Multitexturing support

- added CImage class for loading/saving images and a simple test for it
- added libpng library to build
- added Gfx::Texture struct
- updated the Gfx::CDevice interface to include new features
- implemented the new features in Gfx::CGLDevice

10 files changed, 981 insertions, 66 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 1be7a59..a02e7b9 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -30,6 +30,7 @@ app/app.cpp
 app/main.cpp
 app/system.cpp
 common/event.cpp
+common/image.cpp
 common/iman.cpp
 # common/metafile.cpp
 # common/misc.cpp
@@ -150,10 +151,16 @@ set(LIBS
 ${SDL_LIBRARY}
 ${SDLIMAGE_LIBRARY}
 ${OPENGL_LIBRARY}
+${PNG_LIBRARIES}
 #CBot  -- not yet WinAPI-independent
 )
 
-include_directories(. ${CMAKE_CURRENT_BINARY_DIR})
+include_directories(. ${CMAKE_CURRENT_BINARY_DIR}
+${SDL_INCLUDE_DIR}
+${SDL_IMAGE_INCLUDE_DIR}
+${SDLTTF_INCLUDE_DIR}
+${PNG_INCLUDE_DIRS}
+)
 
 link_directories(${CMAKE_CURRENT_SOURCE_DIR}/CBot)
 
