Pyramid6 fixed

GUI/ba3d/model/particles.cpp

@@ -158,9 +158,8 @@ Cone::Cone(float R, float H, float alpha)
     set();
 }
 
-// TODO : BUG : wrong parametrization
 Pyramid6::Pyramid6(float R, float H, float alpha)
-    : Particle(Key(BaseShape::Column, (1.0f - H / (R * std::tan(alpha))), 6))
+    : Particle(Key(BaseShape::Column, (1.0f - H / (R * sqrt3f/2* std::tan(alpha))), 6))
 {
     isNull = (R <= 0 || H <= 0 || alpha <= 0);
     scale = Vector3D(R * 2, R * 2, H);