1 files changed, 615 insertions, 0 deletions

diff --git a/xbmc/utils/EGLUtils.cpp b/xbmc/utils/EGLUtils.cpp
new file mode 100644
index 0000000..01df4ba
--- /dev/null
+++ b/xbmc/utils/EGLUtils.cpp
@@ -0,0 +1,615 @@
+/*
+ *  Copyright (C) 2017-2018 Team Kodi
+ *  This file is part of Kodi - https://kodi.tv
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ *  See LICENSES/README.md for more information.
+ */
+
+#include "EGLUtils.h"
+
+#include "ServiceBroker.h"
+#include "StringUtils.h"
+#include "guilib/IDirtyRegionSolver.h"
+#include "log.h"
+#include "settings/AdvancedSettings.h"
+#include "settings/SettingsComponent.h"
+
+#include <map>
+
+#include <EGL/eglext.h>
+
+namespace
+{
+//! @todo remove when Raspberry Pi updates their EGL headers
+#ifndef EGL_NO_CONFIG_KHR
+#define EGL_NO_CONFIG_KHR static_cast<EGLConfig>(0)
+#endif
+#ifndef EGL_CONTEXT_PRIORITY_LEVEL_IMG
+#define EGL_CONTEXT_PRIORITY_LEVEL_IMG 0x3100
+#endif
+#ifndef EGL_CONTEXT_PRIORITY_HIGH_IMG
+#define EGL_CONTEXT_PRIORITY_HIGH_IMG 0x3101
+#endif
+#ifndef EGL_CONTEXT_PRIORITY_MEDIUM_IMG
+#define EGL_CONTEXT_PRIORITY_MEDIUM_IMG 0x3102
+#endif
+
+#define X(VAL) std::make_pair(VAL, #VAL)
+std::map<EGLint, const char*> eglAttributes =
+{
+  // please keep attributes in accordance to:
+  // https://www.khronos.org/registry/EGL/sdk/docs/man/html/eglGetConfigAttrib.xhtml
+  X(EGL_ALPHA_SIZE),
+  X(EGL_ALPHA_MASK_SIZE),
+  X(EGL_BIND_TO_TEXTURE_RGB),
+  X(EGL_BIND_TO_TEXTURE_RGBA),
+  X(EGL_BLUE_SIZE),
+  X(EGL_BUFFER_SIZE),
+  X(EGL_COLOR_BUFFER_TYPE),
+  X(EGL_CONFIG_CAVEAT),
+  X(EGL_CONFIG_ID),
+  X(EGL_CONFORMANT),
+  X(EGL_DEPTH_SIZE),
+  X(EGL_GREEN_SIZE),
+  X(EGL_LEVEL),
+  X(EGL_LUMINANCE_SIZE),
+  X(EGL_MAX_PBUFFER_WIDTH),
+  X(EGL_MAX_PBUFFER_HEIGHT),
+  X(EGL_MAX_PBUFFER_PIXELS),
+  X(EGL_MAX_SWAP_INTERVAL),
+  X(EGL_MIN_SWAP_INTERVAL),
+  X(EGL_NATIVE_RENDERABLE),
+  X(EGL_NATIVE_VISUAL_ID),
+  X(EGL_NATIVE_VISUAL_TYPE),
+  X(EGL_RED_SIZE),
+  X(EGL_RENDERABLE_TYPE),
+  X(EGL_SAMPLE_BUFFERS),
+  X(EGL_SAMPLES),
+  X(EGL_STENCIL_SIZE),
+  X(EGL_SURFACE_TYPE),
+  X(EGL_TRANSPARENT_TYPE),
+  X(EGL_TRANSPARENT_RED_VALUE),
+  X(EGL_TRANSPARENT_GREEN_VALUE),
+  X(EGL_TRANSPARENT_BLUE_VALUE)
+};
+
+std::map<EGLenum, const char*> eglErrors =
+{
+  // please keep errors in accordance to:
+  // https://www.khronos.org/registry/EGL/sdk/docs/man/html/eglGetError.xhtml
+  X(EGL_SUCCESS),
+  X(EGL_NOT_INITIALIZED),
+  X(EGL_BAD_ACCESS),
+  X(EGL_BAD_ALLOC),
+  X(EGL_BAD_ATTRIBUTE),
+  X(EGL_BAD_CONFIG),
+  X(EGL_BAD_CONTEXT),
+  X(EGL_BAD_CURRENT_SURFACE),
+  X(EGL_BAD_DISPLAY),
+  X(EGL_BAD_MATCH),
+  X(EGL_BAD_NATIVE_PIXMAP),
+  X(EGL_BAD_NATIVE_WINDOW),
+  X(EGL_BAD_PARAMETER),
+  X(EGL_BAD_SURFACE),
+  X(EGL_CONTEXT_LOST),
+};
+
+std::map<EGLint, const char*> eglErrorType =
+{
+//! @todo remove when Raspberry Pi updates their EGL headers
+#if !defined(TARGET_RASPBERRY_PI)
+  X(EGL_DEBUG_MSG_CRITICAL_KHR),
+  X(EGL_DEBUG_MSG_ERROR_KHR),
+  X(EGL_DEBUG_MSG_WARN_KHR),
+  X(EGL_DEBUG_MSG_INFO_KHR),
+#endif
+};
+#undef X
+
+} // namespace
+
