+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <assert.h>
+#if defined(__WATCOMC__) || defined(_MSC_VER) || defined(__DJGPP__)
+#include <malloc.h>
+#else
+#include <alloca.h>
+#endif
+#include "3dgfx.h"
+#include "gfxutil.h"
+#include "polyfill.h"
+#include "polyclip.h"
+#include "inttypes.h"
+#include "census.h"
+#include "util.h"
+
+#define STACK_SIZE 8
+typedef float g3d_matrix[16];
+
+#define MAX_LIGHTS 4
+
+#define IMM_VBUF_SIZE 256
+
+struct light {
+ float x, y, z;
+ float r, g, b;
+};
+
+struct material {
+ float kd[3];
+ float ks[3];
+ float shin;
+};
+
+struct g3d_state {
+ unsigned int opt;
+ int frontface;
+ int polymode;
+
+ g3d_matrix mat[G3D_NUM_MATRICES][STACK_SIZE];
+ int mtop[G3D_NUM_MATRICES];
+ int mmode;
+
+ g3d_matrix norm_mat;
+
+ float ambient[3];
+ struct light lt[MAX_LIGHTS];
+ struct material mtl;
+
+ int width, height;
+ uint32_t *pixels;
+
+ int vport[4];
+
+ /* immediate mode */
+ int imm_prim;
+ int imm_numv, imm_pcount;
+ struct g3d_vertex imm_curv;
+ struct g3d_vertex imm_vbuf[IMM_VBUF_SIZE];
+};
+
+static void imm_flush(void);
+static void xform4_vec3(const float *mat, float *vec);
+static void xform3_vec3(const float *mat, float *vec);
+static void shade(struct g3d_vertex *v);
+
+static struct g3d_state *st;
+static const float idmat[] = {
+ 1, 0, 0, 0,
+ 0, 1, 0, 0,
+ 0, 0, 1, 0,
+ 0, 0, 0, 1
+};
+
+int g3d_init(void)
+{
+ int i;
+
+ if(!(st = calloc(1, sizeof *st))) {
+ fprintf(stderr, "failed to allocate G3D context\n");
+ return -1;
+ }
+ st->opt = G3D_CLIP_FRUSTUM;
+ st->polymode = POLYFILL_FLAT;
+
+ for(i=0; i<G3D_NUM_MATRICES; i++) {
+ g3d_matrix_mode(i);
+ g3d_load_identity();
+ }
+
+ for(i=0; i<MAX_LIGHTS; i++) {
+ g3d_light_color(i, 1, 1, 1);
+ }
+ g3d_light_ambient(0.1, 0.1, 0.1);
+
+ g3d_mtl_diffuse(1, 1, 1);
+ return 0;
+}
+
+void g3d_destroy(void)
+{
+ free(st);
+}
+
+void g3d_framebuffer(int width, int height, void *pixels)
+{
+ st->width = width;
+ st->height = height;
+ st->pixels = pixels;
+
+ pfill_fb.pixels = pixels;
+ pfill_fb.width = width;
+ pfill_fb.height = height;
+
+ g3d_viewport(0, 0, width, height);
+}
+
+/* set the framebuffer pointer, without resetting the size */
+void g3d_framebuffer_addr(void *pixels)
+{
+ st->pixels = pixels;
+ pfill_fb.pixels = pixels;
+}
+
+void g3d_viewport(int x, int y, int w, int h)
+{
+ st->vport[0] = x;
+ st->vport[1] = y;
+ st->vport[2] = w;
+ st->vport[3] = h;
+}
+
+void g3d_enable(unsigned int opt)
+{
+ st->opt |= opt;
+}
+
+void g3d_disable(unsigned int opt)
+{
+ st->opt &= ~opt;
+}
+
+void g3d_setopt(unsigned int opt, unsigned int mask)
+{
+ st->opt = (st->opt & ~mask) | (opt & mask);
+}
+
+unsigned int g3d_getopt(unsigned int mask)
+{
+ return st->opt & mask;
+}
+
+void g3d_front_face(unsigned int order)
+{
+ st->frontface = order;
