Add the hit function to get the closest non negative hit, and add some mecanisme to test that properly and report when no valid hit occur.

source/intersect.cpp

@@ -7,9 +7,11 @@
  *
  */
 #include <stdlib.h>
-
+#include <math_helper.h>
 #include <intersect.h>
 
+#include <float.h>
+
 #define MIN_ALLOC (2)
 
 Intersect::Intersect()
@@ -27,4 +29,26 @@ void Intersect::add(Intersection i)
         this->list = (Intersection *)realloc(this->list, sizeof(Object *) * this->allocated);
     }
     this->list[this->num++] = i;
+}
+
+Intersection Intersect::hit()
+{
+    int i;
+    double minHit = DBL_MAX;
+    uint32_t curHit = -1;
+    for(i = 0; i < this->num; i++)
+    {
+        if ((this->list[i].t >= 0) && (this->list[i].t < minHit))
+        {
+            curHit = i;
+            minHit = this->list[i].t;
+        }
+    }
+
+    if (curHit == -1)
+    {
+        return Intersection(0, nullptr);
+    }
+
+    return this->list[curHit];
 }