2006/8/21, tok@openlinux.org.uk <tok@openlinux.org.uk>:
> I have got it; quite a lot in there.
>
> Guess I have to try my luck with dosbox, wine and such; last time I
> tried neither m1win nor junction25 were working very well (if I remember
> correctly).

thats weird, since i can run both topdown j25 and 3D beta j25 just
fine, only M1win doesn't work (on xp) for some reason. i sent you old
M1 for DOS in the pack i sent you the url to.

> Thanks for the other tips; now the main problem are the incorrect
> tex-coords. I think I have a pretty good idea why it breaks and a few
> on how to fix it.
> I found the off-by-one in the tile-indices on my own on the same afternoon.

some of your side tiles are rotated, there is no side rotation, sides
only have a bit flag which means "mirror" - no rotations.

cds says about side tiles that bit 5 and 6 in type_map_ext contain the
mirroring:
bit 5 means that textures on north and south sides should be mirrored,
bit 6 indicates same for east and west side of that cube.

> I have started with the g24 files and hit a small snag; I don't
> understand 'palette_index' (so far) and the actual way tiles
> (lid+side textures; not working with sprites so far) index the clut
> isn't working either.  [but don't tell me yet]

the pal_index reindexes virtual palette numbers into actual - physical
palette numbers.

it works like this:

you take tile palette index, you add palette_index

for sprites for example you need to skip clut dedicated to tiles:
pal_index = (g24_header.tileclut_size div 1024)+ activesprite.clut;

for tiles it is just simple, but remember - if it is lid you need to
add side tiles to the number (and side tiles + lid tiles for animation
/ aux tiles):
pal_index[tile number]

please_see_attached_illustration which also shows the palclut visualized :)

> I have put a few new screenshots (after your fixes) up and removed the
> code until I have worked out the license.
> I am soon going on vacation for some time, so there won't be any updates
> for a few weeks. You'll hear from me when I am back.
>
> these already look a lot better
> http://skybound.portland.co.uk/gta/nyc_3d__two_bugs_down_2006-08-21.jpg

In the nyc i can clearly see you are rotating side tiles, where they
shouldn't be, side tiles are never rotated in gta1 (they are in gta2)
in gta1 they just have mirroring flag in type_map_ext.

> http://skybound.portland.co.uk/gta/far_out_2006-08-21.jpg

and i am seeing this right? - the san andreas map on screenshoot -
unless you rotated the camera itself, should be rotated 180° left (i
know how it shouls look, since i drawn entire san andreas map layout
in mspaint with alt + tabbing 7 years ago ;) ).

> http://skybound.portland.co.uk/gta/texture_coords_are_next_2006-08-21.jpg

this looks quite right, but it appears lid rotation is wrong in blocks
where the type_map_ext mirror flags are used.

i have a delphi project written in pascal, which can render all tiles
from g24 files, i can send you whole source code for it, it may help
you understand how g24 files work :)

thats all for now,  and enjoy your vacations! :)


> Best regards,
> tok
>