Commander X16

Raytracer in Basic with a sphere and its shadow, and a plane with a pattern.

Originally written for C64 with Simon's Basic and published 1986 in german magazine c't (issue 1, page 104).

According to the article it took 3 to 4 hours on a c64. It's much faster on a x16, but nevertheless use warp mode.

I changed the following compared to the original code:

• 
  I added alternative plane pattern formulas in the lines 110 to 220 (4 patterns; just [un]comment the according lines)
  


• 
  I added lines 1205, 1206 and 1615 to read the input from data statements instead of user input
  


• 
  I changed the graphic commands (screen, line, pset)
  


• 
  from line 2000 and on I added the data for the objects 
  
  
  
  • 
    line 2010: the sphere (x, y, z, radius) and the position of the lamp (x, y, z); same for all pictures
    
  
  
  • 
    followed by individual data per picture (5 pictures; just [un]comment the according lines for the others)
    
    
    
    • 
      coordinates of camera (x, y, z) and viewing vector (x, y, z); e.g. lines 2064 and 2065
      
    
    
    • 
      aperture angles (horizontal, vertical); aspect ratio already adapted to X16; e.g. line 2066
      
    
    
    
    
  
  
  • 
    line 2080: data for the view; same for all pictures; 
    
    
    
    • 
      coordinates of top right corner (x, y)
      
    
    
    • 
      coordinates of bottom left corner (x, y)
      
    
    
    • 
      view window size (width, height)
      
    
    
    
    
  
  
  
  

Press "S" for a quick sketch or "D" for the real stuff ...

On demand I could share more info from the article content.

Tested with R38

Enjoy!