it that time of the year again and i've once again picked a track that i feel could use a little graphical update. this time it's laguna seca - beautiful and challenging track. same goes for the texture creation process.
so far i'm done with the asphalt and the grassy bits..
so when i went to do a quick new wiremesh fence texture (2048x1024) - and yes, i know smaller would be better, but the rig can handle it, ... . quick being only the part where i created the actual graphics from scratch, like the partly rusted fence poles and then wiremesh. that took an hour or two... so when i was done with all that, i decided that a wiremesh fence would be really nice if it actually was see-through, read transparent. and that's where all the trouble started. creating an alphamap was easy enough. and i chose to do it as a black and white only transparency map - no fancy gradients (yet). so then i fired up mipman.. great tool, but it would not create a usable mip. hmm.. some fiddling around with it - and an actual brief reading session of the readme that came with it made it obvious 256 pixels is the limit. bummer, i would need 8x times, at the least 4x times. well on to the next tool: winmip.
while winmip is a tool i really like and basically use to convert all my textures from .bmp to .mip in, it somehow will not do what i want it once transparency is involved.
here's what happens:
i did my texture in such a way, that i filled the background with a flat green back (rgb: 0,255,0), so that i would have an easy choice for a transparency color. so then i load my 24bit .bmp with the texture in it into winmip, change the type to mip, subimages 7 (as is my custom), mapping to 0. and then there's the choice what type of mip to create - and frankly, i tried them all. say i go for type 4 and via click or shift-click (as it seems to do the same anyway) i select the green background color easily enough. so it shows up in the tiny box and all is well. so then i save the .mip file, copy it into the track directory and start gpl... almost all is fine then. the texture loads, it has a transparency in it - even where i wanted it, BUT what's with the green outline around everything? DOH!
i tried other ways - no go.
so how can i use winmip to that effect? if anyone has pointers, it would be greatly appreciated. same goes for seperate transparency maps - as i already created one, i'd like to use it, but have so far not been able to load both the texture .bmp and the transparencymap .bmp into winmip to create one .mip that includes both. also how would i go about this process if i want to create a texture that has transparency gradients? that is a proper mystery to me. i would like to create a few trees of the like you see in battlefield (if anyone of the racing community even knows that game - the trees really rock! if not the game itself) for this king of racing simulation, but so far.. no deal. always off colors or no transparency at all... i'm clueless as to what i'm missing here. are there other tools out there? i'm using photoshop cs, winmip 2.16.6 and/or mipman.
- i can post pictures of the track as it is right now and off the worrying texture issues as well if need be.
thanks to a fairly long earch at rsc, i was able to locate a tip that got rid of the fringing issue - simply use color 51,51,51 (r,g, as the backgroundcolor to be made transparent later. for the fence i did, this works well enough, but i guess once i will be into the trees, quite literally even, a single transparent color won't do anymore. i'm guessing i would need 16 colors for that, so a real alpha-transparency map will be needed.
is there anybody out there who can shed some light on the workings of that?
or if possible, if someone has a detailed description of the .mip-file format, i may get it in my head to unearth my old programming tools and write a converter myself. it's been know to have happened before and after all a dosbased tool isn't that hard to write...
dangermouse EDIT: Changed title of thread to attract attention.
Edited by dangermouse, 26 August 2006 - 10:26 AM.