star-sf

commit af3f5499c28c8a909442ed7c30a5edcf21bf24ef
parent 8a68cde950b885fa209de3b5a7a2e4b5ff2e42c9
Author: Vincent Forest <vincent.forest@meso-star.com>
Date:   Mon, 19 Sep 2016 14:54:03 +0200

Implement and test the ssf_bsdf_view_eval function

Diffstat:
M
src/ssf_bsdf.c
 | 
1
-
M
src/ssf_bsdf_view.c
 | 
22
+++++++++++++++++++++-
M
src/test_ssf_bsdf_view.c
 | 
2
++

3 files changed, 23 insertions(+), 2 deletions(-)
diff --git a/src/ssf_bsdf.c b/src/ssf_bsdf.c
@@ -105,7 +105,6 @@ ssf_bsdf_add(struct ssf_bsdf* bsdf, struct ssf_bxdf* bxdf, const double weight)
   return RES_OK;
 }
 
-
 res_T
 ssf_bsdf_clear(struct ssf_bsdf* bsdf)
 {
diff --git a/src/ssf_bsdf_view.c b/src/ssf_bsdf_view.c
@@ -18,6 +18,7 @@
 #include "ssf.h"
 #include "ssf_bsdf_view_c.h"
 
+#include <rsys/double3.h>
 #include <rsys/mem_allocator.h>
 
 #include <float.h>
@@ -138,6 +139,8 @@ ssf_bsdf_view_sample
   double pdf;
   double w;
   size_t i, icomponent;
+  ASSERT(view && u>=0 && u<1 && v>=0 && v<1 && wi && N && wo);
+  ASSERT(d3_is_normalized(wi) && d3_is_normalized(N));
 
   if(!view->ncomponents) return 0;
   if(view->ncomponents == 1) {
@@ -149,7 +152,7 @@ ssf_bsdf_view_sample
     if(u >= view->cumulative[icomponent]) break;
   }
 
-  /* Rescale the random number to reuse it (NOTE why?) */
+  /* Rescale the random number to reuse it */
   w = (u - view->cumulative[icomponent] )/ nextafter
     (view->cumulative[icomponent+1] - view->cumulative[icomponent], DBL_MAX);
 
@@ -170,6 +173,23 @@ ssf_bsdf_view_sample
   return reflectivity / pdf;
 }
 
+double
+ssf_bsdf_view_eval
+  (struct ssf_bsdf_view* view,
+   const double wi[3],
+   const double wo[3])
+{
+  double R = 0;
+  size_t i;
+  ASSERT(view && wi && wo);
+  ASSERT(d3_is_normalized(wi) && d3_is_normalized(wo));
+
+  FOR_EACH(i, 0, view->ncomponents) {
+    R += ssf_bxdf_eval(view->components[i], wi, wo) * view->probas[i];
+  }
+  return R;
+}
+
 /*******************************************************************************
  * Local functions
  ******************************************************************************/
diff --git a/src/test_ssf_bsdf_view.c b/src/test_ssf_bsdf_view.c
@@ -77,6 +77,7 @@ main(int argc, char** argv)
     const double u = rand_canonic();
     const double v = rand_canonic();
     const double weight = ssf_bsdf_view_sample(view, u, v, w, N, dir);
+    CHECK(ssf_bsdf_view_eval(view, w, dir), 0);
     sum += weight;
     sqr_sum += weight*weight;
   }
@@ -85,6 +86,7 @@ main(int argc, char** argv)
   SE = sqrt(V / (double)NSTEPS);
   CHECK(eq_eps((0.1234+0.6789) * 0.5, E, SE), 1);
 
+
   CHECK(ssf_bsdf_view_ref_get(NULL), RES_BAD_ARG);
   CHECK(ssf_bsdf_view_ref_get(view), RES_OK);
   CHECK(ssf_bsdf_view_ref_put(NULL), RES_BAD_ARG);