gba-x3dtest: 0a7f402892b3 src/x3d.c

gba-x3dtest

view src/x3d.c @ 17:0a7f402892b3

texture mapping

author	John Tsiombikas <nuclear@member.fsf.org>
date	Thu, 26 Jun 2014 06:57:51 +0300
parents	b755fb002f17
children	62390f9cc93e

line source

1 #include "config.h"

2 #include <stdio.h>

3 #include <string.h>

4 #include <math.h>

5 #include "x3d.h"

6 #include "fixed.h"

7 #include "sincos.h"

8 #include "logger.h"

9 #include "polyfill.h"

10 #include "gbasys.h"

11 #include "x3d_impl.h"

13 int dbg_fill_dump;

15 #define MAT_STACK_SIZE 4

17 struct matrix {

18 int32_t m[12];

19 };

21 static void proc_vertex(const int32_t *vin, const int32_t *cin, const int32_t *tin,

22 pvec3 *vout, pvec3 *cout, pvec2 *tout);

23 static int dump_frame(struct pixel_buffer *frame);

26 static int32_t proj_fov = M_PI_X16;

27 static int32_t proj_aspect = 65536;

28 static int32_t inv_proj_aspect = 65536;

29 static int32_t proj_near = ftox16(0.5);

30 static int32_t proj_far = 500 << 16;

31 static int32_t inv_tan_half_xfov, inv_tan_half_yfov;

33 #define ID_INIT {65536, 0, 0, 0, 0, 65536, 0, 0, 0, 0, 65536, 0}

35 static struct matrix identity = { ID_INIT };

37 static short mtop;

38 static struct matrix mstack[MAT_STACK_SIZE] = { {ID_INIT}, {ID_INIT} };

40 static const int32_t *vertex_array;

41 static unsigned short vertex_count;

42 static const int32_t *color_array;

43 static unsigned short color_count;

44 static const int32_t *texcoord_array;

45 static unsigned short texcoord_count;

47 static int32_t im_color[3];

48 static int32_t im_texcoord[2];

49 static uint8_t im_color_index;

51 #define MAX_TEXTURES 64

52 static struct texture textures[MAX_TEXTURES];

53 static short cur_tex = -1;

56 void x3d_projection(int fov, int32_t aspect, int32_t nearz, int32_t farz)

57 {

58 proj_fov = (M_PI_X16 * fov) / 180;

59 proj_aspect = aspect;

60 inv_proj_aspect = x16div(65536, proj_aspect);

61 proj_near = nearz;

62 proj_far = farz;

64 inv_tan_half_yfov = (int32_t)(65536.0 / tan(0.5 * proj_fov / 65536.0));

65 inv_tan_half_xfov = x16mul(inv_tan_half_yfov, aspect);

66 }

68 int x3d_push_matrix(void)

69 {

70 short newtop = mtop + 1;

71 if(newtop >= MAT_STACK_SIZE) {

72 return -1;

73 }

74 memcpy(mstack + newtop, mstack + mtop, sizeof *mstack);

75 mtop = newtop;

76 return 0;

77 }

79 int x3d_pop_matrix(void)

80 {

81 if(mtop <= 0) {

82 return -1;

83 }

84 --mtop;

85 return 0;

86 }

88 void x3d_load_matrix(int32_t *m)

89 {

90 memcpy(mstack[mtop].m, m, sizeof *mstack);

91 }

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

95 void x3d_mult_matrix(int32_t *m)

96 {

97 int i, j;

98 struct matrix tmp;

100 memcpy(tmp.m, mstack[mtop].m, sizeof tmp);

101

102 for(i=0; i<3; i++) {

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

104 mstack[mtop].m[M(i, j)] =

105 x16mul(m[M(0, j)], tmp.m[M(i, 0)]) +

106 x16mul(m[M(1, j)], tmp.m[M(i, 1)]) +

107 x16mul(m[M(2, j)], tmp.m[M(i, 2)]);

108 }

109 mstack[mtop].m[M(i, 3)] += tmp.m[M(i, 3)];

110 }

111 }

112

113 void x3d_load_identity(void)

114 {

115 memcpy(mstack[mtop].m, identity.m, sizeof identity);

116 }

117

118 void x3d_translate(int32_t x, int32_t y, int32_t z)

119 {

120 int32_t m[] = ID_INIT;

121 m[3] = x;

122 m[7] = y;

123 m[11] = z;

124

125 x3d_mult_matrix(m);

126 }

127

128 void x3d_rotate(int32_t deg, int32_t x, int32_t y, int32_t z)

129 {

130 int32_t xform[] = ID_INIT;

131

132 int32_t angle = x16mul(M_PI_X16, deg) / 180;

133 int32_t sina = sin_x16(angle);

