Go to: Synopsis. Return value. Keywords. Related. Flags. Python examples.

Synopsis

polyGeoSampler([alphaBlend=string], [averageColor=boolean], [clampAlphaMax=float], [clampAlphaMin=float], [clampRGBMax=[float, float, float]], [clampRGBMin=[float, float, float]], [colorBlend=string], [colorDisplayOption=boolean], [computeShadows=boolean], [displaceGeometry=boolean], [flatShading=boolean], [ignoreDoubleSided=boolean], [lightingOnly=boolean], [reuseShadows=boolean], [sampleByFace=boolean], [scaleFactor=float], [shareUV=boolean], [useLightShadows=boolean])

Note: Strings representing object names and arguments must be separated by commas. This is not depicted in the synopsis.

polyGeoSampler is undoable, NOT queryable, and editable.

This command performs a render sampling of surface color and transparency for each selected vertex or face and stores the sampled data as either the color value, or uses the sampled data to displace the affected vertices or faces by a sampled data value. Transparency is not used for displacement, and displacement is performed along vertex normals. The sampled data value used can be pre-scaled by a user defined amount. Additionally, the normals chosen for sampling can be overridden using a "flat" shading option. This option basically means to always use the normals of the faces when computing sampling values. This may be a desired if the user wishes to override an edge smoothness factor. Basically with the "flat" shading option on, edges are always considered to be hard. Note that displacement sampling will result in the -sampleByFace option to be turned off, since a displacement of a vertex always affects the faces the vertex is connected to. Finally, it is possible to force the storage of shared colors per vertex, and / or force the usage of unshared UV values. The computation of the resulting color is as follows: 
        resulting-RGB = (sampled-RGB * scale-factor);
        if (color blend is none)
                resulting-RGB = geometry-RGB
        else if (color blend is add)
                resulting-RGB = geometry-RGB + sampled-RGB;
        else if (color blend is subtract)
                resulting-RGB = geometry-RGB - sampled-RGB;
        else if (color blend is multiply)
                resulting-RGB = geometry-RGB * sampled-RGB;
        else if (color blend is divide)
                resulting-RGB = geometry-RGB / sampled-RGB;
        else if (color blend is average)
                resulting-RGB = (geometry-RGB * 1/2) + (sampled-RGB * 1/2);
        if (clamp option set)
                clamp resulting-RGB between minimum-RGB and maximum-RGB,
The analogous computation is done for computing the resulting alpha value. The command requires that there be a camera selected in your scene in order to work properly in -batch or -prompt mode.

Return value

booleanSuccess or Failure

Keywords

poly, sampling, GeoSampler

Related

polyColorPerVertex

Flags

alphaBlend, averageColor, clampAlphaMax, clampAlphaMin, clampRGBMax, clampRGBMin, colorBlend, colorDisplayOption, computeShadows, displaceGeometry, flatShading, ignoreDoubleSided, lightingOnly, reuseShadows, sampleByFace, scaleFactor, shareUV, useLightShadows
Long name (short name) Argument types Properties
alphaBlend(abl) string createedit
When specified, indicates the type of alpha blend to be applied. Options are: "none", "overwrite", "add", "subtract", "multiply", "divide", "average". This option only applies when colors are being set. The default if this argument is not specified is "overwrite". The "none" options to not overwrite the existing value.
averageColor(ac) boolean createedit
When used, will mean to force the storage of shared colors for vertex level sampling. By default vertex level sampling stores unshared colors.
clampAlphaMax(amx) float createedit
When used, will mean to clamp the storage of alpha to a maximum
clampAlphaMin(amn) float createedit
When used, will mean to clamp the storage of alpha to a minimum
clampRGBMax(cmx) [float, float, float] createedit
When used, will mean to clamp the storage of RGB color to a maximum
clampRGBMin(cmn) [float, float, float] createedit
When used, will mean to clamp the storage of RGB color to a minimum
colorBlend(cbl) string createedit
When specified, indicates the type of color blend to be applied. Options are: "none", "overwrite", "add", "subtract", "multiply", "divide", "average". This option only applies when colors are being set. The default if this argument is not specified is "overwrite". The "none" options to not overwrite the existing value.
colorDisplayOption(cdo) boolean createedit
Change the display options on the mesh to display the vertex colors.
computeShadows(cs) boolean createedit
When used, shadow maps will be computed, saved, and reused during the sampling process.
displaceGeometry(dg) boolean createedit
When used, geometry will be displaced along the normals at the sampling positions, as opposed to storing color values. The default is to store colors.
flatShading(fs) boolean createedit
When used, flat shaded sampling will be computed. The default is smooth shading.
ignoreDoubleSided(ids) boolean createedit
When specified, the double sided flag will be ignored for prelighting.
lightingOnly(lo) boolean createedit
When used, incoming illumination will be computed as opposed to surface color an tranparency
reuseShadows(rs) boolean createedit
When used, if shadow maps were previosly computed and saved, then they will be reused during the sampling process. The computeShadows option must be enabled for this option to apply.
sampleByFace(bf) boolean createedit
When used, sample will occur at a per face level versus a per vertex level, which is the default behaviour
scaleFactor(sf) float createedit
When used, will scale the sampled value by the specified amount. The default scale factor is 1.0. Negative values are acceptable for displacement, but not for color values.
shareUV(su) boolean createedit
When used, UVs are shared at a vertex when sampled. By default UVs are forced to be unshared.
useLightShadows(ul) boolean createedit
When used, will use each lights shadow map options. Otherwise these options will be overrridden when the computeShadows, and/or reusedShadows option is enabled.
Flag can appear in Create mode of command Flag can appear in Edit mode of command
Flag can appear in Query mode of command Flag can have multiple arguments, passed either as a tuple or a list.

Python examples

import maya.cmds as cmds

# Example 1. Sample for color values.
#    a. No arguments. Will perform sampling of color + transparency at
#     the vertex level, and store color values for affected vertices.
#     No shadows will be computed.
cmds.polyGeoSampler()
# b. With shadows and illumination only
cmds.polyGeoSampler( lightingOnly=True, computeShadows=True )
# c. Sampling only complete selected faces
cmds.polyGeoSampler( sampleByFace=True )
# d. "Flat shading".
# Example 2. Sample for displacement values.
# a. Using displace option
cmds.polyGeoSampler( displaceGeometry=True )
# Example 3. Scaling the sampled data.
# a. Scaling option
cmds.polyGeoSampler( scaleFactor=0.1 )
# Example 4. Don't force unshared UV value usage, and force
# the storage of shared colors for vertices.
cmds.polyGeoSampler( shareUV=True, averageColor=True )
# Example 5. Clamping colors. In this example the alpha and
# RGB channels of the colors are clamped between a min of 0,0,0,1
# and a max of 1,2,1,0.5 .
cmds.polyGeoSampler( amn=0.0, amx=0.5, cmn=[0.0,0.0,0.0], cmx=[1.0,2.0,1.0] )
# Example 6. Multiply the new sample color values    with the existing
# colors stored on the geometry, but leave the alpha values
# as they were on the geometry.
cmds.polyGeoSampler( colorBlend='multiply', alphaBlend='none' )