Member ID Guy Posted April 3, 2009 Member Report Share Posted April 3, 2009 Hey everyone I am having a bit of trouble here as I am new to the whole retopolgy thing. Here is my situation. I have an obj mesh that is from a 3d scan so its detailed and has a lot of triangles. I opened in 3d coat as a reference mesh then built a new low res mesh using the re topology tools over it. Now the question is how do I get a displacement map from the larger mesh so that I can open my low poly mesh in cinema 4d and render with displacment. I have tried using the bake texture tools within the retopolgy dropdown, but I think I am doing something wrong with the UV's. Is there a way to avoid manually painting the uv seams on my new low poly mesh and have 3d coat just auto generate them and bake the displacement map onto them from the scan mesh? Sorry if these seem like basic questions, but like I said this is sort of a new area for me, and I have read the manual, but am still stumped. Quote Link to comment Share on other sites More sharing options...
Andrew Shpagin Posted April 4, 2009 Report Share Posted April 4, 2009 The easiest workflow is: - make retopology - Retopo menu->Merge in scene, choose auto mapping More advanced and of course accurate: - Go to "Mark seams" Mark seams - Unwrap - Retopo menu->Merge in scene, choose Keep UV Quote Link to comment Share on other sites More sharing options...
Javis Posted April 4, 2009 Report Share Posted April 4, 2009 Does this also keep symmetry? Quote Link to comment Share on other sites More sharing options...
Member ID Guy Posted April 4, 2009 Author Member Report Share Posted April 4, 2009 The easiest workflow is:- make retopology - Retopo menu->Merge in scene, choose auto mapping More advanced and of course accurate: - Go to "Mark seams" Mark seams - Unwrap - Retopo menu->Merge in scene, choose Keep UV Thanks andrew this helps some, but I guess I am stumped on the best workflow for the end result I am aiming for which is take a highpoly mesh from 3dscan data and reconstruct a low poly over it then get a displacemnt map from the high poly back onto the low poly in my 3d app which happens to be Cinema 4d. Here is what I am doing so far. 1. File Import scan mesh model .obj I leave smooth object checked, and under UV I tell it to keep the UV's and no smothing of the UV since the scanning software gave it UV seams when it exported out the .obj Granted they are messy UV seams since it is a high poly triangle mesh. Also should I unwrap the uv mesh for the imported scan data? Does this matter in the end when I try to bake my displacement onto my retopo mesh? 2. Click on the retopology tool and manually build the quad mesh around it. 3. I then marked the seams and edges and unwrapped. This was part of my earlier question is there a way to automate it, but you answered that. 4. Then click Bake texture at the bottom of the Retopo commands tool. I left all settings at default and told it where to save the displacement map. 5. Now is where I get a little more confused. How to get the low res retopo mesh out to C4D with the uv map so I can apply displacement textre there. I end up clicking export raw object as .obj 6. I open the .obj in cinema and put a smoothing modifier on it (hypernurbs as cinema calls it) I then put the displacement map into the displacement channel and render. It looks ok in some areas except around where the UV seams are. There is noticeable distortion at the seams for some reason and they are in the shape of the quads on the low res retopo mesh. I saw the video tutorial that was posted on taking a low poly with uv's applied in C4d painting and texturing in 3d coat then going back to c4d, but it does not really help with what I am trying to do which is take a large mesh with a lot of detail from a 3d scan and bake the texture onto a low res mesh somehow. Any tips would be appreciated. Step by step on the correct import, baking and export options would be helpful if you have time. I really like the retopo tools in 3d coat. Its very simple in straightforward to get a low res mesh built, but getting the displacement texture from the reference model to properly show up on the retopo model in your other 3d app is not as clear. Looking forward to buying 3.0 when it is ready for full release! Quote Link to comment Share on other sites More sharing options...
Andrew Shpagin Posted April 5, 2009 Report Share Posted April 5, 2009 I can offer you more easy and fast workflow 1) Import scan data as reference mesh (it works much faster) 2) Perform retopo 3) Mark seams and unwrap if need 4) Retopo menu->Merge into scene (Choose Keep UV or automapping in dependence on have you unwrapped before or no) 5) Export low poly mesh (Choose original positions in export dialog) and displacement map from the same dialog Quote Link to comment Share on other sites More sharing options...
Member ID Guy Posted April 5, 2009 Author Member Report Share Posted April 5, 2009 I can offer you more easy and fast workflow1) Import scan data as reference mesh (it works much faster) 2) Perform retopo 3) Mark seams and unwrap if need 4) Retopo menu->Merge into scene (Choose Keep UV or automapping in dependence on have you unwrapped before or no) 5) Export low poly mesh (Choose original positions in export dialog) and displacement map from the same dialog Awesome that is exactly what I was hoping to hear. I knew I was doing something wrong. I will give that a shot. Quote Link to comment Share on other sites More sharing options...
