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PureSpider
10-18-2008, 07:12 AM
Hi all!
I wanted to know how it's possible to do SSAO (http://en.wikipedia.org/wiki/SSAO) with GLSL...
I know it is possible, found that site regarding this point:
http://rgba.scenesp.org/iq/computer/articles/ssao/ssao.htm
Now the point is... I'm just too new to GLSL to convert that programm to use it with my scene... can anyone help?

PureSpider
10-19-2008, 04:12 AM
Okay I think it'll be okay if I just get the z-map in real time...
Still don't know how to do this with GLSL :p
Can anyone help me?

kroneml
10-19-2008, 05:04 AM
I recently did some sort of SSAO-implementation using OpenGL/GLSL.
You must render your depth values to a texture (offscreen render pass) and then use this informaton. You will need framebuffer objects.

PS: I think SSAO is not really beginner level, maybe this should be moved to the advanced section? ;-)

PureSpider
10-19-2008, 05:46 AM
Yes thats what I figured but I didn't manage to use my depth values, only render them.
When I try to shift them x or y wise on the texture, nothing happens...

€dit: OH! I just noticed the tex coordinates are between 0 and 1... shifting works now :)

€dit 2: How can I get more that 8bit z-maps? Like 32bit or such?

PureSpider
10-20-2008, 07:01 AM
How can I get more that 8bit z-maps? Like 32bit or such?
Anyone?

Sorry for bumping but I really need it =/

kroneml
10-20-2008, 07:15 AM
I recommend looking at the NVIDIA SDKs (http://developer.nvidia.com/page/home.html), the are a really good resource for this! Especially the "Simple Framebuffer Object" from SDK 9 and the "Christmas Tree" from SDK 10 provided a lot of help on this topic! Plus, you can mess around with their code and see what's happening! ;-)

PureSpider
10-20-2008, 08:21 AM
Already did so with RenderMonkey... the ATIs part of the game... I just can't get my z-maps higher than 8bit :(

dletozeun
10-20-2008, 01:06 PM
Just to be sure, by z-map, you mean depth buffer?

What hardware, OS are you working on? How do you know that your implementation supports only up to 8bits precision?

PureSpider
10-21-2008, 05:52 AM
Yes I do.
I'm working on Win XP 32bit with an ATI X1650Pro 256MB.
I don't really think I'm limited to 8bit but I just dont know how to get more out of the z-map :p