Added safety offset on lighting

This avoids shadow algorithm to hit the surface it is currently checking

src/render/software/GodRaysSampler.cpp

@@ -110,6 +110,7 @@ Color GodRaysSampler::getRawLight(const Vector3 &location, bool filtered) const
     if (lighting)
     {
         LightStatus status(lighting, location, *camera_location, filtered);
+        status.setSafetyOffset(0.0);  // Not a hard surface, safety offset not needed
         lighting->fillStatus(status, location);
         return status.getSum();
     }

src/render/software/LightStatus.cpp

@@ -7,6 +7,7 @@
 
 LightStatus::LightStatus(LightingManager *manager, const Vector3 &location, const Vector3 &eye, bool filtered)
 {
+    this->safety_offset = -0.0000001;
     this->max_power = 0.0;
     this->manager = manager;
     this->location = location;
@@ -25,7 +26,7 @@ void LightStatus::pushComponent(LightComponent component)
             return;
         }
 
-        if (manager->alterLight(component, location))
+        if (manager->alterLight(component, location.add(component.direction.scale(safety_offset))))
         {
             if (power > max_power)
             {
@@ -64,3 +65,8 @@ Color LightStatus::getSum() const
 
     return final;
 }
+
+void LightStatus::setSafetyOffset(double safety_offset)
+{
+    this->safety_offset = -safety_offset;
+}

src/render/software/LightStatus.h

@@ -29,7 +29,17 @@ public:
      */
     Color getSum() const;
 
+    /**
+     * Set the safety offset for this status.
+     *
+     * The offset is used to not hit the surface we are currently working on immediately.
+     * It adds a small vector toward the light at the start of shadow casting.
+     * This number should remain very small to not produce precision errors.
+     */
+    void setSafetyOffset(double safety_offset);
+
 private:
+    double safety_offset;
     double max_power;
     LightingManager* manager;
     Vector3 location;

src/render/software/LightingManager.cpp

@@ -10,6 +10,7 @@
 LightingManager::LightingManager()
 {
     specularity = true;
+    filtering = true;
 }
 
 int LightingManager::getStaticLightsCount() const
@@ -81,7 +82,7 @@ void LightingManager::unregisterFilter(LightFilter *filter)
 
 bool LightingManager::alterLight(LightComponent &component, const Vector3 &location)
 {
-    if (component.altered)
+    if (filtering and component.altered)
     {
         for (auto filter:filters)
         {
@@ -105,6 +106,11 @@ void LightingManager::setSpecularity(bool enabled)
     specularity = enabled;
 }
 
+void LightingManager::setFiltering(bool enabled)
+{
+    filtering = enabled;
+}
+
 Color LightingManager::applyFinalComponent(const LightComponent &component, const Vector3 &eye, const Vector3 &location, const Vector3 &normal, const SurfaceMaterial &material)
 {
     Color result, light_color;

src/render/software/LightingManager.h

@@ -77,6 +77,11 @@ public:
      */
     void setSpecularity(bool enabled);
 
+    /**
+     * Enable or disable the filtering (shadows).
+     */
+    void setFiltering(bool enabled);
+
     /**
      * Apply a final component on a surface material.
      */
@@ -93,11 +98,11 @@ public:
     Color apply(const Vector3 &eye, const Vector3 &location, const Vector3 &normal, const SurfaceMaterial &material);
 
 private:
-    int specularity;
+    bool specularity;
+    bool filtering;
     std::vector<LightComponent> static_lights;
     std::vector<LightFilter *> filters;
     std::vector<LightSource *> sources;
-
 };
 
 }