added texture mapping

[dosdemo] / src / 3dgfx.c

diff --git a/src/3dgfx.c b/src/3dgfx.c
index 41b3959..47b3830 100644 (file)
--- a/src/3dgfx.c
+++ b/src/3dgfx.c
@@ -6,11 +6,24 @@
 #include "3dgfx.h"
 #include "polyfill.h"
 #include "inttypes.h"
+#include "util.h"
 
 #define STACK_SIZE     8
 typedef float g3d_matrix[16];
 
 #define MAX_VBUF_SIZE  256
+#define MAX_LIGHTS             4
+
+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;
@@ -23,6 +36,10 @@ struct g3d_state {
 
        g3d_matrix norm_mat;
 
+       float ambient[3];
+       struct light lt[MAX_LIGHTS];
+       struct material mtl;
+
        int width, height;
        void *pixels;
 };
@@ -53,6 +70,13 @@ int g3d_init(void)
                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;
 }
 
@@ -67,9 +91,9 @@ void g3d_framebuffer(int width, int height, void *pixels)
        st->height = height;
        st->pixels = pixels;
 
-       pimg_fb.pixels = pixels;
-       pimg_fb.width = width;
-       pimg_fb.height = height;
+       pfill_fb.pixels = pixels;
+       pfill_fb.width = width;
+       pfill_fb.height = height;
 }
 
 void g3d_enable(unsigned int opt)
@@ -272,6 +296,77 @@ const float *g3d_get_matrix(int which, float *m)
        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);
@@ -321,11 +416,11 @@ void g3d_draw_indexed(int prim, const struct g3d_vertex *varr, int varr_size,
                        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);
+                       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 = (int32_t)(v[i].u * 65536.0f);
-                       pv[i].v = (int32_t)(v[i].v * 65536.0f);
+                       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;
@@ -374,7 +469,53 @@ static void xform3_vec3(const float *mat, float *vec)
        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)
 {
-       v->r = v->g = v->b = 255;
+       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;
 }