X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=dosdemo;a=blobdiff_plain;f=src%2F3dgfx.c;h=49b4c2c2c413b8ca34f91883681d5553a0983a40;hp=5cf3c42645df36c9364daa8bbbbce4fba757ae91;hb=633743214adddf6ec20f8b1bee1782e6966023af;hpb=d1a2007e191d68b104e436d1817eafcc99ae21dd diff --git a/src/3dgfx.c b/src/3dgfx.c index 5cf3c42..49b4c2c 100644 --- a/src/3dgfx.c +++ b/src/3dgfx.c @@ -1,17 +1,26 @@ #include -#include +#include #include +#include +#include #include "3dgfx.h" #include "polyfill.h" +#include "inttypes.h" #define STACK_SIZE 8 typedef float g3d_matrix[16]; +#define MAX_VBUF_SIZE 256 + struct g3d_state { unsigned int opt; + int frontface; g3d_matrix mat[G3D_NUM_MATRICES][STACK_SIZE]; int mtop[G3D_NUM_MATRICES]; + int mmode; + + g3d_matrix norm_mat; int width, height; void *pixels; @@ -19,9 +28,9 @@ struct g3d_state { static void xform4_vec3(const float *mat, float *vec); static void xform3_vec3(const float *mat, float *vec); -static void proc_vertex(struct pvertex *res, const struct g3d_vertex *vert, int space); +static void shade(struct g3d_vertex *v); -static struct g3d_state st; +static struct g3d_state *st; static const float idmat[] = { 1, 0, 0, 0, 0, 1, 0, 0, @@ -29,58 +38,82 @@ static const float idmat[] = { 0, 0, 0, 1 }; -void g3d_init(void) +int g3d_init(void) { int i; - memset(&st, 0, sizeof st); + if(!(st = calloc(1, sizeof *st))) { + fprintf(stderr, "failed to allocate G3D context\n"); + return -1; + } for(i=0; iwidth = width; + st->height = height; + st->pixels = pixels; } void g3d_enable(unsigned int opt) { - st.opt |= opt; + st->opt |= opt; } void g3d_disable(unsigned int opt) { - st.opt &= ~opt; + st->opt &= ~opt; } void g3d_setopt(unsigned int opt, unsigned int mask) { - st.opt = (st.opt & ~mask) | (opt & mask); + st->opt = (st->opt & ~mask) | (opt & mask); } unsigned int g3d_getopt(unsigned int mask) { - return st.opt & mask; + return st->opt & mask; } -void g3d_set_matrix(int which, const float *m) +void g3d_front_face(unsigned int order) { - int top = st.mtop[which]; + st->frontface = order; +} - if(!m) m = idmat; - memcpy(st.mat[which][top], m, 16 * sizeof(float)); +void g3d_matrix_mode(int mmode) +{ + st->mmode = mmode; +} + +void g3d_load_identity(void) +{ + int top = st->mtop[st->mmode]; + memcpy(st->mat[st->mmode][top], idmat, 16 * sizeof(float)); +} + +void g3d_load_matrix(const float *m) +{ + int top = st->mtop[st->mmode]; + memcpy(st->mat[st->mmode][top], m, 16 * sizeof(float)); } #define M(i,j) (((i) << 2) + (j)) -void g3d_mult_matrix(int which, const float *m2) +void g3d_mult_matrix(const float *m2) { - int i, j, top = st.mtop[which]; + int i, j, top = st->mtop[st->mmode]; float m1[16]; - float *dest = st.mat[which][top]; + float *dest = st->mat[st->mmode][top]; memcpy(m1, dest, sizeof m1); @@ -94,36 +127,36 @@ void g3d_mult_matrix(int which, const float *m2) } } -void g3d_push_matrix(int which) +void g3d_push_matrix(void) { - int top = st.mtop[which]; + int top = st->mtop[st->mmode]; if(top >= G3D_NUM_MATRICES) { fprintf(stderr, "g3d_push_matrix overflow\n"); return; } - memcpy(st.mat[which][top + 1], st.mat[which][top], 16 * sizeof(float)); - st.mtop[which] = top + 1;; + memcpy(st->mat[st->mmode][top + 1], st->mat[st->mmode][top], 16 * sizeof(float)); + st->mtop[st->mmode] = top + 1; } -void g3d_pop_matrix(int which) +void g3d_pop_matrix(void) { - if(st.mtop[which] <= 0) { + if(st->mtop[st->mmode] <= 0) { fprintf(stderr, "g3d_pop_matrix underflow\n"); return; } - --st.mtop[which]; + --st->mtop[st->mmode]; } -void g3d_translate(int which, float x, float y, float z) +void g3d_translate(float x, float y, float z) { float m[] = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1}; m[12] = x; m[13] = y; m[14] = z; - g3d_mult_matrix(which, m); + g3d_mult_matrix(m); } -void g3d_rotate(int which, float deg, float x, float y, float z) +void g3d_rotate(float deg, float x, float y, float z) { float m[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; @@ -144,20 +177,22 @@ void g3d_rotate(int which, float deg, float x, float y, float z) m[2] = x * z * one_minus_cosa - y * sina; m[6] = y * z * one_minus_cosa + x * sina; m[10] = nzsq + (1.0 - nzsq) * cosa; + m[15] = 1.0f; - g3d_mult_matrix(which, m); + g3d_mult_matrix(m); } -void g3d_scale(int which, float x, float y, float z) +void g3d_scale(float x, float y, float z) { float m[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; m[0] = x; m[5] = y; m[10] = z; - g3d_mult_matrix(which, m); + m[15] = 1.0f; + g3d_mult_matrix(m); } -void g3d_ortho(int which, float left, float right, float bottom, float top, float znear, float zfar) +void g3d_ortho(float left, float right, float bottom, float top, float znear, float zfar) { float m[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; @@ -172,10 +207,10 @@ void g3d_ortho(int which, float left, float right, float bottom, float top, floa m[13] = -(top + bottom) / dy; m[14] = -(zfar + znear) / dz; - g3d_mult_matrix(which, m); + g3d_mult_matrix(m); } -void g3d_frustum(int which, float left, float right, float bottom, float top, float nr, float fr) +void g3d_frustum(float left, float right, float bottom, float top, float nr, float fr) { float m[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; @@ -196,10 +231,10 @@ void g3d_frustum(int which, float left, float right, float bottom, float top, fl m[11] = -1.0f; m[14] = d; - g3d_mult_matrix(which, m); + g3d_mult_matrix(m); } -void g3d_perspective(int which, float vfov_deg, float aspect, float znear, float zfar) +void g3d_perspective(float vfov_deg, float aspect, float znear, float zfar) { float m[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; @@ -213,24 +248,84 @@ void g3d_perspective(int which, float vfov_deg, float aspect, float znear, float m[11] = -1.0f; m[14] = 2.0f * znear * zfar / range; - g3d_mult_matrix(which, m); + g3d_mult_matrix(m); } -void g3d_draw(int prim, int space, const struct g3d_vertex *varr, int varr_size) +#define CROSS(res, a, b) \ + do { \ + (res)[0] = (a)[1] * (b)[2] - (a)[2] * (b)[1]; \ + (res)[1] = (a)[2] * (b)[0] - (a)[0] * (b)[2]; \ + (res)[2] = (a)[0] * (b)[1] - (a)[1] * (b)[0]; \ + } while(0) + +void g3d_draw(int prim, const struct g3d_vertex *varr, int varr_size) { int i; - int vnum = prim; /* primitive vertex counts correspond to the enum values */ + struct pvertex pv[4]; + struct g3d_vertex v[4]; + int vnum = prim; /* primitive vertex counts correspond