Doomsday Engine

Ok, here's a screenshot: http://koti.mbnet.fi/jeejeeje/wip/doom_flat_tile_error.jpg
and wireframe overlayed: http://koti.mbnet.fi/jeejeeje/wip/doom_flat_tile_error_wire_overlay.jpg

The screenshots are helpful but a small example would be much more useful.

Sure.. here's some little test map (in map01), material definitions and lowres textures in wad: http://koti.mbnet.fi/jeejeeje/wip/sw_testmap.zip

It happens more in areas with non square sectors...

I made a bit clearer example & screenshot of what's going on (also noticed I don't need to write material definitions to use textures as flats or other way around).

I made the floor use the damaged pipe texture, then I made some stairs which made a cut to the sector which creates the tiling error:

http://koti.mbnet.fi/jeejeeje/misc/textest.jpg

http://koti.mbnet.fi/jeejeeje/misc/textest.wad

• http://sourceforge.net/p/deng/bugs/_discuss/thread/059307b6/e0f6/attachment/textest.wad

I did some searching in the source code and found out that textures were aligned to 64*64 grid, but that makes any textures larger than 64*64 align incorrectly.

So I increased the grid size and large textures were aligned correctly as well.

In "edit_map.c" and "static void updateSSecMidPoint(subsector_t *sub)" I simply changed these two lines:

sub->worldGridOffset[VX] = fmod(sub->bBox⁰.pos[VX], 64);
sub->worldGridOffset[VY] = fmod(sub->bBox¹.pos[VY], 64);

to:

sub->worldGridOffset[VX] = fmod(sub->bBox⁰.pos[VX], 512);
sub->worldGridOffset[VY] = fmod(sub->bBox¹.pos[VY], 512);

Which would allow 512*512 and smaller textures to align correctly..

Can you upload a small demo of the problem?