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<root>­/­parties­/­2022­/­vccc22­/­christmas_star_challenge/loki_c64_assembler_vc3-2022.zip

File size:
147 011 bytes (143.57K)
File date:
2022-12-30 11:32:13
Download count:
all-time: 10

Preview

  • file_id.diz 1.09K
  • result.png 1.92K
  • source.png 145.45K
  • xmasstar.asm 1.54K
  • xmasstar.prg 79B

file_id.diz

XMas Star

Author:   Michal Lokša [SinDiKat]
Category: Christmas Challenge
System:   C64
Language: Assembler
Compiled by: KickAssembler 1.3.5
Length of source code: 1573 Bytes
Length of exe file:    79 Bytes
Length of code only:   65 Bytes
Instructions:
   Run xmasstar.prg in any C64 emulator, e.g. Vice (x64sc.exe) by opening from menu
   or directly from command line (x64sc.exe xmasstar.prg)
Description:
   Program draws 5 stars from smaller to bigger. This is first loop.
   Each star is drawn by on one continous draw consisting of 8 lines. This is second loop.
   There are two different line lengths in each star.
   Line is drawn in third loop.
   Relative position of next "pixel" for current line is get from offset table lying at the end.
   Interresting things:
   - smaller stars have its offset done by Y register and choosing smaller line lengths.
     Therefore first pixel in absolute coordinates is always the same.
   - There are used default values from zero page to save code.
     Two zeroes and one value 8 which means largest line in smallest star.
Comments:
   -