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From: Skybuck Flying on 29 Jul 2010 02:41
(See below for "massive parallel lookup hardware idea, inspired by the old
vga cards")
(The idea is: instead of writing lookups to the graphics card/video
memory/monitor... the lookups become available to the cpu/applications).

There might be a way to do what I want with performance benefits all over...

OpenGL has the ability to seperate vertex, normals, color, texture
coordinates information into individual arrays.

glColorPointer could be used to specify a color/rgba array (for rgba mode)
glIndexPointer could be used to specify a color/index array (for palette
mode)

The nice thing could be that this was part of opengl 1.0 or opengl 1.1...

I am not sure if windows 95 came with opengl 1.0 or opengl 1.1

The dll is called opengl32.dll at least on my system...

Microsoft seems to provide opengl95.exe as well... I am not sure what that
is ? it does say 1.1 is it an update to 1.0 ? I am not sure...

Delphi's old opengl unit does seem to have these two methods which
officially seem to be slight extensions... so even 1.0 or 1.1 had these
extensions already
in place... delphi has a strange way of including these:

The function name seems to be:

PFNGLCOLORPOINTEREXTPROC

Which is really weird looking ;) apperently at the time glColorPointer might
not have been standardized yet ?!?

The unit seems to be from 1991-1993 at least the copyright notice shows...
so seems plausible...

The oldest date I have seen so far is 1981... kinda funny that opengl is
already so old ! ;)

My windows 95 computer is now shutdown... so I can't try this function out
yet... but my bet is it is supported.

This would be great since then I can "upload" all of my vertices just
once... and only have to re-upload the color
as it changes... and then I can do some further optimization tricks.

To-be-continued/investigated ;) :)

Also I am curious if index-mode might work faster on a software rendering...
from what I remember from the dos days writing
to a memory plane was about setting the color index if I remember
correctly... the palette would also be set in hardware..

The hardware takes care of looking up the color indexes and turning them
into actual colors... so at the time... no cpu lookups had to be done.

Quite amazing really since nowadays lookups are a pain/slow... ofcourse they
not really lookups... they are more "writeups"... nothing is returned
to the user/application... instead the lookups are written to the graphics
cards/monitor... so it's more like a "look and write up" ;) :)

I wonder if special hardware could be made for massive ammounts of
lookups... since cpu/memory don't work so well for it...

Maybe some kind of massive-parallel lookup hardware, it will surely be
usefull for something ?! ;) :)

Bye,
Skybuck ;) =D


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