Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!agate!helios.ee.lbl.gov!nosc!manta!dwi
From: dwi@manta.NOSC.MIL (Steve Stamper)
Newsgroups: comp.sys.amiga.tech
Subject: VSprites don't show
Message-ID: <866@manta.NOSC.MIL>
Date: 7 Jul 89 14:02:04 GMT
Reply-To: dwi@manta.nosc.mil.UUCP (Roger Uzun)
Organization: Naval Ocean Systems Center, San Diego
Lines: 37

I am using the standard Amiga GEL system to animate 3 BOB's
and 1 VSprite on a 320X200 64 color ExtraHalfbrite, double
buffered display.  I have done this a lot with BOB's and have
done programs with VSprites before but for some reason the
VSPrite in this program does not get drawn.  When I traverse
the GELSINFO structure I see it on the list, but it is not
being drawn.  
All BOB's behave normally but the VSprite is not there.
To set up the VSprite I basically do the same things I do to
the VSprite structures for the BOB's except:
1) Set the VSprite->Flags structure to VSPRITE for the Vsprite
   and to SAVEBACK|OVERLAY for the BOB's
2) set the VSprite->SprColors field to point to a 3 word array
   containing {0xfff,0xfff,0xfff} so that it will be all white.
   (of course I have tried other colors too, just to see if
    it was somehow blending into the brown background, but no go)
3) Set the VSprite->Width to 1 the VSprite->Depth to 2 and the
   VSprite->Height to 16 (I have Imagedata, and the masks set up
   for this size as well).  The Bob's have depth of 6 and differing
   widths and heights but they are all fine.
4) For the VSprite, PlanePick and Planeonoff are set to 0
   the VSprite->VSBob field is set to null.

I do not use Morerows or any overscan, The program seems to run fine
except for the VSprite is not there.
I add the bobs using AddBob(Bobptr,rp) and add the
VSprite using AddVSprite(Vsp,rp).  
Am I missing something, must I set up my GELSINFO structure any
differently?  I tried inserting the ON_DISPLAY ON_SPRITE macros
in the redraw section, it made no difference (they are unnecesary
with SortGList()DrawGList()MakeScreen()RethinkDisplay() since
ON_SPRITE is the default for the system).

Any ideas why a VSprite could be added to the GEL List and not
drawn?

-Roger