+}
+
+void g3d_polygon_mode(int pmode)
+{
+ st->polymode = pmode;
+}
+
+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(const float *m2)
+{
+ int i, j, top = st->mtop[st->mmode];
+ float m1[16];
+ float *dest = st->mat[st->mmode][top];
+
+ memcpy(m1, dest, sizeof m1);
+
+ for(i=0; i<4; i++) {
+ for(j=0; j<4; j++) {
+ *dest++ = m1[M(0,j)] * m2[M(i,0)] +
+ m1[M(1,j)] * m2[M(i,1)] +
+ m1[M(2,j)] * m2[M(i,2)] +
+ m1[M(3,j)] * m2[M(i,3)];
+ }
+ }
+}
+
+void g3d_push_matrix(void)
+{
+ int top = st->mtop[st->mmode];
+ if(top >= G3D_NUM_MATRICES) {
+ fprintf(stderr, "g3d_push_matrix overflow\n");
+ return;
+ }
+ 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(void)
+{
+ if(st->mtop[st->mmode] <= 0) {
+ fprintf(stderr, "g3d_pop_matrix underflow\n");
+ return;
+ }
+ --st->mtop[st->mmode];
+}
+
+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(m);
+}
+
+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};
+
+ float angle = M_PI * deg / 180.0f;
+ float sina = sin(angle);
+ float cosa = cos(angle);
+ float one_minus_cosa = 1.0f - cosa;
+ float nxsq = x * x;
+ float nysq = y * y;
+ float nzsq = z * z;
+
+ m[0] = nxsq + (1.0f - nxsq) * cosa;
+ m[4] = x * y * one_minus_cosa - z * sina;
+ m[8] = x * z * one_minus_cosa + y * sina;
+ m[1] = x * y * one_minus_cosa + z * sina;
+ m[5] = nysq + (1.0 - nysq) * cosa;
+ m[9] = y * z * one_minus_cosa - x * sina;
+ 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(m);
+}
+
+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;
+ m[15] = 1.0f;
+ g3d_mult_matrix(m);
+}
+
+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};
+
+ float dx = right - left;
+ float dy = top - bottom;
+ float dz = zfar - znear;
+
+ m[0] = 2.0 / dx;
+ m[5] = 2.0 / dy;
+ m[10] = -2.0 / dz;
+ m[12] = -(right + left) / dx;
+ m[13] = -(top + bottom) / dy;
+ m[14] = -(zfar + znear) / dz;
+
+ g3d_mult_matrix(m);
+}
+
+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};
+
+ float dx = right - left;
+ float dy = top - bottom;
+ float dz = fr - nr;
+
+ float a = (right + left) / dx;
+ float b = (top + bottom) / dy;
+ float c = -(fr + nr) / dz;
+ float d = -2.0 * fr * nr / dz;
+
+ m[0] = 2.0 * nr / dx;
+ m[5] = 2.0 * nr / dy;
+ m[8] = a;
+ m[9] = b;
+ m[10] = c;
+ m[11] = -1.0f;
+ m[14] = d;
+
+ g3d_mult_matrix(m);
+}
+
+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};
+
+ float vfov = M_PI * vfov_deg / 180.0f;
+ float s = 1.0f / tan(vfov * 0.5f);
+ float range = znear - zfar;
+
+ m[0] = s / aspect;
+ m[5] = s;
+ m[10] = (znear + zfar) / range;
+ m[11] = -1.0f;
+ m[14] = 2.0f * znear * zfar / range;
+
+ g3d_mult_matrix(m);
+}
+
+const float *g3d_get_matrix(int which, float *m)
+{
+ int top = st->mtop[which];
+
+ if(m) {
+ memcpy(m, st->mat[which][top], 16 * sizeof(float));
+ }
+ return st->mat[which][top];
