From: Brett_A._Letner@notes.up.com
  To  : ggi-develop@eskimo.com
  Date: Tue, 15 Sep 1998 10:00:36 -0600

Graphics newbie

Hi-

I've been looking into the ggi project a bit and have a few questions.
Keep in mind that I have little to no experience with graphics or ggi, so
be gentle.  BTW, some of these questions are not specific to ggi, so
pointers to other documentation is welcomed.

1)  I've compiled and run the stars demo on libggi (since it shows frames
per second), under X with GGI_AUTO sizing, it shows 30 fps, when I increase
the size to say, 1024x768, it slows down dramatically to somewhere around 4
or 8 fps.  What is the major contributor to this slowdown?  Is it:
a)  Slow graphics card?  I have a TGA card running on a DEC UDB (multia)
b)  X is just slow?  Would running kgi instead change this?  What sort of
speed up?
c)  The X target is slow because it copies a whole XImage to the window
each time ggiFlush is called?
d)  My X target is slow because it doesn't use X shared memory or the X
double buffering extension?  I don't know anything about these other than
they are supposed to speed up graphics under X
e)  Other?

2)  How do you directly access the data in a visual?  Is there some way to
do something like memcpy(visual_data_ptr,image_data_ptr,count) ?  A more
general question:  Is there a  way to copy data directly into video memory?
The reason I ask is, I'm attempting to write a game with run length encoded
sprites.  That is, instead of having a rectangular image that is
widthxheight, the images are stored in segments like:  x,y,length,data

3)  Where did you guys find information on programming graphics cards?

Thanks for your time,
Brett