Make number of raytracing worker threads configurable.

3 files changed, 18 insertions, 12 deletions

diff --git a/libdimension/dimension/scene.h b/libdimension/dimension/scene.h
index 2064792..ffc8517 100644
--- a/libdimension/dimension/scene.h
+++ b/libdimension/dimension/scene.h
@@ -57,6 +57,9 @@ typedef struct {
 
   /* Recursion limit */
   unsigned int limit;
+
+  /* Number of paralell threads */
+  unsigned int nthreads;
 } dmnsn_scene;
 
 /* Create a scene */
diff --git a/libdimension/raytrace.c b/libdimension/raytrace.c
index 0e197a9..31ce24e 100644
--- a/libdimension/raytrace.c
+++ b/libdimension/raytrace.c
@@ -109,18 +109,20 @@ static void *dmnsn_raytrace_scene_multithread_thread(void *ptr);
 static int
 dmnsn_raytrace_scene_multithread(dmnsn_raytrace_payload *payload)
 {
-  int i, j, nthreads;
+  int i, j, nthreads = payload->scene->nthreads;
   void *ptr;
   int retval = 0;
   dmnsn_raytrace_payload *payloads;
   pthread_t *threads;
 
-  /* Find the number of processors/cores running (TODO: do this portably) */
-  nthreads = sysconf(_SC_NPROCESSORS_ONLN);
-  if (nthreads < 1) {
-    nthreads = 1;
+  if (!nthreads) {
+    /* Find the number of processors/cores running (TODO: do this portably) */
+    nthreads = sysconf(_SC_NPROCESSORS_ONLN);
+    if (nthreads < 1) {
+      nthreads = 1;
+    }
+    /* End non-portable section */
   }
-  /* End non-portable section */
 
   payloads = malloc(nthreads*sizeof(dmnsn_raytrace_payload));
   if (!payloads) {
diff --git a/libdimension/scene.c b/libdimension/scene.c
index 78e1ffb..aec9b12 100644
--- a/libdimension/scene.c
+++ b/libdimension/scene.c
@@ -33,12 +33,13 @@ dmnsn_new_scene()
       return NULL;
     }
 
-    scene->camera  = NULL;
-    scene->canvas  = NULL;
-    scene->objects = dmnsn_new_array(sizeof(dmnsn_object *));
-    scene->lights  = dmnsn_new_array(sizeof(dmnsn_light *));
-    scene->quality = DMNSN_RENDER_FULL;
-    scene->limit   = 10;
+    scene->camera   = NULL;
+    scene->canvas   = NULL;
+    scene->objects  = dmnsn_new_array(sizeof(dmnsn_object *));
+    scene->lights   = dmnsn_new_array(sizeof(dmnsn_light *));
+    scene->quality  = DMNSN_RENDER_FULL;
+    scene->limit    = 10;
+    scene->nthreads = 0;
   }
   return scene;
 }