diff --git a/src/common/image.cpp b/src/common/image.cpp
new file mode 100644
index 0000000..78834b4
--- /dev/null
+++ b/src/common/image.cpp
@@ -0,0 +1,221 @@
+// * This file is part of the COLOBOT source code
+// * Copyright (C) 2012, Polish Portal of Colobot (PPC)
+// *
+// * This program is free software: you can redistribute it and/or modify
+// * it under the terms of the GNU General Public License as published by
+// * the Free Software Foundation, either version 3 of the License, or
+// * (at your option) any later version.
+// *
+// * This program is distributed in the hope that it will be useful,
+// * but WITHOUT ANY WARRANTY; without even the implied warranty of
+// * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// * GNU General Public License for more details.
+// *
+// * You should have received a copy of the GNU General Public License
+// * along with this program. If not, see  http://www.gnu.org/licenses/.
+
+// image.cpp
+
+#include "image.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <SDL/SDL.h>
+#include <SDL/SDL_image.h>
+#include <png.h>
+
+
+/* <---------------------------------------------------------------> */
+
+/* The following code is from savesurf program by Angelo "Encelo" Theodorou
+   Source: http://encelo.netsons.org/old/sdl/
+   The code was refactored and modified slightly to fit the needs.
+   The copyright information below is kept unchanged. */
+
+
+/* SaveSurf: an example on how to save a SDLSurface in PNG
+   Copyright (C) 2006 Angelo "Encelo" Theodorou
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+   NOTE:
+
+   This program is part of "Mars, Land of No Mercy" SDL examples,
+   you can find other examples on http://marsnomercy.org
+*/
+
+std::string PNG_ERROR = "";
+
+void PNGUserError(png_structp ctx, png_const_charp str)
+{
+    PNG_ERROR = std::string(str);
+}
+
+int PNGColortypeFromSurface(SDL_Surface *surface)
+{
+    int colortype = PNG_COLOR_MASK_COLOR; /* grayscale not supported */
+
+    if (surface->format->palette)
+        colortype |= PNG_COLOR_MASK_PALETTE;
+    else if (surface->format->Amask)
+        colortype |= PNG_COLOR_MASK_ALPHA;
+
+    return colortype;
+}
+
+bool PNGSaveSurface(const char *filename, SDL_Surface *surf)
+{
+    FILE *fp;
+    png_structp png_ptr;
+    png_infop info_ptr;
+    int i, colortype;
+    png_bytep *row_pointers;
+
+    PNG_ERROR = "";
+
+    /* Opening output file */
+    fp = fopen(filename, "wb");
+    if (fp == NULL)
+    {
+        PNG_ERROR = std::string("Could not open file '") + std::string(filename) + std::string("' for saving");
+        return false;
+    }
+
+    /* Initializing png structures and callbacks */
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, PNGUserError, NULL);
+    if (png_ptr == NULL)
+        return false;
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (info_ptr == NULL)
+    {
+        png_destroy_write_struct(&png_ptr, (png_infopp)NULL);
+        PNG_ERROR = "png_create_info_struct() error!";
+        return false;
+    }
+
+    if (setjmp(png_jmpbuf(png_ptr))) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        fclose(fp);
+        return false;
+    }
+
+    png_init_io(png_ptr, fp);
+
+    colortype = PNGColortypeFromSurface(surf);
+    png_set_IHDR(png_ptr, info_ptr, surf->w, surf->h, 8, colortype, PNG_INTERLACE_NONE,
+                 PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
+
+    /* Writing the image */
+    png_write_info(png_ptr, info_ptr);
+    png_set_packing(png_ptr);
+
+    row_pointers = (png_bytep*) malloc(sizeof(png_bytep)*surf->h);
+    for (i = 0; i < surf->h; i++)
+        row_pointers[i] = (png_bytep)(Uint8 *)surf->pixels + i*surf->pitch;
+    png_write_image(png_ptr, row_pointers);
+    png_write_end(png_ptr, info_ptr);
+
+    /* Cleaning out... */
+    free(row_pointers);
+    png_destroy_write_struct(&png_ptr, &info_ptr);
+    fclose(fp);
+
+    return true;
+}
+
+/* <---------------------------------------------------------------> */
+
+
+CImage::CImage()
+{
+    m_data = NULL;
+}
+
+CImage::~CImage()
+{
+    Free();
+}
+
+bool CImage::IsEmpty()
+{
+    return m_data == NULL;
+}
+
+void CImage::Free()
+{
+    if (m_data != NULL)
+    {
+        if (m_data->surface != NULL)
+        {
+            SDL_FreeSurface(m_data->surface);
+            m_data->surface = NULL;
+        }
+        delete m_data;
+        m_data = NULL;
+    }
+}
+
+ImageData* CImage::GetData()
+{
+    return m_data;
+}
+
+std::string CImage::GetError()
+{
+    return m_error;
+}
+
+bool CImage::Load(const std::string& fileName)
+{
+    if (! IsEmpty() )
+        Free();
+
+    m_data = new ImageData();
+
+    m_error = "";
+
+    m_data->surface = IMG_Load(fileName.c_str());
+    if (m_data->surface == NULL)
+    {
+        delete m_data;
+        m_data = NULL;
+
+        m_error = std::string(IMG_GetError());
+        return false;
+    }
+
+    return true;
+}
+
+bool CImage::SavePNG(const std::string& fileName)
+{
+    if (IsEmpty())
+    {
+        m_error = "Empty image!";
+        return false;
+    }
+
+    m_error = "";
+
+    if (! PNGSaveSurface(fileName.c_str(), m_data->surface) )
+    {
+        m_error = PNG_ERROR;
+        return false;
+    }
+
+    return true;
+}
diff --git a/src/common/image.h b/src/common/image.h
new file mode 100644
index 0000000..4d86d31
--- /dev/null
+++ b/src/common/image.h
@@ -0,0 +1,84 @@
+// * This file is part of the COLOBOT source code
+// * Copyright (C) 2012, Polish Portal of Colobot (PPC)
+// *
+// * This program is free software: you can redistribute it and/or modify
+// * it under the terms of the GNU General Public License as published by
+// * the Free Software Foundation, either version 3 of the License, or
+// * (at your option) any later version.
+// *
+// * This program is distributed in the hope that it will be useful,
+// * but WITHOUT ANY WARRANTY; without even the implied warranty of
+// * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// * GNU General Public License for more details.
+// *
+// * You should have received a copy of the GNU General Public License
+// * along with this program. If not, see  http://www.gnu.org/licenses/.
+
+// image.h
+
+#pragma once
+
+
+#include <stddef.h>
+#include <string>
+
+
+// Forward declaration without including headers to clutter the code
+struct SDL_Surface;
+
+//! Implementation-specific image data
+/** Note that the struct has no destructor and the surface
+    will not be freed at destruction. */
+struct ImageData
+{
+    //! SDL surface with image data
+    SDL_Surface* surface;
+
+    ImageData() { surface = NULL; }
+};
+
+/**
+  \class CImage
+  \brief Image loaded from file
+
+  Wrapper around SDL_Image library to load images. Also contains
+  function for saving images to PNG.
+  */
+class CImage
+{
+private:
+    //! Blocked!
+    CImage(const CImage &other) {}
+    //! Blocked!
+    void operator=(const CImage &other) {}
+
+public:
+    //! Constructs empty image (with NULL data)
+    CImage();
+    //! Destroys image, calling Free()
+    virtual ~CImage();
+
+    //! Frees the allocated image data
+    void Free();
+
+    //! Returns whether the image is empty (has NULL data)
+    bool IsEmpty();
+
+    //! Returns the image data; if empty - returns NULL
+    ImageData* GetData();
+
+    //! Loads an image from the specified file
+    bool Load(const std::string &fileName);
+
+    //! Saves the image to the specified file in PNG format
+    bool SavePNG(const std::string &fileName);
+
+    //! Returns the last error
+    std::string GetError();
+
+private:
+    //! Last encountered error
+    std::string m_error;
+    //! Image data
+    ImageData* m_data;
+};
diff --git a/src/common/test/CMakeLists.txt b/src/common/test/CMakeLists.txt
new file mode 100644
index 0000000..680116c
--- /dev/null
+++ b/src/common/test/CMakeLists.txt
@@ -0,0 +1,6 @@
+cmake_minimum_required(VERSION 2.8)
+
+set(CMAKE_BUILD_TYPE debug)
+set(CMAKE_CXX_FLAGS_DEBUG "-Wall -g -O0")
+
+add_executable(image_test ../image.cpp image_test.cpp)
diff --git a/src/common/test/image_test.cpp b/src/common/test/image_test.cpp
new file mode 100644
index 0000000..0ad1ee2
--- /dev/null
+++ b/src/common/test/image_test.cpp
@@ -0,0 +1,34 @@
+#include "../image.h"
+
+#include <SDL/SDL.h>
+#include <stdio.h>
+
+/* For now, just a simple test: loading a file from image
+ * and saving it to another in PNG. */
+
+int main(int argc, char *argv[])
+{
+    if (argc != 3)
+    {
+        printf("Usage: %s in_image out_image\n", argv[0]);
+        return 0;
+    }
+
+    CImage image;
+
+    if (! image.Load(argv[1]))
+    {
+        std::string err = image.GetError();
+        printf("Error loading '%s': %s\n", err.c_str());
+        return 1;
+    }
+
+    if (! image.SavePNG(argv[2]))
+    {
+        std::string err = image.GetError();
+        printf("Error saving PNG '%s': %s\n", err.c_str());
+        return 2;
+    }
+
+    return 0;
+}
diff --git a/src/graphics/common/device.cpp b/src/graphics/common/device.cpp
index fcd4318..bb51699 100644
--- a/src/graphics/common/device.cpp
+++ b/src/graphics/common/device.cpp
@@ -31,3 +31,20 @@ void Gfx::DeviceConfig::LoadDefault()
     doubleBuf = true;
     noFrame = false;
 }
+
+void Gfx::TextureParams::LoadDefault()
+{
+    minFilter = Gfx::TEX_MIN_FILTER_NEAREST;
+    magFilter = Gfx::TEX_MAG_FILTER_NEAREST;
+
+    wrapS = Gfx::TEX_WRAP_REPEAT;
+    wrapT = Gfx::TEX_WRAP_REPEAT;
+
+    colorOperation = Gfx::TEX_MIX_OPER_MODULATE;
+    colorArg1 = Gfx::TEX_MIX_ARG_CURRENT;
+    colorArg2 = Gfx::TEX_MIX_ARG_TEXTURE;
+
+    alphaOperation = Gfx::TEX_MIX_OPER_MODULATE;
+    alphaArg1 = Gfx::TEX_MIX_ARG_CURRENT;
+    alphaArg2 = Gfx::TEX_MIX_ARG_TEXTURE;
+}
diff --git a/src/graphics/common/device.h b/src/graphics/common/device.h
index 961fb6b..3382c9a 100644
--- a/src/graphics/common/device.h
+++ b/src/graphics/common/device.h
@@ -30,6 +30,9 @@
 #include <string>
 
 
+class CImage;
+
+
 namespace Gfx {
 
 /**
@@ -145,6 +148,15 @@ enum CullMode
 };
 
 /**
+  \enum ShadeModel
+  \brief Shade model used in rendering */
+enum ShadeModel
+{
+    SHADE_FLAT,
+    SHADE_SMOOTH
+};
+
+/**
   \enum FillMode
   \brief Polygon fill mode */
 enum FillMode
@@ -170,6 +182,147 @@ enum PrimitiveType
 };
 
