From 9190810c1f5360a7130e9d78d57365e157e9bc43 Mon Sep 17 00:00:00 2001
From: enricoturri1966 <enricoturri@seznam.cz>
Date: Mon, 17 Jan 2022 08:04:07 +0100
Subject: [PATCH] Fixed volume transparency when changing volume type

---
 src/slic3r/GUI/GLCanvas3D.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/slic3r/GUI/GLCanvas3D.cpp b/src/slic3r/GUI/GLCanvas3D.cpp
index 9fc170ce8e..b0026735d1 100644
--- a/src/slic3r/GUI/GLCanvas3D.cpp
+++ b/src/slic3r/GUI/GLCanvas3D.cpp
@@ -1845,6 +1845,13 @@ void GLCanvas3D::reload_scene(bool refresh_immediately, bool force_full_scene_re
 
                 volume->is_modifier = !mvs->model_volume->is_model_part();
                 volume->set_color(color_from_model_volume(*mvs->model_volume));
+                // force update of render_color alpha channel 
+                bool transparent = volume->color[3] < 1.0f;
+                if (transparent)
+                    volume->force_transparent = true;
+                volume->set_render_color();
+                if (transparent)
+                    volume->force_transparent = false;
 
                 // updates volumes transformations
                 volume->set_instance_transformation(mvs->model_volume->get_object()->instances[mvs->composite_id.instance_id]->get_transformation());