# Decimating a Mesh

Point Cloud Utils supports mesh decimation using the Quadric Edge Collapse algorithm.

```
import numpy as np
import point_cloud_utils as pcu
v, f = pcu.load_mesh_vf("bunny.ply")
# v_quarter, f_quarter are the mesh vertices and faces of the decimated mesh
# corr_qv and corr_qf are the correspondences between vertices and faces in the
# original mesh and the decimated mesh.
# i.e. corr_qv[i] is the index of the vertex in v which generated v_quarter[i]
# corr_qf[i] is the index of the face in f which generated f_quarter[i]
v_quarter, f_quarter, corr_qv, corr_qf = pcu.decimate_triangle_mesh(v, f, max_faces=f.shape[0]//4)
v_eighth, f_eighth, _, _ = pcu.decimate_triangle_mesh(v, f, max_faces=f.shape[0]//8)
```

**From Left to Right:**full mesh, a quarter of the number of faces, an eighth the number of faces.