Bump Mapping in Blitz 3D, HOW?
Blitz3D Forums/Blitz3D Programming/Bump Mapping in Blitz 3D, HOW?
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| The original demo seems have dissapered, can anyone tell me how to use my bump map with my model in Blitz 3D. While I'm here how should I combine and ambient and a diffuse texture? I wish there was some documentation for these commands even if unofficial. It's very frustating stabbing around in the dark. Thanks, Darkheart |
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| Hmm well I kinda worked it out on my own but TBH I'm struggling to tell the difference with and w/o the bump map. :\ Darkheart |
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| Blitz doesn't have bumpmaps, and I suspect that repeated posts to the contrary are part of the reason for this confusion. It has normal maps, which are really nothing like bumpmaps ( particularly to look at and to generate. ) Normal maps are not greyscale and have to be generated with a proper tool. ATI have a tool in their developer section, there are plugins for some packages and there are a couple of standalone programs, but you can't just go ahead and paint one, and converting from a bump map to a normal map is less than perfect. The ideal way to create normal maps is with high polygon geometry and a low polygon version of the same model to apply the normal map to. You also need to colour the vertices of the object with a color which represents the position of the lightsource you're using ( 1 max. ) That's about all I can remember off the top of my head. If you need more assistance, I'll see if I can find the code someone posted on Blitzcoder. I think I kept it on a cd somewhere. |
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| Bugger so actual bump maps are totally useless? So if I create a normalmap with the ATI tool then use vertex colours instead of a texture I can get a higher render? Darn, I just wanted convincing bumps. Darkheart |
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| Traditional bump maps are totally useless, yes. You can convert them, but they don't work too well. I haven't tried the ATI tool, but I believe it requires two versions of the model, one with high polycount, and one with low. It then renders the map to reflect the contours of the high poly model on the low poly model. I think you can get away with entitycolor rather than vertex colours, but I could be wrong. |
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| "you can't just go ahead and paint one" -Sybixsus Wrong- I've painted a few, you'd be suprised how easy it is after you manage to wrap your head around the concept. ^_^ |
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| Semantics. It's an image, so obviously you CAN paint them. They're not comparable with the kind of normal map you can generated with high poly geometry. |
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| Mine are (that's not a lie), bwahahaha! ;) |
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| You lie noel!!! ;) |
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| Check my sig for an example! It can be done with only changing the entity color, but that requires the dot3 maps, to be generated in a different way! |
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| And what way is that Fredborg? Does this have something to do with Tangentmaps??? |
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| The maps need to be using 'world space normals', if you want to do it with entity color. I think the demo with the statue Rob posted some time ago, used that technique. The one in my example uses 'local space normal maps', which means the color for each pixel in the map is calculated as an offset compared to the normal of the triangle it is applied to. I don't know if these are the right names for it :) |
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| Hey Fredborg could you give me a little idiots guide to your Dot 3 example and maybe suggest how I could use it for what I'm doing. I want to use the bumpmap to add detail to a mesh I'm using as the terrain for my level (but it's a mesh not a blitz terrain) this also helps me with level editing. To avoid using many, many, 1000's of polys I thought I would use a quite basic mesh (8000 ish) and then add a bumpmap to it for the detail and to make it look realistic. I will post my media later. Darkheart |
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| The one in my example uses 'local space normal maps' I think that official names are "object space" and "tangent space" normal maps. [yes, I'm a nitpick :P]. Blitz uses (as far as I have understud) object space ones which are not that useful and cannot be "recycled" like tanget space ones. |
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| This is a good link on DOT3: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dndrive/html/directx11192001.asp L8r, |
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