_idx = 0;

400

401 m3dctx->vert_array = m3dctx->im_varr;

402 m3dctx->norm_array = 0;

403 m3dctx->col_array = 0;

404 m3dctx->tc_array = 0;

405 }

406

407 void m3d_end(void)

408 {

409 }

410

411 void m3d_vertex(float x, float y, float z)

412 {

413 int nverts = m3dctx->im_prim;

414 int idx = m3dctx->im_idx;

415 float *v = m3dctx->vert_array + idx * 3;

416

417 v[0] = x;

418 v[1] = y;

419 v[2] = z;

420

421 if(m3dctx->norm_array) {

422 float *ptr = m3dctx->im_narr + idx * 3;

423 ptr[0] = m3dctx->im_normal[0];

424 ptr[1] = m3dctx->im_normal[1];

425 ptr[2] = m3dctx->im_normal[2];

426 }

427 if(m3dctx->col_array) {

428 float *ptr = m3dctx->im_carr + idx * 3;

429 ptr[0] = m3dctx->im_color[0];

430 ptr[1] = m3dctx->im_color[1];

431 ptr[2] = m3dctx->im_color[2];

432 }

433 if(m3dctx->tc_array) {

434 float *ptr = m3dctx->im_texcoord + idx * 2;

435 ptr[0] = m3dctx->im_texcoord[0];

436 ptr[1] = m3dctx->im_texcoord[1];

437 }

438

439 if(++idx == nverts) {

440 m3d_draw(m3dctx->im_prim, nverts);

441 idx = 0;

442 }

443

444 m3dctx->im_idx = idx;

445 }

446

447 void m3d_normal(float x, float y, float z)

448 {

449 m3dctx->im_normal[0] = x;

450 m3dctx->im_normal[1] = y;

451 m3dctx->im_normal[2] = z;

452 }

453

454 void m3d_color(float x, float y, float z)

455 {

456 m3dctx->im_color[0] = x;

457 m3dctx->im_color[1] = y;

458 m3dctx->im_color[2] = z;

459 }

460

461 void m3d_texcoord(float x, float y)

462 {

463 m3dctx->im_texcoord[0] = x;

464 m3dctx->im_texcoord[1] = y;

465 }