MATLAB Function Reference |

Reduce the size of patch faces

**Syntax**

shrinkfaces(p,sf) nfv = shrinkfaces(p,sf) nfv = shrinkfaces(fv,sf) shrinkfaces(p), shrinkfaces(fv) nfv = shrinkfaces(f,v,sf) [nf,nv] = shrinkfaces(...)

**Description**

`shrinkfaces(p,sf)`

shrinks the area of the faces in patch `p`

to shrink factor `sf`

. A shrink factor of 0.6 shrinks each face to 60% of its original area. If the patch contains shared vertices, MATLAB creates nonshared vertices before performing the face-area reduction.

`nfv = shrinkfaces(p,sf)`

returns the face and vertex data in the struct `nfv`

, but does not set the `Faces`

and `Vertices`

properties of patch `p`

.

`nfv = shrinkfaces(fv,sf)`

uses the face and vertex data from the struct `fv`

.

`shrinkfaces(p)`

and `shrinkfaces(fv)`

(without specifying a shrink factor) assume a shrink factor of 0.3.

`nfv = shrinkfaces(f,v,sf)`

uses the face and vertex data from the arrays `f`

and `v`

.

`[nf,nv] = shrinkfaces(...)`

returns the face and vertex data in two separate arrays instead of a struct.

**Examples**

This example uses the flow data set, which represents the speed profile of a submerged jet within an infinite tank (type `help`

`flow`

for more information). Two isosurfaces provide a before and after view of the effects of shrinking the face size.

- First
`reducevolume`

samples the flow data at every other point and then`isosurface`

generates the faces and vertices data. - The
`patch`

command accepts the face/vertex struct and draws the first (`p1`

) isosurface. - Use the
`daspect`

,`view`

, and`axis`

commands to set up the view and then add a`title`

. - The
`shrinkfaces`

command modifies the face/vertex data and passes it directly to`patch`

. [x,y,z,v] = flow; [x,y,z,v] = reducevolume(x,y,z,v,2); fv = isosurface(x,y,z,v,-3); p1 = patch(fv); set(p1,'FaceColor','red','EdgeColor',[.5,.5,.5]); daspect([1 1 1]); view(3); axis tight title('Original') figure p2 = patch(shrinkfaces(fv,.3)); set(p2,'FaceColor','red','EdgeColor',[.5,.5,.5]); daspect([1 1 1]); view(3); axis tight title('After Shrinking')

**See Also**

`isosurface`

, `patch`

, `reducevolume`

, `daspect`

, `view`

, `axis`

Volume Visualization for related functions

showplottool | sign |

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