Force billboard to render in transparent phase, won't work otherwise

src/graphics/stkbillboard.cpp

@@ -2,6 +2,7 @@
 #include "graphics/glwrap.hpp"
 #include "graphics/shaders.hpp"
 #include "graphics/irr_driver.hpp"
+#include <ISceneManager.h>
 
 using namespace irr;
 
@@ -28,6 +29,17 @@ STKBillboard::STKBillboard(irr::scene::ISceneNode* parent, irr::scene::ISceneMan
         createbillboardvao();
 }
 
+void STKBillboard::OnRegisterSceneNode()
+{
+    if (IsVisible)
+    {
+        SceneManager->registerNodeForRendering(this, scene::ESNRP_TRANSPARENT);
+    }
+
+    ISceneNode::OnRegisterSceneNode();
+}
+
+
 void STKBillboard::render()
 {
     if (irr_driver->getPhase() != TRANSPARENT_PASS)

src/graphics/stkbillboard.hpp

@@ -4,6 +4,7 @@
 #include "../lib/irrlicht/source/Irrlicht/CBillboardSceneNode.h"
 #include <IBillboardSceneNode.h>
 #include <irrTypes.h>
+#include "utils/cpp2011.h"
 
 class STKBillboard : public irr::scene::CBillboardSceneNode
 {
@@ -13,7 +14,9 @@ public:
         irr::video::SColor colorTop = irr::video::SColor(0xFFFFFFFF),
         irr::video::SColor colorBottom = irr::video::SColor(0xFFFFFFFF));
 
-    virtual void render();
+    virtual void OnRegisterSceneNode() OVERRIDE;
+
+    virtual void render() OVERRIDE;
 };
 
 #endif