Atari Game Tools

This is a small collection of tools and code aimed at rapid prototyping of Atari ST/E games.

Project Features

50hz 2D game engine, designed to help develop/test game ideas very quickly
full engine source + demos + examples + tutorials (all as source)
fast enough to outperform many old commercial releases
game level components can be in C/C++, low level components are 68k
tools for preparing & extracting art assets & palettes
works with various distributions of Atari GCC compiler tools
minimal external dependencies/prerequisites for setup - just a working shell & compiler!

Project Documentation: (in progress)

Engine Features:

Any type of scrolling - vertical, horizontal, 4- or 8-way, fixedpoint vector, direction & speed changes.
Work with 16x16 or 8x8 tilemaps, of any size
Single or dual-layer tilemaps (both layers editiable in TILED, with second, transparent layer masked on top of first)
Live-editable map layers ('mapmod' function) with optimised refresh of edited tiles for animation, doors or limited parallax
multiple sprite formats optimised for different scenarios (drawing speed vs. size vs. memory overhead vs. extraction time)
All sprite methods provide clipping & automatic background clearing/restore
Flexible Entity/AI system supports:
- spawn chaining (entities can spawn or kill entities)
- vistrigger mode (spawned into map at level load, dormant/no-overhead until entering viewport)
- plenty of example code for different kinds of behaviour
- object parent linkage & tracking
Object Interaction system provides mechanism for collisions, triggers
Input layer provides direct and debounced key & joystick state.
Comprehensive tools for converting, extracting assets including maps, tiles, sprites (& related), palettes
Edit maps in TILED editor and export to AGT in seconds
Collision tilemaps can be created and imported separately from the main visual tilemaps
Edit object/entity placements in TILED and export with map for direct parsing by game
Transparent support for compressed assets using 7 different packing modes, all CRC-wrapped
Built-in debugging features including:
- message console for errors, warnings & user info
- asserts to catch unexpected values etc.
- game object safety checks & diagnostics (bad animation frames etc.)
- debugdraw object rectangles
- built in profiler
- memory tracing
- Hatari and STEEM message logging
Top/bottom overscan & optional colour boosting via interlaced playfields
Dynamic screen splitting & palette changes via a copper-like 'Nickel' interface
Support for direct draw calls where needed

[in progress] - auto asset management

[pending] - text/fonts

Tutorials:

Gradual buildup from backgrounds through sprites to interactions & game content

Demos:

Gradius H-SHMUP: Horizontal scrolling shmup game with entities & interactions
Isometric scroller: entities in 3D space, drawing in ISO 2D
Alien Breed mockup: multiway scroll + solid wall interactions with 40 aliens
Boss Core: Huge boss sprite with complex behaviour & entity event linkage
PENDING: Xenon 1 L1 mockup with XML enemy placements & CVS collision layer imported from Tiled
PENDING: Gradius YM demo (music track selection, tracks prepared using agtym tool)

Examples:

8x8 scrolling 1-layer map with tile animation
8x8 scrolling 2-layer map with tile animation on both layers
16x16 scrolling 2-layer map with tile animation on both layers

Tools:

agtcut: asset processing/extraction tool
agtrip: background scroll ripping tool
agtym: YM music conversion tool
pcs: for superpalette generation

Credits:

Thanks to some people who contributed directly or otherwise:

ggn/kua for RMAC additions, fixes, support & testing all the things
Anima who provided the original idea for the EM sprite techniques used by AGT's EMSPR/EMXSPR formats.
XiA who provided XPRN font rendering & fonts for the new AGT console.
Antonio for testing, input/ideas & suggestions
Sqward, & Saulot whose code the Mini C++ CRT startup is based upon.
Matt Lacey for early feedback on pre-release source & testing a MacOS environment.
Eero Tamminen's Hatari Natfeats module for debugging support

Compression support:

Markus Franz Xaver Johannes Oberhumer's NRV2e decompression code & pack2e compressor
tAt/Avena for LZSA decompression routines
Mr Ni! for ARJ decompression routines
ray/tscc for LZ77 tools & code
Emmanuel Marty for LZSA compressor

Wiki

agtools / Home