by Benjamin Morrison in Scripts and Addons


Nodegroup Parameters

  • Index : Current index to output.
  • Start Delay : Delay playback / freeze playback until this frame is reached.
  • Index Offset : Offset the current index.
  • X Cells : Total number of horizontal cells.
  • Y Cells : Total number of vertical cells.
  • Adjust Total : Adjust total cell count for uneven cell sheets.
  • Loop Count : Playback limits.

Tutorial: Sprite Planes

  1. Add Menu (SHIFT+ A) > Mesh > Create New Sprite Plane
  2. Select Spritesheet file and choose a host type/Preset:
    • Animated : Index driven by current frame
    • Static : Index driven by random number
    • Particle Animated : Index driven by particle age
    • Particle Static : Index driven by particle index
  3. Setup sheet by either:
    • Running operator: Object > Setup Spritesheet
    • Manually set the group node parameters and run operator: Object > Scale From Sprite Node

Tutorial: Sprite Packing

Sprite packing is performed through the Spritesheet Generator Toolshelf in the UV/Image Editor

  • Generate Spritesheet prompts to user to select sprites for packing and then generates an new sheet from them based on the 'X Cell Count'
  • Regenerate Spritesheet last images used in Generate Spritesheet and repacks based on the 'X Cell Count'
  • Enabling Sheet from Render will generate a spritesheet from animation renders. These sheets can also be used with Regenerate Spritesheet

Tutorial: Atlas to Mesh

  1. Add Menu (SHIFT+ A) > Particle Atlas to Mesh Group
  2. Set creation parameters using the operator properties(Bottom left corner of 3d view)
    • Sheet Path : Atlas for conversion
    • Cells : Set atlas cell values
    • Subdivision : Controls the accuracy of the conversion
    • Dilate Alpha : Grows the alpha of each cell
    • Un-Subdivide : Enable/Disable mesh optimization
    • Decimate Factor : Number of optimization steps
    • Triangulate : Triangulate final meshes
    • Group : Create a new group and add mesh to it
    • Individual Group : Create, and apply, a unique group for each mesh
    • Island Clean : Remove small mesh islands based on their area.
    • Surface Type : Shader type to use for the new objects' material
  3. Experiment with subdivision and alpha dilate values to get a feel for how they affect the mesh generation. Higher subdivision values are very computationally expensive and you should focus on alpha dilation to recover clipped details. Disable Un-Subdivide to better see generation process. Alpha dilation is likely to generate small floating islands that can be cleaned with the Island Clean parameter set to a low value.

Advanced Use / Materials / Manual Setup

The spritehandler node group functions by scaling UV coordinates into ranges appropriate for stepping over grid packed spritesheets/material atlases. Refer to demo files and observe how the handler nodes are being driven by their own sets of uv coordinates and masked where necessary.