1. What is Texturemapping ?

Texturemapping is a method of wrapping bitmapgraphics around
vectors or 3D based graphics in common. For games, texturemapping
is mostly used doing very realistic Dungeons.

In contrary to a dungeon like in Dungeonmaster or Eye of the Beholder,
the player is not limited to some few directions, but he can turn
around in TRUE 360 degrees, like in real life. Often the graphics
is more realistic than the graphics of such block graphics games
and especially the opponents of the player are done very well
(using texturemapping and vector graphics ...)

Texturemapping is used for role playing games and for dungeon action
games (some of them able to handle more than one player at the same time).
The most famous such games are Castle Wolfenstein and DOOM. Castle
Wolfenstein is for PC and Mac, DOOM is for PC (and soon for Mac too).
There are probably more texturemapping action games than texturemapping
role playing games.

The original creators of DOOM did no port to the Amiga and won't do
so in the future. All the talk about "Amiga DOOM" is to do a similar
game on Amiga, not the original DOOM. Most people speak of "Wolfenstein
style" and "DOOM style" graphics engines to describe how GOOD the used
texturemapping in a game is. DOOM engines are superior to Wolfenstein 
engines.

2. What are the problems of Texturemapping on the Amiga ?

Texturemapping needs to put single pixels to a screen, not only LINES 
like in vector graphics. So you need both a fast CPU and a fast graphics 
for doing texture mapping.

On PC (and on Mac) the color of each pixel is described by ONE BYTE... 
this is the so-called CHUNKY PIXEL MODE. On Amiga, the color of each pixel 
is described by EIGHT BYTES (for 256 colors). This is the so-called 
BITPLANE GRAPHICS. Easy to understand, Chunky pixel is better for 
texturemapping than bitplane graphics, as bitplane graphics only 
has 12.5% of the speed of chunky graphics. Of course, if you take less
thean 256 colors the speed is better, and i was told, in this way you even
may get a better speed than doing chunky graphics.

Second thing, even if the 68040 is very fast, not everybody has got such 
a thing(i have :)))) ). But on PC most gamers have got a 80486 (Which 
probably is slower than the '040, but much faster than the '020). It is 
probably not possible doing texturemapping with an 68000. In addition, 
texturemapping should have 64 colors AT LEAST (maybe extra halfbrite 
on ECS ...)

Third, a lot of companies let the Amiga alone (Boooooh... :((( ), and in 
special they did not want to risk coding something DIFFICULT on Amiga. 
And some coders simply are moronic DOS-lovers (greetings to ID Software 
(they did DOOM) and to Richard Garriot of Origin at this place... i hope 
they $"&$/&$"/$"/& (censored) !!!)

3. How can they be solved ?

A) Copper Chunky Modes

I told you before, that the Amiga is not capable of doing chunky modes. 
That is not 100% the truth. There is a type of copper cheat (the copper 
is one of the Amiga's graphics coprocessors), that in fact DOES chunky 
modes. The problem with this graphics mode is, it can only handle a 
resolution about 100x100 to 130x120 pixels (i do not know exactly, as i 
am no specialist in coding texturemapping ...) Compared to PC Games with 
320x200 texturemapping this may look ugly ... (but it should be mentioned, 
games on PCs (at least on PCs that are not these absolute high-powered
ones...) often do not use full screen graphics, and so often too use such 
resolutions. Copper chunky can't do 1x1 or 2x1 pixel resolution or
something like that (i do not know exactly what are the limits for that
Copper tricks... maybe an expert inc coding such things could tell me ?)

B) Chunky to Planar Conversion Routines

A Chunky to Planar Conversion Routine is a part of a texturemapping code, 
that takes graphics in chunky (one Byte per pixel) as input, and puts it 
as Bitplane Graphics on the Screen. Of course, this method needs much 
CPU-power. For most demos/games, you should have at least a '030 to get 
it smooth... and a lot of demos using this technique do not have FULL 
texturemapping... that is, they for example have no stairs, and everything 
on screen is on the same height level. Copper Chunky does this better, but
has a low resolution... of course a '040 with a Conversion Routine can 
do fine things...

C) Using a graphics board

Graphics boards for the Amiga do not use Bitplane graphics, but, in fact, 
Chunky graphics. The problem is, not many people have such boards in their 
systems, in difference to the PC, where all graphics is based on such 
boards. But some coders said, they maybe will do an additional "graphics 
board version", that features the fast graphics chips with their chunky 
graphics... there is even a texturemapping demo running on EGS (EGS is
a standard for Amiga graphics boards).

D) Demo-Groups do the Games

As those people who can do texturemapping best (on PC) often are 
DOS-lovers, on Amiga a lot of people of the demo-scene and others, who 
are not employed at software firms, began to code... and as software firms 
want to SELL, they will probably sell the finished products, even if they 
are Amiga-only... And of course there are firms DEDICATED to the Amiga, 
like Team17 ... they are in this texturemapping business, too ...