+//! @todo remove when Raspberry Pi updates their EGL headers
+#if !defined(TARGET_RASPBERRY_PI)
+void EglErrorCallback(EGLenum error, const char* command, EGLint messageType, EGLLabelKHR threadLabel, EGLLabelKHR objectLabel, const char* message)
+{
+  std::string errorStr;
+  std::string typeStr;
+
+  auto eglError = eglErrors.find(error);
+  if (eglError != eglErrors.end())
+  {
+    errorStr = eglError->second;
+  }
+
+  auto eglType = eglErrorType.find(messageType);
+  if (eglType != eglErrorType.end())
+  {
+    typeStr = eglType->second;
+  }
+
+  CLog::Log(LOGDEBUG, "EGL Debugging:\nError: {}\nCommand: {}\nType: {}\nMessage: {}", errorStr, command, typeStr, message);
+}
+#endif
+
+std::set<std::string> CEGLUtils::GetClientExtensions()
+{
+  const char* extensions = eglQueryString(EGL_NO_DISPLAY, EGL_EXTENSIONS);
+  if (!extensions)
+  {
+    return {};
+  }
+  std::set<std::string> result;
+  StringUtils::SplitTo(std::inserter(result, result.begin()), extensions, " ");
+  return result;
+}
+
+std::set<std::string> CEGLUtils::GetExtensions(EGLDisplay eglDisplay)
+{
+  const char* extensions = eglQueryString(eglDisplay, EGL_EXTENSIONS);
+  if (!extensions)
+  {
+    throw std::runtime_error("Could not query EGL for extensions");
+  }
+  std::set<std::string> result;
+  StringUtils::SplitTo(std::inserter(result, result.begin()), extensions, " ");
+  return result;
+}
+
+bool CEGLUtils::HasExtension(EGLDisplay eglDisplay, const std::string& name)
+{
+  auto exts = GetExtensions(eglDisplay);
+  return (exts.find(name) != exts.end());
+}
+
+bool CEGLUtils::HasClientExtension(const std::string& name)
+{
+  auto exts = GetClientExtensions();
+  return (exts.find(name) != exts.end());
+}
+
+void CEGLUtils::Log(int logLevel, const std::string& what)
+{
+  EGLenum error = eglGetError();
+  std::string errorStr = StringUtils::Format("0x%04X", error);
+
+  auto eglError = eglErrors.find(error);
+  if (eglError != eglErrors.end())
+  {
+    errorStr = eglError->second;
+  }
+
+  CLog::Log(logLevel, "{} ({})", what.c_str(), errorStr);
+}
+
+CEGLContextUtils::CEGLContextUtils(EGLenum platform, std::string const& platformExtension)
+: m_platform{platform}
+{
+//! @todo remove when Raspberry Pi updates their EGL headers
+#if !defined(TARGET_RASPBERRY_PI)
+  if (CEGLUtils::HasClientExtension("EGL_KHR_debug"))
+  {
+    auto eglDebugMessageControl = CEGLUtils::GetRequiredProcAddress<PFNEGLDEBUGMESSAGECONTROLKHRPROC>("eglDebugMessageControlKHR");
+
+    EGLAttrib eglDebugAttribs[] = {EGL_DEBUG_MSG_CRITICAL_KHR, EGL_TRUE,
+                                   EGL_DEBUG_MSG_ERROR_KHR, EGL_TRUE,
+                                   EGL_DEBUG_MSG_WARN_KHR, EGL_TRUE,
+                                   EGL_DEBUG_MSG_INFO_KHR, EGL_TRUE,
+                                   EGL_NONE};
+
+    eglDebugMessageControl(EglErrorCallback, eglDebugAttribs);
+  }
+#endif
+
+  m_platformSupported = CEGLUtils::HasClientExtension("EGL_EXT_platform_base") && CEGLUtils::HasClientExtension(platformExtension);
+}
+
+bool CEGLContextUtils::IsPlatformSupported() const
+{
+  return m_platformSupported;
