|
|
Introduction
Allegro is a portable library mainly aimed at video game and multimedia programming,
originally started by Shawn Hargreaves
for the DJGPP compiler in a mixture of C and assembler.
According to the Oxford Companion to Music, Allegro is the Italian for
«quick, lively, bright». It is also a recursive acronym which stands for
«Allegro Low LEvel Game ROutines».
Cross-platform support
- Unix (Linux, FreeBSD, Irix, Solaris, Darwin)
- Windows (MSVC, MinGW, Cygwin, Borland)
- BeOS
- QNX
- MacOS X
- Dos (DJGPP, Watcom)
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
Graphic drivers
- Unix:
- X Window, DGA, fbcon
- SVGAlib
- VBE/AF
- mode-X
- VGA
- Windows:
- DirectX (windowed or full-screen)
- GDI
- MacOS X:
- Quartz (windowed or full-screen)
- BeOS:
- BWindowScreen
- BDirectWindow
- Dos:
- VGA 13h mode
- mode-X (23 VGA resolution plus unchained 640x400 extended mode)
- SVGA modes in 8, 15, 16, 24 and 32 bits per pixel
- linear VBE 2.0 framebuffer access
- hardware acceleration through VBE/AF API if supported
- additional graphic drivers through FreeBE/AF project
- OpenGL:
- The AllegroGL addon allows to
use OpenGL graphics with Allegro.
Sound functions
- Midi:
- native MIDI music format support (with 64 simultaneous effects)
- dynamic control/response to music note on, note off, main volume, pan, pitch bend, and program change
- uses General MIDI patches
- you can read in wavetable patches for MIDI files (SF2 and GUS patches)
- Wave:
- native support of WAV and VOC file formats (playing looped forward, backwards or bidirectional)
- streaming audio
- modify volume, pan, pitch, etc during play
Sound drivers
- Unix:
- OSS
- ALSA (0.5/0.9/1.0)
- ESD
- aRts
- JACK
- SGI AL
- Windows:
- DirectSound
- WaveOut
- MIDI system drivers
- MacOS X:
- Core Audio
- Sound Manager
- Core Audio MIDI
- QuickTime MIDI
- Dos:
- Adlib, SB, SB Pro, SB16, AWE32
- MPU-401
- ESS AudioDrive
- Ensoniq Soundscape
- Windows Sound System
Math functions
- fixed point arithmetic and trigonometric routines
- precalculated trigonometric tables
- vector/matrix/quaternions 3d manipulation (translation, rotation, scaling, projection)
Misc
- mouse, keyboard and joystick management
- high resolution interrupt timers (resolution of 10, 5 or less ms depending on platform)
- vertical retrace simulation
- manipulate configuration files
- manipulate compressed files in LZSS format
- manipulate multi-object resource-like compressed datafiles
- tool for creating datafiles (grabber)
- simple GUI for dialogs and file selector
I am new to Allegro, what should I do?
First of all, welcome! Depending on your skills you might want to
start with something different.
If you are a total beginner to C programming, Allegro won't help you
much. As a C library (C stands for the name of a programming
language), Allegro presumes you know how to write C programs,
compile and link them to produce executables. Sorry, you will have
to learn how to do that first. You can use a search engine like
Google to find tutorials and
documentation about C programming or buy a book in a shop on the
subject. C is a well known language with many years on its back,
so you won't have too many problems finding information about it.
If you already know how to write C programs but lack the knowledge for
writing games, you will enjoy learning and using Allegro. Obviously
you will want to download
Allegro. We recommend you to get the stable version. Allegro comes
with a good reference documentation and more than 40 examples which
will help you to start with basic things and from there on improve
your skills. You can even play a small demo game where your mission
is to blast asteroids. The documentation bundled with Allegro
can be found online,
and there are many tutorials
and even some books which
can be used to further enhance your knowledge.
If you are an experienced game programmer you can quickly get an
idea of how Allegro programs look like by skimming through the
API or reading the bundled examples. Allegro tries to make the task of
creating games as simple as possible to you, while maintaining the
flexibility to utilize all the low level power you may want to use at the
same time.
Whether you are a beginner or not, you should know that there are a
few ways to get in touch with other Allegro users. There are a few mailing lists you can subscribe
to. They are usually silent until somebody starts a nice discussion
and everybody jumps in with replies. For the mail impaired, Allegro.cc is a Web based forum
with a much higher participation (and also noise-to-signal ratio).
Feel free to communicate your ideas and current projects. Everybody
likes to see a game pushing Allegro to the limits, even more if
you provide the source code for others to learn from it.
|
