Animation Maker

Ease curves in Nuke, with just a right-click.

menu

I have made a little extension to Nuke that when right-clicking any animatable value on any node you can choose ‘Animation Maker…‘ from the pop up menu and a whole suite of customisable animation curves can be chosen. When you’re happy, it generates the expression to form that curve and puts it into the knob in question. It also adds a user tab to the node with sliders so you can refine it on the fly. No extra nodes or expression lines in your script and it’s available everywhere.

It does all the maths for you.

Contains ease curves such as Quad, Exponential, Bounce and Elastic. Wave curves such as Sine, Random, Noise, Triangle and Sawtooth. Options to combine a wave with an ease curve, turn a wave into a ‘square’ version or create a sequence of blips at certain intervals.

All contained in one .py file. No gizmos required. Just put the file in your .nuke directory (or wherever your plugins directory is located), then add two lines to your menu.py.

Download here

This supersedes my previous WaveMaker tool, so no need to have both installed.

AnimMaker

Pop up dialogue in Ease mode, showing the motion with a growing circle, a moving circle and a circle fading from black to white.

AnimMaker2

Pop up dialogue in Wave mode showing an example noise wave.

tab

When CREATE is pressed, a new tab like this will appear on the node.

expression

An expression will be put into the chosen knob which is linked to the new tab’s controls.

easeout

An example Expo Ease Out curve

ease

An example Expo Ease In curve

easeinandout

An example Expo Ease In & Out curve

bounce

An example Bounce curve

elastic

An example Elastic curve

noise

An example Noise wave

waveEase

An example Sine wave combined with a Linear ease in.

blip

An example Blip animation made from a Sine wave.

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Nuke: blip expressions to copy and paste

Using waves to drive animation in Nuke – part 2

In my previous article on this subject I gave some examples of expressions that you can just copy and paste into any value in Nuke to quickly create an infinitely repeating animating pattern. I was asked in the comments how to do a ‘blink expression every x frames’. I answered with ‘just use the square wave example’, but I realised that’s not what he was after. In this article I’ll give you some expressions that can be used for such a blink or ‘blip’ animation curve.

I have also made a new version of my gizmo WaveMaker that incorporates all of this, so you can download that if you’d prefer. It’s now in .nk format rather than .gizmo so it’s easier to share.

Square on/off blip every n frames

(((((sin(((frame*(pi*2/(freq/2))/2)+offset))+1)/2)) > cutoff ? 1 : 0) * (maxVal-minVal) ) + minVal

(Where ‘freq’ is the number of frames between blips, ‘offset’ is the time offset, ‘cutoff’ is a value between 0 and 1 which controls the width of each blip, ‘minVal’ is the lower value, ‘maxVal’ is the upper value. As in the previous article, either replace these variable names with your values, or better still, create a NoOp node, add some user knobs with those names and you’ll be able to adjust it on the fly)

Simpler version: ((( sin( ( ( frame * ( pi * 2 / ( 5 / 2 ) ) / 2 ) + 0.5 ) ) + 1 ) / 2 ) ) > 0.95 ? 1 : 0

(Blip pattern between 0 and 1, replace the ‘5’ to adjust amount of frames between blips, adjust the ‘0.5’ to move the whole thing back and forth in time, and adjust the ‘0.95’ to adjust the width of the blips)

So what’s it doing?

It’s really just a simple sine wave with another expression applied to see when that sine wave goes above the cutoff point. If so, set the value to 1, if not, set it to zero. If a high enough cutoff point is given (like 0.95) most of the time the sine wave will be below that value and only at the very tip of the peak go above it. The lower the cutoff, the longer the peak rises above the cutoff point and so the blip gets wider.