+}
+
+CEGLContextUtils::~CEGLContextUtils()
+{
+  Destroy();
+}
+
+bool CEGLContextUtils::CreateDisplay(EGLNativeDisplayType nativeDisplay)
+{
+  if (m_eglDisplay != EGL_NO_DISPLAY)
+  {
+    throw std::logic_error("Do not call CreateDisplay when display has already been created");
+  }
+
+  m_eglDisplay = eglGetDisplay(nativeDisplay);
+  if (m_eglDisplay == EGL_NO_DISPLAY)
+  {
+    CEGLUtils::Log(LOGERROR, "failed to get EGL display");
+    return false;
+  }
+
+  return true;
+}
+
+bool CEGLContextUtils::CreatePlatformDisplay(void* nativeDisplay, EGLNativeDisplayType nativeDisplayLegacy)
+{
+  if (m_eglDisplay != EGL_NO_DISPLAY)
+  {
+    throw std::logic_error("Do not call CreateDisplay when display has already been created");
+  }
+
+#if defined(EGL_EXT_platform_base)
+  if (IsPlatformSupported())
+  {
+    // Theoretically it is possible to use eglGetDisplay() and eglCreateWindowSurface,
+    // but then the EGL library basically has to guess which platform we want
+    // if it supports multiple which is usually the case -
+    // it's better and safer to make it explicit
+
+    auto getPlatformDisplayEXT = CEGLUtils::GetRequiredProcAddress<PFNEGLGETPLATFORMDISPLAYEXTPROC>("eglGetPlatformDisplayEXT");
+    m_eglDisplay = getPlatformDisplayEXT(m_platform, nativeDisplay, nullptr);
+
+    if (m_eglDisplay == EGL_NO_DISPLAY)
+    {
+      CEGLUtils::Log(LOGERROR, "failed to get platform display");
+      return false;
+    }
+  }
+#endif
+
+  if (m_eglDisplay == EGL_NO_DISPLAY)
+  {
+    return CreateDisplay(nativeDisplayLegacy);
+  }
+
+  return true;
+}
+
+bool CEGLContextUtils::InitializeDisplay(EGLint renderingApi)
+{
+  if (!eglInitialize(m_eglDisplay, nullptr, nullptr))
+  {
+    CEGLUtils::Log(LOGERROR, "failed to initialize EGL display");
+    Destroy();
+    return false;
+  }
+
+  const char* value;
+  value = eglQueryString(m_eglDisplay, EGL_VERSION);
+  CLog::Log(LOGINFO, "EGL_VERSION = %s", value ? value : "NULL");
+
+  value = eglQueryString(m_eglDisplay, EGL_VENDOR);
+  CLog::Log(LOGINFO, "EGL_VENDOR = %s", value ? value : "NULL");
+
+  value = eglQueryString(m_eglDisplay, EGL_EXTENSIONS);
+  CLog::Log(LOGINFO, "EGL_EXTENSIONS = %s", value ? value : "NULL");
+
+  value = eglQueryString(EGL_NO_DISPLAY, EGL_EXTENSIONS);
+  CLog::Log(LOGINFO, "EGL_CLIENT_EXTENSIONS = %s", value ? value : "NULL");
+
+  if (eglBindAPI(renderingApi) != EGL_TRUE)
+  {
+    CEGLUtils::Log(LOGERROR, "failed to bind EGL API");
+    Destroy();
+    return false;
+  }
+
+  return true;
+}
+
+bool CEGLContextUtils::ChooseConfig(EGLint renderableType, EGLint visualId, bool hdr)
+{
+  EGLint numMatched{0};
+
+  if (m_eglDisplay == EGL_NO_DISPLAY)
+  {
+    throw std::logic_error("Choosing an EGLConfig requires an EGL display");
+  }
+
+  EGLint surfaceType = EGL_WINDOW_BIT;
+  // for the non-trivial dirty region modes, we need the EGL buffer to be preserved across updates
+  int guiAlgorithmDirtyRegions = CServiceBroker::GetSettingsComponent()->GetAdvancedSettings()->m_guiAlgorithmDirtyRegions;
+  if (guiAlgorithmDirtyRegions == DIRTYREGION_SOLVER_COST_REDUCTION ||
