--- ray/src/rt/pmapooc.h	2016/05/18 08:22:45	1.1
+++ ray/src/rt/pmapooc.h	2020/04/08 15:14:21	1.2
@@ -7,7 +7,7 @@
    supported by the Swiss National Science Foundation (SNSF, #147053)
    ==================================================================
    
-   $Id: pmapooc.h,v 1.1 2016/05/18 08:22:45 rschregle Exp $
+   $Id: pmapooc.h,v 1.2 2020/04/08 15:14:21 rschregle Exp $
 */
 
 
@@ -59,24 +59,26 @@
    void OOC_InitFindPhotons (struct PhotonMap *pmap);
    /* Initialise NN search queue prior to calling kdT_FindPhotons() */
    
-   void OOC_FindPhotons (struct PhotonMap* pmap, const FVECT pos, 
-                         const FVECT norm);
+   int OOC_FindPhotons (struct PhotonMap* pmap, const FVECT pos, 
+                        const FVECT norm);
    /* Locate pmap -> squeue.len nearest photons to pos with similar normal
     * (NULL for volume photons) and return in search queue pmap -> squeue,
-    * starting with the further photon at pmap -> squeue.node */
+    * starting with the further photon at pmap -> squeue.node. Return -1 
+    * if none found, else 0. */
 
-   void OOC_Find1Photon (struct PhotonMap* pmap, const FVECT pos, 
-                         const FVECT norm, Photon *photon);
-   /* Locate single nearest photon to pos with similar normal */   
+   int OOC_Find1Photon (struct PhotonMap* pmap, const FVECT pos, 
+                        const FVECT norm, Photon *photon);
+   /* Locate single nearest photon to pos with similar normal. Return -1 
+    * if none found, else 0. */   
     
    int OOC_GetPhoton (struct PhotonMap *pmap, PhotonIdx idx, 
                       Photon *photon);
-   /* Retrieve photon referenced by idx from leaf file and return 0 on
-    * success, else -1. */                      
+   /* Retrieve photon referenced by idx from leaf file and return -1 on
+    * error, else 0. */                      
 
    Photon *OOC_GetNearestPhoton (const PhotonSearchQueue *squeue, 
                                  PhotonIdx idx);
-   /* Retrieve photon from NN search queue after OOC_FindPhotons() */                                
+   /* Retrieve photon from NN search queue after OOC_FindPhotons() */
 
    PhotonIdx OOC_FirstPhoton (const struct PhotonMap* pmap);
    /* Return index to first photon in octree */