But if you need something a bit smoother than a simple on/off, I’ve also made this version:

Smooth pulse-like blip every n frames

(min((max((((((sin(((frame*(pi*2/(freq/2))/2)+offset))+1)/2)) > cutoff ? (((sin(((frame*(pi*2/(freq/2))/2)+offset))+1)/2)) : 0)) – cutoff,0) * (1/(1-cutoff)) * 1.001),1) * (maxVal-minVal) ) + minVal

Slightly simpler version: (min( (max( ((((( sin( (( frame*( pi * 2 / ( 10 / 2 ) ) / 2 ) + 1.55 )) + 1 ) / 2 )) > 0.7 ? (((sin( ( (frame * ( pi * 2 / ( 10 / 2 ) ) / 2 ) + 1.55 ) ) + 1 ) / 2 )) : 0 )) – 0.7 , 0 ) * ( 1 / ( 1 – 0.7 )) * 1.001) , 1 ))

(Smooth blip pattern between 0 and 1, replace the ’10’s to adjust amount of frames between blips, adjust the ‘1.55’s to move the whole thing back and forth in time, and adjust the ‘0.7’s to adjust the width of the blips)

Multiple blips

To make a complex repeating pattern of blips, create several user knobs using the above expressions, set to different values, then in another user knob max them all together:

max( max( blip1, blip2 ) , blip3 )

Manual looping

Remember, if you just need a quick repeating pattern for one thing in one shot, then building all these expressions is probably overkill because you can just draw a pattern in the curve editor, then tell Nuke to loop that pattern. This is more for the cases where you may have several things blinking on and off at different rates (perhaps a HUD, graphics display or warning lights on buildings), and you may need to go and adjust them all later. I personally wouldn’t go to the trouble of building all the knobs each time, that’s why I built BlipMaker into my WaveMaker gizmo so it’s available whenever I need it. My article where I took all my expressions from WaveMaker and made them available for quick copying and pasting has proved rather popular though so I thought I’d do the same for BlipMaker.

Nuke wave expressions to copy and paste

Using waves to drive animation in Nuke

Creating repeating or random patterns in the curve editor can often be made easier by using expressions that describe a curve. Sine, noise and random functions are very useful, but forcing them into the exact shape you want can be a little time-consuming. So, following my previous post talking about my gizmo WaveMaker, I thought I’d share some handy expressions it uses which you can copy and paste straight from this blog when you need them, rather than installing the gizmo itself.

Edit on 12/10/2013: I have just released Animation Maker, a handy Nuke extension that contains all the waves talked about here, plus lots of Ease curves too. See the article here.

Click on any value in any node, press ‘=’ and type an expression. Right click and choose ‘Curve Editor…’ to view the curve.

These expressions give you full control over the width, height and position of the wave. Either replace the following variables with your actual values, or add your own sliders to the node so you can adjust them on the fly (see below for how to do that).

waveLength (how many frames between peaks of the wave)
minVal (the wave will never go below this value)
maxVal (the wave will never go above this value)
offset (shift the wave back and forth in time)

Edit on 15/01/12: I have also provided simple versions that will work immediately once you paste them in. They will just produce a wave between 0 and 1 but that may be all you need.

Some useful wave expressions:

Sine

(((sin(((frame*(pi*2/(waveLength/2))/2)+offset))+1)/2) * (maxVal-minVal) ) + minVal

Simple version:  (sin(frame/5)/2)+0.5  (Wave between 0 and 1, replace the ‘5’ to adjust speed) 

Square

((((sin(((frame*(pi*2/(waveLength/2))/2)+offset))+1)/2) * (maxVal-minVal) ) + minVal) > ((maxVal/2)+(minVal/2)) ? maxVal : minVal

Simple version:  (sin(frame/5)/2)+0.5 > 0.5 ? 1 : 0  (Wave between 0 and 1, replace the ‘5’ to adjust speed)

Triangle

(((((2*asin(sin(2*pi*(frame/waveLength)+offset)))/pi) / 2)+0.5) * (maxVal-minVal) ) + minVal

Simple version:  (((2*asin(sin(2*pi*(frame/30))))/pi) / 2)+0.5  (Wave between 0 and 1, replace the ’30’ to adjust speed)

