Setting a 1:1 perspective tells GL to make x=y in units even though the ratio is 1.33:1 in the display. By not doing this rectangle 1 1 would be drawn to match the 4:3 ratio of the window (although the default in GEM is x=y so you have to change it to something other than 1:1 to have this happen).
<br><br>The test2 patch resets some of the ratios to 1:1 so the perspective corrects that back to fit the window, otherwise the square is taller than it is wide.<br><br>Hopefully I didn't make this more confusing.<br>
<br><div><span class="gmail_quote">On 5/13/07, <b class="gmail_sendername">cyrille henry</b> <<a href="mailto:cyrille.henry@la-kitchen.fr">cyrille.henry@la-kitchen.fr</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br><br>chris clepper a écrit :<br>> You are wondering why a 1:1 perspective works for a 4:3 window?<br>><br>yes.<br><br>cyrille<br><br><br></blockquote></div><br>