Models by macuser

[macuser]

Ah thanks jorzi. however if i do not do the mesh stuff the imported obj is not a mesh just an object without a mesh (in other words i cant' get into edit mode) yes i do know about uv unwrapping but have not done it in blender before.

[Jorzi]

Hmm interesting...
Oh well just do whatever works

[macuser]

here is the lowpoly for you berg

[macuser]

since my PC is out of action right now i want to learn more about blender. I am trying to bake an AO map from one mesh to another. Does anyone know how that is done in blender? THNX

[Remotehorst]

First you need to create a uv map for the object. Ok lets do it

Tab into edit mode.
Place your seams (Ctrl +E) to the selected edges to provide a better unfolding of the mesh.
After you have done that you press U and select Unwrap.

Now you only need to open the UV/Image Editor in another window and create a new image with the size and options that you want.

Set up your Ambient occlusion in the world options. (The button with the little blue earth in the buttons menu).
Ambient occlusion in blender can be very annoying if you dont know how to set it up. Once you understood how to, its very easy

There is one field called World. There you should change the two colors and in preview swich to blend.
This colors will have an influence to AO and provide a nice atmosphere if well chosen.

Best effects with AO you get if you set it from Raytrace to Approximate and set Passes (sometimes no need to) to 1 or 2. Use the Pixel Cache and swich on the button "Both". This lightens and darkens.
Now set it from Plain to Sky color and test if "Energy: 1" is ok.

To finally bake the AO go to the scene Buttons (F10) and choose what you want to bake.
The Margin value creates an automatic texture margin. Thats very usefull for games.
Because if the margin is 0 you see weird artefacts if the model is zoomed out a bit.

With 2048 textures you should use a minimum margin of 10 pixels. Maybe some more would be better.
Press "BAKE" and you are almost done!

Now you only need to select your lowpoly, Tab into edit mode and (best select all with A) open the UV Image editor. You only need to choose the Baked image and you should be done.
To make this work the highpoly model has to be made out of the (already unwrapped) lowpoly!
I hope you done it like that. Because if you have two different UV-maps you need to manually adjust the lowpolys UV to fit the baked image.


If you got any questions feel free to ask me.
I cant wait to see your model baked

I always bake the full render. IMHO you get the best results with that.
Because blenders capabilities in texture creation are wicked!
If you bake full render too, dont forget to swich the lights raytracing off.
Place 4 lightsources around the model with a intensity of 0.5 or so. The color should be almost white with a tiny little bit of orange. sometimes its usefull to even place lights directly near the object to create lights on textures.
Here you can see the big ship with this effect: (scroll down a bit)
viewtopic.php?f=6&t=7007

Have fun!

[macuser]

i already know how to bake the AO (thnx for the extra info and tip though) I wanted to know how to bake it from a highpoly mesh to a lowpoly mesh.

[Remotehorst]

Edited my post. Information is there now.

[macuser]

ah, thank you

[Remotehorst]

There is also a different (maybe easier method).
If i remind well, you need to select the highpoly and then add the lowpoly to the selection.
Then Bake with "Selected to active".

You are welcome!

[Jorzi]

EDIT: Selected to active is the way to go, like I describe below
Actually, the hipoly doesn't need to be made from the lowpoly at all (although I usually do it just to get the shape right) nor does it need to be unwrapped. This means that you can make the hipoly with little attention to polycount or topology as long as it has approximately the same shape and shares the same spatial coordinates as the lowpoly.

Also a thing to note is that, at least in blender 2.49, the approximate AO, while faster, is also buggier and crashes often when baking (always save your model before baking, as blender often spontaneously crashes when you press the bake-button)

I usually bake raytraced ao with 8-12 samples giving a slightly grainy look which, I think, suits the textures nicely. I usually also just check the normalized-button to get the brightest barts white and the darkest parts black. Skycolor AO can be a nice thing to experiment with, giving nice lighting especially to buildings, although I usually just bake a simple normalized black&white AO for use when painting the base textures.

[Remotehorst]

Good to know. Thank you Jorzi!

Can you tell me if you use Adaptive QMC when using Raytrace?
And what about the Falloff? Do you also use it for the models you make?

Im currently baking AO for a baseplate

Edit: Since years now my approximate bakings never crashed.

[Jorzi]

What I've read, adaptive qmc sampling is most efficient for stuff like soft raytraced shadows. For raytraced ao, on the other hand, constant qmc is generally faster. Jittered is the old sampling method, gives higher quality per sample but takes more time.

I generally don't use falloff, since I want to do a shadow simulation. Falloff is best when you want to accentuate the recesses on your model and it gives nice artistic freedom, but it is less suitable for doing a general shading on models.

About the baking causing crashes, maybe it's because of my amd processor or something....

[macuser]

well i did the bake like you said and it turned out nice..... BUT i have these horrible defects on my bake can you tell what went wrong?

[Remotehorst]

I think that these faces on the uv map are overlayed by other faces. Maybe. Im not sure

[macuser]

Well I'm not sure what you mean by "overlayed" however the lowpoly model does not have any faces on top over there. with the highpoly the same is true BUT when i baked it i have the lowpoly and highpoly occupying the same space (as directed on blender.com) if that is part of the problem i may just have to adjust the bias a little i'll try that