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This CHOP renames channels. Channels names from the input CHOP are matched using the From pattern, and are renamed to the corresponding name in the To pattern. Channels that do not match the From pattern are not affected.
The channel values and the channel order are not affected, only their names change.
(Note that the Constant CHOP (containing channel values of 0) added to another chop in a Math CHOP can also be used to rename channels.)
Sample Naming Patterns
The From and To parameters are any channel name creation
patterns like: chan[1-9:2]
or t[xyz]
. The From parameter also
allows matching patterns like chan* and ch? . For example:
Simple matching assuming an input of chan1 chan2 chan3:
From | To | Produces |
---|---|---|
chan1 chan2 chan3
|
tx ty tz
|
tx ty tz
|
chan[1-3]
|
t[xyz]
|
tx ty tz
|
chan[1-3]
|
tx ty tz rx
|
tx ty tz
|
chan[1-2]
|
tx ty
|
tx ty chan3
|
Simple matching assuming an input of tx ty t z:
t[xyz]
|
[XYZ]trans
|
Xtrans Ytrans Ztrans
|
Change channels that start with "bob" to channels that start with "carol":
bob*
|
carol*
|
Replace channels with "hand" in the middle to channels with "foot" in same place:
*hand*
|
*foot*
|
Swap words in a name, where the words are separated by :_
*_*
|
*(1)_*(0)
|
a_x changes to x_a
|
Wildcard matching, assuming an input of ch1 ch2 ch3:
ch?
|
t?
|
t1 t2 t3
|
*
|
op:*
|
op:ch1 op:ch2 op:ch3
|
*h*
|
*han*
|
chan1 chan2 chan3
|
*[1-3:2]
|
foot[11-13:2]
|
foot11 ch2 foot13
|
*
|
chan[3,1,2]
|
chan3 chan1 chan2
|
Parameters
Rename
From
The channel pattern to rename. See examples above.
To
The replacement pattern for the channel names. See examples above.
Common
Some of these parameters may not be available on all CHOP nodes.
Scope
To determine which channels get affected, some CHOPs have a scope string. Patterns can be used in the scope, for example *
(match all), and ?
(match single character).
The following are examples of possible channel name matching options:
chan2
Matches a single channel name.
chan3 tx ty tz
Matches four channel names, separated by spaces.
chan*
Matches each channel that starts with chan
.
*foot*
Matches each channel that has foot
in it.
t?
The ?
matches a single character. t?
matches two-character channels starting with t.
r[xyz]
Matches channels rx
, ry
and rz
.
blend[3-7:2]
Matches number ranges giving blend3
, blend5
, and blend7
.
blend[2-3,5,13]
Matches channels blend2
, blend3
, blend5
, blend13
.
t[xyz]
[xyz]
matches three characters, giving channels tx
, ty
and tz
.
Sample Rate Match
The Sample Rate Match Options handle cases where multiple input CHOPs’ sample rates are different.
Resample At First Input’s Rate
Use rate of first input to resample others.
Resample At Maximum Rate
Resample to highest sample rate.
Resample At Minimum Rate
Resample to the lowest sample rate.
Error if Rates Differ
Does not accept conflicting sample rates.
Units
The units for which time parameters are specified.
For example, you can specify the amount of time a lag should last for in seconds (default), frames (at the Houdini FPS), or samples (in the CHOP’s sample rate).
Note
When you change the Units parameter, it does not convert the existing parameters to the new units.
Time Slice
Time Slicing is a feature which boosts cooking performance and reduces memory usage. Traditionally, CHOPs calculate the channel over its entire frame range. If the channel does need to be evaluated every frame, then cooking the entire range of the channel is unnecessary. It is more efficient to calculate only the fraction of the channel that is needed. This fraction is known as a Time Slice.
Unload
Causes the memory consumed by a CHOP to be released after it is cooked and the data passed to the next CHOP.
Export Prefix
The Export prefix is prepended to CHOP channel names to determine where to export to.
For example, if the CHOP channel was named geo1:tx
, and the prefix was /obj
, the channel would be exported to /obj/geo1/tx
.
Note
You can leave the Export Prefix blank, but then your CHOP track names need to be absolute paths, such as obj:geo1:tx
.
Graph Color
Every CHOP has this option. Each CHOP gets a default color assigned for display in the Graph port, but you can override the color in the Common page under Graph Color. There are 36 RGB color combinations in the Palette.
Graph Color Step
When the graph displays the animation curves and a CHOP has two or more channels, this defines the difference in color from one channel to the next, giving a rainbow spectrum of colors.
Examples
Rename Example for Rename channel node
The Rename CHOP renames the channel names in a CHOP.
To visualize the channels in this demonstration, please enter the CHOP network.
For a complete list of the types of renaming possible, please see the Houdini documentation.
The following examples include this node.
DynamicLights Example for Dynamics channel node
DynamicPops Example for Dynamics channel node
SimpleIKSolver Example for IKSolver channel node
AverageSpeed Example for Vector channel node
See also |