Aquila Kytori

If in doubt use the official SL viewer I uploaded your .dae file and used the high lod mesh for Physics and then Analyzed the physics mesh. When rezzed I set the Physics shape Type to prim. Surprisingly the physics seemed to be working fine ! The number one problem I found was that it was being uploaded as a linkset of 20 objects. I coloured each one a different colour for you to see better : and an exploded view : I suggest you find out why this "single " object is getting split into 20 objects when you export as Collada and fix that. You are not the first person to have this happen when using sketchup and not going to like this but ........ I suggest you learn a little Blender :smileysurprised: I'm going to try opening your .dae in Blender to see how it looks there ............

WhiteRock Darkstone wrote: Aquila, it's one single mesh. Do you think I should make it into two separate ones? Maybe I should make the roof a separate mesh? No. I think you should post your Sketchup and or .dae file so that we can take alook at it

Hi When creating, uploading and assigning a physics mesh for a model that needs accurate collision surfaces there are a couple of basic rules that have to be complied with. Can you confirm that you have followed Rule 1? Rule 1 : Each visual mesh object has to have its own physics mesh. When rezzed in world is your mesh building a single mesh object or a linkset of 2 or more separate objects ?

Drongle wrote Also, when you have multiple materials, the UV mapping of each can ovelap. They don't interfere because each becomes a "face" in SL, with a different texture applied. So the UV map of each material can fill the whole UV unit square. That means you can have more texture pixels per unit of surface area, improving the texture resolution over what you can achieve if you cram all the surface into one UV map. Just to try and illustrate what Drongle said: and next with each material using the full UV space:

Hi I am not a Maya user but as you seem a bit desperate (2 posts asking the same question ) and untill a Maya user comes along ............. I think you need to use the Maya FBX Converter which you can download from here, http://usa.autodesk.com/adsk/servlet/pc/item?siteID=123112&id=22694909 And check out this youtube video on how to use it , Edited to add: I also seem to remember something about "Freezing Transformations" and or "Deleting History" before exporting. If that makes sence to you then try that ..............can't find the forum posts which mentions those

What Drongle is describing only happens if the the Uploader is creating the “secret” additional materials and the origin of the mesh is outside the bounding box. Edit after reading Drongles explanation: OOOOps, Edited again: From Drongles explanation, the offset physics would be less noticeable if you moved the origin to the center of the bounding box. Move it up a little in the Z axis.

This is what happens when I create a cube in Blender and subdivide it so that it has 24,500 vertices (no materials assigned).Then in edit mode move the cube away from its origin. This is how it appears in the Uploader (using the official SL viewer) with a simple cube used for Physics: and when rezzed inworld: If before exporting I Set Origin to Geometry at step 4 (first image) then the cube (and Physics) work as expected. Repeating steps 1 to 6 for a cube which has only been subdevided 5 times (6,146 vertices) then it uploads as expected

Hi Chic You could check the Bounding Box opton in Blender then compare it with the the bounding box when rezzed inworld with Develop > Render Metadata > Bounding Boxes enabled.

yes probably. But there are a couple of rules you need to comply with 1: If your mesh is a single mesh object then the Physics mesh must also be a single mesh object. (and visa versa). 2: The bounding box of your physics mesh has to be the same size (in the X, Y And Z axis) as the bounding box of the visual mesh. 3: Avoid any small or thin triangles in the Physics mesh. You don't need alot of details in the physics mesh , just enough collision surfaces for the avatar to collide with. Stairs can be a ramp. Windows can be filled in etc. Export your Physics mesh as a separate .dae file When uploading your skybox open the Physics tab of the mesh Uploader and in Step 1 choose the From File option and upload the physics .dae file there. Don't touch anything else in the Physics tab. Calculate weights and fees as usual then when you have your skybox rezzed inworld edit it. In Edit panel open the Features tab. There change the Physics Shape Type option from the default Convex Hull to Prim. Now you should be able to walk around inside the skybox.

