From b1430e72bc252867289b45de9a94041841fade06 Mon Sep 17 00:00:00 2001
From: vsr <vsr@opencascade.com>
Date: Thu, 6 May 2021 09:55:19 +0300
Subject: [PATCH] Add patch for OCCT for correct rendering transparent objects

---
 config/patches/occt.001_transparency.patch | 25 ++++++++++++++++++++++
 config/salome.xml                          |  6 +++++-
 2 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 config/patches/occt.001_transparency.patch

diff --git a/config/patches/occt.001_transparency.patch b/config/patches/occt.001_transparency.patch
new file mode 100644
index 0000000..175bd7e
--- /dev/null
+++ b/config/patches/occt.001_transparency.patch
@@ -0,0 +1,25 @@
+diff -Naur OCCT-7.5.0p1_SRC_orig/src/OpenGl/OpenGl_LayerList.cxx OCCT-7.5.0p1_SRC_modif/src/OpenGl/OpenGl_LayerList.cxx
+--- OCCT-7.5.0p1_SRC_orig/src/OpenGl/OpenGl_LayerList.cxx
++++ OCCT-7.5.0p1_SRC_modif/src/OpenGl/OpenGl_LayerList.cxx
+@@ -889,7 +889,7 @@
+   }
+   else
+   {
+-    aCtx->core11fwd->glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
++    aCtx->core15fwd->glBlendFuncSeparate (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ONE);
+   }
+ 
+   // During blended order-independent transparency pass the depth test
+diff -Naur OCCT-7.5.0p1_SRC_orig/src/OpenGl/OpenGl_View_Redraw.cxx OCCT-7.5.0p1_SRC_modif/src/OpenGl/OpenGl_View_Redraw.cxx
+--- OCCT-7.5.0p1_SRC_orig/src/OpenGl/OpenGl_View_Redraw.cxx
++++ OCCT-7.5.0p1_SRC_modif/src/OpenGl/OpenGl_View_Redraw.cxx
+@@ -933,7 +933,7 @@
+ #endif
+ 
+   const OpenGl_Vec4 aBgColor = aCtx->Vec4FromQuantityColor (myBgColor);
+-  glClearColor (aBgColor.r(), aBgColor.g(), aBgColor.b(), 0.0f);
++  glClearColor (aBgColor.r(), aBgColor.g(), aBgColor.b(), 1.0f);
+ 
+   glClear (toClear);
+ 
+
diff --git a/config/salome.xml b/config/salome.xml
index 3fee4ed..2b988a8 100644
--- a/config/salome.xml
+++ b/config/salome.xml
@@ -73,7 +73,11 @@
       <patch comment="Fix problem with shell command" name="numpy.001_shell.patch" sha1="d004dfb9053fcc7bcdc021e8c7aa3eb552a80452" />
     </patches>
   </product>
-  <product name="occt" version="7.5.0p1" />
+  <product name="occt" version="7.5.0p1">
+    <patches>
+      <patch comment="Fix problem with rendering transparent objects" name="occt.001_transparency.patch" sha1="958c573a558397560a2d5bcc0ee4e3b7258ee7fe" />
+    </patches>
+  </product>
   <product name="omniorb" version="4.2.2" />
   <product name="omniorbpy" version="4.2.2" />
   <product name="opencv" version="3.2.0">
-- 
2.39.2