Toolkit 2 - Maya: Displacement Maps

  Displacement Maps  

Displacement Maps - Works in a white to black gradient, pulling surfaces in and out. Black is where the geometry will be pulled in, white will bring it out. Grey means no change will happen.

 Vector Maps  - Works in 3 channels, X,Y and Z.These channels brings the surface displacement out an contains a blend of normal.

 In Mudbox: To generate a displacement map, go into Maps, Extract Texture Map and select Displacement map.

  In the options, we bring the lowest res model into the target models channel, and the highest into the source models. You can change the models by click on them and choosing the one desired.

  For the methods, we need to use ray casting as this will find the highest and lowest points. In the search distance, selecting best guess will help capture the whole image. 

  When creating the Displacement maps, in the options we need to make the image 4096 (4K) to allow the best quality. Following this, place level change as the highest point, and save as a EXR (32) floating point file. Then  wait for completion, turning off the bump map so to be able to export correctly. 

  To export for Maya, click on the geometry and use PG Down button to get to the lowest polygon level (base mesh). Extract and save as a .obj file.  

  * When importing from Mudbox to Maya, Mudbox works 10x bigger. So, you will have to zoom out quite a lot see the object in the Maya view port*

 Once imported, select the geometry and under the shape node in the Arnold tab, use subdivisions, CatClark, creating a Iteration of 2. Work up slowly in the Iterations, taking renders to make sure the smoothing is working correctly with the maps. 

 Create a new aiStandardSurface Material for the geometry.

   Under the Hyper shade, select the shade material node and the aiStandardSurface2SG, creating a importing image file in the Displacement Mat channel. 

 * The node editor will create a displacement node. When creating a first render, it will make a TX. file for Maya to read*

  The map may not read well, this is due to the size difference between Maya and Mudbox. ,Under the Displacement attributes shape node, change the height to 10 (making the map 10x bigger). We want to avoid tearing in the maps. 

  Finally increase the Iteration in the sub visions to the highest point (in this case 6).

Final Render

Vector Maps

 In the likes of the toadstool model, displacement maps wont able to cope with the  high degree of change and undercuts, This is where Vector maps will work better. 

  As with the previous map, chose vector map instead of displacement when creating. Change the size to 4096 (4K), vector space to object, the hi and low res model boxes would have already been pre-filled. When saving the file, place the degree of change in the title (0-6), and finally click yes to adding a .VDM notation when promoted.

Bring the model down to the base mesh, and export into Maya. When in Maya, add a new aiStandardSurface material to the geometry.

 Leave the Iteration at the lowest point, and under the hyper shade go back into the shading node. As you would with the displacement map, at a image pathway in the displacement mat box. 

  In the node editor delete away the place2dtexture node and file1. Then using the checker on the Vector Displacement channel (shading node), add a image file pathway. 

      *Maya will create a vector file node in place of the displacement node*

  Change the iteration to the highest point to allow the vector map to work. I did not have the texture map that came with the toadstool, so its stayed like this.