[cc65] TGI pixel aspect ratio

Hi,

Since it's agreed that the TGI interface will change in the near future,
I think a way for the driver to share the pixel aspect ratio information
with the main program could be a nice addition. For example Atari 
has 1:1, 2:1 and 4:1 modes.

It could be just a signed char, negative values meaning that 
height > width. I know it's mathematically incorrect but it's handy. If
there are platforms with 3:2 or similar ratios, it can be two unsigned
chars, which is even more handy. Neither of them would be a great hassle
to code and maintain.

This way, users can draw circles instead of ellipses once the 
tgi_ellipse function is there, e.g., to draw pie charts and similar. Same
is true for squares and rectangles.

Any thoughts?

By the way, if anyone will ever want a mid point circle algorithm,
my new (and now obsolete, sigh!) one from the Atari tgis is quite 
portable. It calls a function to clip and set the pixel and can be changed
so that it doesn't rely any zeropage variables.

Regards,
Fatih.


      
----------------------------------------------------------------------
To unsubscribe from the list send mail to majordomo@musoftware.de with
the string "unsubscribe cc65" in the body(!) of the mail.