Corrected OpenGL extension detection

- corrected multitexture and VBO detection
- GLEW is now a required library
- minor CMakeLists refactoring

CMakeLists.txt

@@ -20,14 +20,14 @@ set(COLOBOT_VERSION_UNRELEASED "~pre-alpha")
 
 # Append git characteristics to version
 if(DEFINED COLOBOT_VERSION_UNRELEASED AND EXISTS "${CMAKE_SOURCE_DIR}/.git")
-	find_package(Git)
+    find_package(Git)
-	execute_process(COMMAND ${GIT_EXECUTABLE} rev-parse --abbrev-ref HEAD
+    execute_process(COMMAND ${GIT_EXECUTABLE} rev-parse --abbrev-ref HEAD
-			OUTPUT_VARIABLE GIT_BRANCH
+                    OUTPUT_VARIABLE GIT_BRANCH
-			OUTPUT_STRIP_TRAILING_WHITESPACE)
+                    OUTPUT_STRIP_TRAILING_WHITESPACE)
-	execute_process(COMMAND ${GIT_EXECUTABLE} rev-parse --short HEAD
+    execute_process(COMMAND ${GIT_EXECUTABLE} rev-parse --short HEAD
-			OUTPUT_VARIABLE GIT_REVISION
+                    OUTPUT_VARIABLE GIT_REVISION
-			OUTPUT_STRIP_TRAILING_WHITESPACE)
+                    OUTPUT_STRIP_TRAILING_WHITESPACE)
-	set(COLOBOT_VERSION_UNRELEASED "${COLOBOT_VERSION_UNRELEASED}-git-${GIT_BRANCH}~r${GIT_REVISION}")
+    set(COLOBOT_VERSION_UNRELEASED "${COLOBOT_VERSION_UNRELEASED}-git-${GIT_BRANCH}~r${GIT_REVISION}")
 endif()
 
 set(COLOBOT_VERSION_FULL "${COLOBOT_VERSION_MAJOR}.${COLOBOT_VERSION_MINOR}.${COLOBOT_VERSION_REVISION}${COLOBOT_VERSION_UNRELEASED}")
@@ -67,6 +67,7 @@ option(INSTALL_DOCS "Install Doxygen-generated documentation" OFF)
 # Build openal sound support
 option(OPENAL_SOUND "Build openal sound support" OFF)
 
+
 ##
 # Required packages
 ##
@@ -85,17 +86,11 @@ set(Boost_USE_STATIC_RUNTIME    OFF)
 set(Boost_ADDITIONALVERSION "1.51" "1.51.0")
 find_package(Boost COMPONENTS system filesystem regex REQUIRED)
 
-# GLEW requirement depends on platform
-# By default it is auto detected
-# This setting may be used to override
-# Possible values:
-# - auto -> determine automatically
-# - 1 -> always enable
-# - 0 -> always disable
-set(USE_GLEW auto)
 # This is useful on Windows, if linking against standard GLEW dll fails
 option(GLEW_STATIC "Link statically with GLEW" OFF)
 
+find_package(GLEW REQUIRED)
+
 
 ##
 # Additional settings to use when cross-compiling with MXE (http://mxe.cc/)
@@ -113,38 +108,19 @@ if (${CMAKE_SYSTEM_NAME} MATCHES "Windows")
     set(PLATFORM_WINDOWS 1)
     set(PLATFORM_LINUX   0)
     set(PLATFORM_OTHER   0)
-
-    # On Windows, GLEW is required
-    if (${USE_GLEW} MATCHES "auto")
-        set(USE_GLEW 1)
-    endif()
 elseif(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
     message(STATUS "Linux system detected")
     set(PLATFORM_WINDOWS 0)
     set(PLATFORM_LINUX   1)
     set(PLATFORM_OTHER   0)
-
-    # On Linux, we should be fine without GLEW
-    if (${USE_GLEW} MATCHES "auto")
-        set(USE_GLEW 0)
-    endif()
 else()
     message(STATUS "Other system detected")
     set(PLATFORM_WINDOWS 0)
     set(PLATFORM_LINUX   0)
     set(PLATFORM_OTHER   1)
-
-    # Use GLEW to be safe
-    if (${USE_GLEW} MATCHES "auto")
-        set(USE_GLEW 1)
-    endif()
 endif()
 
