Speed CHOP
Summary
The Speed CHOP converts speed (units per second) to distance (units) over a time range. More generally, you give it a rate (the CHOP input) and it outputs a cumulative value. For example, the Speed CHOP converts rotation rate (rotations per second) into the number of rotation turns. ( Math-heads recognize this as an 'integral', which calculates the area under a curve. The curve is the incoming channel values over a time range, the output is the area.)
If you send a Constant CHOP channel that has value 1 into the Speed CHOP, then the Speed CHOP output will increase by 1 every second. If you feed it -2, it will decrease by 2 every second, and if you feed it 0, the output will not change. Use a Trail CHOP to see its results. You can reset the Speed CHOP to 0 by pressing the Reset parameter, or by sending in a channel (whose value is greater than 0) into the second input.
The first input contains the channels to be 'integrated'. By default, the Speed CHOP is time-sliced, so it keeps adding/subtracting to the output each frame it cooks. If you turn off its Time Slice parameter and send it a CHOP with a fixed frame range (like a default Noise CHOP), you can see the cumulative value starting from 0.
The output is calculated by adding the input's channel values for every sample, divided by the samples per second of the Speed CHOP (typically 60), starting with the sample at the Start index. Negative input values reduce the output, positive values increase it. The cumulative values are put in the output channels.
When the CHOP is reset, its output can be set to any value via the Reset Value parameter.
When the second input is used to reset the output, where the second input is greater than 0, the area is reset and held to the reset value. For example, a Wave CHOP (which is negative half the time) when passed into the second input causes the output to be reset for half a cycle.
See also: Lookup CHOP, Timer CHOP, Count CHOP, Event CHOP
Parameters - Speed Page
order
- ⊞ - Determines the order of the integral to use. If the input is a velocity, a First Order integral will return the position. If the input is an acceleration, a Second Order integral will return the position, and a First Order integral will return the velocity.
- First
first
-
- Second
second
-
- Third
third
-
constant1
- Constant to add to the entire result after integrating once.
constant2
- Constant to add to the entire result after integrating twice.
constant3
- Constant to add to the entire result after integrating three times.
limittype
- ⊞ - Select limit options such as loop, clamp, or zigzag from the menu. The value will remain in the range from Min to less than Max.
- Off
off
- Do not limit the values.
- Clamp
clamp
- Simply cut the channel value off if it is out of the Maximum/Minimum range, and replace it with the Maximum or Minimum limit value.
- Loop
loop
- Continue the channel at the other end of the interval.
- Zigzag
zigzag
- Mirror the values back inside the interval.
min
- The minimum value the output channel can have.
max
- The maximum value the output channel can have.
speedsamples
- Applies the speed to each sample of the channel instead of across the whole channel. Useful for working with multi-sample channels.
resetcondition
- ⊞ - This menu determines how the Reset input triggers a reset of the channel(s).
- Off to On
offtoon
- Channels are reset when the Reset input goes off to on.
- While On
on
- Channels are reset when the Reset input goes on. The channel will hold the reset value until the input turns off.
- On to Off
ontooff
- Channels are reset when the Reset input goes on to off.
- While Off
off
- Channels are reset when the Reset input goes off. The channel will hold the reset value until the input turns on.
resetvalue
- The channel(s) is set to this value when reset.
reset
- While On, this toggle resets the channel(s) to the Reset Value.
resetpulse
- Click to instantly resets the channel(s) to the Reset Value.
resetonstart
- While On, the Speed CHOP will reset each time the .toe file is restarted. If the Speed CHOP's value gets too large it can start stepping as when it reaches the limit of CHOP's number resolution. This is useful for projects that run for a long time, restarting the file will reset this value.
Parameters - Common Page
timeslice
- Turning this on forces the channels to be "Time Sliced". A Time Slice is the time between the last cook frame and the current cook frame.
scope
- To determine which channels get affected, some CHOPs use a Scope string on the Common page. See Pattern Matching.
srselect
- ⊞ - Handle cases where multiple input CHOPs' sample rates are different. When Resampling occurs, the curves are interpolated according to the Interpolation Method Option, or "Linear" if the Interpolate Options are not available.
- Resample At First Input's Rate
first
- Use rate of first input to resample others.
- Resample At Maximum Rate
max
- Resample to the highest sample rate.
- Resample At Minimum Rate
min
- Resample to the lowest sample rate.
- Error If Rates Differ
err
- Doesn't accept conflicting sample rates.
exportmethod
- ⊞ - This will determine how to connect the CHOP channel to the parameter. Refer to the Export article for more information.
- DAT Table by Index
datindex
- Uses the docked DAT table and references the channel via the index of the channel in the CHOP.
- DAT Table by Name
datname
- Uses the docked DAT table and references the channel via the name of the channel in the CHOP.
- Channel Name is Path:Parameter
autoname
- The channel is the full destination of where to export to, such hasgeo1/transform1:tx
.
autoexportroot
- This path points to the root node where all of the paths that exporting by Channel Name is Path:Parameter are relative to.
exporttable
- The DAT used to hold the export information when using the DAT Table Export Methods (See above).
Operator Inputs
- Input 0: -
- Input 1: -
Info CHOP Channels
Extra Information for the Speed CHOP can be accessed via an Info CHOP.
Common CHOP Info Channels
- start - Start of the CHOP interval in samples.
- length - Number of samples in the CHOP.
- sample_rate - The samplerate of the channels in frames per second.
- num_channels - Number of channels in the CHOP.
- time_slice - 1 if CHOP is Time Slice enabled, 0 otherwise.
- export_sernum - A count of how often the export connections have been updated.
Common Operator Info Channels
- total_cooks - Number of times the operator has cooked since the process started.
- cook_time - Duration of the last cook in milliseconds.
- cook_frame - Frame number when this operator was last cooked relative to the component timeline.
- cook_abs_frame - Frame number when this operator was last cooked relative to the absolute time.
- cook_start_time - Time in milliseconds at which the operator started cooking in the frame it was cooked.
- cook_end_time - Time in milliseconds at which the operator finished cooking in the frame it was cooked.
- cooked_this_frame - 1 if operator was cooked this frame.
- warnings - Number of warnings in this operator if any.
- errors - Number of errors in this operator if any.
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