Allegro is a game programming library for C/C++ developers distributed freely, supporting the following platforms: DOS, Unix (Linux, FreeBSD, Irix, Solaris, Darwin), Windows, QNX, BeOS and MacOS X. It provides many functions for graphics, sounds, player input (keyboard, mouse and joystick) and timers. It also provides fixed and floating point mathematical functions, 3d functions, file management functions, compressed datafile and a GUI.

Graphic functions

• Vector drawing:
  
  • pixels, lines, rectangles, circles, ellipses, arcs, Bezier splines
    
  • shape fill, with or without pattern
    
  • polygons: flat, Gouraud, textured (3D) and translucent
    
  
  
• Sprites:
  
  • masked, compressed and compiled sprites
    
  • blitting, rotation, stretching, reduction, alpha blending, Gouraud shading
    
  • native support for BMP, LBM, PCX and TGA files (others supported with library extensions)
    
  
  
• Color palettes:
  
  • color palette manipulation (reading, writing, conversion)
    
  • conversion of color formats RGB <-> HSV
    
  
  
• Text:
  
  • support for different encodings and conversion, default is UTF-8
    
  • bitmap fonts (masking, colouring, alignment)
    
  
  
• Misc:
  
  • draw directly on the screen or on any-size memory bitmaps
    
  • hardware scrolling and triple buffering (where available), mode-X split screen
    
  • animation functions for FLI/FLC format