to enum values */ + int mvtop = st->mtop[G3D_MODELVIEW]; + int ptop = st->mtop[G3D_PROJECTION]; + + /* calc the normal matrix */ + memcpy(st->norm_mat, st->mat[G3D_MODELVIEW][mvtop], 16 * sizeof(float)); + st->norm_mat[12] = st->norm_mat[13] = st->norm_mat[14] = 0.0f; while(varr_size >= vnum) { - struct pvertex pv[4]; + varr_size -= vnum; for(i=0; imat[G3D_MODELVIEW][mvtop], &v[i].x); + xform3_vec3(st->norm_mat, &v[i].nx); + + if(st->opt & G3D_LIGHTING) { + shade(v + i); + } + xform4_vec3(st->mat[G3D_PROJECTION][ptop], &v[i].x); } - polyfill_wire(pv, vnum); + /* TODO clipping */ - varr_size -= vnum; + for(i=0; iwidth; + v[i].y = (0.5f - v[i].y * 0.5f) * (float)st->height; + + /* convert pos to 24.8 fixed point */ + pv[i].x = (int32_t)(v[i].x * 256.0f); + pv[i].y = (int32_t)(v[i].y * 256.0f); + /* convert tex coords to 16.16 fixed point */ + pv[i].u = (int32_t)(v[i].u * 65536.0f); + pv[i].v = (int32_t)(v[i].v * 65536.0f); + /* pass the color through as is */ + pv[i].r = v[i].r; + pv[i].g = v[i].g; + pv[i].b = v[i].b; + } + + /* backface culling */ + if(vnum > 2 && st->opt & G3D_CULL_FACE) { + int32_t ax = pv[1].x - pv[0].x; + int32_t ay = pv[1].y - pv[0].y; + int32_t bx = pv[2].x - pv[0].x; + int32_t by = pv[2].y - pv[0].y; + int32_t cross_z = ax * (by >> 8) - ay * (bx >> 8); + int sign = (cross_z >> 31) & 1; + + if(!(sign ^ st->frontface)) { + continue; /* back-facing */ + } + } + + polyfill_flat(pv, vnum); } } @@ -258,64 +353,7 @@ static void xform3_vec3(const float *mat, float *vec) vec[2] = z; } -#define VEC3(v, x, y, z) do { v[0] = x; v[1] = y; v[2] = z; } while(0) -#define VEC4(v, x, y, z, w) do { v[0] = x; v[1] = y; v[2] = z; v[3] = w; } while(0) - -static void proc_vertex(struct pvertex *res, const struct g3d_vertex *vert, int space) +static void shade(struct g3d_vertex *v) { - float pos[4]; - float norm[3]; - float color[3]; - int mvtop = st.mtop[G3D_MODELVIEW]; - int ptop = st.mtop[G3D_PROJECTION]; - g3d_matrix norm_mat; - - VEC4(pos, vert->x, vert->y, vert->z, 1.0f); - VEC3(norm, vert->nx, vert->ny, vert->nz); - - switch(space) { - case G3D_LOCAL_SPACE: - memcpy(norm_mat, st.mat[G3D_MODELVIEW][mvtop], 16 * sizeof(float)); - norm_mat[12] = norm_mat[13] = norm_mat[14] = 0.0f; - - xform4_vec3(pos, st.mat[G3D_MODELVIEW][mvtop]); - xform3_vec3(norm, norm_mat); - - case G3D_VIEW_SPACE: - if(st.opt & G3D_LIGHTING) { - /* TODO lighting */ - color[0] = vert->r; - color[1] = vert->g; - color[2] = vert->b; - } - xform4_vec3(pos, st.mat[G3D_PROJECTION][ptop]); - - case G3D_CLIP_SPACE: - /* TODO clipping */ - if(pos[3] != 0.0f) { - pos[0] /= pos[3]; - pos[1] /= pos[3]; - pos[2] /= pos[3]; - } - - case G3D_SCREEN_SPACE: - pos[0] = (pos[0] * 0.5 + 0.5) * (float)st.width; - pos[1] = (0.5 - pos[0] * 0.5) * (float)st.height; - - case G3D_PIXEL_SPACE: - break; - } - - /* convert pos to 24.8 fixed point */ - res->x = (int32_t)(pos[0] * 256.0f); - res->y = (int32_t)(pos[1] * 256.0f); - - /* convert tex coords to 16.16 fixed point */ - res->u = (int32_t)(vert->u * 65536.0f); - res->v = (int32_t)(vert->v * 65536.0f); - - /* pass color through as is */ - res->r = color[0]; - res->g = color[1]; - res->b = color[2]; + v->r = v->g = v->b = 255; }