134 int32_t cosa = cos_x16(angle);

135 int32_t one_minus_cosa = 65536 - cosa;

136 int32_t nxsq = x16sq(x);

137 int32_t nysq = x16sq(y);

138 int32_t nzsq = x16sq(z);

139

140 xform[0] = nxsq + x16mul(65536 - nxsq, cosa);

141 xform[4] = x16mul(x16mul(x, y), one_minus_cosa) - x16mul(z, sina);

142 xform[8] = x16mul(x16mul(x, z), one_minus_cosa) + x16mul(y, sina);

143 xform[1] = x16mul(x16mul(x, y), one_minus_cosa) + x16mul(z, sina);

144 xform[5] = nysq + x16mul(65536 - nysq, cosa);

145 xform[9] = x16mul(x16mul(y, z), one_minus_cosa) - x16mul(x, sina);

146 xform[2] = x16mul(x16mul(x, z), one_minus_cosa) - x16mul(y, sina);

147 xform[6] = x16mul(x16mul(y, z), one_minus_cosa) + x16mul(x, sina);

148 xform[10] = nzsq + x16mul(65536 - nzsq, cosa);

149

150 x3d_mult_matrix(xform);

151 }

152

153 void x3d_scale(int32_t x, int32_t y, int32_t z)

154 {

155 int32_t m[] = ID_INIT;

156

157 m[0] = x;

158 m[5] = y;

159 m[10] = z;

160

161 x3d_mult_matrix(m);

162 }

163

164 void x3d_vertex_array(int count, const int32_t *ptr)

165 {

166 vertex_array = ptr;

167 vertex_count = count;

168 }

169

170 void x3d_color_array(int count, const int32_t *ptr)

171 {

172 color_array = ptr;

173 color_count = count;

174 }

175

176 void x3d_texcoord_array(int count, const int32_t *ptr)

177 {

178 texcoord_array = ptr;

179 texcoord_count = count;

180 }

181

182 int x3d_draw(int prim, int vnum)

183 {

184 int i, j, pverts = prim;

185 const int32_t *vptr = vertex_array;

186 const int32_t *cptr = color_array;

187 const int32_t *tptr = texcoord_array;

188 #ifndef PALMODE

189 short cr, cg, cb;

190 #endif

191 uint16_t color;

192

193 if(!vertex_array) return -1;

194

195 if(vnum > vertex_count) {

196 logmsg(LOG_DBG, "%s called with vnum=%d, but current vertex array has %d vertices\n",

197 __FUNCTION__, vnum, vertex_count);

198 vnum = vertex_count;

199 }

200 if(color_array && vnum > color_count) {

201 logmsg(LOG_DBG, "%s called with vnum=%d, but current color array has %d elements\n",

202 __FUNCTION__, vnum, color_count);

203 vnum = color_count;

204 }

205 if(texcoord_array && vnum > texcoord_count) {

206 logmsg(LOG_DBG, "%s called with vnum=%d, but current texcoord array has %d elements\n",

207 __FUNCTION__, vnum, texcoord_count);

208 vnum = texcoord_count;

209 }

210

211 for(i=0; i<vnum; i+=pverts) {

212 /* process vertices */

213 pvec3 vpos[4];

214 pvec3 col[4];

215 pvec2 tex[4];

216

217 for(j=0; j<pverts; j++) {

218 proc_vertex(vptr, cptr, tptr, vpos + j, col + j, tex + j);

219

220 if(vpos[j].z <= proj_near) {

221 goto skip_prim;

222 }

223

224 vptr += 3;

225 if(cptr) cptr += 3;

226 if(tptr) tptr += 2;

227 }

228

229 #ifdef PALMODE

230 color = im_color_index;

231 #else

232 cr = col[0].x >> 8;

233 cg = col[0].y >> 8;

234 cb = col[0].z >> 8;

235

236 if(cr > 255) cr = 255;

237 if(cg > 255) cg = 255;

238 if(cb > 255) cb = 255;

239

240 color = RGB(cr, cg, cb);

241 #endif

242

243 /* project & viewport */

244 for(j=0; j<pverts; j++) {

245 int32_t x, y;

246

247 x = x16mul(vpos[j].x, inv_tan_half_xfov);

248 x = x16div(x, vpos[j].z);

249 vpos[j].x = (x16mul(x, inv_proj_aspect) + 65536) * (WIDTH / 2);

250

251 y = x16mul(vpos[j].y, inv_tan_half_yfov);

252 y = x16div(y, vpos[j].z);

253 vpos[j].y = (65536 - y) * (HEIGHT / 2);

254 }

255

256 switch(pverts) {

257 case X3D_POINTS:

258 draw_point(vpos, color);

259 break;