Member ID Guy Posted April 6, 2009 Author Member Report Share Posted April 6, 2009 I can offer you more easy and fast workflow1) Import scan data as reference mesh (it works much faster) 2) Perform retopo 3) Mark seams and unwrap if need 4) Retopo menu->Merge into scene (Choose Keep UV or automapping in dependence on have you unwrapped before or no) 5) Export low poly mesh (Choose original positions in export dialog) and displacement map from the same dialog Ok I tried your steps, but when it tries to merge into scene it takes a few minutes on a quad core system then a mesh pops up that looks like my model has exploded with polygons all over the place. If I subdivided the retopo mesh x4 it merged it in fairly clean, but it had lots of polygons which defeats the point of retopo right? I tried to file/export low poly mesh just to see, but there is no option to save displacment from this dialogue. See my attached image. I was able to get the result I was looking for by these steps. 1. Import reference mesh 2. Open topology tools and reload the saved retopo mesh I had started from just using the standard import .obj as my object to build retopo over. You are right the file is much lighter and faster now this way. 3. I marked seams and unwrapped manually in the retopo dropdown. 4. I used the bake texture from the retopo dropdown and kept default settings with only displacement map as output. 5. I then used export raw object from the retopo dropdown and saved as .obj 6. I opened the obj in C4D and applied a hypernurbs to smooth the low poly mesh that had the same polgons as my 3dcoat retopo mesh, and then put the displacement map that 3dcoat output into the material channel and it rendered great for the most part. I think I had some sharp corners on my retopo that were causing the displacement to get funky, but that is my fault. I will post some images and the 3dcoat file tonight to make it more clear what happened with my experiments and see if you can offer suggestions. I did get the end result I was going for, but would still like to hear from you if I went the best route to get there. Also this got me displacement which I was looking for, but what if I want a color texture from the reference mesh baked on also. I could not figure out a way to open up a reference mesh as an obj that has a .mtl file in 3d coat and have the texture show up. I can by just doing a regular import of an .obj then using the load texture command, but then I am back to using a heavy mesh for my displacment. On the dinasour looking thing you made the retopo tutorial from how did you get the texture to show up on your reference mesh? Quote Link to comment Share on other sites More sharing options...
Andrew Shpagin Posted April 7, 2009 Report Share Posted April 7, 2009 Seems you found right way. Also this got me displacement which I was looking for, but what if I want a color texture from the reference mesh baked on also. I could not figure out a way to open up a reference mesh as an obj that has a .mtl file in 3d coat and have the texture show up. I can by just doing a regular import of an .obj then using the load texture command, but then I am back to using a heavy mesh for my displacment. On the dinasour looking thing you made the retopo tutorial from how did you get the texture to show up on your reference mesh? If mtl file contains path to texture 3D-Coat will open texture as well and it will take part in baking process. Please show your mtl file and I will point what is wrong. Using ref mesh with texture is usual workflow. I know that peoples use it. Quote Link to comment Share on other sites More sharing options...
Member ID Guy Posted April 7, 2009 Author Member Report Share Posted April 7, 2009 Seems you found right way.If mtl file contains path to texture 3D-Coat will open texture as well and it will take part in baking process. Please show your mtl file and I will point what is wrong. Using ref mesh with texture is usual workflow. I know that peoples use it. Attached is the .mtl file. Just to make sure I opened the model using the standard import model command then loaded the texture and it shows up on the model in the viewport. I then exported that out with the color as obj. Then I did file import reference mesh and it shows up in the viewport with no texture applied. I even tried to load texture on the reference mesh and nothing shows up. mtl_file.zip Quote Link to comment Share on other sites More sharing options...
Andrew Shpagin Posted April 7, 2009 Report Share Posted April 7, 2009 Attached is the .mtl file. Just to make sure I opened the model using the standard import model command then loaded the texture and it shows up on the model in the viewport. I then exported that out with the color as obj. Then I did file import reference mesh and it shows up in the viewport with no texture applied. I even tried to load texture on the reference mesh and nothing shows up. Try to replace map_Kd C:\Document.....t_color.tga on map_Kd "C:\Document.....t_color.tga" Quote Link to comment Share on other sites More sharing options...
Member ID Guy Posted April 7, 2009 Author Member Report Share Posted April 7, 2009 Try to replace map_Kd C:\Document.....t_color.tga on map_Kd "C:\Document.....t_color.tga" Im not sure I follow you. I made sure the path is pointing to the correct location if that is what you mean? Still doesn't import with the texture showing in both reference geometry or regular import. I downloaded a free model off the web, and it opens fine with the texture showing so its something to do with the file. I dont understand though because the obj and mtl file was created right out of 3d coat with the texture applied. I noticed on the model I downloaded there was no network path to the texture, just the name of the texture, but it still worked. I will try it with a new model tonight from the beginning and see what happens. Quote Link to comment Share on other sites More sharing options...
Andrew Shpagin Posted April 8, 2009 Report Share Posted April 8, 2009 Im not sure I follow you. I made sure the path is pointing to the correct location if that is what you mean? Still doesn't import with the texture showing in both reference geometry or regular import. I downloaded a free model off the web, and it opens fine with the texture showing so its something to do with the file. I dont understand though because the obj and mtl file was created right out of 3d coat with the texture applied. I noticed on the model I downloaded there was no network path to the texture, just the name of the texture, but it still worked. I will try it with a new model tonight from the beginning and see what happens. The main problem is in spaces in path to texture. Try to place object and texture to some place without spaces. Quote Link to comment Share on other sites More sharing options...
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