🚀 go-pugleaf

In article <1990Dec17.033055.3516@marlin.jcu.edu.au> glmwc@marlin.jcu.edu.au (Matt Crowd) writes:
>Hi, I have a couple of questions...
>
>1)  How does one get the 2.0 standard file requestor to appear on your
>own custom screen? I have it appearing on workbench at the moment.
>Example code would be nice!

use the {ASL_Window, mywindow} tagitem-pair when calling AslRequest() or
AllocAslRequest().  The requester will appear on your window's screen.

>2)  What happens if a PAL picture is loaded into a NTSC machine? Does
>the picture cut off at the 200 line mark?  There is a bug in my machine
>that causes it to boot sometimes in NTSC instead of PAL, and on one
>of the occasions it did, I loaded a PAL picture.  The picture extended
>down past the 200 line mark (maybe 20 lines or so), even though the
>mouse could not be moved below the 200 line mark.  Is this what happens
>on a _real_ NTSC machine?  

Remember that the IFF-viewer is opening the screen based on its
understanding of the picture's mode.  A 2.0-aware program can
very easily open a PAL or NTSC screen depending on what' appropriate.
If you just say "give me hires" or "give me hires-lace", etc., you'll
get a screen whose size depends on whether the machine is jumpered
to NTSC or PAL (or fixed to NTSC or PAL for older Amigas).

What happens depends on the software in question.  I think our Display
program knows everything there is about modes a picture was saved in.
You can use ScreenMode to change your Workbench to either PAL or
NTSC.  (Note that your machine is still PAL even if the Workbench
is in NTSC).  We know of no bugs that cause a PAL machine to boot
as NTSC.  Do you have a hardware problem?  I wonder what would happen
if the NTSC/PAL jumper was loose or missing.  Check the jumper which
is just adjacent to Agnus.  I don't know the jumper number, but on
later motherboards, it's labelled "PAL/NTSC".

>3)  Is the OS supported solution to determine whether a program is 
>running on NTSC or PAL -
>
>	if(GfxBase->DisplayModes & PAL)
>		printf("PAL\n");
>	else
>		printf("NTSC\n");

Depends for what use.  Some programs may try to jam this flag to
change the "type" of machine (not a supported concept).  In general,
this bit should reflect the hard-state of the machine, i.e. whether
it was born or jumpered NTSC or PAL.

Under 2.0, to be more precise you can GetDisplayInfoData() on any basic
mode, like HIRES_KEY, and check the DisplayInfo.PropertyFlags DIPF_IS_PAL
bit.

>Will this work on NTSC machines that are running PAL under 2.0?

NTSC machines with PAL workbenches are still NTSC machines.  They
should normally report "ntsc" through any correct test.

If you use GetScreenData() to learn about the Workbench, this call
may lie about the Workbench screen if it's at all unusual.  NTSC
machines will report NTSC Workbenches, and PAL machines will report
PAL Workbenches.  (The reasons for all this lying are involved.)
Under 2.0, use LockPubScreen() to figure out the true dimensions and
mode of a screen.
>
>-- 
>Matt Crowd    
>Email Address    glmwc@marlin.jcu.edu.au


     Peter
--
     Peter Cherna, Software Engineer, Commodore-Amiga, Inc.
     {uunet|rutgers}!cbmvax!peter    peter@cbmvax.commodore.com
My opinions do not necessarily represent the opinions of my employer.
"Oh, PIN-compatible!  I thought you wanted me to make it IN-compatible!"