ref: soft: rework @SNMetamorph's fix for avoiding crash when no world is set (like Customize menu with enabled 3D view)

ref/soft/r_light.c

@@ -156,7 +156,11 @@ void R_PushDlights( void )
 	tr.dlightframecount = tr.framecount;
 
 	RI.currententity = CL_GetEntityByIndex( 0 );
-	if( RI.currententity )
+
+	// no world -- no dlights
+	if( !RI.currententity )
+		return;
+
 	RI.currentmodel = RI.currententity->model;
 
 	for( i = 0; i < MAX_DLIGHTS; i++, l++ )
@@ -169,7 +173,6 @@ void R_PushDlights( void )
 		//if( GL_FrustumCullSphere( &RI.frustum, l->origin, l->radius, 15 ))
 			//continue;
 
-		if( RI.currententity )
 		R_MarkLights( l, 1<<i, RI.currentmodel->nodes );
 	}
 }