diff --git a/3d-viewer/3d_rendering/3d_render_raytracing/accelerators/container_2d.h b/3d-viewer/3d_rendering/3d_render_raytracing/accelerators/container_2d.h
index 2214c9b35a..091b6c991b 100644
--- a/3d-viewer/3d_rendering/3d_render_raytracing/accelerators/container_2d.h
+++ b/3d-viewer/3d_rendering/3d_render_raytracing/accelerators/container_2d.h
@@ -33,7 +33,7 @@
 #include <list>
 #include <mutex>
 
-class RAYSEG2D;
+struct RAYSEG2D;
 
 typedef std::list<OBJECT_2D*> LIST_OBJECT2D;
 typedef std::list<const OBJECT_2D*> CONST_LIST_OBJECT2D;
diff --git a/3d-viewer/3d_rendering/3d_render_raytracing/shapes2D/bbox_2d.h b/3d-viewer/3d_rendering/3d_render_raytracing/shapes2D/bbox_2d.h
index 451b38182a..1fd83b282b 100644
--- a/3d-viewer/3d_rendering/3d_render_raytracing/shapes2D/bbox_2d.h
+++ b/3d-viewer/3d_rendering/3d_render_raytracing/shapes2D/bbox_2d.h
@@ -32,8 +32,8 @@
 
 #include <plugins/3dapi/xv3d_types.h>   // SFVEC2F
 
-class RAY2D;
-class RAYSEG2D;
+struct RAY2D;
+struct RAYSEG2D;
 
 /**
  * Manage a bounding box defined by two SFVEC2F min max points.
diff --git a/3d-viewer/3d_rendering/3d_render_raytracing/shapes3D/bbox_3d.h b/3d-viewer/3d_rendering/3d_render_raytracing/shapes3D/bbox_3d.h
index 44cb768a38..bda28efe79 100644
--- a/3d-viewer/3d_rendering/3d_render_raytracing/shapes3D/bbox_3d.h
+++ b/3d-viewer/3d_rendering/3d_render_raytracing/shapes3D/bbox_3d.h
@@ -32,7 +32,7 @@
 
 #include <plugins/3dapi/xv3d_types.h>   // SFVEC2F
 
-class RAY;
+struct RAY;
 
 
 /**