Tileable textures
Claudio Santia`
Hi games developers,
I'm writing a flight-sim style game and I'm in trouble in creating tiled
bitmaps for the terrain textures. I need textures for rock, forest,
grass, snow and similar. Anyone knows of freeware textures I can choose
from?
I'm also interested in algorithmically generated textures. I've seen
that Corel Photo-Paint 5 has a nice fractal textures feature. It does
most of what I need, with the exception that the textures are not
tileable. Does anybody know which algorithms are used? Any pointer to
some info regarding fractal tileable textures algorithms?
Thanks in advance.
--
----------------------------------------------------------
----- Claudio Santia` c_sa...@net4u.it -----
---- ----
--- 3D Graphics Programmer ---
--------------------------------------------------
gu...@conmat.phys.soton.ac.uk
In Article <32337A...@net4u.it>
Claudio Santia` <c_sa...@net4u.it> writes:
>Hi games developers,
Hi
>I'm writing a flight-sim style game and I'm in trouble in creating tiled
>bitmaps for the terrain textures. I need textures for rock, forest,
>grass, snow and similar. Anyone knows of freeware textures I can choose
>from?
I am also interested in finding sources of natural looking landscape
textures (viewed from directly overhead) - any pointers would be greatly
appreciated.
>I'm also interested in algorithmically generated textures. I've seen
>that Corel Photo-Paint 5 has a nice fractal textures feature. It does
>most of what I need, with the exception that the textures are not
>tileable.
After asking the same question I also went down the same route and had the
same problems (surprise, surprise). However, I did get on very helpful bit
of advice with regard to making textures tesselate smoothly. What you need
to do is to take your tile and then shift it so that the four quadrants lie
in a cross in the middle of the tile rather than at the edge.
i.e take your normal tile. [With the four quadrants marked as shown]
A--B--C
| |
D E F
| |
G--H--I
and shift it so that it is like this
E--FD--E
| |
H IG H
| |
B--CA--B
Then smooth the joins along the central cross shape [+] (F-I-C (or D-G-A) and
H-IG-H) using an art package. To get back to your original layout (but
which will now tesellate) simply reapply the shift you used before.
Your tiles will now tesselate. This is obvious when you think about it,
however, is perhaps the simplest way of going about making your tiles
tesselate smoothly. It may seem like a bit of hassle to write some code
which does the sprite shift but once done it's very useful. I was lucky,
someone wrote such a routine and made it PD so I just had to drag and drop
my sprite files onto the inconbar icon and then touch them up, however, I
use an Acorn RPC (and Risc OS) so the utility would be of no use to you.
>Does anybody know which algorithms are used? Any pointer to
>some info regarding fractal tileable textures algorithms?
Not sure about this one. Once again if you get any useful answers then could
you let me know.
>Thanks in advance.
cheers (and hope it helps),
Max Palmer
--
Max Palmer : PhD Student : email ---===> m...@sousun.phys.soton.ac.uk
gu...@conmat.phys.soton.ac.uk
In Article <513bgu$h...@fu-berlin.de>
gu...@conmat.phys.soton.ac.uk writes:
>In Article <32337A...@net4u.it>
>Claudio Santia` <c_sa...@net4u.it> writes:
Woops, made a bit of a mistake in my previous post.
>i.e take your normal tile. [With the four quadrants marked as shown]
>
>A--B--C
>| |
>D E F
>| |
>G--H--I
>
>and shift it so that it is like this
>E--FD--E
>| |
>H IG H
>| |
>B--CA--B
The above diagram is wrong, it should look like this
E--FD--E
| |
H IG H
B CA B
| |
E--FD--E
cheers,
Claudio Santia`
gu...@conmat.phys.soton.ac.uk wrote:
>
> In Article <32337A...@net4u.it>
> Claudio Santia` <c_sa...@net4u.it> writes:
>
> Hi
>
> >I'm writing a flight-sim style game and I'm in trouble in creating tiled
> >bitmaps for the terrain textures. I need textures for rock, forest,
> >grass, snow and similar. Anyone knows of freeware textures I can choose
> >from?
> After asking the same question I also went down the same route and had the
> same problems (surprise, surprise). However, I did get on very helpful bit
> of advice with regard to making textures tesselate smoothly. What you need
> to do is to take your tile and then shift it so that the four quadrants lie
> in a cross in the middle of the tile rather than at the edge.
[In-dept explanation of method snipped]
A few days after my post I realized a similar method. Using Corel Photo-Paint
(but it is possible in any similar program) I just take a few top rows and merge
then with the bottom rows, in reverse order. The same is done with some of the
left columns which has to be merged with the correspoding columns at right. The
effect is similar to that of your method but does not involve any image
shifting. I use to move three blocks of two rows/columns and to give them a
transparency of 25%, 50% and 75% respectively. On 256x256 textures the effect
is good enough to no more distinguish the original image border.
Bye