nullvideo: initial release of null video backend

Source/Core/VideoBackends/Null/ShaderCache.cpp

@@ -0,0 +1,76 @@
+// Copyright 2015 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include "VideoBackends/Null/ShaderCache.h"
+
+#include "VideoCommon/Debugger.h"
+#include "VideoCommon/Statistics.h"
+
+namespace Null
+{
+template <typename Uid>
+ShaderCache<Uid>::ShaderCache()
+{
+  Clear();
+
+  SETSTAT(stats.numPixelShadersCreated, 0);
+  SETSTAT(stats.numPixelShadersAlive, 0);
+}
+
+template <typename Uid>
+ShaderCache<Uid>::~ShaderCache()
+{
+  Clear();
+}
+
+template <typename Uid>
+void ShaderCache<Uid>::Clear()
+{
+  m_shaders.clear();
+  m_last_entry = nullptr;
+}
+
+template <typename Uid>
+bool ShaderCache<Uid>::SetShader(DSTALPHA_MODE dst_alpha_mode, u32 primitive_type)
+{
+  Uid uid = GetUid(dst_alpha_mode, primitive_type, API_OPENGL);
+
+  // Check if the shader is already set
+  if (m_last_entry)
+  {
+    if (uid == m_last_uid)
+    {
+      return true;
+    }
+  }
+
+  m_last_uid = uid;
+
+  // Check if the shader is already in the cache
+  auto iter = m_shaders.find(uid);
+  if (iter != m_shaders.end())
+  {
+    const std::string& entry = iter->second;
+    m_last_entry = &entry;
+
+    GFX_DEBUGGER_PAUSE_AT(NEXT_PIXEL_SHADER_CHANGE, true);
+    return true;
+  }
+
+  // Need to compile a new shader
+  ShaderCode code = GenerateCode(dst_alpha_mode, primitive_type, API_OPENGL);
+  m_shaders.emplace(uid, code.GetBuffer());
+
+  GFX_DEBUGGER_PAUSE_AT(NEXT_PIXEL_SHADER_CHANGE, true);
+  return true;
+}
+
+template class ShaderCache<VertexShaderUid>;
+template class ShaderCache<GeometryShaderUid>;
+template class ShaderCache<PixelShaderUid>;
+
+std::unique_ptr<VertexShaderCache> VertexShaderCache::s_instance;
+std::unique_ptr<GeometryShaderCache> GeometryShaderCache::s_instance;
+std::unique_ptr<PixelShaderCache> PixelShaderCache::s_instance;
+}