text: /*
  -----------------------------------------------------------------------------
  This source file is part of OGRE
      (Object-oriented Graphics Rendering Engine)
  For the latest info, see http://www.ogre3d.org/
  
  Copyright (c) 2000-2014 Torus Knot Software Ltd
  
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
  
  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
  -----------------------------------------------------------------------------
  */
  #ifndef _Image_H__
  #define _Image_H__
  
  #include "OgrePrerequisites.h"
  #include "OgreCommon.h"
  #include "OgrePixelFormat.h"
  
  namespace Ogre {
      /** \addtogroup Core
      *  @{
      */
      /** \addtogroup Image
      *  @{
      */
  
      enum ImageFlags
      {
          IF_COMPRESSED = 0x00000001,
          IF_CUBEMAP    = 0x00000002,
          IF_3D_TEXTURE = 0x00000004
      };
      /** Class representing an image file.
          @remarks
              The Image class usually holds uncompressed image data and is the
              only object that can be loaded in a texture. Image  objects handle 
              image data decoding themselves by the means of locating the correct 
              Codec object for each data type.
          @par
              Typically, you would want to use an Image object to load a texture
              when extra processing needs to be done on an image before it is
              loaded or when you want to blit to an existing texture.
      */
      class _OgreExport Image : public ImageAlloc
      {
      public:
          /** Standard constructor.
          */
          Image();
          /** Copy-constructor - copies all the data from the target image.
          */
          Image( const Image &img );
  
          /** Standard destructor.
          */
          ~Image();
  
          /** Assignment operator - copies all the data from the target image.
          */
          Image & operator = ( const Image & img );
  
          /** Flips (mirrors) the image around the Y-axis. 
              @remarks
                  An example of an original and flipped image:
                  <pre>                
                  originalimg
                  00000000000
                  00000000000
                  00000000000
                  00000000000
                  00000000000
                  ------------> flip axis
                  00000000000
                  00000000000
                  00000000000
                  00000000000
                  00000000000
                  originalimg
                  </pre>
          */
          Image & flipAroundY();
  
          /** Flips (mirrors) the image around the X-axis.
              @remarks
                  An example of an original and flipped image:
                  <pre>
                          flip axis
                              |
                  originalimg|gmilanigiro
                  00000000000|00000000000
                  00000000000|00000000000
                  00000000000|00000000000
                  00000000000|00000000000
                  00000000000|00000000000
                  </pre>
          */                 
          Image & flipAroundX();
  
          /** Stores a pointer to raw data in memory. The pixel format has to be specified.
              @remarks
                  This method loads an image into memory held in the object. The 
                  pixel format will be either greyscale or RGB with an optional
                  Alpha component.
                  The type can be determined by calling getFormat().             
              @note
                  Whilst typically your image is likely to be a simple 2D image,
                  you can define complex images including cube maps, volume maps,
                  and images including custom mip levels. The layout of the 
                  internal memory should be:
                  <ul><li>face 0, mip 0 (top), width x height (x depth)</li>
                  <li>face 0, mip 1, width/2 x height/2 (x depth/2)</li>
                  <li>face 0, mip 2, width/4 x height/4 (x depth/4)</li>
                  <li>.. remaining mips for face 0 .. </li>
                  <li>face 1, mip 0 (top), width x height (x depth)</li
                  <li>.. and so on. </li>
                  </ul>
                  Of course, you will never have multiple faces (cube map) and
                  depth too.
              @param data
                  The data pointer
              @param width
                  Width of image
              @param height
                  Height of image
              @param depth
                  Image Depth (in 3d images, numbers of layers, otherwise 1)
              @param format
                  Pixel Format
              @param autoDelete
                  If memory associated with this buffer is to be destroyed
                  with the Image object. Note: it's important that if you set
                  this option to true, that you allocated the memory using OGRE_ALLOC_T
                  with a category of MEMCATEGORY_GENERAL to ensure the freeing of memory 
                  matches up.
              @param numFaces
                  The number of faces the image data has inside (6 for cubemaps, 1 otherwise)
              @param numMipMaps
                  The number of mipmaps the image data has inside
              @note
                   The memory associated with this buffer is NOT destroyed with the
                   Image object, unless autoDelete is set to true.
              @remarks 
                  The size of the buffer must be numFaces * PixelUtil::getMemorySize(width, height, depth, format)
           */
          Image& loadDynamicImage( uchar* data, uint32 width, uint32 height,
                              uint32 depth,
                               PixelFormat format, bool autoDelete = false, 
                               size_t numFaces = 1, uint32 numMipMaps = 0);
          
