Merge pull request #1180 from rokuz/fixed-tegra2-alpha-blendingandroid-release-541

Fixed Tegra alpha blending issue

4 files changed, 33 insertions, 4 deletions

diff --git a/drape/gpu_program.cpp b/drape/gpu_program.cpp
index 4ce50a0e82..919b3ce95a 100644
--- a/drape/gpu_program.cpp
+++ b/drape/gpu_program.cpp
@@ -1,5 +1,6 @@
 #include "drape/gpu_program.hpp"
 #include "drape/glfunctions.hpp"
+#include "drape/support_manager.hpp"
 
 #include "base/assert.hpp"
 #include "base/logging.hpp"
@@ -12,10 +13,12 @@ namespace dp
 {
 
 GpuProgram::GpuProgram(ref_ptr<Shader> vertexShader, ref_ptr<Shader> fragmentShader)
+  : m_vertexShader(vertexShader)
+  , m_fragmentShader(fragmentShader)
 {
   m_programID = GLFunctions::glCreateProgram();
-  GLFunctions::glAttachShader(m_programID, vertexShader->GetID());
-  GLFunctions::glAttachShader(m_programID, fragmentShader->GetID());
+  GLFunctions::glAttachShader(m_programID, m_vertexShader->GetID());
+  GLFunctions::glAttachShader(m_programID, m_fragmentShader->GetID());
 
   string errorLog;
   if (!GLFunctions::glLinkProgram(m_programID, errorLog))
@@ -25,13 +28,25 @@ GpuProgram::GpuProgram(ref_ptr<Shader> vertexShader, ref_ptr<Shader> fragmentSha
   // on Tegra3, glGetActiveUniform will not work if you detach shaders after linking
   LoadUniformLocations();
 
-  GLFunctions::glDetachShader(m_programID, vertexShader->GetID());
-  GLFunctions::glDetachShader(m_programID, fragmentShader->GetID());
+  // On Tegra2 we cannot detach shaders at all.
+  // https://devtalk.nvidia.com/default/topic/528941/alpha-blending-not-working-on-t20-and-t30-under-ice-cream-sandwich/
+  if (!SupportManager::Instance().IsTegraDevice())
+  {
+    GLFunctions::glDetachShader(m_programID, m_vertexShader->GetID());
+    GLFunctions::glDetachShader(m_programID, m_fragmentShader->GetID());
+  }
 }
 
 GpuProgram::~GpuProgram()
 {
   Unbind();
+
+  if (SupportManager::Instance().IsTegraDevice())
+  {
+    GLFunctions::glDetachShader(m_programID, m_vertexShader->GetID());
+    GLFunctions::glDetachShader(m_programID, m_fragmentShader->GetID());
+  }
+
   GLFunctions::glDeleteProgram(m_programID);
 }
 
diff --git a/drape/gpu_program.hpp b/drape/gpu_program.hpp
index 4092dfaefd..ce118a35a6 100644
--- a/drape/gpu_program.hpp
+++ b/drape/gpu_program.hpp
@@ -32,6 +32,9 @@ private:
 private:
   uint32_t m_programID;
 
+  ref_ptr<Shader> m_vertexShader;
+  ref_ptr<Shader> m_fragmentShader;
+
   using TUniformLocations = map<string, int8_t>;
   TUniformLocations m_uniforms;
 };
diff --git a/drape/support_manager.cpp b/drape/support_manager.cpp
index d5a7376ea9..3aad71859a 100644
--- a/drape/support_manager.cpp
+++ b/drape/support_manager.cpp
@@ -29,6 +29,10 @@ void SupportManager::Init()
       }
     }
   }
+
+  m_isTegra = (renderer.find("Tegra") != string::npos);
+  if (m_isTegra)
+    LOG(LINFO, ("NVidia Tegra device detected."));
 }
 
 bool SupportManager::IsSamsungGoogleNexus() const
@@ -41,6 +45,11 @@ bool SupportManager::IsAdreno200Device() const
   return m_isAdreno200;
 }
 
+bool SupportManager::IsTegraDevice() const
+{
+  return m_isTegra;
+}
+
 SupportManager & SupportManager::Instance()
 {
   static SupportManager manager;
diff --git a/drape/support_manager.hpp b/drape/support_manager.hpp
index d2d95b2f07..ec45097d84 100644
--- a/drape/support_manager.hpp
+++ b/drape/support_manager.hpp
@@ -15,6 +15,7 @@ public:
 
   bool IsSamsungGoogleNexus() const;
   bool IsAdreno200Device() const;
+  bool IsTegraDevice() const;
 
 private:
   SupportManager() = default;
@@ -22,6 +23,7 @@ private:
 
   bool m_isSamsungGoogleNexus = false;
   bool m_isAdreno200 = false;
+  bool m_isTegra = false;
 };
 
 } // namespace dp