 /**
+  \enum TexMinFilter
+  \brief Minification texture filter
+
+  Corresponds to OpenGL modes but should translate to DirectX too. */
+enum TexMinFilter
+{
+    TEX_MIN_FILTER_NEAREST,
+    TEX_MIN_FILTER_LINEAR,
+    TEX_MIN_FILTER_NEAREST_MIPMAP_NEAREST,
+    TEX_MIN_FILTER_LINEAR_MIPMAP_NEAREST,
+    TEX_MIN_FILTER_NEAREST_MIPMAP_LINEAR,
+    TEX_MIN_FILTER_LINEAR_MIPMAP_LINEAR
+};
+
+/**
+  \enum TexMagFilter
+  \brief Magnification texture filter */
+enum TexMagFilter
+{
+    TEX_MAG_FILTER_NEAREST,
+    TEX_MAG_FILTER_LINEAR
+};
+
+/**
+  \enum TexWrapMode
+  \brief Wrapping mode for texture coords */
+enum TexWrapMode
+{
+    TEX_WRAP_CLAMP,
+    TEX_WRAP_REPEAT
+};
+
+/**
+  \enum TexMixOperation
+  \brief Multitexture mixing operation
+ */
+enum TexMixOperation
+{
+    TEX_MIX_OPER_MODULATE,
+    TEX_MIX_OPER_ADD
+};
+
+/**
+  \enum TexMixArgument
+  \brief Multitexture mixing argument
+  */
+enum TexMixArgument
+{
+    TEX_MIX_ARG_CURRENT,
+    TEX_MIX_ARG_TEXTURE,
+    TEX_MIX_ARG_DIFFUSE,
+    TEX_MIX_ARG_FACTOR
+};
+
+/**
+  \enum TextureParams
+  \brief Parameters for texture creation
+ */
+struct TextureParams
+{
+    //! Minification filter
+    Gfx::TexMinFilter minFilter;
+    //! Magnification filter
+    Gfx::TexMagFilter magFilter;
+    //! Wrap S coord mode
+    Gfx::TexWrapMode wrapS;
+    //! Wrap T coord mode
+    Gfx::TexWrapMode wrapT;
+    //! Mixing operation done on color values
+    Gfx::TexMixOperation colorOperation;
+    //! 1st argument of color operations
+    Gfx::TexMixArgument colorArg1;
+    //! 2nd argument of color operations
+    Gfx::TexMixArgument colorArg2;
+    //! Mixing operation done on alpha values
+    Gfx::TexMixOperation alphaOperation;
+    //! 1st argument of alpha operations
+    Gfx::TexMixArgument alphaArg1;
+    //! 2nd argument of alpha operations
+    Gfx::TexMixArgument alphaArg2;
+
+    //! Constructor; calls LoadDefault()
+    TextureParams()
+        { LoadDefault(); }
+
+    //! Loads the default values
+    void LoadDefault();
+};
+
+/*
+
+Notes for rewriting DirectX code:
+
+>> SetRenderState() translates to many functions depending on param
+
+D3DRENDERSTATE_ALPHABLENDENABLE    -> SetRenderState() with RENDER_STATE_BLENDING
+D3DRENDERSTATE_ALPHAFUNC           -> SetAlphaTestFunc() func
+D3DRENDERSTATE_ALPHAREF            -> SetAlphaTestFunc() ref
+D3DRENDERSTATE_ALPHATESTENABLE     -> SetRenderState() with RENDER_STATE_ALPHA_TEST
+D3DRENDERSTATE_AMBIENT             -> SetGlobalAmbient()
+D3DRENDERSTATE_CULLMODE            -> SetCullMode()
+D3DRENDERSTATE_DESTBLEND           -> SetBlendFunc() dest blending func
+D3DRENDERSTATE_DITHERENABLE        -> SetRenderState() with RENDER_STATE_DITHERING
+D3DRENDERSTATE_FILLMODE            -> SetFillMode()
+D3DRENDERSTATE_FOGCOLOR            -> SetFogParams()
+D3DRENDERSTATE_FOGENABLE           -> SetRenderState() with RENDER_STATE_FOG
+D3DRENDERSTATE_FOGEND              -> SetFogParams()
+D3DRENDERSTATE_FOGSTART            -> SetFogParams()
+D3DRENDERSTATE_FOGVERTEXMODE       -> SetFogParams() fog model
+D3DRENDERSTATE_LIGHTING            -> SetRenderState() with RENDER_STATE_LIGHTING
+D3DRENDERSTATE_SHADEMODE           -> SetShadeModel()
+D3DRENDERSTATE_SPECULARENABLE      -> doesn't matter (always enabled)
+D3DRENDERSTATE_SRCBLEND            -> SetBlendFunc() src blending func
+D3DRENDERSTATE_TEXTUREFACTOR       -> SetTextureFactor()
+D3DRENDERSTATE_ZBIAS               -> SetDepthBias()
+D3DRENDERSTATE_ZENABLE             -> SetRenderState() with RENDER_STATE_DEPTH_TEST
+D3DRENDERSTATE_ZFUNC               -> SetDepthTestFunc()
+D3DRENDERSTATE_ZWRITEENABLE        -> SetRenderState() with RENDER_STATE_DEPTH_WRITE
+
+
+>> SetTextureStageState() translates to SetTextureParams()
+
+Params from enum in struct TextureParams
+  D3DTSS_ADDRESS       -> Gfx::TexWrapMode wrapS, wrapT
+  D3DTSS_ALPHAARG1     -> Gfx::TexMixArgument alphaArg1
+  D3DTSS_ALPHAARG2     -> Gfx::TexMixArgument alphaArg2
+  D3DTSS_ALPHAOP       -> Gfx::TexMixOperation alphaOperation
+  D3DTSS_COLORARG1     -> Gfx::TexMixArgument colorArg1
+  D3DTSS_COLORARG2     -> Gfx::TexMixArgument colorArg2
+  D3DTSS_COLOROP       -> Gfx::TexMixOperation colorOperation
+  D3DTSS_MAGFILTER     -> Gfx::TexMagFilter magFilter
+  D3DTSS_MINFILTER     -> Gfx::TexMinFilter minFilter
+  D3DTSS_TEXCOORDINDEX -> doesn't matter (texture coords are set explicitly by glMultiTexCoordARB*)
+
+Note that D3DTSS_ALPHAOP or D3DTSS_COLOROP set to D3DTOP_DISABLE must translate to disabling the whole texture stage.
+In DirectX, you shouldn't mix enabling one and disabling the other.
+Also, if previous stage is disabled in DirectX, the later ones are disabled, too. In OpenGL, that is not the case.
+
+*/
+
+/**
   \class CDevice
   \brief Abstract interface of graphics device
 
@@ -226,20 +379,33 @@ public:
     //! Returns the current enable state of light at given index
     virtual bool GetLightEnabled(int index) = 0;
 
-    // TODO:
-    // virtual Gfx::Texture* CreateTexture(CImage *image) = 0;
-    // virtual void DestroyTexture(Gfx::Texture *texture) = 0;
+    //! Creates a texture from image; the image can be safely removed after that
+    virtual Gfx::Texture* CreateTexture(CImage *image, bool alpha, bool mipMap) = 0;
+    //! Deletes a given texture, freeing it from video memory
+    virtual void DestroyTexture(Gfx::Texture *texture) = 0;
+    //! Deletes all textures created so far
+    virtual void DestroyAllTextures() = 0;
 