 
-if(${USE_GLEW})
-    find_package(GLEW REQUIRED)
-endif()
-
 if(NOT ${ASSERTS})
     add_definitions(-DNDEBUG)
 endif()

src/CMakeLists.txt

@@ -19,32 +19,24 @@ endif()
 
 # Optional libraries
 set(OPTIONAL_LIBS "")
-set(OPTIONAL_INCLUDE_DIRS "")
-
-if(${USE_GLEW} AND NOT ${MXE})
-    set(OPTIONAL_LIBS ${OPTIONAL_LIBS} ${GLEW_LIBRARY})
-    set(OPTIONAL_INCLUDE_DIRS ${OPTIONAL_INCLUDE_DIRS} ${GLEW_INCLUDE_PATH})
-endif()
-
-
-# Additional libraries per platform
-set(PLATFORM_LIBS "")
-set(OPENAL_LIBS "")
 
 if (${OPENAL_SOUND})
     if (${MXE})
-	set(OPENAL_LIBS
+        set(OPTIONAL_LIBS
-	    ${CMAKE_FIND_ROOT_PATH}/lib/libOpenAL32.a
+            ${CMAKE_FIND_ROOT_PATH}/lib/libOpenAL32.a
-	    ${CMAKE_FIND_ROOT_PATH}/lib/libalut.a
+            ${CMAKE_FIND_ROOT_PATH}/lib/libalut.a
-	)
+        )
     else()
-	set(OPENAL_LIBS
+        set(OPTIONAL_LIBS
-	    openal
+            openal
-	    alut
+            alut
-	)
+        )
     endif()
 endif()
 
+# Additional libraries per platform
+set(PLATFORM_LIBS "")
+
 if (${MXE}) # MXE requires special treatment
     set(PLATFORM_LIBS ${MXE_LIBS})  
 elseif (${PLATFORM_WINDOWS})
@@ -63,9 +55,9 @@ set(OPENAL_SRC "")
 
 if (${OPENAL_SOUND})
     set(OPENAL_SRC
-	sound/oalsound/alsound.cpp
+        sound/oalsound/alsound.cpp
-	sound/oalsound/buffer.cpp
+        sound/oalsound/buffer.cpp
-	sound/oalsound/channel.cpp
+        sound/oalsound/channel.cpp
     )
 endif()
 
@@ -192,16 +184,16 @@ ${OPENAL_SRC}
 
 
 set(LIBS
+CBot
 ${SDL_LIBRARY}
 ${SDLIMAGE_LIBRARY}
 ${SDLTTF_LIBRARY}
 ${OPENGL_LIBRARY}
 ${PNG_LIBRARIES}
+${GLEW_LIBRARY}
+${Boost_LIBRARIES}
 ${OPTIONAL_LIBS}
 ${PLATFORM_LIBS}
-${Boost_LIBRARIES}
-CBot
-${OPENAL_LIBS}
 )
 
 include_directories(
@@ -212,8 +204,9 @@ ${SDL_INCLUDE_DIR}
 ${SDLIMAGE_INCLUDE_DIR}
 ${SDLTTF_INCLUDE_DIR}
 ${PNG_INCLUDE_DIRS}
-${OPTIONAL_INCLUDE_DIRS}
+${GLEW_INCLUDE_PATH}
 ${Boost_INCLUDE_DIRS}
+${OPTIONAL_INCLUDE_DIRS}
 )
 
 link_directories(${CMAKE_CURRENT_SOURCE_DIR}/CBot)

