1. Introduction

The Uize.Curve.Rubber module defines various "rubbery" easing curve function generators that emulate qualities of motion, like bounce and elasticity.

DEVELOPERS: Chris van Rensburg, with thanks to Robert Penner for his easing equations work

The Uize.Curve.Rubber module defines various "rubbery" easing curve function generators, some of which are based on the easing equations work of Robert Penner.

1.1. In A Nutshell

Whereas the Uize.Curve module provides some of the most commonly used ease-in, ease-out, ease-in-out, and ease-in-the-middle curve function generators, the Uize.Curve.Rubber module offers curve function generators for more exotic types of curves that emulate the complex properties of motion.

1.1.1. Credit Where Credit Is Due

Thanks go to Robert Penner for his work on his easing equations, which provided a starting point and inspiration for work that has been done in the Uize.Curve.Rubber module.

In some cases, his original methods have merely been refactored, such as with the Uize.Curve.Rubber.easeInElastic method and related elastic easing curve function generators provided in this module. In other cases, the original implementations have been completely replaced, such as with the Uize.Curve.Rubber.easeInBounce method and related bounce easing curve function generators provided in this module, with the new implementation being much more versatile than the original. Either way, his excellent work has been an inspiration.

1.1.2. Using the Curve Function Generators

Using the curve function generators in the Uize.Curve.Rubber module is just as easy as using those contained inside the Uize.Curve module.

Simply call the curve function generator static method, supplying parameter values as needed in order to produce a curve with the desired properties, and then provide that curve function to an instance of the Uize.Fade class, an instance of the Uize.Widget.HoverFader class, a static method of the Uize.Fx module, or any method or instance of a class that uses the Uize.Fade class to drive its animation or value interpolation.

EXAMPLE

{
defaultStyle:{width:150,marginLeft:90,letterSpacing:2,borderRightColor:'0'},
hoverStyle:{width:240,marginLeft:0,letterSpacing:9,borderRightColor:'f'},
}
);

In the above example, an instance of the Uize.Widget.HoverFader class is being added as a child widget of the page widget (which is assumed to already exist). For the fadeIn state property of the Uize.Widget.HoverFader instance, an elastic ease-out curve function is being supplied as a curve. For the fadeOut state property, a bounce ease-out curve function is being supplied as a curve. This will make the fade-in to the hover style have an elastic quality to it, and the fade-out to the default style have a bounce quality to it.

VISUALIZE IT

To better visualize how the "rubbery" easing curve function generators work and how they affect motion, visit the interactive Curve Explorer tool.

For an in-depth discussion on animation in the UIZE JavaScript Framework, and for a discussion on how this module fits into the larger picture, consult the guide JavaScript Animation and Effects and read through the section Curves.

1.2. Examples

There are no dedicated showcase example pages for the Uize.Curve.Rubber module.

SEARCH FOR EXAMPLES

Use the link below to search for example pages on the UIZE Web site that reference the Uize.Curve.Rubber module...

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1.3. Implementation Info

The Uize.Curve.Rubber module defines the Uize.Curve.Rubber package under the Uize.Curve namespace.

1.3.1. Features Introduced in This Module

The features listed in this section have been introduced in this module.

STATIC METHODS

STATIC PROPERTIES

1.3.2. Features Overridden in This Module

No features have been overridden in this module.

1.3.3. Features Inherited From Other Modules

This module has no inherited features.

1.3.4. Modules Directly Under This Namespace

There are no modules directly under this namespace.

1.3.5. Unit Tests

There is no dedicated unit tests module for the Uize.Curve.Rubber module.

2. Static Methods

2.1. Uize.Curve.Rubber.easeInBack

Back easing in - backtracking slightly, then reversing direction and moving to target.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeInBack (overshootFLOAT);

The overshootFLOAT parameter controls the amount of overshoot, and is typically a value in the range of 0 to Infinity (although negative values are also supported). Higher positive values for this parameter will produce greater overshoot. The default value of 1.70158 produces 10% overshoot. A value of 0 produces a cubic easing curve with no overshoot. Negative values lower than -3 for this parameter will produce increasing amounts of overshoot on the opposite side of output value range.

VARIATION

curveFUNC = Uize.Curve.Rubber.easeInBack ();

When the optional overshootFLOAT parameter is not specified, its value will be defaulted to 1.70158.

NOTES

 see also the companion Uize.Curve.Rubber.easeOutBack, Uize.Curve.Rubber.easeInOutBack, and Uize.Curve.Rubber.easeMiddleBack static methods thanks to Robert Penner for his original implementation

IMPLEMENTATION INFO

 this feature was introduced in this module

2.2. Uize.Curve.Rubber.easeInBounce

Bounce, easing in.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeInBounce (
bouncesINT,                  // number of bounces (optional)
bouncePeakCurveFUNCorFLOAT,  // bounciness, essentially (optional)
bounceWidthRatioFLOAT,       // ratio of current bounce width to previous (optional)
bounceCurveFUNCorFLOAT       // the shape of the curve of a bounce (optional)
);

2.2.1. Parameters

2.2.1.1. bouncesINT

An integer, specifying the number of bounces in the curve, with the default number of bounces being 4.

2.2.1.2. bouncePeakCurveFUNCorFLOAT

A function reference for a curve function, or a numerical value that will be resolved to a power curve function using the Uize.Curve.resolve method.

This paramter can be used to affect the bounciness or springiness of each bounce. Numerical values above 1 will produce progressively bouncier curves as the value of bouncePeakCurveFUNCorFLOAT is increased. Numerical values below -1 will produce progressively more dampened curves as the value of bouncePeakCurveFUNCorFLOAT is decreased.