-    //! Returns the maximum number of multitexture units
+    //! Returns the maximum number of multitexture stages
     virtual int GetMaxTextureCount() = 0;
     //! Sets the (multi)texture at given index
     virtual void SetTexture(int index, Gfx::Texture *texture) = 0;
     //! Returns the (multi)texture at given index
     virtual Gfx::Texture* GetTexture(int index) = 0;
+    //! Enables/disables the given texture stage
+    virtual void SetTextureEnabled(int index, bool enabled) = 0;
+    //! Returns the current enable state of given texture stage
+    virtual bool GetTextureEnabled(int index) = 0;
 
-    // TODO:
-    // virtual void GetTextureStageState() = 0;
-    // virtual void SetTextureStageState() = 0;
+    //! Sets the current params of texture with given index
+    virtual void SetTextureParams(int index, const Gfx::TextureParams &params) = 0;
+    //! Returns the current params of texture with given index
+    virtual Gfx::TextureParams GetTextureParams(int index) = 0;
+
+    //! Sets the texture factor to the given color value
+    virtual void SetTextureFactor(Gfx::Color &color) = 0;
+    //! Returns the current texture factor
+    virtual Gfx::Color GetTextureFactor() = 0;
 
     //! Renders primitive composed of vertices with single texture
     virtual void DrawPrimitive(Gfx::PrimitiveType type, Gfx::Vertex *vertices, int vertexCount) = 0;
@@ -297,6 +463,11 @@ public:
     //! Returns the current cull mode
     virtual Gfx::CullMode GetCullMode() = 0;
 
+    //! Sets the shade model
+    virtual void SetShadeModel(Gfx::ShadeModel model) = 0;
+    //! Returns the current shade model
+    virtual Gfx::ShadeModel GetShadeModel() = 0;
+
     //! Sets the current fill mode
     virtual void SetFillMode(Gfx::FillMode mode) = 0;
     //! Returns the current fill mode
diff --git a/src/graphics/common/texture.h b/src/graphics/common/texture.h
index ab894db..55d5c70 100644
--- a/src/graphics/common/texture.h
+++ b/src/graphics/common/texture.h
@@ -20,9 +20,16 @@
 
 namespace Gfx {
 
+/** \struct Texture*/
 struct Texture
 {
-    // TODO
+    //! Whether the texture was loaded
+    bool valid;
+    //! Id of the texture in graphics engine
+    unsigned int id;
+
+    Texture()
+        { valid = false; id = 0; }
 };
 
 }; // namespace Gfx
diff --git a/src/graphics/opengl/gldevice.cpp b/src/graphics/opengl/gldevice.cpp
index d105a93..c6e91e1 100644
--- a/src/graphics/opengl/gldevice.cpp
+++ b/src/graphics/opengl/gldevice.cpp
@@ -16,6 +16,7 @@
 
 // gldevice.cpp
 
+#include "common/image.h"
 #include "graphics/opengl/gldevice.h"
 
 #include <GL/gl.h>
@@ -30,21 +31,13 @@ namespace Gfx {
 
 struct GLDevicePrivate
 {
-    void (APIENTRY* glMultiTexCoord1fARB)(GLenum target, GLfloat s);
     void (APIENTRY* glMultiTexCoord2fARB)(GLenum target, GLfloat s, GLfloat t);
-    void (APIENTRY* glMultiTexCoord3fARB)(GLenum target, GLfloat s, GLfloat t, GLfloat r);
-    void (APIENTRY* glMultiTexCoord4fARB)(GLenum target, GLfloat s, GLfloat t, GLfloat r, GLfloat q);
     void (APIENTRY* glActiveTextureARB)(GLenum texture);
-    void (APIENTRY* glClientActiveTextureARB)(GLenum texture);
 
     GLDevicePrivate()
     {
-        glMultiTexCoord1fARB = NULL;
         glMultiTexCoord2fARB = NULL;
-        glMultiTexCoord3fARB = NULL;
-        glMultiTexCoord4fARB = NULL;
         glActiveTextureARB   = NULL;
-        glClientActiveTextureARB = NULL;
     }
 };
 
@@ -71,6 +64,7 @@ Gfx::CGLDevice::CGLDevice()
 {
     m_private = new Gfx::GLDevicePrivate();
     m_wasInit = false;
+    m_texturing = false;
 }
 
 
@@ -92,18 +86,10 @@ std::string Gfx::CGLDevice::GetError()
 
 bool Gfx::CGLDevice::Create()
 {
-    m_wasInit = true;
-
-    // TODO: move to functions?
-    glShadeModel(GL_SMOOTH);
-    glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
-
-    glMatrixMode(GL_PROJECTION);
-    glLoadIdentity();
-
-    glMatrixMode(GL_MODELVIEW);
-    glLoadIdentity();
-
+    /* First check for extensions
+       These should be available in standard OpenGL 1.3
+       But every distribution is different
+       So we're loading them dynamically through SDL_GL_GetProcAddress() */
 
     std::string extensions = std::string( (char*) glGetString(GL_EXTENSIONS));
 
@@ -119,37 +105,58 @@ bool Gfx::CGLDevice::Create()
         return false;
     }
 
+    m_private->glMultiTexCoord2fARB = (PFNGLMULTITEXCOORD2FARBPROC) SDL_GL_GetProcAddress("glMultiTexCoord2fARB");
+    m_private->glActiveTextureARB   = (PFNGLACTIVETEXTUREARBPROC)   SDL_GL_GetProcAddress("glActiveTextureARB");
+
+    if ((m_private->glMultiTexCoord2fARB == NULL) || (m_private->glActiveTextureARB == NULL))
+    {
+        m_error = "Could not load extension functions, even though they seem supported";
+        return false;
+    }
+
+    m_wasInit = true;
+
+    // This is mostly done in all modern hardware by default
+    // DirectX doesn't even allow the option to turn off perspective correction anymore
+    // So turn it on permanently
+    glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
+
+    // Set just to be sure
+    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
+    glMatrixMode(GL_MODELVIEW);
+    glLoadIdentity();
+
+
+    m_lights        = std::vector<Gfx::Light>(GL_MAX_LIGHTS, Gfx::Light());
+    m_lightsEnabled = std::vector<bool>      (GL_MAX_LIGHTS, false);
+
     int maxTextures = 0;
     glGetIntegerv(GL_MAX_TEXTURE_UNITS_ARB, &maxTextures);
-    m_textures = std::vector<Gfx::Texture*>(maxTextures, NULL);
 
