Re: AppleWin and graphics

["Jeff Blakeney" <jeff.blakeney@a2central.com.remove-675-this>]

  To: Guillaume Tello
On Wed, 7 May 2008 12:38:18 +0100, Guillaume Tello wrote:

>     I solved my problem, but don't know why it is that:

I too don't know why this happens.  Perhaps it has to do with the way
double hi-res is enabled that is keeping HGR2 from being cleared.

>     if my screen is in 80 col (PR#3), then HGR2 doesn't work correctly.
>     But if I turn it back to 40 col (with Esc "4") then HGR2 works 
> perfectly. I there a way, within a program, to turn the screen to 40 col?

I just tried HGR2 while running KEGS and it does the same thing.  If 80
column firmware is active in 80 column mode, then HGR2 turns on the HGR2
screen but doesn't clear it.  If the 80 column firmware is active but
only in 40 column mode or if the 80 column firmware isn't active at all,
HGR2 activates the HGR2 screen and clears it.

Another thing I found is that if you have the 80 column firmware active
and are in 80 column mode, if you do an HGR before you do the HGR2, the
HGR2 screen is activated and is cleared.  This means you have two ways
of solving your problem in your program.  Either do this:

10 REM activate 80 column firmware and go to 80 column mode
20 PRINT CHR$(4);"PR#3"
30 REM activate HGR2 screen and blank it
40 HGR
50 HGR2

Or you can do as you requested above and go back to 40 column mode with
this code:

10 REM activate 80 column firmware and go to 80 column mode
20 PRINT CHR$(4);"PR#3"
30 REM activate HGR2 screen and blank it
40 PRINT CHR$(17)
50 HGR2

If later in your program you want the 80 column screen back you can just
use PRINT CHR$(18) to switch from 40 to 80 column mode.
--- Synchronet 3.14a-Win32 NewsLink 1.85
A2Central.com - Your total source for Apple II computing.