15 typedef float g3d_matrix[16];
19 #define IMM_VBUF_SIZE 256
37 g3d_matrix mat[G3D_NUM_MATRICES][STACK_SIZE];
38 int mtop[G3D_NUM_MATRICES];
44 struct light lt[MAX_LIGHTS];
54 int imm_numv, imm_pcount;
55 struct g3d_vertex imm_curv;
56 struct g3d_vertex imm_vbuf[IMM_VBUF_SIZE];
59 static void imm_flush(void);
60 static void xform4_vec3(const float *mat, float *vec);
61 static void xform3_vec3(const float *mat, float *vec);
62 static void shade(struct g3d_vertex *v);
64 static struct g3d_state *st;
65 static const float idmat[] = {
76 if(!(st = calloc(1, sizeof *st))) {
77 fprintf(stderr, "failed to allocate G3D context\n");
80 st->fill_mode = POLYFILL_FLAT;
82 for(i=0; i<G3D_NUM_MATRICES; i++) {
87 for(i=0; i<MAX_LIGHTS; i++) {
88 g3d_light_color(i, 1, 1, 1);
90 g3d_light_ambient(0.1, 0.1, 0.1);
92 g3d_mtl_diffuse(1, 1, 1);
96 void g3d_destroy(void)
101 void g3d_framebuffer(int width, int height, void *pixels)
107 pfill_fb.pixels = pixels;
108 pfill_fb.width = width;
109 pfill_fb.height = height;
111 g3d_viewport(0, 0, width, height);
114 void g3d_viewport(int x, int y, int w, int h)
122 void g3d_enable(unsigned int opt)
127 void g3d_disable(unsigned int opt)
132 void g3d_setopt(unsigned int opt, unsigned int mask)
134 st->opt = (st->opt & ~mask) | (opt & mask);
137 unsigned int g3d_getopt(unsigned int mask)
139 return st->opt & mask;
142 void g3d_front_face(unsigned int order)
144 st->frontface = order;
147 void g3d_polygon_mode(int pmode)
149 st->fill_mode = pmode;
152 void g3d_matrix_mode(int mmode)
157 void g3d_load_identity(void)
159 int top = st->mtop[st->mmode];
160 memcpy(st->mat[st->mmode][top], idmat, 16 * sizeof(float));
163 void g3d_load_matrix(const float *m)
165 int top = st->mtop[st->mmode];
166 memcpy(st->mat[st->mmode][top], m, 16 * sizeof(float));
169 #define M(i,j) (((i) << 2) + (j))
170 void g3d_mult_matrix(const float *m2)
172 int i, j, top = st->mtop[st->mmode];
174 float *dest = st->mat[st->mmode][top];
176 memcpy(m1, dest, sizeof m1);
180 *dest++ = m1[M(0,j)] * m2[M(i,0)] +
181 m1[M(1,j)] * m2[M(i,1)] +
182 m1[M(2,j)] * m2[M(i,2)] +
183 m1[M(3,j)] * m2[M(i,3)];
188 void g3d_push_matrix(void)
190 int top = st->mtop[st->mmode];
191 if(top >= G3D_NUM_MATRICES) {
192 fprintf(stderr, "g3d_push_matrix overflow\n");
195 memcpy(st->mat[st->mmode][top + 1], st->mat[st->mmode][top], 16 * sizeof(float));
196 st->mtop[st->mmode] = top + 1;
199 void g3d_pop_matrix(void)
201 if(st->mtop[st->mmode] <= 0) {
202 fprintf(stderr, "g3d_pop_matrix underflow\n");
205 --st->mtop[st->mmode];
208 void g3d_translate(float x, float y, float z)
210 float m[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
217 void g3d_rotate(float deg, float x, float y, float z)
219 float m[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
221 float angle = M_PI * deg / 180.0f;
222 float sina = sin(angle);
223 float cosa = cos(angle);
224 float one_minus_cosa = 1.0f - cosa;
229 m[0] = nxsq + (1.0f - nxsq) * cosa;
230 m[4] = x * y * one_minus_cosa - z * sina;
231 m[8] = x * z * one_minus_cosa + y * sina;
232 m[1] = x * y * one_minus_cosa + z * sina;
233 m[5] = nysq + (1.0 - nysq) * cosa;
234 m[9] = y * z * one_minus_cosa - x * sina;
235 m[2] = x * z * one_minus_cosa - y * sina;
236 m[6] = y * z * one_minus_cosa + x * sina;
237 m[10] = nzsq + (1.0 - nzsq) * cosa;
243 void g3d_scale(float x, float y, float z)
245 float m[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
253 void g3d_ortho(float left, float right, float bottom, float top, float znear, float zfar)
255 float m[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
257 float dx = right - left;
258 float dy = top - bottom;