+}
+
+void g3d_light_pos(int idx, float x, float y, float z)
+{
+ int mvtop = st->mtop[G3D_MODELVIEW];
+
+ st->lt[idx].x = x;
+ st->lt[idx].y = y;
+ st->lt[idx].z = z;
+
+ xform4_vec3(st->mat[G3D_MODELVIEW][mvtop], &st->lt[idx].x);
+}
+
+void g3d_light_color(int idx, float r, float g, float b)
+{
+ st->lt[idx].r = r;
+ st->lt[idx].g = g;
+ st->lt[idx].b = b;
+}
+
+void g3d_light_ambient(float r, float g, float b)
+{
+ st->ambient[0] = r;
+ st->ambient[1] = g;
+ st->ambient[2] = b;
+}
+
+void g3d_mtl_diffuse(float r, float g, float b)
+{
+ st->mtl.kd[0] = r;
+ st->mtl.kd[1] = g;
+ st->mtl.kd[2] = b;
+}
+
+void g3d_mtl_specular(float r, float g, float b)
+{
+ st->mtl.ks[0] = r;
+ st->mtl.ks[1] = g;
+ st->mtl.ks[2] = b;
+}
+
+void g3d_mtl_shininess(float shin)
+{
+ st->mtl.shin = shin;
+}
+
+static INLINE int calc_shift(unsigned int x)
+{
+ int res = -1;
+ while(x) {
+ x >>= 1;
+ ++res;
+ }
+ return res;
+}
+
+static INLINE int calc_mask(unsigned int x)
+{
+ return x - 1;
+}
+
+void g3d_set_texture(int xsz, int ysz, void *pixels)
+{
+ pfill_tex.pixels = pixels;
+ pfill_tex.width = xsz;
+ pfill_tex.height = ysz;
+
+ pfill_tex.xshift = calc_shift(xsz);
+ pfill_tex.yshift = calc_shift(ysz);
+ pfill_tex.xmask = calc_mask(xsz);
+ pfill_tex.ymask = calc_mask(ysz);
+}
+
+void g3d_draw(int prim, const struct g3d_vertex *varr, int varr_size)
+{
+ g3d_draw_indexed(prim, varr, varr_size, 0, 0);
+}
+
+void g3d_draw_indexed(int prim, const struct g3d_vertex *varr, int varr_size,
+ const uint16_t *iarr, int iarr_size)
+{
+ int i, j, vnum, nfaces, fill_mode;
+ struct pvertex pv[16];
+ struct g3d_vertex v[16];
+ int mvtop = st->mtop[G3D_MODELVIEW];
+ int ptop = st->mtop[G3D_PROJECTION];
+ struct g3d_vertex *tmpv;
+
+ tmpv = alloca(prim * 6 * sizeof *tmpv);
+
+ /* 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;
+
+ nfaces = (iarr ? iarr_size : varr_size) / prim;
+
+ for(j=0; j<nfaces; j++) {
+ vnum = prim; /* reset vnum for each iteration */
+
+ for(i=0; i<vnum; i++) {
+ v[i] = iarr ? varr[*iarr++] : *varr++;
+
+ xform4_vec3(st->mat[G3D_MODELVIEW][mvtop], &v[i].x);
+ xform3_vec3(st->norm_mat, &v[i].nx);
+
+ if(st->opt & G3D_LIGHTING) {
+ shade(v + i);
+ }
+ if(st->opt & G3D_TEXTURE_GEN) {
+ v[i].u = v[i].nx * 0.5 + 0.5;
+ v[i].v = v[i].ny * 0.5 + 0.5;
+ }
+ if(st->opt & G3D_TEXTURE_MAT) {
+ float *mat = st->mat[G3D_TEXTURE][st->mtop[G3D_TEXTURE]];
+ float x = mat[0] * v[i].u + mat[4] * v[i].v + mat[12];
+ float y = mat[1] * v[i].u + mat[5] * v[i].v + mat[13];
+ float w = mat[3] * v[i].u + mat[7] * v[i].v + mat[15];
+ v[i].u = x / w;
+ v[i].v = y / w;
+ }
+ xform4_vec3(st->mat[G3D_PROJECTION][ptop], &v[i].x);
+ }
+
+ /* clipping */
+ if(st->opt & G3D_CLIP_FRUSTUM) {
+ for(i=0; i<6; i++) {
+ memcpy(tmpv, v, vnum * sizeof *v);
+
