[edit] mesh_poly_reduce

[edit] About

Name	Poly Reducer	Version	1.0 - 2006.02.07
Removed polygons from a mesh while maintaining the shape, textures and weights.		License	GPL: GNU General Public License
Menu	Group: Mesh	Blender	2.42 - 2.46
Author	Campbell Barton
Link(s)	Included in Blender

Executable: mesh_poly_reduce.py	Modules:
Data:	External Dependencies: None

Additional information: * Included in Blender 2.42a - 2.46.

[edit] Introduction

[edit] Poly Reducer

Mode: Edit Mode (Mesh)

Menu: Mesh → Scripts → Poly Reducer

[edit] Description

This tool can be used instead of blenders decimator modifier as a way to remove polygons from a mesh while keeping the original shape as much as possible.

Reasons you may want to use a polygon reducer are:

To make 3D Scanned data useable when rendering and editing.
Generate Level Of Detail models (LOD's), for games or simulation models.
To speed up render times.

[edit] Options

Poly Reduce is accessed from editmode and will operate on the entire mesh.

On activation a popup will be appear with the following options.

Poly Reduce: Scale the meshes poly count by this value.
Boundary Weight: Weight boundary verts by this scale. Zero disables boundary weighting.
A boundary vert is a vert that is not completely surrounded by faces. Some meshes have no boundary verts. eg. a cube has no boundary verts where a plane has all boundary verts.
Area Weight: Collapse edges affecting lower area faces first. Zero disables area weighting.
Triangulate: Convert quads to tris before reduction, for more choices of edges to collapse.

The advantage of triangulating is you have a larger set of edges to choose from when collapsing giving a higher quality result.

UV Coords: Interpolate UV Coords (if existing)
Vert Colors: Interpolate Vertex Colors (if existing)
Vert Weights: Interpolate Vertex Weights. (if existing)

[edit] Hints

Poly reducer has some advantages and disadvantages compared to Blenders decimator modifier, here are some pros and cons.

Pros

Higher quality resulting mesh.
Can operate on any mesh, will not throw errors if the mesh has odd face/edge/vert topology.
Options to controle where polygons are removed.
Keeps materials assigned to faces.
Maintains UV Texture coordinates, Vertex colors, and Vertex Group Weights (used for bone weight painting) - This makes it very useful for game/realtime models.

Cons