259 float dz = zfar - znear;
264 m[12] = -(right + left) / dx;
265 m[13] = -(top + bottom) / dy;
266 m[14] = -(zfar + znear) / dz;
271 void g3d_frustum(float left, float right, float bottom, float top, float nr, float fr)
273 float m[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
275 float dx = right - left;
276 float dy = top - bottom;
279 float a = (right + left) / dx;
280 float b = (top + bottom) / dy;
281 float c = -(fr + nr) / dz;
282 float d = -2.0 * fr * nr / dz;
284 m[0] = 2.0 * nr / dx;
285 m[5] = 2.0 * nr / dy;
295 void g3d_perspective(float vfov_deg, float aspect, float znear, float zfar)
297 float m[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
299 float vfov = M_PI * vfov_deg / 180.0f;
300 float s = 1.0f / tan(vfov * 0.5f);
301 float range = znear - zfar;
305 m[10] = (znear + zfar) / range;
307 m[14] = 2.0f * znear * zfar / range;
312 const float *g3d_get_matrix(int which, float *m)
314 int top = st->mtop[which];
317 memcpy(m, st->mat[which][top], 16 * sizeof(float));
319 return st->mat[which][top];
322 void g3d_light_pos(int idx, float x, float y, float z)
324 int mvtop = st->mtop[G3D_MODELVIEW];
330 xform4_vec3(st->mat[G3D_MODELVIEW][mvtop], &st->lt[idx].x);
333 void g3d_light_color(int idx, float r, float g, float b)
340 void g3d_light_ambient(float r, float g, float b)
347 void g3d_mtl_diffuse(float r, float g, float b)
354 void g3d_mtl_specular(float r, float g, float b)
361 void g3d_mtl_shininess(float shin)
366 static INLINE int calc_shift(unsigned int x)
376 static INLINE int calc_mask(unsigned int x)
381 void g3d_set_texture(int xsz, int ysz, void *pixels)
383 pfill_tex.pixels = pixels;
384 pfill_tex.width = xsz;
385 pfill_tex.height = ysz;
387 pfill_tex.xshift = calc_shift(xsz);
388 pfill_tex.yshift = calc_shift(ysz);
389 pfill_tex.xmask = calc_mask(xsz);
390 pfill_tex.ymask = calc_mask(ysz);
393 void g3d_draw(int prim, const struct g3d_vertex *varr, int varr_size)
395 g3d_draw_indexed(prim, varr, varr_size, 0, 0);
398 void g3d_draw_indexed(int prim, const struct g3d_vertex *varr, int varr_size,
399 const int16_t *iarr, int iarr_size)
402 struct pvertex pv[16];
403 struct g3d_vertex v[16];
404 int vnum = prim; /* primitive vertex counts correspond to enum values */
405 int mvtop = st->mtop[G3D_MODELVIEW];
406 int ptop = st->mtop[G3D_PROJECTION];
408 /* calc the normal matrix */
409 memcpy(st->norm_mat, st->mat[G3D_MODELVIEW][mvtop], 16 * sizeof(float));
410 st->norm_mat[12] = st->norm_mat[13] = st->norm_mat[14] = 0.0f;
412 nfaces = (iarr ? iarr_size : varr_size) / vnum;
414 for(j=0; j<nfaces; j++) {
415 vnum = prim; /* reset vnum for each iteration */
417 for(i=0; i<vnum; i++) {
418 v[i] = iarr ? varr[*iarr++] : *varr++;
420 xform4_vec3(st->mat[G3D_MODELVIEW][mvtop], &v[i].x);
421 xform3_vec3(st->norm_mat, &v[i].nx);
423 if(st->opt & G3D_LIGHTING) {
426 xform4_vec3(st->mat[G3D_PROJECTION][ptop], &v[i].x);
431 struct g3d_vertex tmpv[16];
432 memcpy(tmpv, v, vnum * sizeof *v);
434 if(clip_frustum(v, &vnum, tmpv, vnum, i) < 0) {
435 /* polygon completely outside of view volume. discard */
443 for(i=0; i<vnum; i++) {
447 /*v[i].z /= v[i].w;*/
450 /* viewport transformation */
451 v[i].x = (v[i].x * 0.5f + 0.5f) * (float)st->vport[2] + st->vport[0];
452 v[i].y = (0.5f - v[i].y * 0.5f) * (float)st->vport[3] + st->vport[1];
454 /* convert pos to 24.8 fixed point */
455 pv[i].x = cround64(v[i].x * 256.0f);
456 pv[i].y = cround64(v[i].y * 256.0f);
457 /* convert tex coords to 16.16 fixed point */
458 pv[i].u = cround64(v[i].u * 65536.0f);
459 pv[i].v = cround64(v[i].v * 65536.0f);
460 /* pass the color through as is */
467 /* backface culling */