src/app/app.cpp

@@ -264,7 +264,6 @@ ParseArgsStatus CApplication::ParseArguments(int argc, char *argv[])
             GetLogger()->Message("\n");
             GetLogger()->Message("List of available options:\n");
             GetLogger()->Message("  -help            this help\n");
-            GetLogger()->Message("  -vbo             enable OpenGL VBOs\n");
             GetLogger()->Message("  -datadir path    set custom data directory path\n");
             GetLogger()->Message("  -debug           enable debug mode (more info printed in logs)\n");
             GetLogger()->Message("  -loglevel level  set log level to level (one of: trace, debug, info, warn, error, none)\n");

src/common/config.h.cmake

@@ -5,7 +5,6 @@
 #cmakedefine PLATFORM_LINUX @PLATFORM_LINUX@
 #cmakedefine PLATFORM_OTHER @PLATFORM_OTHER@
 
-#cmakedefine USE_GLEW @USE_GLEW@
 #cmakedefine GLEW_STATIC
 
 #define COLOBOT_VERSION "@COLOBOT_VERSION_FULL@"

src/graphics/core/device.h

@@ -104,8 +104,7 @@ enum RenderState
     RENDER_STATE_DEPTH_TEST,
     RENDER_STATE_DEPTH_WRITE,
     RENDER_STATE_ALPHA_TEST,
-    RENDER_STATE_CULLING,
+    RENDER_STATE_CULLING
-    RENDER_STATE_DITHERING
 };
 
 /**
@@ -287,7 +286,7 @@ public:
     virtual void DestroyAllTextures() = 0;
 
     //! Returns the maximum number of multitexture stages
-    virtual int GetMaxTextureCount() = 0;
+    virtual int GetMaxTextureStageCount() = 0;
     //! Sets the texture at given texture stage
     virtual void SetTexture(int index, const Texture &texture) = 0;
     //! Sets the texture image by ID at given texture stage

src/graphics/opengl/gldevice.cpp

@@ -24,22 +24,9 @@
 #include "math/geometry.h"
 
 
-#if defined(USE_GLEW)
+// Using GLEW so only glew.h is needed
-
-// When using GLEW, only glew.h is needed
 #include <GL/glew.h>
 
-#else
-
-// Should define prototypes of used extensions as OpenGL functions
-#define GL_GLEXT_PROTOTYPES
-
-#include <GL/gl.h>
-#include <GL/glu.h>
-#include <GL/glext.h>
-
-#endif // if defined(GLEW)
-
 #include <SDL/SDL.h>
 
 #include <cassert>
@@ -74,7 +61,8 @@ CGLDevice::CGLDevice(const GLDeviceConfig &config)
     m_config = config;
     m_lighting = false;
     m_lastVboId = 0;
-    m_useVbo = false;
+    m_multitextureAvailable = false;
+    m_vboAvailable = false;
 }
 
 
@@ -93,7 +81,6 @@ bool CGLDevice::Create()
 {
     GetLogger()->Info("Creating CDevice\n");
 
-#if defined(USE_GLEW)
     static bool glewInited = false;
 
     if (!glewInited)
@@ -106,26 +93,16 @@ bool CGLDevice::Create()
             return false;
         }
 
-        if ( (! GLEW_ARB_multitexture) || (! GLEW_EXT_texture_env_combine) )
+        m_multitextureAvailable = glewIsSupported("GL_ARB_multitexture GL_ARB_texture_env_combine");
-        {
+        if (!m_multitextureAvailable)
-            GetLogger()->Error("GLEW reports required extensions not supported\n");
+            GetLogger()->Error("GLEW reports multitexturing not supported - graphics quality will be degraded!\n");
-            return false;
-        }
 
