Abk Viewer Beta 1.4 - Java AMOS Sprite Bank Viewer
Abk Viewer is a simple Java-based viewer for Commodore Amiga AMOS BASIC Sprite and Icon banks.
Some sample .abk files are included and downloadable from the 'abk' directory (under 'Files').
Changes from initial release beta 1.0:
- Now uses an OS-native file selector - should be especially easier to use on Mac OS X.
- Should work fine now with non-local file access - can load files from any available path.
- Uses a faster loading algorithm.
- Now has full command line support:
"java -jar AbkViewer.jar" loads a file selector to choose the .abk file,
"java -jar AbkViewer.jar Sprites.Abk" loads a specified .abk file (from any available path).
Changes from beta 1.1:
- Now uses a much faster sprite rendering algorithm.
Changes from beta 1.2:
- Now more object-oriented and uses multiple Java classes. The source is easier to follow as a result.
A buildable Eclipse archive is included, as well as the Java source files for browsing.
Changes from beta 1.3:
- Now supports 64 colour Extra Half-Brite (EHB) images.
- Now supports banks with empty images.
- Should now support all AMOS BASIC sprite banks.
ABK file format information:
AMOS Sprite banks (.abk) are also known as Object banks (in AMOS Professional) or Bob banks (in Easy AMOS).
These are a collection of bit-mapped paletted images with up to 32 colours from a palette of 4096 (0xFFF, 12 bits).
Note that there are also other types of AMOS bank which are also saved with '.abk' extension, but are not covered here.
Each image includes a "hot spot" or handle with both a horizontal and vertical offset.
Each image has a variable amount of bit-planes - from 1 bit-plane giving 2 colours, to 5 bit-planes giving 32.
An Extra Half-Brite mode is also supported with 64 colours on 6 bit-planes. This works by doubling a 32 colour palette and halving the brightness of the last 32 indexes.
One palette of 32 defined colours (from a palette of 4096) is included in each .abk bank.
The first colour entry (0) can be treated as transparent for sprites.
AMOS Icon banks are identical to Sprite banks, only the file begins with "AmIc" instead of "AmSp".
For more on this ABK format, see heading: "Object banks and Icon banks stored on disc":