+ if(clip_frustum(v, &vnum, tmpv, vnum, i) < 0) {
+ /* polygon completely outside of view volume. discard */
+ vnum = 0;
+ break;
+ }
+ }
+
+ if(!vnum) continue;
+ }
+
+ for(i=0; i<vnum; i++) {
+ if(v[i].w != 0.0f) {
+ v[i].x /= v[i].w;
+ v[i].y /= v[i].w;
+ /*v[i].z /= v[i].w;*/
+ }
+
+ /* viewport transformation */
+ v[i].x = (v[i].x * 0.5f + 0.5f) * (float)st->vport[2] + st->vport[0];
+ v[i].y = (0.5f - v[i].y * 0.5f) * (float)st->vport[3] + st->vport[1];
+
+ /* convert pos to 24.8 fixed point */
+ pv[i].x = cround64(v[i].x * 256.0f);
+ pv[i].y = cround64(v[i].y * 256.0f);
+ /* convert tex coords to 16.16 fixed point */
+ pv[i].u = cround64(v[i].u * 65536.0f);
+ pv[i].v = cround64(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;
+ pv[i].a = v[i].a;
+ }
+
+ /* 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 >> 4) * (by >> 4) - (ay >> 4) * (bx >> 4);
+ int sign = (cross_z >> 31) & 1;
+
+ if(!(sign ^ st->frontface)) {
+ continue; /* back-facing */
+ }
+ }
+
+ switch(vnum) {
+ case 1:
+ if(st->opt & G3D_BLEND) {
+ int r, g, b;
+ int inv_alpha = 255 - pv[0].a;
+ uint32_t *dest = st->pixels + (pv[0].y >> 8) * st->width + (pv[0].x >> 8);
+ r = ((int)pv[0].r * pv[0].a + UNPACK_R32(*dest) * inv_alpha) >> 8;
+ g = ((int)pv[0].g * pv[0].a + UNPACK_G32(*dest) * inv_alpha) >> 8;
+ b = ((int)pv[0].b * pv[0].a + UNPACK_B32(*dest) * inv_alpha) >> 8;
+ *dest++ = PACK_RGB16(r, g, b);
+ } else {
+ uint32_t *dest = st->pixels + (pv[0].y >> 8) * st->width + (pv[0].x >> 8);
+ *dest = PACK_RGB32(pv[0].r, pv[0].g, pv[0].b);
+ }
+ break;
+
+ case 2:
+ {
+ uint32_t col = PACK_RGB32(pv[0].r, pv[0].g, pv[0].b);
+ draw_line(pv[0].x >> 8, pv[0].y >> 8, pv[1].x >> 8, pv[1].y >> 8, col);
+ }
+ break;
+
+ default:
+ fill_mode = st->polymode;
+ if(st->opt & G3D_TEXTURE_2D) {
+ fill_mode |= POLYFILL_TEX_BIT;
+ }
+ if(st->opt & G3D_BLEND) {
+ fill_mode |= POLYFILL_BLEND_BIT;
+ }
+ polyfill(fill_mode, pv, vnum);
+ }
+ }
+}
+
+void g3d_begin(int prim)
+{
+ st->imm_prim = prim;
+ st->imm_pcount = prim;
+ st->imm_numv = 0;
+}
+
+void g3d_end(void)
+{
+ imm_flush();
+}
+
+static void imm_flush(void)
+{
+ int numv = st->imm_numv;
+ st->imm_numv = 0;
+ g3d_draw_indexed(st->imm_prim, st->imm_vbuf, numv, 0, 0);
+}
+
+void g3d_vertex(float x, float y, float z)
+{
+ struct g3d_vertex *vptr = st->imm_vbuf + st->imm_numv++;
+ *vptr = st->imm_curv;
+ vptr->x = x;
+ vptr->y = y;
+ vptr->z = z;
+ vptr->w = 1.0f;
+
+ if(!--st->imm_pcount) {
+ if(st->imm_numv >= IMM_VBUF_SIZE - st->imm_prim) {
+ imm_flush();
+ }
+ st->imm_pcount = st->imm_prim;
+ }
+}
+
+void g3d_normal(float x, float y, float z)
+{
+ st->imm_curv.nx = x;
+ st->imm_curv.ny = y;
+ st->imm_curv.nz = z;
+}
+
+void g3d_color3b(unsigned char r, unsigned char g, unsigned char b)
+{
+ st->imm_curv.r = r;
+ st->imm_curv.g = g;