-    m_lights = std::vector<Gfx::Light>(GL_MAX_LIGHTS, Gfx::Light());
-    m_lightsEnabled = std::vector<bool>(GL_MAX_LIGHTS, false);
-
-    m_private->glMultiTexCoord1fARB = (PFNGLMULTITEXCOORD1FARBPROC) SDL_GL_GetProcAddress("glMultiTexCoord1fARB");
-    m_private->glMultiTexCoord2fARB = (PFNGLMULTITEXCOORD2FARBPROC) SDL_GL_GetProcAddress("glMultiTexCoord2fARB");
-    m_private->glMultiTexCoord3fARB = (PFNGLMULTITEXCOORD3FARBPROC) SDL_GL_GetProcAddress("glMultiTexCoord3fARB");
-    m_private->glMultiTexCoord4fARB = (PFNGLMULTITEXCOORD4FARBPROC) SDL_GL_GetProcAddress("glMultiTexCoord4fARB");
-    m_private->glActiveTextureARB   = (PFNGLACTIVETEXTUREARBPROC)   SDL_GL_GetProcAddress("glActiveTextureARB");
-    m_private->glClientActiveTextureARB = (PFNGLCLIENTACTIVETEXTUREARBPROC) SDL_GL_GetProcAddress("glClientActiveTextureARB");
+    m_textures         = std::vector<Gfx::Texture*>     (maxTextures, NULL);
+    m_texturesEnabled  = std::vector<bool>              (maxTextures, false);
+    m_texturesParams   = std::vector<Gfx::TextureParams>(maxTextures, Gfx::TextureParams());
 
     return true;
 }
 
 void Gfx::CGLDevice::Destroy()
 {
-    m_private->glMultiTexCoord1fARB = NULL;
     m_private->glMultiTexCoord2fARB = NULL;
-    m_private->glMultiTexCoord3fARB = NULL;
-    m_private->glMultiTexCoord4fARB = NULL;
     m_private->glActiveTextureARB   = NULL;
-    m_private->glClientActiveTextureARB = NULL;
 
     // Delete the remaining textures
-    std::set<Gfx::Texture*>::iterator it;
-    for (it = m_allTextures.begin(); it != m_allTextures.end(); ++it)
-        delete *it;
-    m_allTextures.clear();
+    // Should not be strictly necessary, but just in case
+    DestroyAllTextures();
+
+    m_lights.clear();
+    m_lightsEnabled.clear();
+
+    m_textures.clear();
+    m_texturesEnabled.clear();
+    m_texturesParams.clear();
 
     m_wasInit = false;
 }
@@ -177,7 +184,7 @@ void Gfx::CGLDevice::Clear()
 
 void Gfx::CGLDevice::SetTransform(Gfx::TransformType type, const Math::Matrix &matrix)
 {
-    if (type == Gfx::TRANSFORM_WORLD)
+    if      (type == Gfx::TRANSFORM_WORLD)
     {
         m_worldMat = matrix;
         m_modelviewMat = Math::MultiplyMatrices(m_worldMat, m_viewMat);
@@ -205,7 +212,7 @@ void Gfx::CGLDevice::SetTransform(Gfx::TransformType type, const Math::Matrix &m
 
 const Math::Matrix& Gfx::CGLDevice::GetTransform(Gfx::TransformType type)
 {
-    if (type == Gfx::TRANSFORM_WORLD)
+    if      (type == Gfx::TRANSFORM_WORLD)
         return m_worldMat;
     else if (type == Gfx::TRANSFORM_VIEW)
         return m_viewMat;
@@ -219,7 +226,7 @@ const Math::Matrix& Gfx::CGLDevice::GetTransform(Gfx::TransformType type)
 
 void Gfx::CGLDevice::MultiplyTransform(Gfx::TransformType type, const Math::Matrix &matrix)
 {
-    if (type == Gfx::TRANSFORM_WORLD)
+    if      (type == Gfx::TRANSFORM_WORLD)
     {
         m_worldMat = Math::MultiplyMatrices(m_worldMat, matrix);
         m_modelviewMat = Math::MultiplyMatrices(m_worldMat, m_viewMat);
@@ -306,7 +313,7 @@ const Gfx::Light& Gfx::CGLDevice::GetLight(int index)
 void Gfx::CGLDevice::SetLightEnabled(int index, bool enabled)
 {
     assert(index >= 0);
-    assert(index < (int)m_lightsEnabled.size());
+    assert(index < (int)m_lights.size());
 
     m_lightsEnabled[index] = enabled;
 
@@ -321,11 +328,102 @@ bool Gfx::CGLDevice::GetLightEnabled(int index)
     return m_lightsEnabled[index];
 }
 
+Gfx::Texture* Gfx::CGLDevice::CreateTexture(CImage *image, bool alpha, bool mipMap)
+{
+    Gfx::Texture *result = new Gfx::Texture();
+
+    // Texturing must be enabled, so enable 1st texture stage
+    m_private->glActiveTextureARB(GL_TEXTURE0_ARB);
+    glEnable(GL_TEXTURE_2D);
+
+    glGenTextures(1, &result->id);
+    glBindTexture(GL_TEXTURE_2D, result->id);
+
+    GLenum sourceFormat = 0;
+    if (alpha)
+        sourceFormat = GL_RGBA;
+    else
+        sourceFormat = GL_RGB;
+
+    ImageData *data = image->GetData();
+    if (data == NULL)
+        return NULL;
+
+    if (mipMap)
+    {
+        gluBuild2DMipmaps(GL_TEXTURE_2D, GL_RGBA, data->surface->w,
+                          data->surface->h, sourceFormat, GL_UNSIGNED_BYTE,
+                          data->surface->pixels);
+    }
+    else
+    {
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, data->surface->w, data->surface->h,
+                     0, sourceFormat, GL_UNSIGNED_BYTE, data->surface->pixels);
+    }
+
+    // Restore previous setup of 1st texture stage
+    RestoreTextureStage(0);
+
+    return result;
+}
+
+void Gfx::CGLDevice::DestroyTexture(Gfx::Texture *texture)
+{
+    std::set<Gfx::Texture*>::iterator it = m_allTextures.find(texture);
+    if (it != m_allTextures.end())
+        m_allTextures.erase(it);
+
+    glDeleteTextures(1, &texture->id);
+}
+
+void Gfx::CGLDevice::DestroyAllTextures()
+{
+    std::set<Gfx::Texture*> allCopy = m_allTextures;
+    std::set<Gfx::Texture*>::iterator it;
+    for (it = allCopy.begin(); it != allCopy.end(); ++it)
+    {
+        DestroyTexture(*it);
+        delete *it;
+    }
+}
+
 int Gfx::CGLDevice::GetMaxTextureCount()
 {
     return m_textures.size();
 }
 
