Burst Posted August 2, 2015 Share Posted August 2, 2015 Hi there ! I wanted to know if there was a way to bake out geometry and lighting in UV space in a similar fashion to the Projection Modifier in 3DS Max. Here's an example: https://area.autodesk.com/louis_tutorials/export_and_import_the_projection_cage One of my coworkers uses that method to bake out vines growing on a tree. The result is a sequence of baked out UVs with the vines properly placed on the tree's UV space. I'm using a Ray SOP to stick the growing vines on the tree, then in a Mantra ROP I plan to use the UV Render object to bake out the tree's UV. My only worry is how would I get the vines to render out in the tree's UV space ? Hopefully someone has an answer to this otherwise i'll be stuck lighting and texturing in Max Thank you ! Quote Link to comment Share on other sites More sharing options...
davpe Posted August 2, 2015 Share Posted August 2, 2015 hi, I`m not sure what exactly are you trying to achieve, however, rendering to UV space is very simple process in Houdini. On Mantra node you can find an option called UV render object. Here you can specify object to bake out. If you want to bake more than one object you have to either merge them to a single geometry using object merge node, or you have to create more Mantra nodes, each for one object. Output will be geometry color (Cd on points or primitives) if no material is specified on object level, or material with lighting if you assign it on object level. Currently, baking to UV space is not supported with raytracing so you have to switch to Micropolygon engine. Resolution of the output image is specified by a camera defined on Mantra node. hope that helps. D. Quote Link to comment Share on other sites More sharing options...
Burst Posted August 3, 2015 Author Share Posted August 3, 2015 Thanks for the reply. Unfortunately as I stated earlier the UV render object works all fine and dandy for my Tree's UV, but the object "sticking" on the tree's surface just doesn't show where I want to. I've painted a pretty picture to show what I mean. http://d.pr/i/11a42 As you can see the object sticking on the tree, in this case a sphere, just appears like it's "cut out". thank you ! Quote Link to comment Share on other sites More sharing options...
davpe Posted August 3, 2015 Share Posted August 3, 2015 Hi, sorry I haven't read your initial post well enough I guess. unfortunately I'm not sure what result are you trying to achieve. is the problem that the object appears to be cut out or that it is in a different position that it should be? UV render object works just the same way as a regular render does but instead of rendering in a camera space it renders in UV space. object in your picture appears to be cut out because it is casting shadow at the surface below it. Quote Link to comment Share on other sites More sharing options...
Burst Posted August 4, 2015 Author Share Posted August 4, 2015 Hi ! With further experimentation it seems that the Mantra UV render node is quite limited compared to the 3DS Max Projection Modifier. Even when turning the sphere's shadow projection off, it still displays as a cut out because the sphere doesn't have the same UVs as the Tree object. Also, it totally ignores the ligthing at the back and bottom of the tree because it bases itself on the camera view, which isn't what I want. Basically what the modifier does is to Create a cage around the source object (example: A High poly mesh and non-connected accessories). The cage includes the base mesh and all the defined objects that are included in the "volume" of the cage. Then it bakes out the lighting, shadows and colors of the base mesh + whatever is also in the volume, BASED on the UVs of the base mesh. Not only from one camera angle but from EVERY camera angle. Unlike Houdini's UV render. The result is a flattened UV view of the base mesh + objects that can then be transfered to either to a Lower resolution mesh or whatever. Otherwise is there a way for me to have my growing ivy use EXACTLY the same UVs as my tree even though they don't have the same vertices, geometry, volume or anything in common ? I really don't want to be stuck animating in After effects, extruding them or using Volumes. I know it's oddly specific but I'm only asking because if Max can do it, why wouldn't Houdini ? Quote Link to comment Share on other sites More sharing options...
davpe Posted August 4, 2015 Share Posted August 4, 2015 hmm, that's interesting... This 3ds max feature seems to be quite robust plugin. Behaviour with the lighting is really odd though. Never been using this UV render object to actually bake out lighting (just procedural textures) so i haven't noticed. .Anyway, I have done some search and found couple of interesting threads/articles on this topic: http://odforce.net/wiki/doku.php?id=shaderunwrap http://forums.odforce.net/topic/14077-baking-to-texture/ http://forums.odforce.net/topic/22174-how-to-bypass-the-uv-render-raytracing-restriction/ haven't had too much time to explore that but if you read through you will find some sample scenes (which I havent looked at but might be useful). in the first article there is a hint that you should disable "ensure faces point forward" option and untick "Enable Hiding" on mantra node. However, it didn't work for me for some reason. hope it helps and if you find a solution post it here please bcs I would be curious ;-) cheers, D. Quote Link to comment Share on other sites More sharing options...
davpe Posted August 4, 2015 Share Posted August 4, 2015 and the best thing at the end... on Orbolt i have found Texture Baker asset for free it says that it bakes texture and full lighting and its directly from Side fx so it might be working ok (haven't tried though). http://www.orbolt.com/asset/SideFX::texturebaker Quote Link to comment Share on other sites More sharing options...
Burst Posted August 5, 2015 Author Share Posted August 5, 2015 Hi ! After trying out pretty much anything, the texture baker doesn't seem to work... At all. I get a bunch of python errors and it never bakes out anything to my HIP directory. So at this point I'm pretty saying f*** it. I've read somewhere that VDBs can inherit the UVs of the second output, so that's a good way for me to fuse the meshes, and for the baked out UV's i'll try and make myself some Camera rig so i can arrange everything in comp. Thanks for all the help ! Quote Link to comment Share on other sites More sharing options...
davpe Posted August 5, 2015 Share Posted August 5, 2015 Hi, that's a real pity. I guess that texture baker from Orbolt works only in H12 and 13 and haven't been updated for H14 so maybe was a problem. I have seen some pretty cool custom made baking tools so its definitely possible to do in Houdini but it requires some initial manual setup and quite a bit of technical knowledge. Anyway, good luck ;-) Quote Link to comment Share on other sites More sharing options...
Atom Posted August 5, 2015 Share Posted August 5, 2015 After taking a look under the hood at the HDA scripts it seems to be geared to Windows pathing. There are some replace statements on the path that might be messing it up on OSX. I am testing on OSX. Also the default settings of 1024x1024 violate the Apprentice size limit of what you can get out of the COP network which is somewhere around 768x528...close. It may work for Windows users on Apprentice if you lower the setting to something like 512x512 or lower. It is too bad it does not work, baking out of Houdini would be nice. Blender has this feature was well if you are looking for a free baking solution. Quote Link to comment Share on other sites More sharing options...
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