+ st->imm_curv.b = b;
+ st->imm_curv.a = 255;
+}
+
+void g3d_color4b(unsigned char r, unsigned char g, unsigned char b, unsigned char a)
+{
+ st->imm_curv.r = r;
+ st->imm_curv.g = g;
+ st->imm_curv.b = b;
+ st->imm_curv.a = a;
+}
+
+void g3d_color3f(float r, float g, float b)
+{
+ int ir = r * 255.0f;
+ int ig = g * 255.0f;
+ int ib = b * 255.0f;
+ st->imm_curv.r = ir > 255 ? 255 : ir;
+ st->imm_curv.g = ig > 255 ? 255 : ig;
+ st->imm_curv.b = ib > 255 ? 255 : ib;
+ st->imm_curv.a = 255;
+}
+
+void g3d_color4f(float r, float g, float b, float a)
+{
+ int ir = r * 255.0f;
+ int ig = g * 255.0f;
+ int ib = b * 255.0f;
+ int ia = a * 255.0f;
+ st->imm_curv.r = ir > 255 ? 255 : ir;
+ st->imm_curv.g = ig > 255 ? 255 : ig;
+ st->imm_curv.b = ib > 255 ? 255 : ib;
+ st->imm_curv.a = ia > 255 ? 255 : ia;
+}
+
+void g3d_texcoord(float u, float v)
+{
+ st->imm_curv.u = u;
+ st->imm_curv.v = v;
+}
+
+static void xform4_vec3(const float *mat, float *vec)
+{
+ float x = mat[0] * vec[0] + mat[4] * vec[1] + mat[8] * vec[2] + mat[12];
+ float y = mat[1] * vec[0] + mat[5] * vec[1] + mat[9] * vec[2] + mat[13];
+ float z = mat[2] * vec[0] + mat[6] * vec[1] + mat[10] * vec[2] + mat[14];
+ float w = mat[3] * vec[0] + mat[7] * vec[1] + mat[11] * vec[2] + mat[15];
+
+ vec[0] = x;
+ vec[1] = y;
+ vec[2] = z;
+ vec[3] = w;
+}
+
+static void xform3_vec3(const float *mat, float *vec)
+{
+ float x = mat[0] * vec[0] + mat[4] * vec[1] + mat[8] * vec[2];
+ float y = mat[1] * vec[0] + mat[5] * vec[1] + mat[9] * vec[2];
+ float z = mat[2] * vec[0] + mat[6] * vec[1] + mat[10] * vec[2];
+
+ vec[0] = x;
+ vec[1] = y;
+ vec[2] = z;
+}
+
+#define NORMALIZE(v) \
+ do { \
+ float len = sqrt(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]); \
+ if(len != 0.0) { \
+ float s = 1.0 / len; \
+ v[0] *= s; \
+ v[1] *= s; \
+ v[2] *= s; \
+ } \
+ } while(0)
+
+static void shade(struct g3d_vertex *v)
+{
+ int i, r, g, b;
+ float color[3];
+
+ color[0] = st->ambient[0] * st->mtl.kd[0];
+ color[1] = st->ambient[1] * st->mtl.kd[1];
+ color[2] = st->ambient[2] * st->mtl.kd[2];
+
+ for(i=0; i<MAX_LIGHTS; i++) {
+ float ldir[3];
+ float ndotl;
+
+ if(!(st->opt & (G3D_LIGHT0 << i))) {
+ continue;
+ }
+
+ ldir[0] = st->lt[i].x - v->x;
+ ldir[1] = st->lt[i].y - v->y;
+ ldir[2] = st->lt[i].z - v->z;
+ NORMALIZE(ldir);
+
+ if((ndotl = v->nx * ldir[0] + v->ny * ldir[1] + v->nz * ldir[2]) < 0.0f) {
+ ndotl = 0.0f;
+ }
+
+ color[0] += st->mtl.kd[0] * st->lt[i].r * ndotl;
+ color[1] += st->mtl.kd[1] * st->lt[i].g * ndotl;
+ color[2] += st->mtl.kd[2] * st->lt[i].b * ndotl;
+ }
+
+ r = cround64(color[0] * 255.0);
+ g = cround64(color[1] * 255.0);
+ b = cround64(color[2] * 255.0);
+
+ v->r = r > 255 ? 255 : r;
+ v->g = g > 255 ? 255 : g;
+ v->b = b > 255 ? 255 : b;
+}
projects / bootcensus / commitdiff