+/**
+  If \a texture is \c NULL or invalid, unbinds the given texture.
+  If valid, binds the texture and enables the given texture stage.
+  The setting is remembered, even if texturing is disabled at the moment. */
+void Gfx::CGLDevice::SetTexture(int index, Gfx::Texture *texture)
+{
+    assert(index >= 0);
+    assert(index < (int)m_textures.size());
+
+    // Enable the given texture stage
+    m_private->glActiveTextureARB(GL_TEXTURE0_ARB + index);
+    glEnable(GL_TEXTURE_2D);
+
+    if ((texture == NULL) || (! texture->valid))
+    {
+        glBindTexture(GL_TEXTURE_2D, 0); // unbind texture
+        m_textures[index] = NULL;        // remember the changes
+    }
+    else
+    {
+        glBindTexture(GL_TEXTURE_2D, texture->id);        // bind the texture
+        m_textures[index] = texture;                      // remember the changes
+        SetTextureParams(index, m_texturesParams[index]); // texture params need to be re-set for the new texture
+    }
+
+    // Disable the stage if it is set so
+    if ( (! m_texturing) || (! m_texturesEnabled[index]) )
+        glDisable(GL_TEXTURE_2D);
+}
+
+/**
+  Returns the previously assigned texture or \c NULL if the given stage is not enabled. */
 Gfx::Texture* Gfx::CGLDevice::GetTexture(int index)
 {
     assert(index >= 0);
@@ -334,14 +432,224 @@ Gfx::Texture* Gfx::CGLDevice::GetTexture(int index)
     return m_textures[index];
 }
 
-void Gfx::CGLDevice::SetTexture(int index, Gfx::Texture *texture)
+void Gfx::CGLDevice::SetTextureEnabled(int index, bool enabled)
 {
     assert(index >= 0);
     assert(index < (int)m_textures.size());
 
-    m_textures[index] = texture;
+    m_texturesEnabled[index] = enabled;
 
-    // TODO
+    m_private->glActiveTextureARB(GL_TEXTURE0_ARB + index);
+    if (enabled)
+        glEnable(GL_TEXTURE_2D);
+    else
+        glDisable(GL_TEXTURE_2D);
+}
+
+bool Gfx::CGLDevice::GetTextureEnabled(int index)
+{
+    assert(index >= 0);
+    assert(index < (int)m_textures.size());
+
+    return m_texturesEnabled[index];
+}
+
+/**
+  Sets the texture parameters for the given texture stage.
+  If the given texture was not set (bound) yet, nothing happens.
+  The settings are remembered, even if texturing is disabled at the moment. */
+void Gfx::CGLDevice::SetTextureParams(int index, const Gfx::TextureParams &params)
+{
+    assert(index >= 0);
+    assert(index < (int)m_textures.size());
+
+    // Remember the settings
+    m_texturesParams[index] = params;
+
+    // Enable the given stage
+    m_private->glActiveTextureARB(GL_TEXTURE0_ARB + index);
+    glEnable(GL_TEXTURE_2D);
+
+    GLint minF = 0;
+    if      (params.minFilter == Gfx::TEX_MIN_FILTER_NEAREST)                minF = GL_NEAREST;
+    else if (params.minFilter == Gfx::TEX_MIN_FILTER_LINEAR)                 minF = GL_LINEAR;
+    else if (params.minFilter == Gfx::TEX_MIN_FILTER_NEAREST_MIPMAP_NEAREST) minF = GL_NEAREST_MIPMAP_NEAREST;
+    else if (params.minFilter == Gfx::TEX_MIN_FILTER_LINEAR_MIPMAP_NEAREST)  minF = GL_LINEAR_MIPMAP_NEAREST;
+    else if (params.minFilter == Gfx::TEX_MIN_FILTER_NEAREST_MIPMAP_LINEAR)  minF = GL_NEAREST_MIPMAP_LINEAR;
+    else if (params.minFilter == Gfx::TEX_MIN_FILTER_LINEAR_MIPMAP_LINEAR)   minF = GL_LINEAR_MIPMAP_LINEAR;
+    else  assert(false);
+
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, minF);
+
+    GLint magF = 0;
+    if      (params.magFilter == Gfx::TEX_MAG_FILTER_NEAREST) magF = GL_NEAREST;
+    else if (params.magFilter == Gfx::TEX_MAG_FILTER_LINEAR)  magF = GL_LINEAR;
+    else  assert(false);
+
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, magF);
+
+    if      (params.wrapS == Gfx::TEX_WRAP_CLAMP)
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
+    else if (params.wrapS == Gfx::TEX_WRAP_REPEAT)
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+    else  assert(false);
+
+    if      (params.wrapT == Gfx::TEX_WRAP_CLAMP)
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
+    else if (params.wrapT == Gfx::TEX_WRAP_REPEAT)
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+    else  assert(false);
+
+
+    // Selection of operation and arguments
+    glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE);
+
+    // Color operation
+    if      (params.colorOperation == Gfx::TEX_MIX_OPER_MODULATE)
+        glTexEnvi(GL_TEXTURE_2D, GL_COMBINE_RGB, GL_MODULATE);
+    else if (params.colorOperation == Gfx::TEX_MIX_OPER_ADD)
+        glTexEnvi(GL_TEXTURE_2D, GL_COMBINE_RGB, GL_ADD);
+    else  assert(false);
+
+    // Color arg1
+    if (params.colorArg1 == Gfx::TEX_MIX_ARG_CURRENT)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_RGB, GL_PREVIOUS); // that's right - stupid D3D enum values
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB, GL_SRC_COLOR);
+    }
+    else if (params.colorArg1 == Gfx::TEX_MIX_ARG_TEXTURE)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_RGB, GL_TEXTURE);
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB, GL_SRC_COLOR);
+    }
+    else if (params.colorArg1 == Gfx::TEX_MIX_ARG_DIFFUSE)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_RGB, GL_PRIMARY_COLOR); // here as well
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB, GL_SRC_COLOR);
+    }
+    else  assert(false);
+
+    // Color arg2
+    if (params.colorArg2 == Gfx::TEX_MIX_ARG_CURRENT)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_RGB, GL_PREVIOUS);
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_RGB, GL_SRC_COLOR);
+    }
+    else if (params.colorArg2 == Gfx::TEX_MIX_ARG_TEXTURE)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_RGB, GL_TEXTURE);
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_RGB, GL_SRC_COLOR);
+    }
+    else if (params.colorArg2 == Gfx::TEX_MIX_ARG_DIFFUSE)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_RGB, GL_PRIMARY_COLOR);
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_RGB, GL_SRC_COLOR);
+    }
+    else  assert(false);
+
+    // Alpha operation
+    if      (params.alphaOperation == Gfx::TEX_MIX_OPER_MODULATE)
+        glTexEnvi(GL_TEXTURE_2D, GL_COMBINE_ALPHA, GL_MODULATE);
+    else if (params.alphaOperation == Gfx::TEX_MIX_OPER_ADD)
+        glTexEnvi(GL_TEXTURE_2D, GL_COMBINE_ALPHA, GL_ADD);
+    else  assert(false);
+
+    // Alpha arg1
+    if (params.alphaArg1 == Gfx::TEX_MIX_ARG_CURRENT)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_ALPHA, GL_PREVIOUS);
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_ALPHA, GL_SRC_ALPHA);
+    }
+    else if (params.alphaArg1 == Gfx::TEX_MIX_ARG_TEXTURE)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_ALPHA, GL_TEXTURE);
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_ALPHA, GL_SRC_ALPHA);
+    }
+    else if (params.alphaArg1 == Gfx::TEX_MIX_ARG_DIFFUSE)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_ALPHA, GL_PRIMARY_COLOR);
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_ALPHA, GL_SRC_ALPHA);
+    }
+    else  assert(false);
+
+    // Alpha arg2
+    if (params.alphaArg2 == Gfx::TEX_MIX_ARG_CURRENT)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_ALPHA, GL_PREVIOUS);
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_ALPHA, GL_SRC_ALPHA);
+    }
+    else if (params.alphaArg2 == Gfx::TEX_MIX_ARG_TEXTURE)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_ALPHA, GL_TEXTURE);
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_ALPHA, GL_SRC_ALPHA);
+    }
+    else if (params.alphaArg2 == Gfx::TEX_MIX_ARG_DIFFUSE)
+    {
+        glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_ALPHA, GL_PRIMARY_COLOR);
+        glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_ALPHA, GL_SRC_ALPHA);
+    }
+    else  assert(false);
+
+    // Disable the stage if it is set so
+    if ( (! m_texturing) || (! m_texturesEnabled[index]) )
+        glDisable(GL_TEXTURE_2D);
+}
+
+Gfx::TextureParams Gfx::CGLDevice::GetTextureParams(int index)
+{
+    assert(index >= 0);
+    assert(index < (int)m_textures.size());
+
+    return m_texturesParams[index];
+}
+
+void Gfx::CGLDevice::SetTextureFactor(Gfx::Color &color)
+{
+    // Needs to be set for all texture stages
+    for (int index = 0; index < (int)m_textures.size(); ++index)
+    {
+        // Activate stage
+        m_private->glActiveTextureARB(GL_TEXTURE0_ARB + index);
+        glEnable(GL_TEXTURE_2D);
+
+        glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, color.Array());
+
+        // Disable the stage if it is set so
+        if ( (! m_texturing) || (! m_texturesEnabled[index]) )
+            glDisable(GL_TEXTURE_2D);
+    }
+}
+
+Gfx::Color Gfx::CGLDevice::GetTextureFactor()
+{
+    // Get from 1st stage (should be the same for all stages)
+    m_private->glActiveTextureARB(GL_TEXTURE0_ARB);
+    glEnable(GL_TEXTURE_2D);
+
+    GLfloat color[4] = { 0.0f };
+    glGetTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, color);
+
+    // Disable the 1st stage if it is set so
+    if ( (! m_texturing) || (! m_texturesEnabled[0]) )
+        glDisable(GL_TEXTURE_2D);
+
+    return Gfx::Color(color[0], color[1], color[2], color[3]);
+}
+
+void Gfx::CGLDevice::RestoreTextureStage(int index)
+{
+    // Ensure that we're working with the right stage
+    m_private->glActiveTextureARB(GL_TEXTURE0_ARB + index);
+    glEnable(GL_TEXTURE_2D);
+
+    if (m_textures[index] != NULL)
+        glBindTexture(GL_TEXTURE_2D, m_textures[index]->id); // bind to the previous texture
+    else
+        glBindTexture(GL_TEXTURE_2D, 0); // unbind
+
+    // Disable the stage if it is set so
+    if ( (! m_texturing) || (! m_texturesEnabled[index]) )
+        glDisable(GL_TEXTURE_2D);
 }
 
