This page provides information on texture baking using the V-Ray Baker Tool.
Overview
Rendering to texture, or "texture baking", creates texture maps based on an object's appearance in the rendered scene. The textures are then "baked" into the object that is, they become part of the object via mapping, and can be used to display the textured object rapidly on graphics cards using hardware-accelerated API such as OpenGL and DirectX.
V-Ray BakerTool is V-Ray's solution for texture baking in Houdini. It supports map baking, projection baking, bake to texture tiles and multiple geometries baking. All of these can also be animated.
Node
The V-Ray BakerTool SOP comes with 2 inputs:
- A low poly input used to specify the path to the baked object;
- A high poly input used to specify the source high-res geometry when using Projection baking.
These two inputs are also present as parameter fields on the node itself, in case you specify the path to a SOP node in another network instead of e.g. object merging. You can also specify more than one object when using the parameter fields instead of the node inputs. See the Common Use section below.
Common Use
You could specify more than 1 object when using the parameter fields instead of the node inputs, in which case the evaluation is handled as follows:
Maps Baking Mode
The baking setup is evaluated for every object in the list. For example:
LowRes Meshes: /obj/First /obj/Second /obj/Third
Bake to Texture Tiles is On and uv range is 0:0 , 2:2
This produces 4 renders (one for every Texture tile) for every object in the list. A total of 12.
Project Baking Mode
In Projection Baking mode, with more than one object in either the Low or High Poly lists, one of the following happens:
- For Single Low Poly and Multiple High Poly objects, each high poly object is, one by one, projected over the low poly object. To prevent overwriting of the output files, use the ${CTO} tag in the output file path.
- For Multiple Low Poly and Single High Poly objects, the high poly object is projected over each low poly object, one by one. To prevent overwriting of the output files, use the ${CPO} tag in the output file path.
- For Multiple Low Poly and Multiple High Poly objects, each high poly object is projected over the corresponding low poly object in the low poly list.
*${CPO} - currently processed object
*${CTO} - current target object
Parameters
Bake Now – Starts the baking process.
LowRes Meshes – Specifies the object(s) to be baked.
HighRes Mesh – (Available when Baking Mode is set to Projection Baking) Specifies the high poly mesh.
V-BakerTools parameters are grouped into three main tabs. Find links to each tab below.
Notes
- Preview of the final result is only available for one object.
- Preview of the final result does not work when baking to texture tiles.
- Object paths for the Low and High poly lists should be absolute.
- Currently, there is no automatic support for Metalness workflow.
- Final render must be started from the Execute Baking button in the V-Ray BakerTool's UI when the Low/High poly lists contain more than one object, or when baking to texture tiles.
- When baking trough TOPs, files are saved with gamma 1.
- Height/Displacement map based on distance between Low poly and High poly meshes no supported yet.