graph.h

Ftee type Demo for Linux open source

/***************************************************************************
 *
 *  graph.h
 *
 *    Graphics Subsystem interface
 *
 *  Copyright 1999, 2000, 2001, 2002
 *     - The FreeType Development Team - www.freetype.org
 *
 ***************************************************************************/

#ifndef GRAPH_H
#define GRAPH_H

#include "grevents.h"

 /*************************************************************************/
 /*************************************************************************/
 /*************************************************************************/
 /********                                                         ********/
 /********         GENERAL DEFINITIONS AND BLITTING ROUTINES       ********/
 /********                                                         ********/
 /********                                                         ********/
 /*************************************************************************/
 /*************************************************************************/
 /*************************************************************************/


  /* define the global error variable */
  extern int  grError;

  /* initialisation */
  extern int  grInit( void );

  /* finalisation */
  extern void grDone( void );


  /* pixel mode constants */
  typedef enum grPixelMode
  {
    gr_pixel_mode_none = 0,
    gr_pixel_mode_mono,        /* monochrome bitmaps               */
    gr_pixel_mode_pal4,        /* 4-bit paletted - 16 colors       */
    gr_pixel_mode_pal8,        /* 8-bit paletted - 256 colors      */
    gr_pixel_mode_gray,        /* 8-bit gray levels                */
    gr_pixel_mode_rgb555,      /* 15-bits mode - 32768 colors      */
    gr_pixel_mode_rgb565,      /* 16-bits mode - 65536 colors      */
    gr_pixel_mode_rgb24,       /* 24-bits mode - 16 million colors */
    gr_pixel_mode_rgb32,       /* 32-bits mode - 16 million colors */
    gr_pixel_mode_lcd,         /* horizontal RGB-decimated         */
    gr_pixel_mode_lcdv,        /* vertical RGB-decimated           */
    gr_pixel_mode_lcd2,        /* horizontal BGR-decimated         */
    gr_pixel_mode_lcdv2,       /* vertical BGR-decimated           */

    gr_pixel_mode_max          /* don't remove */

  } grPixelMode;


  /* forward declaration of the surface class */
  typedef struct grSurface_     grSurface;


 /*********************************************************************
  *
  * <Struct>
  *   grBitmap
  *
  * <Description>
  *   a simple bitmap descriptor
  *
  * <Fields>
  *   rows   :: height in pixels
  *   width  :: width in pixels
  *   pitch  :: + or - the number of bytes per row
  *   mode   :: pixel mode of bitmap buffer
  *   grays  :: number of grays in palette for PAL8 mode. 0 otherwise
  *   buffer :: pointer to pixel buffer
  *
  * <Note>
  *   the 'pitch' is positive for downward flows, and negative otherwise
  *   Its absolute value is always the number of bytes taken by each
  *   bitmap row.
  *
  *   All drawing operations will be performed within the first
  *   "width" pixels of each row (clipping is always performed).
  *
  ********************************************************************/

  typedef struct grBitmap_
  {
    int             rows;
    int             width;
    int             pitch;
    grPixelMode     mode;
    int             grays;
    unsigned char*  buffer;

  } grBitmap;



  typedef long   grPos;
  typedef char   grBool;

  typedef struct grVector_
  {
    grPos  x;
    grPos  y;

  } grVector;


  typedef union grColor_
  {
    long           value;
    unsigned char  chroma[4];

  } grColor;



 /**********************************************************************
  *
  * <Function>
  *    grNewBitmap
  *
  * <Description>
  *    creates a new bitmap
  *
  * <Input>
  *    pixel_mode   :: the target surface's pixel_mode
  *    num_grays    :: number of grays levels for PAL8 pixel mode
  *    width        :: width in pixels
  *    height       :: height in pixels
  *
  * <Output>
  *    bit          :: descriptor of the new bitmap
  *
  * <Return>
  *    Error code. 0 means success.
  *
  * <Note>
  *    This function really allocates a pixel buffer, zero it, then
  *    returns a descriptor for it.
  *
  *    Call grDoneBitmap when you're done with it..
  *
  **********************************************************************/

  extern  int  grNewBitmap( grPixelMode  pixel_mode,
                            int          num_grays,
                            int          width,
                            int          height,
                            grBitmap    *bit );