 void Gfx::CGLDevice::DrawPrimitive(Gfx::PrimitiveType type, Vertex *vertices, int vertexCount)
@@ -374,7 +682,7 @@ void Gfx::CGLDevice::DrawPrimitive(Gfx::PrimitiveType type, Gfx::VertexCol *vert
 
     for (int i = 0; i < vertexCount; ++i)
     {
-        // TODO: specular?
+        // TODO: specular through EXT_separate_specular_color?
         glColor4fv((GLfloat*)vertices[i].color.Array());
         glTexCoord2fv((GLfloat*)vertices[i].texCoord.Array());
         glVertex3fv((GLfloat*)vertices[i].coord.Array());
@@ -395,8 +703,8 @@ void Gfx::CGLDevice::DrawPrimitive(Gfx::PrimitiveType type, VertexTex2 *vertices
     for (int i = 0; i < vertexCount; ++i)
     {
         glNormal3fv((GLfloat*) vertices[i].normal.Array());
-        // TODO glMultiTexCoord2fARB(GL_TEXTURE0_ARB, vertices[i].texCoord.x, vertices[i].texCoord.y);
-        // TODO glMultiTexCoord2fARB(GL_TEXTURE1_ARB, vertices[i].texCoord2.x, vertices[i].texCoord2.y);
+        m_private->glMultiTexCoord2fARB(GL_TEXTURE0_ARB, vertices[i].texCoord.x, vertices[i].texCoord.y);
+        m_private->glMultiTexCoord2fARB(GL_TEXTURE1_ARB, vertices[i].texCoord2.x, vertices[i].texCoord2.y);
         glVertex3fv((GLfloat*) vertices[i].coord.Array());
     }
 