-        if (GLEW_ARB_vertex_buffer_object)
+        m_vboAvailable = glewIsSupported("GL_ARB_vertex_buffer_object");
-        {
+        if (m_vboAvailable)
             GetLogger()->Info("Detected ARB_vertex_buffer_object extension - using VBOs\n");
-            m_useVbo = true;
-        }
         else
-        {
             GetLogger()->Info("No ARB_vertex_buffer_object extension present - using display lists\n");
-        }
     }
-#endif
-
-    /* NOTE: when not using GLEW, extension testing is not performed, as it is assumed that
-             glext.h is up-to-date and the OpenGL shared library has the required functions present. */
 
     // This is mostly done in all modern hardware by default
     // DirectX doesn't even allow the option to turn off perspective correction anymore
@@ -135,6 +112,9 @@ bool CGLDevice::Create()
     // To avoid problems with scaling & lighting
     glEnable(GL_RESCALE_NORMAL);
 
+    // Minimal depth bias to avoid Z-fighting
+    SetDepthBias(0.001f);
+
     // Set just to be sure
     glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
     glMatrixMode(GL_PROJECTION);
@@ -186,14 +166,14 @@ void CGLDevice::ConfigChanged(const GLDeviceConfig& newConfig)
     Create();
 }
 
-void CGLDevice::SetUseVbo(bool useVbo)
+void CGLDevice::SetUseVbo(bool vboAvailable)
 {
-    m_useVbo = useVbo;
+    m_vboAvailable = vboAvailable;
 }
 
 bool CGLDevice::GetUseVbo()
 {
-    return m_useVbo;
+    return m_vboAvailable;
 }
 
 void CGLDevice::BeginScene()
@@ -610,7 +590,7 @@ void CGLDevice::DestroyAllTextures()
     m_allTextures.clear();
 }
 
-int CGLDevice::GetMaxTextureCount()
+int CGLDevice::GetMaxTextureStageCount()
 {
     return m_currentTextures.size();
 }
@@ -621,17 +601,21 @@ int CGLDevice::GetMaxTextureCount()
   The setting is remembered, even if texturing is disabled at the moment. */
 void CGLDevice::SetTexture(int index, const Texture &texture)
 {
-    assert(index >= 0);
+    assert(index >= 0 && index < static_cast<int>( m_currentTextures.size() ));
-    assert(index < static_cast<int>( m_currentTextures.size() ));
 
     bool same = m_currentTextures[index].id == texture.id;
 
     m_currentTextures[index] = texture; // remember the new value
 
+    if (!m_multitextureAvailable && index != 0)
+        return;
+
     if (same)
         return; // nothing to do
 
-    glActiveTexture(GL_TEXTURE0 + index);
+    if (m_multitextureAvailable)
+        glActiveTexture(GL_TEXTURE0 + index);
+
     glBindTexture(GL_TEXTURE_2D, texture.id);
 
     // Params need to be updated for the new bound texture
@@ -640,15 +624,19 @@ void CGLDevice::SetTexture(int index, const Texture &texture)
 
 void CGLDevice::SetTexture(int index, unsigned int textureId)
 {
-    assert(index >= 0);
+    assert(index >= 0 && index < static_cast<int>( m_currentTextures.size() ));
-    assert(index < static_cast<int>( m_currentTextures.size() ));
 
     if (m_currentTextures[index].id == textureId)
         return; // nothing to do
 
     m_currentTextures[index].id = textureId;
 
-    glActiveTexture(GL_TEXTURE0 + index);
+    if (!m_multitextureAvailable && index != 0)
+        return;
+
+    if (m_multitextureAvailable)
+        glActiveTexture(GL_TEXTURE0 + index);
+
     glBindTexture(GL_TEXTURE_2D, textureId);
 
     // Params need to be updated for the new bound texture
@@ -659,16 +647,14 @@ void CGLDevice::SetTexture(int index, unsigned int textureId)
   Returns the previously assigned texture or invalid texture if the given stage is not enabled. */
 Texture CGLDevice::GetTexture(int index)
 {
-    assert(index >= 0);
+    assert(index >= 0 && index < static_cast<int>( m_currentTextures.size() ));
-    assert(index < static_cast<int>( m_currentTextures.size() ));
 
     return m_currentTextures[index];
 }
 
 void CGLDevice::SetTextureEnabled(int index, bool enabled)
 {
-    assert(index >= 0);
+    assert(index >= 0 && index < static_cast<int>( m_currentTextures.size() ));
-    assert(index < static_cast<int>( m_currentTextures.size() ));
 
     bool same = m_texturesEnabled[index] == enabled;
 