Hi Where to start ………………….? As this is your very first building I would suggest a basic workflow something like: 1: Create you mesh building 2: Optimize the mesh for real time rendering, that means removing any of the vertices that are not actually contributing to the shape of the mesh. 3: Decide how you want to texture it, using baked textures, a combination of baked and textures created in a 2D editor, or will it be using seamless tillable textures that will be added in world. Then UV unwrap the mesh accordingly. 4: Create a physics mesh. Without a physics mesh you will not be able to walk around inside your building. This should be a simplified version of the visual mesh. When you have the High LOD (visual) mesh and the Physics mesh completed you are ready to export them in .dae (Collada) format and upload both to the mesh uploader. Rez in world, set the Physics shape type to Prim and slap on your texture. Sounds simple, what can go wrong …….. ? A lot. :smileysurprised: Linden Lab provides a parallel grid that can be used for testing your mesh creations before final upload to the main grid. Uploads are free on this Beta test grid. I suggest you take advantage of this. On second thoughts don’t even bother with the Optimization of your building at this stage. For the moment just aim to get it so you walk around inside. Later you can work on reducing the LI costs. Just as later you can work on creating your own lower LOD meshes. :smileyhappy: Most important is to start uploading and testing. Then like everyone else you will hit problems and one by one you will learn how to overcome them. See this post from an earlier forum thread on how to get into the Test grid: https://community.secondlife.com/t5/Mesh/Mesh-tricks-for-low-LI/m-p/3084592#M35547 Message number 11. If it was my very first building, I wouldn't even be bothering about UV unwrapping and texturing at all. I would be to impatient to see how it looks rezzed inworld ...................

Rhiannon Arkin wrote: I was reading that there are mesh sandboxes to upload for free for testing purposes? How would I find those? Me > Preferences > Advanced > and enable the option Show Grid Selection at Login :  When Logging in choose the Second Life Beta Test Grid and then login to Morris:  There are other sandboxes on the Beta grid but I suggest Morris as your first destination because I find it the most reliable. The sand box there is not flat or full sim size. If you need more space then open the main map and search for Mesh Sandbox. The beta Grid is like a little separate parallel world to SL used for testing. Any L$'s you are charged there for uploading will not be deducted from your main SL account. Before you can Upload mesh on the Beta grid you will probably be asked to re-do the little Mesh upload test.

Drongle, the starting point each time I scaled was this one from the earlier post : Aquila Kytori wrote: Lastly I added a plane in top view, then in: Edit mode, rotated it about the x axis 90° Front view, G X 1 followed by G Z 1, so that one corner of the plane was at x0 y0 z0. Ran the script and got the following : and can also confirm you are perfectly correct, no deviation what so ever when moving a vertices 0.25, 0.5 or 0.75 along the x axis.

Hi Drongle Drongle McMahon wrote: That was all probably rubbish. :matte-motes-sick: And unfortunately all way above my head. Now I understand that number to be the computer language equivalent of being as close to being zero without actually being zero. Could make a good password for my online bank account. Drongle McMahon wrote: What happens if you scale the plane up by 100? Does the funny number scale up too?  Shouldn't the -99.00 be -100.0 and the 101.0 be 100.0 ?  That did change the number to ................e-06 and finally: 

I was curious about what you meant about not using modifiers because of “vertex drift” so found a little script here : http://blender.stackexchange.com/questions/1311/how-can-i-get-vertex-positions-from-a-mesh that prints out vertex x y and z positions of meshes in Blender. I began by: in top view adding a plane and then in edit mode running the script : Then moving one of the vertices along the x axis by 0.1 : Accurate to 7 decimal places, I repeated for moving 0.2, 0.3, 0.4, 0.5 etc up to 1.0 along x axis. The 0.5 was exactly 0.5 in the print out but all the rest had a similar deviation as the first. Was this the kind of “drift" that you were referring to ? If so does the collada exporter export to 7 or 8 decimal places ? surely not . Next I cut my plane in half and added a mirror modifier and after applying it ran the script. All the vertices showed no deviation. Lastly I added a plane in top view, then in: Edit mode, rotated it about the x axis 90° Front view, G X 1 followed by G Z 1, so that one corner of the plane was at x0 y0 z0. Ran the script and got the following : 5.960464477539063e-08 :smileysurprised: How can that even approximate zero ? What does this number mean ??? When I Googled for it I found some results that were Blender related but I couldn’t understand them. Also other none Blender related results ! ! How can such an apparently crazy number (to me anyways ) get so many results from Google ? Hoping you , Drongle or some one else with a maths brain can explain it to me. Last thing I did was move that corner vertice along the x axis 0.1m:

uuuuuuuuuuumm................ would the clue to the answer be found in the quote below ? : ChinRey wrote: Edit: Maybe I should illustrate what I mean with ALIGNING precisely: Just a guess, could it be that maybe, perhaps or be that possibly the first has faces aligned exactly to X or Y and Z axis ?