 /**********************************************************************
  *
  * <Function>
  *    grBlitGlyphToBitmap
  *
  * <Description>
  *    writes a given glyph bitmap to a target surface.
  *
  * <Input>
  *    target  :: handle to target bitmap
  *    glyph   :: handle to source glyph bitmap
  *    x       :: position of left-most pixel of glyph image in target surface
  *    y       :: position of top-most pixel of glyph image in target surface
  *    color   :: color to be used to draw a monochrome glyph
  *
  * <Return>
  *   Error code. 0 means success
  *
  * <Note>
  *   There are only two supported source pixel modes : monochrome
  *   and gray. The 8-bit images can have any number of grays between
  *   2 and 128, and conversions to the target surface is handled
  *   _automatically_.
  *
  *   Note however that you should avoid blitting a gray glyph to a gray
  *   bitmap with fewer levels of grays, as this would much probably
  *   give unpleasant results..
  *
  *   This function performs clipping
  *
  **********************************************************************/

  extern int
  grBlitGlyphToBitmap( grBitmap*  target,
                       grBitmap*  glyph,
                       grPos      x,
                       grPos      y,
                       grColor    color );


 /**********************************************************************
  *
  * <Function>
  *    grFillRectangle
  *
  * <Description>
  *    this function is used to fill a given rectangle on a surface
  *
  * <Input>
  *    surface :: handle to target surface
  *    x       :: x coordinate of the top-left corner of the rectangle
  *    y       :: y coordinate of the top-left corner of the rectangle
  *    width   :: rectangle width in pixels
  *    height  :: rectangle height in pixels
  *    color   :: fill color
  *
  **********************************************************************/

  extern void  grFillRectangle( grBitmap*  surface,
                                grPos      x,
                                grPos      y,
                                grPos      width,
                                grPos      height,
                                grColor    color );



 /**********************************************************************
  *
  * <Function>
  *    grWriteCellChar
  *
  * <Description>
  *    The graphics sub-system contains an internal Latin1 8x8 font
  *    which can be used to display simple strings of text without
  *    using FreeType.
  *
  *    This function writes a single 8x8 character on the target bitmap.
  *
  * <Input>
  *    target   :: handle to target surface
  *    x        :: x pixel position of character cell's top left corner
  *    y        :: y pixel position of character cell's top left corner
  *    charcode :: Latin-1 character code
  *    color    :: color to be used to draw the character
  *
  **********************************************************************/

  extern
  void  grWriteCellChar( grBitmap*  target,
                         int        x,
                         int        y,
                         int        charcode,
                         grColor    color );


 /**********************************************************************
  *
  * <Function>
  *    grWriteCellString
  *
  * <Description>
  *    The graphics sub-system contains an internal Latin1 8x8 font
  *    which can be used to display simple strings of text without
  *    using FreeType.
  *
  *    This function writes a string with the internal font
  *
  * <Input>
  *    target       :: handle to target bitmap
  *    x            :: x pixel position of string's top left corner
  *    y            :: y pixel position of string's top left corner
  *    string       :: Latin-1 text string
  *    color        :: color to be used to draw the character
  *
  **********************************************************************/

  extern
  void  grWriteCellString( grBitmap*   target,
                           int         x,
                           int         y,
                           const char* string,
                           grColor     color );

 /**********************************************************************
  *
  * <Function>
  *    grDoneBitmap
  *
  * <Description>
  *    destroys a bitmap
  *
  * <Input>
  *    bitmap :: handle to bitmap descriptor
  *
  * <Note>
  *    This function does NOT release the bitmap descriptor, only
  *    the pixel buffer.
  *
  **********************************************************************/

  extern  void  grDoneBitmap( grBitmap*  bit );




 /*************************************************************************/
 /*************************************************************************/
 /*************************************************************************/
 /********                                                         ********/
 /********         DEVICE-SPECIFIC DEFINITIONS AND ROUTINES        ********/
 /********                                                         ********/
 /********                                                         ********/
 /*************************************************************************/
 /*************************************************************************/
 /*************************************************************************/


  /* forward declaration - the definition of grDevice is not visible */
  /* to clients..                                                    */
  typedef struct grDevice_  grDevice;


 /**********************************************************************
  *
  * <Struct>
  *    grDeviceChain
  *
  * <Description>