@@ -677,7 +663,12 @@ void CGLDevice::SetTextureEnabled(int index, bool enabled)
     if (same)
         return; // nothing to do
 
-    glActiveTexture(GL_TEXTURE0 + index);
+    if (!m_multitextureAvailable && index != 0)
+        return;
+
+    if (m_multitextureAvailable)
+        glActiveTexture(GL_TEXTURE0 + index);
+
     if (enabled)
         glEnable(GL_TEXTURE_2D);
     else
@@ -686,8 +677,7 @@ void CGLDevice::SetTextureEnabled(int index, bool enabled)
 
 bool CGLDevice::GetTextureEnabled(int index)
 {
-    assert(index >= 0);
+    assert(index >= 0 && index < static_cast<int>( m_currentTextures.size() ));
-    assert(index < static_cast<int>( m_currentTextures.size() ));
 
     return m_texturesEnabled[index];
 }
@@ -698,17 +688,36 @@ bool CGLDevice::GetTextureEnabled(int index)
   The settings are remembered, even if texturing is disabled at the moment. */
 void CGLDevice::SetTextureStageParams(int index, const TextureStageParams &params)
 {
-    assert(index >= 0);
+    assert(index >= 0 && index < static_cast<int>( m_currentTextures.size() ));
-    assert(index < static_cast<int>( m_currentTextures.size() ));
 
     // Remember the settings
     m_textureStageParams[index] = params;
 
+    if (!m_multitextureAvailable && index != 0)
+        return;
+
     // Don't actually do anything if texture not set
     if (! m_currentTextures[index].Valid())
         return;
 
-    glActiveTexture(GL_TEXTURE0 + index);
+    if (m_multitextureAvailable)
+        glActiveTexture(GL_TEXTURE0 + index);
+
+    if      (params.wrapS == TEX_WRAP_CLAMP)
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
+    else if (params.wrapS == TEX_WRAP_REPEAT)
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+    else  assert(false);
+
+    if      (params.wrapT == TEX_WRAP_CLAMP)
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
+    else if (params.wrapT == TEX_WRAP_REPEAT)
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+    else  assert(false);
+
+    // Texture env setting is silly without multitexturing
+    if (!m_multitextureAvailable)
+        return;
 
     glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, params.factor.Array());
 
@@ -812,26 +821,12 @@ after_tex_color:
         glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE1_ALPHA, GL_CONSTANT);
     else  assert(false);
 
-
+after_tex_operations: ;
-after_tex_operations:
-
-    if      (params.wrapS == TEX_WRAP_CLAMP)
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
-    else if (params.wrapS == TEX_WRAP_REPEAT)
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-    else  assert(false);
-
-    if      (params.wrapT == TEX_WRAP_CLAMP)
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
-    else if (params.wrapT == TEX_WRAP_REPEAT)
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-    else  assert(false);
 }
 
 void CGLDevice::SetTextureStageWrap(int index, TexWrapMode wrapS, TexWrapMode wrapT)
 {
-    assert(index >= 0);
+    assert(index >= 0 && index < static_cast<int>( m_currentTextures.size() ));
-    assert(index < static_cast<int>( m_currentTextures.size() ));
 
     // Remember the settings
     m_textureStageParams[index].wrapS = wrapS;
@@ -841,7 +836,11 @@ void CGLDevice::SetTextureStageWrap(int index, TexWrapMode wrapS, TexWrapMode wr
     if (! m_currentTextures[index].Valid())
         return;
 
