I'm sure I've navigated through a room with lower gravity than its surroundings before. Something like... gmsp1? Did that have its own progs? 

i think it was in the start map of hipnotic 

gmsp1 in the outside area. 

yeah, but you don't have full swimming/noclip-style control, only standard quake air-control which is limited. 

i wonder...

what if you turned noclip on the player, then created a dummy entity with player bbox size.

then, transfer any movement the player is trying to do to the dummy and reset player's position to the dummy every frame.

this gives you full noclip control but you won't be able to go through walls or entities because your actual position is bound by the dummy entity. 

.. it does not requires qc, I am happy with any solution. As I am definitely a bad coder, I'd rather prefer to prevent from trying to code anything, and stick to existing mod/std Quake...
Well, now I have to figure out how to make all this as easy as possible... If not easy at all, no space map, I'll do something else...
and to be honest, I didn't started any piece of brush placement yet, I am just experimenting zero gravity stuff: I want make sure the effect will be realistic enough before thinking about map architecture (despite I already have an idea about what I want)
Anyway, thanks a lot for the hep. 

The hipnotic progs.

I think it works with a trigger_gravity or something like that.

Easy peasy. 

1/ Water tint is still present despite wateralpha set to 0
=> Is it possible to remove it and make water as transparent as space emptiness ?

Have you tried gl_polyblend 0? 

@ijed: I know Quoth has already a trigger_setgravity that can be used for low-g area... that is coming from hipnotic progs ! After some experimentation I made recently, it is acting exactely like sv_gravity, hence the player cannot move up and down like I'd like to.. anyway, thanks to remind me this stuff.

@ontruepurple: I tried it, and it works perfectly ;) Thanks a lot for the clue ! no remains the sounds issue :D 

I tried replacing the water related sounds by mine, but it failed pathetically with a message claiming I was not using a registred version of Quake...
Actually I tried to add a sound/player folder in which I put empty files in place of some of the related water wav files, keeping the original name... I don't know wether it is like this you were thinking about sound replacement: can you elaborate how you would do it please ? 

replacing the excisting wav files by silent ones with the same name...? 

well, first, an important thing is to vis your map (using aguire's vis) with -noambientwater. this stops the engine from playing the ambient water sound.

next, make silent sounds for:
misc/h2ohit.wav
misc/outwater.wav
misc/water1.wav
misc/water2.wav
player/h2ojump.wav
player/inh2o.wav
for these sounds, just copy misc/null.wav (in pak0.pak) and rename it.

now, you will need to make some custom sounds for these:
player/h2odeath.wav (maybe just replace with a normal death sound)

player/drown1.wav
player/drown2.wav replace these with maybe normal pain sounds or maybe the doom3 vacuum choking sounds.

player/gasp1.wav and gasp2.wav... maybe can be left alone. 

are that real waves with data of silence,
or just files that have that name but consist nothing, like changing an empty *.txt file into a *.wav? 

they are just sounds that are very short and silent.

if you put a .txt file, it will not have the header information that denotes a .wav file and you'll probably at the very least get warning messages or even crash the engine as it tries to read the thing. 

Thanks, now it is clear ;) 

just make sure that you package it as a separate mod, like i said earlier, instead of dumping stuff in the quoth folder otherwise it'll mess the sounds up for maps that don't use water as vacuum. :) 

in any case this sounds very interesting :) 

Thanks a lot for all these good advices. I now have to build the mod for this, and start the map.. I have a rough idea about what I'll do, but nothing clear today... And if it gives idea to other mappers, it is even better ;)
Again, thanks a lot for your support :) 

S_FindName: out of sfx_t
at map loading.

o_O 

Apparently means that you've tried to precache too many sound effects. The limit is 512, which is twice as generous as for models. You have some lengthy conversations going on? 

thanks :)

how do you find out these error meanings? are you actually looking through the source? 

is that fitzquake? Seems like it should handle that more gracefully. I.e. if you haven't exceeded max_sounds, it shouldn't fail in other ways. 

well, it was quakespasm085.4
i'll try to remember to test it in fq085 tommorow. 

Yeah, it's often easier to google the error and find a result in a quake engine svn directory. This time it was easier because it's an error people used to run into in Sven Co-op. 

i guess i should try the self help a bit more eh? :P

it was just such a strange error that i kind of laughed and just posted it.

thanks!