From 90fd614536913a34592ba270d8505ca48bd417cb Mon Sep 17 00:00:00 2001
From: kgv <kgv@opencascade.com>
Date: Wed, 17 Oct 2018 14:01:30 +0300
Subject: [PATCH] 0030248: Volume Rendering - importing volume with default
 parameters leads to crashes within OpenGl_Texture::Init3D()

---
 src/OpenGl/OpenGl_Texture.cxx | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/OpenGl/OpenGl_Texture.cxx b/src/OpenGl/OpenGl_Texture.cxx
index c4de253714..6256e1f150 100644
--- a/src/OpenGl/OpenGl_Texture.cxx
+++ b/src/OpenGl/OpenGl_Texture.cxx
@@ -30,7 +30,7 @@ struct OpenGl_UnpackAlignmentSentry
 {
 
   //! Reset unpack alignment settings to safe values
-  void Reset()
+  static void Reset()
   {
     glPixelStorei (GL_UNPACK_ALIGNMENT,  1);
   #if !defined(GL_ES_VERSION_2_0)
@@ -38,6 +38,8 @@ struct OpenGl_UnpackAlignmentSentry
   #endif
   }
 
+  OpenGl_UnpackAlignmentSentry() {}
+
   ~OpenGl_UnpackAlignmentSentry()
   {
     Reset();
@@ -840,6 +842,9 @@ bool OpenGl_Texture::InitRectangle (const Handle(OpenGl_Context)& theCtx,
   myTextFormat  = theFormat.Format();
   mySizedFormat = theFormat.Internal();
 
+  // setup the alignment
+  OpenGl_UnpackAlignmentSentry::Reset();
+
   glTexImage2D (GL_PROXY_TEXTURE_RECTANGLE, 0, mySizedFormat,
                 aSizeX, aSizeY, 0,
                 myTextFormat, GL_FLOAT, NULL);
@@ -938,6 +943,9 @@ bool OpenGl_Texture::Init3D (const Handle(OpenGl_Context)& theCtx,
 
   mySizedFormat = theTextFormat;
 
+  // setup the alignment
+  OpenGl_UnpackAlignmentSentry::Reset();
+
 #if !defined (GL_ES_VERSION_2_0)
   theCtx->core15fwd->glTexImage3D (GL_PROXY_TEXTURE_3D, 0, mySizedFormat,
                                    aSizeX, aSizeY, aSizeZ, 0,