-    glActiveTexture(GL_TEXTURE0 + index);
+    if (!m_multitextureAvailable && index != 0)
+        return;
+
+    if (m_multitextureAvailable)
+        glActiveTexture(GL_TEXTURE0 + index);
 
     if      (wrapS == TEX_WRAP_CLAMP)
         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
@@ -858,8 +857,7 @@ void CGLDevice::SetTextureStageWrap(int index, TexWrapMode wrapS, TexWrapMode wr
 
 TextureStageParams CGLDevice::GetTextureStageParams(int index)
 {
-    assert(index >= 0);
+    assert(index >= 0 && index < static_cast<int>( m_currentTextures.size() ));
-    assert(index < static_cast<int>( m_currentTextures.size() ));
 
     return m_textureStageParams[index];
 }
@@ -890,7 +888,9 @@ void CGLDevice::DrawPrimitive(PrimitiveType type, const Vertex *vertices, int ve
     glEnableClientState(GL_NORMAL_ARRAY);
     glNormalPointer(GL_FLOAT, sizeof(Vertex), reinterpret_cast<GLfloat*>(&vs[0].normal));
 
-    glClientActiveTexture(GL_TEXTURE0);
+    if (m_multitextureAvailable)
+        glClientActiveTexture(GL_TEXTURE0);
+
     glEnableClientState(GL_TEXTURE_COORD_ARRAY);
     glTexCoordPointer(2, GL_FLOAT, sizeof(Vertex), reinterpret_cast<GLfloat*>(&vs[0].texCoord));
 
@@ -914,13 +914,18 @@ void CGLDevice::DrawPrimitive(PrimitiveType type, const VertexTex2 *vertices, in
     glEnableClientState(GL_NORMAL_ARRAY);
     glNormalPointer(GL_FLOAT, sizeof(VertexTex2), reinterpret_cast<GLfloat*>(&vs[0].normal));
 
-    glClientActiveTexture(GL_TEXTURE0);
+    if (m_multitextureAvailable)
+        glClientActiveTexture(GL_TEXTURE0);
+
     glEnableClientState(GL_TEXTURE_COORD_ARRAY);
     glTexCoordPointer(2, GL_FLOAT, sizeof(VertexTex2), reinterpret_cast<GLfloat*>(&vs[0].texCoord));
 
-    glClientActiveTexture(GL_TEXTURE1);
+    if (m_multitextureAvailable)
-    glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+    {
-    glTexCoordPointer(2, GL_FLOAT, sizeof(VertexTex2), reinterpret_cast<GLfloat*>(&vs[0].texCoord2));
+        glClientActiveTexture(GL_TEXTURE1);
+        glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+        glTexCoordPointer(2, GL_FLOAT, sizeof(VertexTex2), reinterpret_cast<GLfloat*>(&vs[0].texCoord2));
+    }
 
     glColor4fv(color.Array());
 
@@ -929,8 +934,11 @@ void CGLDevice::DrawPrimitive(PrimitiveType type, const VertexTex2 *vertices, in
     glDisableClientState(GL_VERTEX_ARRAY);
     glDisableClientState(GL_NORMAL_ARRAY);
     glDisableClientState(GL_TEXTURE_COORD_ARRAY); // GL_TEXTURE1
-    glClientActiveTexture(GL_TEXTURE0);
+    if (m_multitextureAvailable)
-    glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+    {
+        glClientActiveTexture(GL_TEXTURE0);
+        glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+    }
 }
 
 void CGLDevice::DrawPrimitive(PrimitiveType type, const VertexCol *vertices, int vertexCount)
@@ -952,7 +960,7 @@ void CGLDevice::DrawPrimitive(PrimitiveType type, const VertexCol *vertices, int
 unsigned int CGLDevice::CreateStaticBuffer(PrimitiveType primitiveType, const Vertex* vertices, int vertexCount)
 {
     unsigned int id = 0;
-    if (m_useVbo)
+    if (m_vboAvailable)
     {
         id = ++m_lastVboId;
 