          /// @overload
          Image& loadDynamicImage(uchar* data, uint32 width, uint32 height, PixelFormat format)
          {
              return loadDynamicImage(data, width, height, 1, format);
          }
          /** Loads raw data from a stream. See the function
              loadDynamicImage for a description of the parameters.
              @remarks 
                  The size of the buffer must be numFaces * PixelUtil::getMemorySize(width, height, depth, format)
              @note
                  Whilst typically your image is likely to be a simple 2D image,
                  you can define complex images including cube maps
                  and images including custom mip levels. The layout of the 
                  internal memory should be:
                  <ul><li>face 0, mip 0 (top), width x height (x depth)</li>
                  <li>face 0, mip 1, width/2 x height/2 (x depth/2)</li>
                  <li>face 0, mip 2, width/4 x height/4 (x depth/4)</li>
                  <li>.. remaining mips for face 0 .. </li>
                  <li>face 1, mip 0 (top), width x height (x depth)</li
                  <li>.. and so on. </li>
                  </ul>
                  Of course, you will never have multiple faces (cube map) and
                  depth too.
          */
          Image & loadRawData( 
              const DataStreamPtr& stream,
              uint32 width, uint32 height, uint32 depth,
              PixelFormat format,
              size_t numFaces = 1, uint32 numMipMaps = 0);
          /// @overload
          Image& loadRawData(const DataStreamPtr& stream, uint32 width, uint32 height,
                             PixelFormat format)
          {
              return loadRawData(stream, width, height, 1, format);
          }
  
          /** Loads an image file.
              @remarks
                  This method loads an image into memory. Any format for which 
                  an associated ImageCodec is registered can be loaded. 
                  This can include complex formats like DDS with embedded custom 
                  mipmaps, cube faces and volume textures.
                  The type can be determined by calling getFormat().             
              @param
                  filename Name of an image file to load.
              @param
                  groupName Name of the resource group to search for the image
              @note
                  The memory associated with this buffer is destroyed with the
                  Image object.
          */
          Image & load( const String& filename, const String& groupName );
  
          /** Loads an image file from a stream.
              @remarks
                  This method works in the same way as the filename-based load 
                  method except it loads the image from a DataStream object. 
                  This DataStream is expected to contain the 
                  encoded data as it would be held in a file. 
                  Any format for which an associated ImageCodec is registered 
                  can be loaded. 
                  This can include complex formats like DDS with embedded custom 
                  mipmaps, cube faces and volume textures.
                  The type can be determined by calling getFormat().             
              @param
                  stream The source data.
              @param
                  type The type of the image. Used to decide what decompression
                  codec to use. Can be left blank if the stream data includes
                  a header to identify the data.
              @see
                  Image::load( const String& filename )
          */
          Image & load(const DataStreamPtr& stream, const String& type = BLANKSTRING );
  
          /** Utility method to combine 2 separate images into this one, with the first
          image source supplying the RGB channels, and the second image supplying the 
          alpha channel (as luminance or separate alpha). 
          @param rgbFilename Filename of image supplying the RGB channels (any alpha is ignored)
          @param alphaFilename Filename of image supplying the alpha channel. If a luminance image the
              single channel is used directly, if an RGB image then the values are
              converted to greyscale.
          @param groupName The resource group from which to load the images
          @param format The destination format
          */
          Image & loadTwoImagesAsRGBA(const String& rgbFilename, const String& alphaFilename,
              const String& groupName, PixelFormat format = PF_BYTE_RGBA);
  
          /** Utility method to combine 2 separate images into this one, with the first
          image source supplying the RGB channels, and the second image supplying the 
          alpha channel (as luminance or separate alpha). 
          @param rgbStream Stream of image supplying the RGB channels (any alpha is ignored)
          @param alphaStream Stream of image supplying the alpha channel. If a luminance image the
              single channel is used directly, if an RGB image then the values are
              converted to greyscale.
          @param format The destination format
          @param rgbType The type of the RGB image. Used to decide what decompression
              codec to use. Can be left blank if the stream data includes
              a header to identify the data.
          @param alphaType The type of the alpha image. Used to decide what decompression
              codec to use. Can be left blank if the stream data includes
              a header to identify the data.
          */
          Image& loadTwoImagesAsRGBA(const DataStreamPtr& rgbStream, const DataStreamPtr& alphaStream,
                                     PixelFormat format = PF_BYTE_RGBA,
                                     const String& rgbType = BLANKSTRING,
                                     const String& alphaType = BLANKSTRING);
  
          /** Utility method to combine 2 separate images into this one, with the first
              image source supplying the RGB channels, and the second image supplying the 
              alpha channel (as luminance or separate alpha). 
          @param rgb Image supplying the RGB channels (any alpha is ignored)
          @param alpha Image supplying the alpha channel. If a luminance image the
              single channel is used directly, if an RGB image then the values are
              converted to greyscale.
          @param format The destination format
          */
          Image & combineTwoImagesAsRGBA(const Image& rgb, const Image& alpha, PixelFormat format = PF_BYTE_RGBA);
  
          
          /** Save the image as a file. 
          @remarks
              Saving and loading are implemented by back end (sometimes third 
              party) codecs.  Implemented saving functionality is more limited
              than loading in some cases. Particularly DDS file format support 
              is currently limited to true colour or single channel float32, 
              square, power of two textures with no mipmaps.  Volumetric support
              is currently limited to DDS files.
          */
          void save(const String& filename);
  