468 if(vnum > 2 && st->opt & G3D_CULL_FACE) {
469 int32_t ax = pv[1].x - pv[0].x;
470 int32_t ay = pv[1].y - pv[0].y;
471 int32_t bx = pv[2].x - pv[0].x;
472 int32_t by = pv[2].y - pv[0].y;
473 int32_t cross_z = ax * (by >> 8) - ay * (bx >> 8);
474 int sign = (cross_z >> 31) & 1;
476 if(!(sign ^ st->frontface)) {
477 continue; /* back-facing */
483 if(st->opt & G3D_BLEND) {
485 int inv_alpha = 255 - pv[0].a;
486 uint16_t *dest = st->pixels + (pv[0].y >> 8) * st->width + (pv[0].x >> 8);
487 r = ((int)pv[0].r * pv[0].a + UNPACK_R16(*dest) * inv_alpha) >> 8;
488 g = ((int)pv[0].g * pv[0].a + UNPACK_G16(*dest) * inv_alpha) >> 8;
489 b = ((int)pv[0].b * pv[0].a + UNPACK_B16(*dest) * inv_alpha) >> 8;
490 *dest++ = PACK_RGB16(r, g, b);
492 uint16_t *dest = st->pixels + (pv[0].y >> 8) * st->width + (pv[0].x >> 8);
493 *dest = PACK_RGB16(pv[0].r, pv[0].g, pv[0].b);
498 /* TODO: draw line */
502 polyfill(st->fill_mode, pv, vnum);
507 void g3d_begin(int prim)
510 st->imm_pcount = prim;
519 static void imm_flush(void)
521 int numv = st->imm_numv;
523 g3d_draw_indexed(st->imm_prim, st->imm_vbuf, numv, 0, 0);
526 void g3d_vertex(float x, float y, float z)
528 struct g3d_vertex *vptr = st->imm_vbuf + st->imm_numv++;
529 *vptr = st->imm_curv;
535 if(!--st->imm_pcount) {
536 if(st->imm_numv >= IMM_VBUF_SIZE - st->imm_prim) {
539 st->imm_pcount = st->imm_prim;
543 void g3d_normal(float x, float y, float z)
550 void g3d_color3b(unsigned char r, unsigned char g, unsigned char b)
555 st->imm_curv.a = 255;
558 void g3d_color4b(unsigned char r, unsigned char g, unsigned char b, unsigned char a)
566 void g3d_color3f(float r, float g, float b)
571 st->imm_curv.r = ir > 255 ? 255 : ir;
572 st->imm_curv.g = ig > 255 ? 255 : ig;
573 st->imm_curv.b = ib > 255 ? 255 : ib;
574 st->imm_curv.a = 255;
577 void g3d_color4f(float r, float g, float b, float a)
583 st->imm_curv.r = ir > 255 ? 255 : ir;
584 st->imm_curv.g = ig > 255 ? 255 : ig;
585 st->imm_curv.b = ib > 255 ? 255 : ib;
586 st->imm_curv.a = ia > 255 ? 255 : ia;
589 void g3d_texcoord(float u, float v)
595 static void xform4_vec3(const float *mat, float *vec)
597 float x = mat[0] * vec[0] + mat[4] * vec[1] + mat[8] * vec[2] + mat[12];
598 float y = mat[1] * vec[0] + mat[5] * vec[1] + mat[9] * vec[2] + mat[13];
599 float z = mat[2] * vec[0] + mat[6] * vec[1] + mat[10] * vec[2] + mat[14];
600 float w = mat[3] * vec[0] + mat[7] * vec[1] + mat[11] * vec[2] + mat[15];
608 static void xform3_vec3(const float *mat, float *vec)
610 float x = mat[0] * vec[0] + mat[4] * vec[1] + mat[8] * vec[2];
611 float y = mat[1] * vec[0] + mat[5] * vec[1] + mat[9] * vec[2];
612 float z = mat[2] * vec[0] + mat[6] * vec[1] + mat[10] * vec[2];
619 #define NORMALIZE(v) \
621 float len = sqrt(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]); \
623 float s = 1.0 / len; \
630 static void shade(struct g3d_vertex *v)
635 color[0] = st->ambient[0] * st->mtl.kd[0];
636 color[1] = st->ambient[1] * st->mtl.kd[1];
637 color[2] = st->ambient[2] * st->mtl.kd[2];
639 for(i=0; i<MAX_LIGHTS; i++) {
643 if(!(st->opt & (G3D_LIGHT0 << i))) {
647 ldir[0] = st->lt[i].x - v->x;
648 ldir[1] = st->lt[i].y - v->y;
649 ldir[2] = st->lt[i].z - v->z;
652 if((ndotl = v->nx * ldir[0] + v->ny * ldir[1] + v->nz * ldir[2]) < 0.0f) {
656 color[0] += st->mtl.kd[0] * st->lt[i].r * ndotl;
657 color[1] += st->mtl.kd[1] * st->lt[i].g * ndotl;
658 color[2] += st->mtl.kd[2] * st->lt[i].b * ndotl;
661 r = cround64(color[0] * 255.0);
662 g = cround64(color[1] * 255.0);
663 b = cround64(color[2] * 255.0);
665 v->r = r > 255 ? 255 : r;
666 v->g = g > 255 ? 255 : g;
667 v->b = b > 255 ? 255 : b;