jarrod said:Over on OAF the discussion expanded into which platforms are capable of normal mapping in actual gameplay engines. So far from what I understand it's definitely possible on XBox and GameCube, maybe on Dreamcast, probably on PSP and probably not on PlayStation 2... could anyone tell me why exactly? Pana help! :/
Well from what was said ...Marty Chinn said:That just seems silly. I don't see any reason why normal mapping cannot be done on the PS2.
:thumbsupSpectral Glider said:Quoting Lazy8 for factual information should be a bannable offense.
That's what I thought but nobody would explain anything. They just said "no". :/Marty Chinn said:Well I'm no expert on the PS2 architecture, but in theory couldn't you just use one of the VUs to do dot product calculations?
Reminds me of 'ACM' rendering that suddenly boomed in 1994. A clever technique that revitalises current hardware so to speak.adelgary said:Why wasn't normal mapping applied in video games until very recently? It's like the latest buzz word in the industry.
adelgary said:Why wasn't normal mapping applied in video games until very recently? It's like the latest buzz word in the industry.
Lathentar said:More than likely CPUs/GPUs are finally catching up and able to do the technology while keeping a high frame rate.
Thanks, that makes sense. I remember people saying the VU1 & VU0 can simulate pixel shading fuctions, which is why I figured it could be done on PS2 (with some effort).KickyFast said:To do normalmapping in hardware you need DOT3 support. The PS2 simply lacks this blend mode, but it can do it in several passes.
Normalmapping can be done on the VUs but it's going to be much slower than hardware DOT3. There is however, a fast way of doing bumpmapping on the VU by using paletted textures. Here's a page that describes the algorithm: link
adelgary said:But XBox hardware has been the same since launch
Spectral Glider said:Quoting Lazy8 for factual information should be a bannable offense.
:thumbsup
Marty Chinn said:That just seems silly. I don't see any reason why normal mapping cannot be done on the PS2.
Usage of per-pixel blending effects, such as dot product bump mapping, is an issue of practicality for the PS2. The vector units are focused for geometry transform, crunching through large display lists of polygons - more like a vertex shader than a pixel shader. Emulating a dot product and applying a bump map on the PS2 takes a lot of operations and combinations on the Graphic Synthesizer (it doesn't support those blends), so the crafty techniques even end up taking the PS2 four texture passes and some framebuffer operations to pull it off for a range of lighting scenarios.
There are a lot of games that don't even use two texture passes. Four passes would be nice even for GameCube and Xbox. The PS2 is the lead platform for development in the industry and gets far and away the most software R&D done for it, so the usage of per-pixel blending effects you've seen from the system is a relatively good indicator for what's practical with it.
adelgary said:But XBox hardware has been the same since launch
Scrow said:i see there has already been some links and explantations in this thread, but here's another link on info about normal maps anyway.
http://members.shaw.ca/jimht03/normal.html
edit: Oh yeah, and shantyman, remember that google in your friend ;P