          /** Encode the image and return a stream to the data. 
              @param formatextension An extension to identify the image format
                  to encode into, e.g. "jpg" or "png"
          */
          DataStreamPtr encode(const String& formatextension);
  
          /** Returns a pointer to the internal image buffer.
          @remarks
              Be careful with this method. You will almost certainly
              prefer to use getPixelBox, especially with complex images
              which include many faces or custom mipmaps.
          */
          uchar* getData(void);
  
          /** Returns a const pointer to the internal image buffer.
          @remarks
              Be careful with this method. You will almost certainly
              prefer to use getPixelBox, especially with complex images
              which include many faces or custom mipmaps.
          */
          const uchar * getData() const;       
  
          /** Returns the size of the data buffer.
          */
          size_t getSize() const;
  
          /** Returns the number of mipmaps contained in the image.
          */
          uint32 getNumMipmaps() const;
  
          /** Returns true if the image has the appropriate flag set.
          */
          bool hasFlag(const ImageFlags imgFlag) const;
  
          /** Gets the width of the image in pixels.
          */
          uint32 getWidth(void) const;
  
          /** Gets the height of the image in pixels.
          */
          uint32 getHeight(void) const;
  
          /** Gets the depth of the image.
          */
          uint32 getDepth(void) const;
          
          /** Get the number of faces of the image. This is usually 6 for a cubemap, and
              1 for a normal image.
          */
          size_t getNumFaces(void) const;
  
          /** Gets the physical width in bytes of each row of pixels.
          */
          size_t getRowSpan(void) const;
  
          /** Returns the image format.
          */
          PixelFormat getFormat() const;
  
          /** Returns the number of bits per pixel.
          */
          uchar getBPP() const;
  
          /** Returns true if the image has an alpha component.
          */
          bool getHasAlpha() const;
          
          /** Does gamma adjustment.
              @note
                  Basic algo taken from Titan Engine, copyright (c) 2000 Ignacio 
                  Castano Iguado
          */
          static void applyGamma( uchar *buffer, Real gamma, size_t size, uchar bpp );
  
          /**
           * Get colour value from a certain location in the image. The z coordinate
           * is only valid for cubemaps and volume textures. This uses the first (largest)
           * mipmap.
           */
          ColourValue getColourAt(size_t x, size_t y, size_t z) const;
          
          /**
           * Set colour value at a certain location in the image. The z coordinate
           * is only valid for cubemaps and volume textures. This uses the first (largest)
           * mipmap.
           */
          void setColourAt(ColourValue const &cv, size_t x, size_t y, size_t z);
  
          /**
           * Get a PixelBox encapsulating the image data of a mipmap
           */
          PixelBox getPixelBox(size_t face = 0, size_t mipmap = 0) const;
  
          /// Delete all the memory held by this image, if owned by this image (not dynamic)
          void freeMemory();
  
          enum Filter
          {
              FILTER_NEAREST,
              FILTER_LINEAR,
              FILTER_BILINEAR,
              FILTER_BOX,
              FILTER_TRIANGLE,
              FILTER_BICUBIC
          };
          /** Scale a 1D, 2D or 3D image volume. 
              @param  src         PixelBox containing the source pointer, dimensions and format
              @param  dst         PixelBox containing the destination pointer, dimensions and format
              @param  filter      Which filter to use
              @remarks    This function can do pixel format conversion in the process.
              @note   dst and src can point to the same PixelBox object without any problem
          */
          static void scale(const PixelBox &src, const PixelBox &dst, Filter filter = FILTER_BILINEAR);
          
          /** Resize a 2D image, applying the appropriate filter. */
          void resize(ushort width, ushort height, Filter filter = FILTER_BILINEAR);
          
          /// Static function to calculate size in bytes from the number of mipmaps, faces and the dimensions
          static size_t calculateSize(size_t mipmaps, size_t faces, uint32 width, uint32 height, uint32 depth, PixelFormat format);
  
          /// Static function to get an image type string from a stream via magic numbers
          static String getFileExtFromMagic(DataStreamPtr stream);
  
      protected:
          /// The width of the image in pixels
          uint32 mWidth;
          /// The height of the image in pixels
          uint32 mHeight;
          /// The depth of the image
          uint32 mDepth;
          /// The size of the image buffer
          size_t mBufSize;
          /// The number of mipmaps the image contains
          uint32 mNumMipmaps;
          /// Image specific flags.
          int mFlags;
  
          /// The pixel format of the image
          PixelFormat mFormat;
  
          /// The number of bytes per pixel
          uchar mPixelSize;
          uchar* mBuffer;
  
          /// A bool to determine if we delete the buffer or the calling app does
          bool mAutoDelete;
      };
  
      typedef vector<Image*>::type ImagePtrList;
      typedef vector<const Image*>::type ConstImagePtrList;
  
      /** @} */
      /** @} */
  
  } // namespace
  
  #endif
  