+++ /dev/null
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <math.h>
-#include <assert.h>
-#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;
-};
-
-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;
- }
-
- for(i=0; i<G3D_NUM_MATRICES; i++) {
- g3d_matrix_mode(i);
- g3d_load_identity();
- }
- 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;
-}
-
-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_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);
-}
-
-#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;
- 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) {
- varr_size -= vnum;
-
- for(i=0; i<vnum; i++) {
- v[i] = *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);
- }
- xform4_vec3(st->mat[G3D_PROJECTION][ptop], &v[i].x);
- }
-
- /* TODO clipping */
-
- 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->width;
- 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);
- }
-}
-
-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;
-}
-
-static void shade(struct g3d_vertex *v)
-{
- v->r = v->g = v->b = 255;
-}
projects / dosdemo / blobdiff