@@ -412,14 +720,26 @@ void Gfx::CGLDevice::SetRenderState(Gfx::RenderState state, bool enabled)
     }
     else if (state == RENDER_STATE_TEXTURING)
     {
+        m_texturing = enabled;
+
         if (enabled)
         {
-            glEnable(GL_TEXTURE_2D);
-            // TODO multitexture
+            // All enabled multitexture stages have to be enabled
+            for (int index = 0; index < (int)m_textures.size(); ++index)
+            {
+                m_private->glActiveTextureARB(GL_TEXTURE0_ARB + index);
+                if (m_texturesEnabled[index])
+                    glEnable(GL_TEXTURE_2D);
+            }
         }
         else
         {
-            glDisable(GL_TEXTURE_2D);
+            // All multitexture stages have to be disabled
+            for (int index = 0; index < (int)m_textures.size(); ++index)
+            {
+                m_private->glActiveTextureARB(GL_TEXTURE0_ARB + index);
+                glDisable(GL_TEXTURE_2D);
+            }
         }
         return;
     }
@@ -445,12 +765,14 @@ void Gfx::CGLDevice::SetRenderState(Gfx::RenderState state, bool enabled)
 
 bool Gfx::CGLDevice::GetRenderState(Gfx::RenderState state)
 {
+    if (state == RENDER_STATE_TEXTURING)
+        return m_texturing;
+
     GLenum flag = 0;
 
     switch (state)
     {
         case Gfx::RENDER_STATE_DEPTH_WRITE: flag = GL_DEPTH_WRITEMASK; break;
-        case Gfx::RENDER_STATE_TEXTURING:   flag = GL_TEXTURE_2D; break;
         case Gfx::RENDER_STATE_LIGHTING:    flag = GL_DEPTH_WRITEMASK; break;
         case Gfx::RENDER_STATE_BLENDING:    flag = GL_BLEND; break;
         case Gfx::RENDER_STATE_FOG:         flag = GL_FOG; break;
@@ -602,7 +924,7 @@ void Gfx::CGLDevice::SetClearColor(Gfx::Color color)
 
 Gfx::Color Gfx::CGLDevice::GetClearColor()
 {
-    float color[4] = { 0.0f };
+    GLfloat color[4] = { 0.0f };
     glGetFloatv(GL_COLOR_CLEAR_VALUE, color);
     return Gfx::Color(color[0], color[1], color[2], color[3]);
 }
@@ -614,7 +936,7 @@ void Gfx::CGLDevice::SetGlobalAmbient(Gfx::Color color)
 
 Gfx::Color Gfx::CGLDevice::GetGlobalAmbient()
 {
-    float color[4] = { 0.0f };
+    GLfloat color[4] = { 0.0f };
     glGetFloatv(GL_LIGHT_MODEL_AMBIENT, color);
     return Gfx::Color(color[0], color[1], color[2], color[3]);
 }
@@ -662,6 +984,23 @@ Gfx::CullMode Gfx::CGLDevice::GetCullMode()
     return Gfx::CULL_CW;
 }
 
+void Gfx::CGLDevice::SetShadeModel(Gfx::ShadeModel model)
+{
+    if      (model == Gfx::SHADE_FLAT)   glShadeModel(GL_FLAT);
+    else if (model == Gfx::SHADE_SMOOTH) glShadeModel(GL_SMOOTH);
+    else  assert(false);
+}
+
+Gfx::ShadeModel Gfx::CGLDevice::GetShadeModel()
+{
+    GLenum flag = 0;
+    glGetIntegerv(GL_SHADE_MODEL, (GLint*)&flag);
+    if      (flag == GL_FLAT)    return Gfx::SHADE_FLAT;
+    else if (flag == GL_SMOOTH)  return Gfx::SHADE_SMOOTH;
+    else  assert(false);
+    return Gfx::SHADE_FLAT;
+}
+
 void Gfx::CGLDevice::SetFillMode(Gfx::FillMode mode)
 {
     if      (mode == Gfx::FILL_POINT) glPolygonMode(GL_FRONT_AND_BACK, GL_POINT);
@@ -677,6 +1016,6 @@ Gfx::FillMode Gfx::CGLDevice::GetFillMode()
     if      (flag == GL_POINT) return Gfx::FILL_POINT;
     else if (flag == GL_LINE)  return Gfx::FILL_LINES;
     else if (flag == GL_FILL)  return Gfx::FILL_FILL;
-    else assert(false);
+    else  assert(false);
     return Gfx::FILL_POINT;
 }
diff --git a/src/graphics/opengl/gldevice.h b/src/graphics/opengl/gldevice.h
index 298eb56..aa5dd04 100644
--- a/src/graphics/opengl/gldevice.h
+++ b/src/graphics/opengl/gldevice.h
@@ -97,9 +97,21 @@ public:
     virtual void SetLightEnabled(int index, bool enabled);
     virtual bool GetLightEnabled(int index);
 
+    virtual Gfx::Texture* CreateTexture(CImage *image, bool alpha, bool mipMap);
+    virtual void DestroyTexture(Gfx::Texture *texture);
+    virtual void DestroyAllTextures();
+
     virtual int GetMaxTextureCount();
-        virtual void SetTexture(int index, Gfx::Texture *texture);
+    virtual void SetTexture(int index, Gfx::Texture *texture);
     virtual Gfx::Texture* GetTexture(int index);
+    virtual void SetTextureEnabled(int index, bool enabled);
+    virtual bool GetTextureEnabled(int index);
+
+    virtual void SetTextureParams(int index, const Gfx::TextureParams &params);
+    virtual Gfx::TextureParams GetTextureParams(int index);
+
+    virtual void SetTextureFactor(Gfx::Color &color);
+    virtual Gfx::Color GetTextureFactor();
 
     virtual void DrawPrimitive(Gfx::PrimitiveType type, Vertex *vertices, int vertexCount);
     virtual void DrawPrimitive(Gfx::PrimitiveType type, Gfx::VertexCol *vertices, int vertexCount);
@@ -133,6 +145,9 @@ public:
     virtual void SetCullMode(Gfx::CullMode mode);
     virtual Gfx::CullMode GetCullMode();
 
+    virtual void SetShadeModel(Gfx::ShadeModel model);
+    virtual Gfx::ShadeModel GetShadeModel();
+
     virtual void SetFillMode(Gfx::FillMode mode) ;
     virtual Gfx::FillMode GetFillMode();
 
@@ -143,6 +158,7 @@ private:
     bool m_wasInit;
     //! Last encountered error
     std::string m_error;
+
     //! Current world matrix
     Math::Matrix m_worldMat;
     //! Current view matrix
@@ -151,16 +167,29 @@ private:
     Math::Matrix m_modelviewMat;
     //! Current projection matrix
     Math::Matrix m_projectionMat;
+
     //! The current material
     Gfx::Material m_material;
+
     //! Current lights
     std::vector<Gfx::Light> m_lights;
     //! Current lights enable status
     std::vector<bool> m_lightsEnabled;
-    //! Current textures
+
+    //! Whether texturing is enabled in general
+    bool m_texturing;
+    //! Current textures; \c NULL value means unassigned
     std::vector<Gfx::Texture*> m_textures;
+    //! Current texture stages enable status
+    std::vector<bool> m_texturesEnabled;
+    //! Current texture params
+    std::vector<Gfx::TextureParams> m_texturesParams;
+
     //! Set of all created textures
     std::set<Gfx::Texture*> m_allTextures;
+
+    //! Restores the state of given texture stage to the previously saved settings
+    void RestoreTextureStage(int index);
 };
 
 }; // namespace Gfx