solstice-solver

commit b8ff59859a7f002d549f165c79e85ff3ebca84d0
parent 7bef8a6c37256eb232e4458bb27c74fabf297bfa
Author: Vincent Forest <vincent.forest@meso-star.com>
Date:   Wed, 31 May 2017 12:05:58 +0200

Fix the path tracer with a spectral atmospheric absorption

Diffstat:
M
src/ssol_draw_pt.c
 | 
16
+++++++++++-----

1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/src/ssol_draw_pt.c b/src/ssol_draw_pt.c
@@ -14,6 +14,7 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>. */
 
 #include "ssol_c.h"
+#include "ssol_atmosphere_c.h"
 #include "ssol_camera.h"
 #include "ssol_device_c.h"
 #include "ssol_draw.h"
@@ -171,21 +172,26 @@ Li(struct ssol_scene* scn,
 
   wl = ranst_sun_wl_get(ctx->ran_wl, ctx->rng);
 
+  if(scn->atmosphere) {
+    ssol_data_copy(&medium.absorption, &scn->atmosphere->absorption);
+  }
+
   for(;;) {
     double absorption;
     S3D(scene_view_trace_ray
       (view, ray_org, ray_dir, ray_range, &ray_data, &hit));
 
-    absorption = ssol_data_get_value(&medium.absorption, wl);
-    if(absorption > 0) {
-      throughput *= exp(-absorption * hit.distance);
-    }
-
     if(S3D_HIT_NONE(&hit)) { /* Background lighting */
       if(f3_dot(ray_dir, ctx->up) > 0)  L += throughput * 1.e-1;
       break;
     }
 
+    absorption = ssol_data_get_value(&medium.absorption, wl);
+    if(absorption > 0) {
+      throughput *= exp(-absorption * hit.distance);
+      if(throughput <= 0) break;
+    }
+
     /* Retrieve the hit shaded shape */
     inst = *htable_instance_find(&scn->instances_rt, &hit.prim.inst_id);
     isshape = *htable_shaded_shape_find