@@ -986,7 +994,7 @@ unsigned int CGLDevice::CreateStaticBuffer(PrimitiveType primitiveType, const Ve
 unsigned int CGLDevice::CreateStaticBuffer(PrimitiveType primitiveType, const VertexTex2* vertices, int vertexCount)
 {
     unsigned int id = 0;
-    if (m_useVbo)
+    if (m_vboAvailable)
     {
         id = ++m_lastVboId;
 
@@ -1020,7 +1028,7 @@ unsigned int CGLDevice::CreateStaticBuffer(PrimitiveType primitiveType, const Ve
 unsigned int CGLDevice::CreateStaticBuffer(PrimitiveType primitiveType, const VertexCol* vertices, int vertexCount)
 {
     unsigned int id = 0;
-    if (m_useVbo)
+    if (m_vboAvailable)
     {
         id = ++m_lastVboId;
 
@@ -1053,7 +1061,7 @@ unsigned int CGLDevice::CreateStaticBuffer(PrimitiveType primitiveType, const Ve
 
 void CGLDevice::UpdateStaticBuffer(unsigned int bufferId, PrimitiveType primitiveType, const Vertex* vertices, int vertexCount)
 {
-    if (m_useVbo)
+    if (m_vboAvailable)
     {
         auto it = m_vboObjects.find(bufferId);
         if (it == m_vboObjects.end())
@@ -1080,7 +1088,7 @@ void CGLDevice::UpdateStaticBuffer(unsigned int bufferId, PrimitiveType primitiv
 
 void CGLDevice::UpdateStaticBuffer(unsigned int bufferId, PrimitiveType primitiveType, const VertexTex2* vertices, int vertexCount)
 {
-    if (m_useVbo)
+    if (m_vboAvailable)
     {
         auto it = m_vboObjects.find(bufferId);
         if (it == m_vboObjects.end())
@@ -1107,7 +1115,7 @@ void CGLDevice::UpdateStaticBuffer(unsigned int bufferId, PrimitiveType primitiv
 
 void CGLDevice::UpdateStaticBuffer(unsigned int bufferId, PrimitiveType primitiveType, const VertexCol* vertices, int vertexCount)
 {
-    if (m_useVbo)
+    if (m_vboAvailable)
     {
         auto it = m_vboObjects.find(bufferId);
         if (it == m_vboObjects.end())
@@ -1134,7 +1142,7 @@ void CGLDevice::UpdateStaticBuffer(unsigned int bufferId, PrimitiveType primitiv
 
 void CGLDevice::DrawStaticBuffer(unsigned int bufferId)
 {
-    if (m_useVbo)
+    if (m_vboAvailable)
     {
         auto it = m_vboObjects.find(bufferId);
         if (it == m_vboObjects.end())
@@ -1151,7 +1159,9 @@ void CGLDevice::DrawStaticBuffer(unsigned int bufferId)
             glEnableClientState(GL_NORMAL_ARRAY);
             glNormalPointer(GL_FLOAT, sizeof(Vertex), static_cast<char*>(nullptr) + offsetof(Vertex, normal));
 
-            glClientActiveTexture(GL_TEXTURE0);
+            if (m_multitextureAvailable)
+                glClientActiveTexture(GL_TEXTURE0);
+
             glEnableClientState(GL_TEXTURE_COORD_ARRAY);
             glTexCoordPointer(2, GL_FLOAT, sizeof(Vertex), static_cast<char*>(nullptr) + offsetof(Vertex, texCoord));
         }
@@ -1163,13 +1173,18 @@ void CGLDevice::DrawStaticBuffer(unsigned int bufferId)
             glEnableClientState(GL_NORMAL_ARRAY);
             glNormalPointer(GL_FLOAT, sizeof(VertexTex2), static_cast<char*>(nullptr) + offsetof(VertexTex2, normal));
 
