From b359a731067c9c765a5d8fd8ca69d2090b439401 Mon Sep 17 00:00:00 2001
From: kgv <kgv@opencascade.com>
Date: Wed, 14 Feb 2018 20:18:39 +0300
Subject: [PATCH] 0029508: Visualization, TKOpenGl - visual artifacts on Adreno
 305/308

OpenGl_ShaderManager now:
- prefers GLSL ES 100 over GLSL ES 300 on devices reporting OpenGL ES 3.0;
- prefers GLSL ES 300 on devices reporting OpenGL ES 3.1+.
to workaround known buggy implementations of OpenGL ES 3.0 drivers.
---
 src/OpenGl/OpenGl_ShaderManager.cxx | 39 ++++++++++++++++++++++++-----
 1 file changed, 33 insertions(+), 6 deletions(-)

diff --git a/src/OpenGl/OpenGl_ShaderManager.cxx b/src/OpenGl/OpenGl_ShaderManager.cxx
index 27d96f9f38..f57e4a9b66 100644
--- a/src/OpenGl/OpenGl_ShaderManager.cxx
+++ b/src/OpenGl/OpenGl_ShaderManager.cxx
@@ -1185,8 +1185,10 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramFont()
     aProgramSrc->SetHeader ("#version 150");
   }
 #else
-  if (myContext->IsGlGreaterEqual (3, 0))
+  if (myContext->IsGlGreaterEqual (3, 1))
   {
+    // prefer "100 es" on OpenGL ES 3.0 devices
+    // and    "300 es" on newer devices (3.1+)
     aProgramSrc->SetHeader ("#version 300 es");
   }
 #endif
@@ -1520,6 +1522,12 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramFlat (Handle(OpenGl_Shad
   {
     aProgramSrc->SetNbFragmentOutputs (2);
     aProgramSrc->SetWeightOitOutput (true);
+  #if defined(GL_ES_VERSION_2_0)
+    if (myContext->IsGlGreaterEqual (3, 0))
+    {
+      aProgramSrc->SetHeader ("#version 300 es");
+    }
+  #endif
   }
 
   TCollection_AsciiString aSrcVertEndMain;
@@ -1529,6 +1537,7 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramFlat (Handle(OpenGl_Shad
   #if defined(GL_ES_VERSION_2_0)
     if (myContext->IsGlGreaterEqual (3, 0))
     {
+      aProgramSrc->SetHeader ("#version 300 es");
       hasGlslBitOps = true;
     }
   #else
@@ -1599,8 +1608,10 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramFlat (Handle(OpenGl_Shad
     aProgramSrc->SetHeader ("#version 150");
   }
 #else
-  if (myContext->IsGlGreaterEqual (3, 0))
+  if (myContext->IsGlGreaterEqual (3, 1))
   {
+    // prefer "100 es" on OpenGL ES 3.0 devices
+    // and    "300 es" on newer devices (3.1+)
     aProgramSrc->SetHeader ("#version 300 es");
   }
 #endif
@@ -1829,6 +1840,12 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramGouraud (Handle(OpenGl_S
   {
     aProgramSrc->SetNbFragmentOutputs (2);
     aProgramSrc->SetWeightOitOutput (true);
+  #if defined(GL_ES_VERSION_2_0)
+    if (myContext->IsGlGreaterEqual (3, 0))
+    {
+      aProgramSrc->SetHeader ("#version 300 es");
+    }
+  #endif
   }
 
   Standard_Integer aNbLights = 0;
@@ -1873,8 +1890,10 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramGouraud (Handle(OpenGl_S
     aProgramSrc->SetHeader ("#version 150");
   }
 #else
-  if (myContext->IsGlGreaterEqual (3, 0))
+  if (myContext->IsGlGreaterEqual (3, 1))
   {
+    // prefer "100 es" on OpenGL ES 3.0 devices
+    // and    "300 es" on newer devices (3.1+)
     aProgramSrc->SetHeader ("#version 300 es");
   }
 #endif
@@ -2033,13 +2052,19 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramPhong (Handle(OpenGl_Sha
     aProgramSrc->SetHeader ("#version 150");
   }
 #else
-  if (myContext->IsGlGreaterEqual (3, 0))
+  if (myContext->IsGlGreaterEqual (3, 1))
   {
+    // prefer "100 es" on OpenGL ES 3.0 devices
+    // and    "300 es" on newer devices (3.1+)
     aProgramSrc->SetHeader ("#version 300 es");
   }
   else if (isFlatNormal)
   {
-    if (myContext->oesStdDerivatives)
+    if (myContext->IsGlGreaterEqual (3, 0))
+    {
+      aProgramSrc->SetHeader ("#version 300 es");
+    }
+    else if (myContext->oesStdDerivatives)
     {
       aProgramSrc->SetHeader ("#extension GL_OES_standard_derivatives : enable");
     }
@@ -2269,8 +2294,10 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramStereo (Handle(OpenGl_Sh
     aProgramSrc->SetHeader ("#version 150");
   }
 #else
-  if (myContext->IsGlGreaterEqual (3, 0))
+  if (myContext->IsGlGreaterEqual (3, 1))
   {
+    // prefer "100 es" on OpenGL ES 3.0 devices
+    // and    "300 es" on newer devices (3.1+)
     aProgramSrc->SetHeader ("#version 300 es");
   }
 #endif
-- 
2.39.5