Sawtooth

((1/waveLength)*(((frame-1)+offset) % waveLength) * (maxVal-minVal) ) + minVal

Simple version:  ( 1 / 30 )*( (frame-1) % 30)  (Wave between 0 and 1, replace the two ’30’s to adjust speed)

Random

((random((frame/waveLength)+offset)) * (maxVal-minVal) ) + minVal

Simple version:  random(frame/5)  (Wave between 0 and 1, replace the ‘5’ to adjust speed)

Noise

(((1*(noise((frame/waveLength)+offset))+1 ) /2 ) * (maxVal-minVal) ) + minVal

Simple version:  (noise(frame/5)/2)+0.5  (Wave between 0 and 1, replace the ‘5’ to adjust speed)

Bounce

((sin(((frame/waveLength)*pi)+offset)>0?sin(((frame/waveLength)*pi)+offset):cos((((frame/waveLength)*pi)+offset)+(pi/2))) * (maxVal-minVal) ) + minVal

Simple version:  sin(((frame/10)*pi)) > 0 ? sin(((frame/10)*pi)) : cos(((frame/10)*pi)+(pi/2))  (Wave between 0 and 1, replace the ’10’s to adjust speed)

Sawtooth (parabolic)

((sin((1/(pi/2))*(((frame-1)+offset)/(waveLength/2.46666666)) % (pi/2)))>0.99999? 1 : (sin((1/(pi/2))*(((frame-1)+offset)/(waveLength/2.46666666)) % (pi/2))) * (maxVal-minVal) ) + minVal

Sawtooth (parabolic, reversed)

((cos((1/(pi/2))*(((frame-1)+offset)/(waveLength/2.46666666)) % (pi/2)))>0.99999? 1 : (cos((1/(pi/2))*(((frame-1)+offset)/(waveLength/2.46666666)) % (pi/2))) * (maxVal-minVal) ) + minVal

Sawtooth (exponential)

((((((exp((1/(pi/2))*(((frame-1)+offset)/(waveLength/4.934802)) % pi*2)))/534.5)) – 0.00186741)>0.999987? 1 : (((((exp((1/(pi/2))*(((frame-1)+offset)/(waveLength/4.934802)) % pi*2)))/534.5)) – 0.00186741) * (maxVal-minVal) ) + minVal

*Note: the waveLength value doesn’t really correspond to the peaks in Random or Noise waves, so you will probably need a smaller wavelength value for those.

To add your own sliders:

  1. Right click your node, choose ‘Manage User Knobs…’
  2. Click ‘Add…’ and choose ‘Floating Point Slider…’
  3. Type ‘waveLength’ into its name and label boxes. Give it a max and min value of 0 and 100.
  4. Repeat with each of the four variable names (above).

These  four sliders will appear in the ‘User’ tab of the node. You may find it better to create a ‘NoOp’ node, add the above sliders, but also add several extra floating-point sliders called ‘Wave1’, ‘Wave2’, ‘Wave3’ etc. This way you can use the same sliders to control several different expressions, then you can use any one of them to drive animations in your script.

It’s worth noting many of these wave shapes can be created using a few keyframes and telling nuke to ‘loop’ that section. But using expressions with a few sliders you can mess around with them a lot easier. Besides, maths is fun.

One more thing:

To describe a CIRCLE, put this in the X: 

(((sin(((frame*(pi*2/(waveLength/2))/2)+offset))+1)/2) * (maxVal-minVal) ) + minVal

and this in Y:

(((cos(((frame*(pi*2/(waveLength/2))/2)+offset))+1)/2) * (maxVal-minVal) ) + minVal

Simple version (X): sin(frame/5)*300

Simple version (Y): cos(frame/5)*300

(replace the ‘5’ to adjust speed, replace the ‘300’ to change the circle size)

Tip: put it in the X and Z in a TransformGeo after a Card to make a carousel type animation.