' cube rotator
 ' From a 19 liner by Entropy, shrinked by Antoni Gual
 ' for Rel's 9 LINER contest at QBASICNEWS.COM  1/2003
 ' translated to MMBasic for the CMM2 by TassyJim May 2020
 
 DIM INTEGER x,y,z
 DIM FLOAT r,x1,y1
 DIM FLOAT COSr,SINr,denom,xyz
 DIM INTEGER cx = MM.HRES/2  'scale things for different display resolution
 DIM INTEGER cy = MM.VRES/2
 DIM INTEGER b = cx/2
 DIM INTEGER s = cx*3/4
 CLS
 
 DO
   TIMER = 0
   PAGE WRITE 1
   'cls
   BOX b,cy-b,cx,cx,1,0,0 ' 1mS quicker than CLS
   r = (r + .01745) + 6.283185 * (r >= 6.283185)
   COSr = COS(r)
   SINr = SIN(r)
   FOR x = -30 TO 30 STEP 10
     FOR y = -30 TO 30 STEP 10
       FOR z = -30 TO 30 STEP 10
         denom = x*SINr+(z*COSr-y*SINr)*COSr+100 ' saves about 4.5mS
         xyz = x*COSr-(z*COSr-y*SINr)*SINr       ' this one saves 3mS
         x1 =(xyz*COSr+(y*COSr+z*SINr)*SINr)/denom
         y1 =((y*COSr+z*SINr)*COSr-xyz*SINr)/denom
         PIXEL (s * x1 + cx), (s * y1 + cy), RGB(WHITE)
       NEXT z
     NEXT y
   NEXT x
   PAGE WRITE 0
   BLIT b,cy-b, b,cy-b,cx,cx ,1
   TEXT cx,cy+b,STR$(TIMER)+"mS",cm
 LOOP UNTIL INKEY$ <>""
 
 ' formula before speed refinements
 ' x1 =((x*COS(r)-(z*COS(r)-y*SIN(r))*SIN(r))*COS(r)+(y*COS(r)+z*SIN(r))*SIN(r))/(x*SIN(r)+(z*COS(r)-y*SIN(r))*COS(r)+100)
 ' y1 =((y*COS(r)+z*SIN(r))*COS(r)-(x*COS(r)-(z*COS(r)-y*SIN(r))*SIN(r))*SIN(r))/(x*SIN(r)+(z*COS(r)-y*SIN(r))*COS(r)+100)