diff --git a/src/pe/raytracing/Raytracer.cpp b/src/pe/raytracing/Raytracer.cpp
index a9ef0546f5aadd121e8ad79266622ab138b9a8da..33b40ab8f781317ad5973b0818e0f9146a4d592e 100644
--- a/src/pe/raytracing/Raytracer.cpp
+++ b/src/pe/raytracing/Raytracer.cpp
@@ -179,7 +179,7 @@ void Raytracer::writeTBufferToFile(const std::vector<real_t>& tBuffer, const std
  * Checks if a plane should get rendered by comparing the planes normal and the ray direction.
  * If the rays direction vectors projection on the planes normal is positive, the plane is considered invisible.
  */
-bool Raytracer::isPlaneVisible(const PlaneID plane, const Ray& ray) const {
+inline bool Raytracer::isPlaneVisible(const PlaneID plane, const Ray& ray) const {
    return plane->getNormal() * ray.getDirection() < 0;
 }
 
@@ -188,7 +188,7 @@ bool Raytracer::isPlaneVisible(const PlaneID plane, const Ray& ray) const {
  * \param y Y component of the coordinate.
  * \return Array index.
  */
-size_t Raytracer::coordinateToArrayIndex(size_t x, size_t y) const {
+inline size_t Raytracer::coordinateToArrayIndex(size_t x, size_t y) const {
    return y*pixelsHorizontal_ + x;
 }
 }
diff --git a/src/pe/raytracing/Raytracer.h b/src/pe/raytracing/Raytracer.h
index 9efa084f49b5fd4ed24a4f59ff0eee0037c3c062..49b3c35215818086cd32c9bdc7892d59a7d77ab0 100644
--- a/src/pe/raytracing/Raytracer.h
+++ b/src/pe/raytracing/Raytracer.h
@@ -124,8 +124,8 @@ public:
 private:
    void writeTBufferToFile(const std::vector<real_t>& tBuffer, size_t timestep, bool isGlobalImage = false) const;
    void writeTBufferToFile(const std::vector<real_t>& tBuffer, const std::string& fileName) const;
-   bool isPlaneVisible(const PlaneID plane, const Ray& ray) const;
-   size_t coordinateToArrayIndex(size_t x, size_t y) const;
+   inline bool isPlaneVisible(const PlaneID plane, const Ray& ray) const;
+   inline size_t coordinateToArrayIndex(size_t x, size_t y) const;
    //@}
 };