Modeling Issues [RESOLVED] [ONGOING RESEARCH]

[JohnathanMacBride]

here is the context of my issues:

 

I made the model in Sketchup and Exported it to Collada(*.dae)

I imported it into Blender and began the process of Simplifying, UV Unwrapping and Baking of the Ambient Occlusion Maps.

The issues are two fold. First, I have no idea what the heck this issue is with the faces:

It seems that theres some overlap or something, but I am not knowlegeable enough to know.

Second, My AO Bake is splotchy and terrible. I don't know what I am doing wrong. I have followed the tutorial at Kats Bits

and this is what I get:

Any insight would be greatly appreciated.

[Dora Gustafson]

You may increase the number of samples for the AO mapping:

This way you can make the result less grainy at the cost of a longer processing time
You can not expect too high quality with the UV map you have, each element has very few pixels even in a 1024x1024 map
Somehow you need another UV mapping or more UV maps to improve the result

[Drongle McMahon]

Sketchup does seem to make very bad geometry and UV maps. The phenomena you show might be due to duplicate faces, or face where one overlaps the other for some of their area(s). This can result in stippled shading and in black patches on the ao bake. I suggest you put the 3D view into non-see-through mode select individual faces and delete them to see what's underneath. If you find overlaps this way, you will have to repair the geometry. 

If bearable, I would recommend not using sketchup for anything but a mock-up. Better build from scratch in Blender, after importing trhe sketchup model as a guide if you find that useful. If you know how to refine the geometry, assign materials and UV map in Blender, you must already be not far away from being able to do that.

[JohnathanMacBride]

Thank you so much. I adjusted the samples, yes at a cost to render time, and there were still a few spots that were lacking. I am going to take a guess that there is still something I am not doing right. What did you mean by Another or More UV mappings? 

Also, I will be sure to use Sketchup for mockups only. I have found that modeling in blender takes some getting used to, hence my use of Sketchup. I will try this and let you know what my result is.

[JohnathanMacBride]

I was able to find a plugin for Blender called MeshLint that analyzes and removes unnecessary geometry and faces and such. I ran that and re-ran the AO Bake, results were much better.

My next Conquest is going to be physics. Apparently Blender Doesnt Currently Support exporting Physics Data with Collada Files.

 

Found a solution using Unity 3D. I will report my findings once I have tried it. Thank you both again.

[Drongle McMahon]

Mesh Lint sounds good. As for physics - SL doesn't use the physics stuff in collada, or physics from Blender etc. All it does is make a collision shape which is generated from a normal mesh. By default, it will make the convex hull of the low LOD mesh and use that. For something better (essential for buildings if you want to go inside) you can specify a custom physics mesh on the physics tab of the uploader. (You can use one of the LOD meshes instead, but that usually isn't satisfactory for buildings.) There are two types of shape you can use, the mesh itself (triangle-based shape) or a collection of convex hulls generated by using the "Analyze" button. In both cases, the main thing is to keep the shape as simple as possible to limit physics weight and LI. Avoid curved shapes where possible. For triangle-based shapes, avoid all small/narrow triangles, such as those along the edges of walls with some thickness, which increase weight hugely. Just delete those faces. For "Analyze", it's easiest if you use a shape made up of non-overlapping simple boxes, each of which becomes one hull. Otherwise, the hull generator has a hard time avoiding filling in of spaces you want unobstructed. In either case, you need to set the phsyics shape type to "Prim" inworld to use the shape. If your model has multiple mesh objects, then the physics mesh file must contain a mesh object for each, and they must be in the same order. Each physics mesh (even if there is just one) will be stretched or squeezed to fit into the bounding box of the corresponding high LOD mesh. So they need to fill up that space to avoid distortion. There are lots of threads discussing physics shapes in this forum.

[Scooter Hollow]

With Sketchup, one thing I do is use an obj exporter (I believe it's this one: http://sketchucation.com/forums/viewtopic.php?f=323&t=33448 , been a while since I grabbed it though). The obj files seem much cleaner when moved to blender. If I do use collada, the biggest problem is usually that I have to do a Remove Doubles on things.

[JohnathanMacBride]

So perhaps an OBJ export then Export from Blender to Collada? I think I can do that.