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

1 files changed, 84 insertions, 0 deletions

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;
+};