subtraction seems to work now

[csgray] / src / csgray.c

diff --git a/src/csgray.c b/src/csgray.c
index 53b0146..44c7eb9 100644 (file)
--- a/src/csgray.c
+++ b/src/csgray.c
@@ -23,7 +23,7 @@ int csg_init(void)
        oblist = 0;
        plights = 0;
 
-       csg_ambient(0.05, 0.05, 0.05);
+       csg_ambient(0, 0, 0);
        csg_view(0, 0, 5, 0, 0, 0);
        csg_fov(50);
 
@@ -198,7 +198,7 @@ csg_object *csg_plane(float x, float y, float z, float nx, float ny, float nz)
        o->plane.ny = ny;
        o->plane.nz = nz;
        o->plane.d = x * nx + y * ny + z * nz;
-       return 0;
+       return o;
 }
 
 csg_object *csg_box(float x, float y, float z, float xsz, float ysz, float zsz)
@@ -326,7 +326,7 @@ static int ray_trace(struct ray *ray, float *col)
 
 static void shade(float *col, struct ray *ray, struct hit *hit)
 {
-       float ndotl, len;
+       float ndotl, len, falloff;
        csg_object *o, *lt = plights;
        float dcol[3], scol[3] = {0};
        float ldir[3];
@@ -350,24 +350,25 @@ static void shade(float *col, struct ray *ray, struct hit *hit)
                sray.dy = ldir[1];
                sray.dz = ldir[2];
 
-               if(!find_intersection(&sray, &tmphit) || tmphit.t < 1.0f) {
+               if(!find_intersection(&sray, &tmphit) || tmphit.t > 1.0f) {
                        if((len = sqrt(ldir[0] * ldir[0] + ldir[1] * ldir[1] + ldir[2] * ldir[2])) != 0.0f) {
                                float s = 1.0f / len;
                                ldir[0] *= s;
                                ldir[1] *= s;
                                ldir[2] *= s;
                        }
+                       falloff = 1.0f / (len * len);
 
                        if((ndotl = hit->nx * ldir[0] + hit->ny * ldir[1] + hit->nz * ldir[2]) < 0.0f) {
                                ndotl = 0.0f;
                        }
 
-                       dcol[0] += o->ob.r * lt->ob.emr * ndotl;
-                       dcol[1] += o->ob.g * lt->ob.emg * ndotl;
-                       dcol[2] += o->ob.b * lt->ob.emb * ndotl;
+                       dcol[0] += o->ob.r * lt->ob.emr * ndotl * falloff;
+                       dcol[1] += o->ob.g * lt->ob.emg * ndotl * falloff;
+                       dcol[2] += o->ob.b * lt->ob.emb * ndotl * falloff;
                }
 
-               lt = lt->ob.next;
+               lt = lt->ob.plt_next;
        }
 
        col[0] = dcol[0] + scol[0];
@@ -382,16 +383,32 @@ static void background(float *col, struct ray *ray)
 
 static int find_intersection(struct ray *ray, struct hit *best)
 {
+       int idx = 0;
        csg_object *o;
-       struct hit *hit;
+       struct hinterv *hit, *it;
 
        best->t = FLT_MAX;
        best->o = 0;
 
        o = oblist;
        while(o) {
-               if((hit = ray_intersect(ray, o)) && hit->t < best->t) {
-                       *best = *hit;
+               if((hit = ray_intersect(ray, o))) {
+                       it = hit;
+                       while(it) {
+                               if(it->end[0].t > 1e-6) {
+                                       idx = 0;
+                                       break;
+                               }
+                               if(it->end[1].t > 1e-6) {
+                                       idx = 1;
+                                       break;
+                               }
+                               it = it->next;
+                       }
+
+                       if(it && it->end[idx].t < best->t) {
+                               *best = it->end[idx];
+                       }
                }
                free_hit_list(hit);
                o = o->ob.next;