-            glClientActiveTexture(GL_TEXTURE0);
+            if (m_multitextureAvailable)
+                glClientActiveTexture(GL_TEXTURE0);
+
             glEnableClientState(GL_TEXTURE_COORD_ARRAY);
             glTexCoordPointer(2, GL_FLOAT, sizeof(VertexTex2), static_cast<char*>(nullptr) + offsetof(VertexTex2, texCoord));
 
-            glClientActiveTexture(GL_TEXTURE1);
+            if (m_multitextureAvailable)
-            glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+            {
-            glTexCoordPointer(2, GL_FLOAT, sizeof(VertexTex2), static_cast<char*>(nullptr) + offsetof(VertexTex2, texCoord2));
+                glClientActiveTexture(GL_TEXTURE1);
+                glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+                glTexCoordPointer(2, GL_FLOAT, sizeof(VertexTex2), static_cast<char*>(nullptr) + offsetof(VertexTex2, texCoord2));
+            }
         }
         else if ((*it).second.vertexType == VERTEX_TYPE_COL)
         {
@@ -1194,8 +1209,11 @@ void CGLDevice::DrawStaticBuffer(unsigned int bufferId)
             glDisableClientState(GL_VERTEX_ARRAY);
             glDisableClientState(GL_NORMAL_ARRAY);
             glDisableClientState(GL_TEXTURE_COORD_ARRAY); // GL_TEXTURE1
-            glClientActiveTexture(GL_TEXTURE0);
+            if (m_multitextureAvailable)
-            glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+            {
+                glClientActiveTexture(GL_TEXTURE0);
+                glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+            }
         }
         else if ((*it).second.vertexType == VERTEX_TYPE_COL)
         {
@@ -1214,7 +1232,7 @@ void CGLDevice::DrawStaticBuffer(unsigned int bufferId)
 
 void CGLDevice::DestroyStaticBuffer(unsigned int bufferId)
 {
-    if (m_useVbo)
+    if (m_vboAvailable)
     {
         auto it = m_vboObjects.find(bufferId);
         if (it == m_vboObjects.end())
@@ -1355,7 +1373,6 @@ void CGLDevice::SetRenderState(RenderState state, bool enabled)
         case RENDER_STATE_DEPTH_TEST:  flag = GL_DEPTH_TEST; break;
         case RENDER_STATE_ALPHA_TEST:  flag = GL_ALPHA_TEST; break;
         case RENDER_STATE_CULLING:     flag = GL_CULL_FACE; break;
-        case RENDER_STATE_DITHERING:   flag = GL_DITHER; break;
         default: assert(false); break;
     }
 
@@ -1380,7 +1397,6 @@ bool CGLDevice::GetRenderState(RenderState state)
         case RENDER_STATE_DEPTH_TEST:  flag = GL_DEPTH_TEST; break;
         case RENDER_STATE_ALPHA_TEST:  flag = GL_ALPHA_TEST; break;
         case RENDER_STATE_CULLING:     flag = GL_CULL_FACE; break;
-        case RENDER_STATE_DITHERING:   flag = GL_DITHER; break;
         default: assert(false); break;
     }
 

src/graphics/opengl/gldevice.h

@@ -111,7 +111,7 @@ public:
     virtual void DestroyTexture(const Texture &texture);
     virtual void DestroyAllTextures();
 
-    virtual int GetMaxTextureCount();
+    virtual int GetMaxTextureStageCount();
     virtual void SetTexture(int index, const Texture &texture);
     virtual void SetTexture(int index, unsigned int textureId);
     virtual Texture GetTexture(int index);
@@ -229,8 +229,10 @@ private:
         int vertexCount;
     };
 
+    //! Whether to use multitexturing
+    bool m_multitextureAvailable;
     //! Whether to use VBOs or display lists
-    bool m_useVbo;
+    bool m_vboAvailable;
     //! Map of saved VBO objects
     std::map<unsigned int, VboObjectInfo> m_vboObjects;
     //! Last ID of VBO object