+      guiAlgorithmDirtyRegions == DIRTYREGION_SOLVER_UNION)
+    surfaceType |= EGL_SWAP_BEHAVIOR_PRESERVED_BIT;
+
+  CEGLAttributesVec attribs;
+  attribs.Add({{EGL_RED_SIZE, 8},
+               {EGL_GREEN_SIZE, 8},
+               {EGL_BLUE_SIZE, 8},
+               {EGL_ALPHA_SIZE, 2},
+               {EGL_DEPTH_SIZE, 16},
+               {EGL_STENCIL_SIZE, 0},
+               {EGL_SAMPLE_BUFFERS, 0},
+               {EGL_SAMPLES, 0},
+               {EGL_SURFACE_TYPE, surfaceType},
+               {EGL_RENDERABLE_TYPE, renderableType}});
+
+  EGLConfig* currentConfig(hdr ? &m_eglHDRConfig : &m_eglConfig);
+
+  if (hdr)
+#if EGL_EXT_pixel_format_float
+    attribs.Add({{EGL_COLOR_COMPONENT_TYPE_EXT, EGL_COLOR_COMPONENT_TYPE_FLOAT_EXT}});
+#else
+    return false;
+#endif
+
+  const char* errorMsg = nullptr;
+
+  if (eglChooseConfig(m_eglDisplay, attribs.Get(), nullptr, 0, &numMatched) != EGL_TRUE)
+    errorMsg = "failed to query number of EGL configs";
+
+  std::vector<EGLConfig> eglConfigs(numMatched);
+  if (eglChooseConfig(m_eglDisplay, attribs.Get(), eglConfigs.data(), numMatched, &numMatched) != EGL_TRUE)
+    errorMsg = "failed to find EGL configs with appropriate attributes";
+
+  if (errorMsg)
+  {
+    if (!hdr)
+    {
+      CEGLUtils::Log(LOGERROR, errorMsg);
+      Destroy();
+    }
+    else
+      CEGLUtils::Log(LOGINFO, errorMsg);
+    return false;
+  }
+
+  EGLint id{0};
+  for (const auto &eglConfig: eglConfigs)
+  {
+    *currentConfig = eglConfig;
+
+    if (visualId == 0)
+      break;
+
+    if (eglGetConfigAttrib(m_eglDisplay, *currentConfig, EGL_NATIVE_VISUAL_ID, &id) != EGL_TRUE)
+      CEGLUtils::Log(LOGERROR, "failed to query EGL attribute EGL_NATIVE_VISUAL_ID");
+
+    if (visualId == id)
+      break;
+  }
+
+  if (visualId != 0 && visualId != id)
+  {
+    CLog::Log(LOGDEBUG, "failed to find EGL config with EGL_NATIVE_VISUAL_ID={}", visualId);
+    return false;
+  }
+
+  CLog::Log(LOGDEBUG, "EGL %sConfig Attributes:", hdr ? "HDR " : "");
+
+  for (const auto &eglAttribute : eglAttributes)
+  {
+    EGLint value{0};
+    if (eglGetConfigAttrib(m_eglDisplay, *currentConfig, eglAttribute.first, &value) != EGL_TRUE)
+      CEGLUtils::Log(LOGERROR, StringUtils::Format("failed to query EGL attribute %s", eglAttribute.second));
+
+    // we only need to print the hex value if it's an actual EGL define
+    CLog::Log(LOGDEBUG, "  %s: %s", eglAttribute.second, (value >= 0x3000 && value <= 0x3200) ? StringUtils::Format("0x%04x", value) : StringUtils::Format("%d", value));
+  }
+
+  return true;
+}
+
+EGLint CEGLContextUtils::GetConfigAttrib(EGLint attribute) const
+{
+  EGLint value{0};
+  if (eglGetConfigAttrib(m_eglDisplay, m_eglConfig, attribute, &value) != EGL_TRUE)
+    CEGLUtils::Log(LOGERROR, "failed to query EGL attribute");
+  return value;
+}
+
+bool CEGLContextUtils::CreateContext(CEGLAttributesVec contextAttribs)
+{
+  if (m_eglContext != EGL_NO_CONTEXT)
+  {
+    throw std::logic_error("Do not call CreateContext when context has already been created");
+  }
+
