[Bug] Tracker music in .MOD format doesn't play

[andromeda-dsda]

Hey again,

I've noticed recently that tracker music in the .MOD format doesn't play in this fork, while it plays fine in the latest version of regular PrBoom+ (both the stable and test versions). Other formats of tracker music I've seen used in wads (.S3M, .XM, and .IT) play correctly, so it's an issue specific to the .MOD format.

NoReason's Speedmaps 2 is an example of a wad that uses some tracker music in the .MOD format, including its D_DM2TTL lump, so it should be easy to compare the behaviour difference between the aforementioned PrBoom+ versions.

Thanks in advance and keep up the great work!

[fabiangreffrath]

This might as well be due to the used MOD rendering library (i.e. libdumb).

[alexey-lysiuk]

DUMB 2.0.3 doesn't work correctly indeed. Version 0.9.3 seems to play MOD files fine.

I guess, support for 2.x was never completed in the original PrBoom+.
Maybe unrelated, but duh_render() function is marked as deprecated.

[fabiangreffrath]

Does it help if we replace DUMB_MOD_RESTRICT_OLD_PATTERN_COUNT with DUMB_MOD_RESTRICT_NO_15_SAMPLE or even 0 here?

prboom-plus/prboom2/src/MUSIC/dumbplayer.c

Line 147 in fdbd0a8

duh = dumb_read_mod_quick (dfil, DUMB_MOD_RESTRICT_OLD_PATTERN_COUNT);

[fabiangreffrath]

The values may even get ORed, so 3 is also valid.

[alexey-lysiuk]

It works with DUMB_MOD_RESTRICT_NO_15_SAMPLE, and with 0 too.

[fabiangreffrath]

From looking at readmod.c:it_mod_load_sigdata(), I conclude that setting this to 0 will correspond to the old libdumb 0.9.3 behaviour.

[fabiangreffrath]

@alexey-lysiuk Would you like to adjust this in the code?

[alexey-lysiuk]

Done. It would nice to know why that flag was used for DUMB 2.x though.

[fabiangreffrath]

I introduced that change back then but don't remember why, honestly.

[fabiangreffrath]

This provides some insight into this issue: kode54/dumb#86

Upstream recommends setting this to 1 which would invalidate 15 sample modules, but since this restriction wasn't in libdumb 0.9.3 before, either, I guess we play safe with leaving it at 0.