Newsgroups: comp.windows.ms.programmer
Path: utzoo!utgpu!watserv1!sunee!gpsteffl
From: gpsteffl@sunee.waterloo.edu (Glenn Steffler)
Subject: Re: animation in Windows?
Message-ID: <1991May19.152505.11357@sunee.waterloo.edu>
Organization: Gold Disk Inc.
References: <1688@anaxagoras.ils.nwu.edu>
Date: Sun, 19 May 1991 15:25:05 GMT
Lines: 54

In article <1688@anaxagoras.ils.nwu.edu> neves@aristotle.ils.nwu.edu (David Neves) writes:
>
>We want to do some simple animation in Windows.  If anyone has some
>pointers on this I would appreciate them.

This is a topic which most programmers find difficult in Windows due to
the "uncommon" choice of API for bitmapped video.  An easy way to draw
a particular bitmap to the screen is BitBlt ().  Unfortunately the
Windows graphics primatives provide only a source bitmap device a
destination bitmap device and a SMALL (is that in caps or what?!)
pattern bitmap.  The pattern bitmap determines what parts of the source
will be copied to the destination (hey lets just deal in these terms as
a new developer may not realize the multitudinal useage variety
provided by ROP modes -ed).  Like I said, this pattern bitmap is a
small 8x8 bitmap (actually it's a brush) that is selected before the
drawing operation.

The only way to draw a non rectangular shape is to "erase" the destination
in those areas that are going to be changed, and joining (as opposed
to copying) the source bitmap with the destination bitmap using SRCPAINT
(or whatever...don't have manuals on me, or near me for that matter :-)

There are certain companies (not saying Gold Disk is one of them, and
likewise not denying it...) which could provide an authoring system
(video based in Gold Disks theoretical case) for animations in
Windows.  Anyway I think I should reserve any further...
***<paragraph halted due to big mouth>***

>One way we are considering is to prepare several bitmapped objects and
>bitblt them (using BITBLT) to a complicated bitmapped background.  The
>problem as I perceive it is how to specify the part of the bitmap you
>want copied to the screen.  For example, lets say you have a donut
>picture and want to send it to the screen.  The bitmap of the donut is
>rectangular but the object is circular and it has an interior circle
>that also must show the background.  Is there some secret transparent
>color that one can use to construct the bitmap?  Or?

Quick answer...NO.  Longer answer would ask you to phone those 
nice people at Microsoft and inquire about the Multimedia Toolkit
or Developement Kit for Windows.

>
>-thanks, david
>--
>neves@ils.nwu.edu
>Institute for the Learning Sciences, 1890 Maple, Evanston Il 60201

Take Care!

-- 
Windows Sumo Wrestler                "Bo doesn't know software" - George Brett
  --(Windows 3.0, a combination of modern moodring technology and voodoo)--
"I guess she had a way, of making every night seem bright as day"
`I Don't Believe In Love`   -Queensryche (Oper. Mindcrime)     Glenn Steffler