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kettle_uber / Kettle_Bake

Kettle Bake

The Kettle Bake lens shader was designed to bake data lighting information on an object to a texture. It integrates well with Softimage's rendering workflow, but does have some very specific requirements, so be sure to follow the usage instructions closely.

kettlebake_walkthrough_shader.jpg

Options

Input ObjectThe object you want to bake. The ‘Pick’ button launches a pick session. Make sure it has a set of nice non-overlapping UVs for best results.
Normal OffsetThe distance from the surface from which the lighting is sampled. If you find yourself with gaps in your baked image, adjusting this may fix some intersection-based issues.
Grid SizeHow many chunks squared the uv space is divided up into when looking up triangles to rasterize. Default value is pretty good, but larger numbers may speed it up.

Usage

Baking a texture using the Kettle Bake lens shaders works largely like rendering any other image in Arnold from the render manager. Your image file type, output directory and render quality settings all apply as usual. We assume you know how to render an image with Arnold - the following is a walkthrough on the specific requirements when using Kettle Bake only.

Target Object

  1. Ensure the object has unique, non-overlapping UV’s.
  2. Freeze the object’s transforms.
  3. Smooth your object (at least one level of subdivision is required).

Camera

  1. Create a camera. Delete the root and interest, you don’t need them.
  2. Freeze the camera’s transforms.
  3. In the camera properties, set the picture ratio and pixel ratio to 1.
  4. In the render tree, right click on the camera node while hovering over ‘Lens Shaders’ and click ‘Add Item’ to expose a port. Plug in a Kettle Bake camera shader node.

kettlebake_walkthrough_camera.jpg

Shader node

  1. In the Kettle Bake node, pick the object you want to bake, and adjust further parameters as necessary. refer to the table in the Options section above for parameter descriptions.

kettlebake_walkthrough_shader.jpg

Pass

  1. In your render pass, set the camera you just created as the pass camera.
  2. Set the aspect ratio and pixel ratio to 1 to create a square image.
  3. Set your output height/width according to the size of the texture you want to bake. The aspect ratio must be square.

kettlebake_walkthrough_pass.jpg

Arnold Render Options

  1. In the User Options, input “preserve_scene_data 1”, without the quotes.
  2. In the Diagnostic tab, ensure that “Ignore User Options” is not checked on.

kettlebake_walkthrough_aro.jpg

Congratulations!

You can now render your pass as you would normally, and even preview render in viewport when looking through the bake camera.

Updated