+  EGLConfig eglConfig{m_eglConfig};
+
+  if (CEGLUtils::HasExtension(m_eglDisplay, "EGL_KHR_no_config_context"))
+    eglConfig = EGL_NO_CONFIG_KHR;
+
+  if (CEGLUtils::HasExtension(m_eglDisplay, "EGL_IMG_context_priority"))
+    contextAttribs.Add({{EGL_CONTEXT_PRIORITY_LEVEL_IMG, EGL_CONTEXT_PRIORITY_HIGH_IMG}});
+
+//! @todo remove when Raspberry Pi updates their EGL headers
+#if !defined(TARGET_RASPBERRY_PI)
+  if (CEGLUtils::HasExtension(m_eglDisplay, "EGL_KHR_create_context") &&
+      CServiceBroker::GetSettingsComponent()->GetAdvancedSettings()->m_openGlDebugging)
+  {
+    contextAttribs.Add({{EGL_CONTEXT_FLAGS_KHR, EGL_CONTEXT_OPENGL_DEBUG_BIT_KHR}});
+  }
+#endif
+
+  m_eglContext = eglCreateContext(m_eglDisplay, eglConfig,
+                                  EGL_NO_CONTEXT, contextAttribs.Get());
+
+  if (CEGLUtils::HasExtension(m_eglDisplay, "EGL_IMG_context_priority"))
+  {
+    EGLint value{EGL_CONTEXT_PRIORITY_MEDIUM_IMG};
+
+    if (eglQueryContext(m_eglDisplay, m_eglContext, EGL_CONTEXT_PRIORITY_LEVEL_IMG, &value) != EGL_TRUE)
+      CEGLUtils::Log(LOGERROR, "failed to query EGL context attribute EGL_CONTEXT_PRIORITY_LEVEL_IMG");
+
+    if (value != EGL_CONTEXT_PRIORITY_HIGH_IMG)
+      CLog::Log(LOGDEBUG, "Failed to obtain a high priority EGL context");
+  }
+
+  if (m_eglContext == EGL_NO_CONTEXT)
+  {
+    // This is expected to fail under some circumstances, so log as debug
+    CLog::Log(LOGDEBUG, "Failed to create EGL context (EGL error %d)", eglGetError());
+    return false;
+  }
+
+  return true;
+}
+
+bool CEGLContextUtils::BindContext()
+{
+  if (m_eglDisplay == EGL_NO_DISPLAY || m_eglSurface == EGL_NO_SURFACE || m_eglContext == EGL_NO_CONTEXT)
+  {
+    throw std::logic_error("Activating an EGLContext requires display, surface, and context");
+  }
+
+  if (eglMakeCurrent(m_eglDisplay, m_eglSurface, m_eglSurface, m_eglContext) != EGL_TRUE)
+  {
+    CLog::Log(LOGERROR, "Failed to make context current %p %p %p",
+                         m_eglDisplay, m_eglSurface, m_eglContext);
+    return false;
+  }
+
+  return true;
+}
+
+void CEGLContextUtils::SurfaceAttrib()
+{
+  if (m_eglDisplay == EGL_NO_DISPLAY || m_eglSurface == EGL_NO_SURFACE)
+  {
+    throw std::logic_error("Setting surface attributes requires a surface");
+  }
+
+  // for the non-trivial dirty region modes, we need the EGL buffer to be preserved across updates
+  int guiAlgorithmDirtyRegions = CServiceBroker::GetSettingsComponent()->GetAdvancedSettings()->m_guiAlgorithmDirtyRegions;
+  if (guiAlgorithmDirtyRegions == DIRTYREGION_SOLVER_COST_REDUCTION ||
+      guiAlgorithmDirtyRegions == DIRTYREGION_SOLVER_UNION)
+  {
+    if (eglSurfaceAttrib(m_eglDisplay, m_eglSurface, EGL_SWAP_BEHAVIOR, EGL_BUFFER_PRESERVED) != EGL_TRUE)
+    {
+      CEGLUtils::Log(LOGERROR, "failed to set EGL_BUFFER_PRESERVED swap behavior");
+    }
+  }
+}
+
+void CEGLContextUtils::SurfaceAttrib(EGLint attribute, EGLint value)
+{
+  if (eglSurfaceAttrib(m_eglDisplay, m_eglSurface, attribute, value) != EGL_TRUE)
+  {
+    CEGLUtils::Log(LOGERROR, "failed to set EGL_BUFFER_PRESERVED swap behavior");
