Author: Anders Carlsson <anders.carlsson@sfks.se>
System: Commodore VIC-20
Language: BASIC V2 + ML routines
Source code ASCII: 1073 characters
Executable size: 898 bytes (excluding 2 byte load address)
Wild entry to the VCC24 contest, consisting of the package with custom
graphics, with the tree from 2021 and star from 2022 inside the package.
Three screenshots are submitted to illustrate the three stages.
How to run:
1. Start a VIC-20 emulator like xvic/VICE in unexpanded mode
2. Drop PRG file into the emulator
3. Program loads and autostarts
First the package is drawn, then copied to a second area in order to draw
the tree on top of it, and then draw the star on top of the first package.
There are two helper ML routines that simply copy segments of data, first
the character ROM to RAM and the other to copy screen from RAM to RAM.
It utilizes multi-colour characters, 4x8 chunky pixels where the auxillary
colour (high nybble of the volume register) is used. An early version also
utilized the border colour for the fourth multi-color, though not used here.