Draws a symmetrical snowflake in white asterisks on a green screen with a red border. A FOR loop reads nineteen rows from DATA, each a column position and a string of asterisks and spaces, and prints them one under another with PRINT AT, building a six-armed flake 19 characters across.
Entry for the Vintage Computing Christmas Challenge 2025.
Program Analysis
The program is twelve lines. Line 10 sets BORDER 2, PAPER 4 and INK 7; lines 30 to 60 read and print the rows; lines 70 to 120 hold the data. The rows are stored in full rather than generated, and the bottom half of the data repeats the top half in reverse order, since the shape is symmetrical top to bottom.
Notable Techniques
- Each
DATAitem pairs a starting column with a row string, so leading spaces don’t have to be stored and the strings stay short. RESTOREat line 20 resets theDATApointer, so the drawing can be repeated withGO TO 10as well asRUNwithout an “Out of DATA” error.
Potential Issues
- None seen. The program ends after drawing, leaving the flake on screen with the report at the bottom.
Image Gallery
Note: Type-in program listings on this website use ZMAKEBAS notation for graphics characters.