Firsty, check out this: http://www.techreviewer.com/content/reviews/hl2/11_boat_big.jpg Im trying to implement water using HLSL and would like it to be like that screenie. Can someone please explain to me in as much detail as possible how I achieve that affect? Such as, do I use a stencil buffer and render into a render targer which fed into a shader to do fake refraction etc..? Any help is appreciated. Thanks, Meshy

do you have the nvidia SDK?

Yes. Way over my head in every way :)

Quote: Original post by MeshMan
Yes. Way over my head in every way :)

Unfortunately, you do have to realise that HL2's water effects are NOT simple [smile]

From what I've looked at, that style of water comes in 3 core parts:

1. Render whats "under" the water, this will form the refraction later on.
2. Render what's reflected by the water, fairly standard reflection stuff here
3. Blend them together per-pixel or per-vertex depending on the computed Fresnel Term

Obviously, there is more to it than that, but it might give you some direction. Parts 1 and 2 can be fairly straight-forward render-to-texture operations with some clever matrix trickery.

YannL had a few interesting things to say about water rendering:
Lecture On Water
Water reflection and refraction with normal map, without pixel shaders
Reflective surfaces (eg: water)
Water reflections
Bump mapped water
GDNet Article: Realistic Natural Effect Rendering: Water I

Given that, at least the basic components, are from some reasonably simple graphics theory I suggest you read up on the subject - the above links should get you rolling. Once you understand the theory, dig back into your samples and learn how to implement it via HLSL.

hth
Jack

There is a very good article in ShaderX2 that explains how to produce what that looks very much like HL2's water. Actually, that article was out before HL2, so I wouldn't be surprised if the Valve coders referenced it. So, if you have a copy of the book, dig it out and take a look [smile]

It is fairly intensive though, and pretty performance-heavy.

Thanks for the replies guys.
Ive read most of them links that you posted Jeff throughout the entire of today. I'm just having technical difficulties in creating all the objects I need to work with like the reflection matrix, the redner target (which everytime i created seems to always use the image data of a cube map Ive created and wont clear when i call Device->Clear?!).

Water wasn't as simpleas I thought. All these advanced rendering things ive never ever touched on before (I blame the books!).