Hi DAVID.

09-Jan-03 09:13:38, DAVID WILLIAMS wrote to JASEN BETTS

 DW> haven't tried it, but won't this over-write itself? It looks to me
 DW> like the rotated image will be superimposed over the original one.

no, it picks 4 pixels in a square that's centred on the screen centre and
rotates their contents by 90 degrees, it does this for all sets of 4
pixels - resuting in the image being rotated.

 DW> routine BSAVEs the screen to disk, then does a CLS before reading the
 DW> disk file and using it to write the rotated image to the screen.
 DW> Also, your routine looks like it will be very slow. But I'll try it
 DW> when I get a chance.  dw

It runs at about the same speed in qbasic (uncompiled), it's probably a
lot slower compiled. (because it point and pset are slow)

give them a fair test -  test them on something with more white in it like
page full of text.. (or numbers 100 to 600)

it will also work in colour modes where bsave has a bit of trouble
(unless you write to the CRTC pagr register)...

also try chaning the for loops to this for a 4 way wipe-fade effect:
instead of the square wipe my original one does.

  FOR C = -239 TO 239 STEP 2
  FOR O = -239 TO 239 STEP 2

 -=> Bye <=-

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