260

261 case X3D_LINES:

262 break;

263

264 case X3D_TRIANGLES:

265 case X3D_QUADS:

266 draw_poly(pverts, vpos, tex, color, cur_tex >= 0 ? textures + cur_tex : 0);

267 if(dbg_fill_dump) {

268 dump_frame(back_buffer);

269 }

270 break;

271 }

272 skip_prim: ;

273 }

274

275 dbg_fill_dump = 0;

276 return 0;

277 }

278

279 static void proc_vertex(const int32_t *vin, const int32_t *cin, const int32_t *tin,

280 pvec3 *vout, pvec3 *cout, pvec2 *tout)

281 {

282 int i;

283 int32_t tvert[3];

284 int32_t *mvmat = mstack[mtop].m;

285

286 /* transform vertex with current matrix */

287 for(i=0; i<3; i++) {

288 tvert[i] = x16mul(mvmat[0], vin[0]) +

289 x16mul(mvmat[1], vin[1]) +

290 x16mul(mvmat[2], vin[2]) +

291 mvmat[3];

292 mvmat += 4;

293 }

294

295 vout->x = tvert[0];

296 vout->y = tvert[1];

297 vout->z = tvert[2];

298 /*logmsg(LOG_DBG, "%s: (%g %g %g) -> (%g %g %g)\n", __FUNCTION__,

299 x16tof(vin[0]), x16tof(vin[1]), x16tof(vin[2]),

300 x16tof(vout->x), x16tof(vout->y), x16tof(vout->z));*/

301

302 if(color_array) {

303 cout->x = cin[0];

304 cout->y = cin[1];

305 cout->z = cin[2];

306 } else {

307 cout->x = im_color[0];

308 cout->y = im_color[1];

309 cout->z = im_color[2];

310 }

311

312 if(texcoord_array) {

313 tout->x = tin[0];

314 tout->y = tin[1];

315 } else {

316 tout->x = im_texcoord[0];

317 tout->y = im_texcoord[1];

318 }

319 }

320

321 void x3d_color_index(int cidx)

322 {

323 im_color_index = cidx;

324 }

325

326 void x3d_color(int32_t r, int32_t g, int32_t b)

327 {

328 im_color[0] = r;

329 im_color[1] = g;

330 im_color[2] = b;

331 }

332

333 static int count_bits(int x)

334 {

335 int i, count = 0;

336 for(i=0; i<32; i++) {

337 if(x & 1) count++;

338 x >>= 1;

339 }

340 return count;

341 }

342

343 int x3d_create_texture_rgb(int xsz, int ysz, const uint16_t *pixels)

344 {

345 int i, j;

346

347 if(xsz == 0 || count_bits(xsz) > 1 || ysz == 0 || count_bits(ysz) > 1) {

348 logmsg(LOG_DBG, "%s: texture size (%dx%d) not power of two!\n", __func__, xsz, ysz);

349 return -1;

350 }

351

352 for(i=0; i<MAX_TEXTURES; i++) {

353 if(!textures[i].pixels) {

354 textures[i].pixels = pixels;

355 textures[i].xsz = xsz;

356 textures[i].ysz = ysz;

357 textures[i].umask = xsz - 1;

358 textures[i].vmask = ysz - 1;

359

360 for(j=0; j<32; j++) {

361 if((1 << j) == xsz) {

362 textures[i].ushift = j;

363 }

364 if((1 << j) == ysz) {

365 textures[i].vshift = j;

366 }

367 }

368

369 return i;

370 }

371 }

372 return -1;

373 }

374

375 void x3d_enable_texture(int texid)

376 {

377 cur_tex = texid;

378 }

379

380 void x3d_disable_texture(void)

381 {

382 cur_tex = 0;

383 }

384

385 int x3d_get_active_texture(void)

386 {

387 return cur_tex;

388 }

389

390 static int dump_frame(struct pixel_buffer *frame)

391 {

392 static int frameno;

393 char buf[128];

394 FILE *fp;

395 int i, npix;

396 uint16_t *ptr = frame->pixels;

397

398 sprintf(buf, "dump%03d.ppm", ++frameno);

399

400 if(!(fp = fopen(buf, "wb"))) {

401 fprintf(stderr, "failed to dump file: %s\n", buf);

402 return -1;

403 }

404

405 fprintf(fp, "P6\n%d %d\n255\n", frame->x, frame->y);

406

407 npix = frame->x * frame->y;

408 for(i=0; i<npix; i++) {

409 uint16_t pixel = *ptr++;

410 fputc(GET_R(pixel), fp);

411 fputc(GET_G(pixel), fp);

412 fputc(GET_B(pixel), fp);

413 }

414 fclose(fp);

415 return 0;

416 }