+  }
+}
+
+bool CEGLContextUtils::CreateSurface(EGLNativeWindowType nativeWindow, EGLint HDRcolorSpace /* = EGL_NONE */)
+{
+  if (m_eglDisplay == EGL_NO_DISPLAY)
+  {
+    throw std::logic_error("Creating a surface requires a display");
+  }
+  if (m_eglSurface != EGL_NO_SURFACE)
+  {
+    throw std::logic_error("Do not call CreateSurface when surface has already been created");
+  }
+
+  CEGLAttributesVec attribs;
+  EGLConfig config = m_eglConfig;
+
+#ifdef EGL_GL_COLORSPACE
+  if (HDRcolorSpace != EGL_NONE)
+  {
+    attribs.Add({{EGL_GL_COLORSPACE, HDRcolorSpace}});
+    config = m_eglHDRConfig;
+  }
+#endif
+
+  m_eglSurface = eglCreateWindowSurface(m_eglDisplay, config, nativeWindow, attribs.Get());
+
+  if (m_eglSurface == EGL_NO_SURFACE)
+  {
+    CEGLUtils::Log(LOGERROR, "failed to create window surface");
+    return false;
+  }
+
+  SurfaceAttrib();
+
+  return true;
+}
+
+bool CEGLContextUtils::CreatePlatformSurface(void* nativeWindow, EGLNativeWindowType nativeWindowLegacy)
+{
+  if (m_eglDisplay == EGL_NO_DISPLAY)
+  {
+    throw std::logic_error("Creating a surface requires a display");
+  }
+  if (m_eglSurface != EGL_NO_SURFACE)
+  {
+    throw std::logic_error("Do not call CreateSurface when surface has already been created");
+  }
+
+#if defined(EGL_EXT_platform_base)
+  if (IsPlatformSupported())
+  {
+    auto createPlatformWindowSurfaceEXT = CEGLUtils::GetRequiredProcAddress<PFNEGLCREATEPLATFORMWINDOWSURFACEEXTPROC>("eglCreatePlatformWindowSurfaceEXT");
+    m_eglSurface = createPlatformWindowSurfaceEXT(m_eglDisplay, m_eglConfig, nativeWindow, nullptr);
+
+    if (m_eglSurface == EGL_NO_SURFACE)
+    {
+      CEGLUtils::Log(LOGERROR, "failed to create platform window surface");
+      return false;
+    }
+  }
+#endif
+
+  if (m_eglSurface == EGL_NO_SURFACE)
+  {
+    return CreateSurface(nativeWindowLegacy);
+  }
+
+  SurfaceAttrib();
+
+  return true;
+}
+
+void CEGLContextUtils::Destroy()
+{
+  DestroyContext();
+  DestroySurface();
+
+  if (m_eglDisplay != EGL_NO_DISPLAY)
+  {
+    eglTerminate(m_eglDisplay);
+    m_eglDisplay = EGL_NO_DISPLAY;
+  }
+}
+
+void CEGLContextUtils::DestroyContext()
+{
+  if (m_eglContext != EGL_NO_CONTEXT)
+  {
+    eglMakeCurrent(m_eglDisplay, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
+    eglDestroyContext(m_eglDisplay, m_eglContext);
+    m_eglContext = EGL_NO_CONTEXT;
+  }
+}
+
+void CEGLContextUtils::DestroySurface()
+{
+  if (m_eglSurface != EGL_NO_SURFACE)
+  {
+    eglMakeCurrent(m_eglDisplay, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
+    eglDestroySurface(m_eglDisplay, m_eglSurface);
+    m_eglSurface = EGL_NO_SURFACE;
+  }
+}
+
+
+bool CEGLContextUtils::SetVSync(bool enable)
+{
+  if (m_eglDisplay == EGL_NO_DISPLAY)
+  {
+    return false;
+  }
+
+  return (eglSwapInterval(m_eglDisplay, enable) == EGL_TRUE);
+}
+
+bool CEGLContextUtils::TrySwapBuffers()
+{
+  if (m_eglDisplay == EGL_NO_DISPLAY || m_eglSurface == EGL_NO_SURFACE)
+  {
+    return false;
+  }
+
+  return (eglSwapBuffers(m_eglDisplay, m_eglSurface) == EGL_TRUE);
+}