I hadn't thought of only using 3 triangles to represent each stack and felt sure using the version where the tris are joined at the pointy end would make a noticeable difference compared to the Lowest Lod that I had been using. Unfortunately not Note: Triangle and vertex count are those given in the Uploader and both LOD0a and LOD0d are smooth shaded.  If I really needed to reduce the download cost more then I would have to experiment with using less geometry in the other Lod meshes. Using the "2 triangle" example (like the "2 plane" version in the image above, LOD0b) would really mean using 4 because of the need to duplicate and flip the normals so that the texture could be seen from all angles.

Showing what is possible when using hand made lower Lod models is good but if you really want to encourage people new to mesh to do the same then it would be even better to include the wire frames. At the moment i’m putting together a sim size speedway stadium where most of the objects are very large so I only have to worry about the Medium Lod model for most of the parts. But today I needed some sets of tyre stacks to protect the ends of the walls that separate the race track from the pit lanes:  ( and the download weight was again the magical 1.2 The Med and Low were having some effect on the LI cost but by far the biggest effect for an model this size, (3 x 2 x 1.5m) was the Lowest lod model ). If you follow the workflow of : Create high Lod mesh. Uv Unwrap. Create texture. Create lower Lod mesh models (in a way that the lower Lods can use the same UV/texture without additional editing ) then from the above example you can see that often, making the lower Lods is very little extra work . If you are posting images of the end result please consider also adding wireframes of how you got there. A method to remove edge loops without destrying UV's see message number 8 here : https://community.secondlife.com/t5/Mesh/Any-advice-on-ways-to-line-up-UV-islands-for-the-different-LODs/m-p/2936244#M31636

Chic Aeon wrote: ..................perfection. This exercise IS supposed to be FUN . Mesh, exercise, fun and cute :

Hi Chic Have you tried adjusting the colour options in Preferences ? For 3D Viewport background colour see image below :  Just to add : the latest Blender with lots of bug fixes is 2.78a



.............. SNAP ! :smileyvery-happy:

Hi Could be this old one : https://community.secondlife.com/t5/Mesh/Making-physics-HELP/m-p/1751867#M18005 Try going back into Blender and editing your Physics mesh so that all the vertices on one side of the physics wall are perfectly on the same plane : Select the vertices of one side and scale them to 0 (zero) in the X or the Y axis, which ever is appropriate. Repeat for the vertices that make up the other side of the Physics wall. Then export as usual.

Hi Bitsy Buccaneer wrote: All of that blank space sends horrors of texture inefficiency up my spine however. But does that still matter if I use a 256 seamless repeated texture instead of a fancy baked shadows one? In this case ...No it doesn’t matter. The UV map layout is not a texture. It is a list of X, Y ( U V ) co-ordinates in the Collada file of your mesh. If you are planning to use a seamless texture on the mesh in world and adjusting the horizontal and vertical repeats then leaving all that space is not being inefficient with your texturing. Using repeating seamless textures like that is probably the most efficient way of texturing things in SL. As far as texture efficiency is concerned, for seamless repeating textures applied in world, using UV map 1 or UV map 2 makes no difference. See Image below :  But………. The texture will not be seamless ! If you look carefully on the mesh that uses UV map 1 or UV map 2 you will notice a vertical seam. To make it “seamless” you would need to straighten out at least the left and right hand edges of the UV island and then scale it in the X axis with UVs > Constrain to Image Bounds enabled so that those edges are perfectly aligned to the edges of the UV space. In UV map 3 I used the Blender UV mapping option Follow Active Quads then scaled it with Constrain to Image Bounds enabled in Blenders UV image editor. Unwrap using Follow Active Quads . (1 method) In Face select mode : Select one quad of your mesh , U > Reset Select the rest of the mesh L Unwrap U > Follow Active Quads UV Editor : UVs > Constrain to Image Bounds Then you need to scale the UV island so that it fills the UV space completely. Note when doing this I unwrapped the end faces separately and scaled to suit. Depending on the texture you are using the seam may hardly be noticable, in which case using your original UV map will be ok

Using the SL viewer : Preferences > Advanced > UI size. The more you slide it to the right the bigger all the popups (and the texts inside them) will be. 

Just a note: If you use the planes method and follow the simple rules about bounding box size, avoiding small or thin tris/planes in the physics mesh, making sure that each visual mesh object has its own physics mesh object and not touching the Analyze or any other buttons in the physics tab of the mesh Uploader, then using the plane method throughout your build works fine. The advantages of the planes method is that you get EXACTLY the collision surfaces you created in your Physics mesh model and also that the physics cost will generally be lower than had you used the box method and Analyzed it. If you start trying to mix the two in the same mesh object then .......... well don't. To do that successfully you would need to divide up the visual mesh into smaller separate objects and upload each separately along with its own physics model , analyzed or not Analyzed.