When determining the height of the peak of an individual bounce, a curve function specified for the bouncePeakCurveFUNCorFLOAT parameter will be used to obtain a value, using the position of the midpoint of the bounce along the x-axis as the input value to the bounce peak curve function. Because the specified bounce peak curve is only sampled at the bounce midpoints, bounce peak curves with high amounts of detail will not affect the shape of the bounces, but only the heights of the bounce peaks (so detail will be lost, in other words).

For a linear curve, the value 1 can be specified for this parameter. The default value for this parameter is 1.76.

2.2.1.3. bounceWidthRatioFLOAT

A floating point number, specifying the ratio between the width of the current bounce and the width of the previous bounce.

The default value for this parameter is 2, which means that each bounce will be twice as wide as the previous bounce. When the value 1 is specified for this parameter, all bounces will have the same width. When negative values are specified for this parameter, then ratio will be resolved to a positive number by negating it and inverting it (dividing it into 1). In other words, the value -2 will result in a resolved ratio of .5, which will result in each bounce being half the width of the previous bounce. You can think of the values in the negative scale as being the ratio of the width of the current bounce to the width of the next bounce (once negated, of course).

For values of this parameter greater than 1, the higher the value, the less noticeable changing the number of bounces with the bouncesINT parameter will become. Similarly, on the opposite side of the spectrum, for values of bounceWidthRatioFLOAT less than -1, the lower the value, the less noticeable changing the number of bounces will become. If each bounce is much smaller or larger than the previous bounce, the bounces at one end of the curve will become very small and barely noticeable.

NOTE

It should be noted that for the ease-out version of this curve, and for the ease-out phase of the ease-in-out and ease-in-the-middle versions of this curve, the bounce width ratio is actually the ratio of the width of the current bounce to the width of the next bounce. This is as a result of the curve being rotated 180 degrees.

2.2.1.4. bounceCurveFUNCorFLOAT

A function reference for a curve function, or a numerical value that will be resolved to a power curve function using the Uize.Curve.resolve method.

The curve specified by the bounceCurveFUNCorFLOAT parameter will be used to generate points along the curve of an individual bounce. The specified curve is used to produce both the left and right halves of a bounce curve, on either side of the bounce's midpoint on the x-axis. For the opposite half, the bounce curve is flipped horizontally. The default value for this parameter is 2, which produces bounces using a quadratic ease-out power curve.

VARIATION 1

curveFUNC = Uize.Curve.Rubber.easeInBounce (
bouncesINT,bouncePeakCurveFUNCorFLOAT,bounceWidthRatioFLOAT
);

When no bounceCurveFUNCorFLOAT parameter is specified, its value will be defaulted to 2, representing a quadratic ease-out curve function.

VARIATION 2

curveFUNC = Uize.Curve.Rubber.easeInBounce (bouncesINT,bouncePeakCurveFUNCorFLOAT);

When no bounceWidthRatioFLOAT parameter is specified, its value will be defaulted to 2 (each bounce will be twice the width of the previous bounce).

VARIATION 3

curveFUNC = Uize.Curve.Rubber.easeInBounce (bouncesINT);

When no bouncePeakCurveFUNCorFLOAT parameter is specified, its value will be defaulted to 1.76.

VARIATION 4

curveFUNC = Uize.Curve.Rubber.easeInBounce ();

When no bouncesINT parameter is specified, its value will be defaulted to 4.

NOTES

IMPLEMENTATION INFO

 this feature was introduced in this module

2.3. Uize.Curve.Rubber.easeInElastic

Elastic easing in - exponentially growing sine wave.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeInElastic (periodFLOAT,amplitudeFLOAT);

2.3.1. Parameters

2.3.1.1. periodFLOAT

A floating point number between 0 to 25, representing the width of a single elastic stretch-past and spring-back cycle as a fraction of the total curve width.

A value of .1, for example, will produce a curve with 10 stretch-past and spring-back cycles, whereas a value of .2 will produce five such cycles. Ever higher values above 1 make the curve progressively more like an exponential curve. The default value for this parameter is .3.

2.3.1.2. amplitudeFLOAT

A floating point number in the range of 1 to Infinity.

Values greater than 1 produce more springy elastic curves with more pronounced peaks and greater overshoot. The default value for this parameter is 1.

2.3.2. Variations

VARIATION 1

curveFUNC = Uize.Curve.Rubber.easeInElastic (periodFLOAT);

When the optional amplitudeFLOAT parameter is not specified, its value will be defaulted to 1.

VARIATION 2

curveFUNC = Uize.Curve.Rubber.easeInElastic ();

When the optional periodFLOAT parameter is not specified, its value will be defaulted to .3.

NOTES

 see also the companion Uize.Curve.Rubber.easeOutElastic, Uize.Curve.Rubber.easeInOutElastic, and Uize.Curve.Rubber.easeMiddleElastic static methods thanks to Robert Penner for his original implementation

IMPLEMENTATION INFO

 this feature was introduced in this module

2.4. Uize.Curve.Rubber.easeInOutBack

Back easing in/out - backtracking slightly, then reversing direction and moving to target, then overshooting target, reversing, and finally coming back to target.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeInOutBack (overshootFLOAT);

For an in-depth discussion of the overshootFLOAT parameter, consult the reference for the related Uize.Curve.Rubber.easeInBack static method.

VARIATION

curveFUNC = Uize.Curve.Rubber.easeInOutBack ();

When the optional overshootFLOAT parameter is not specified, its value will be defaulted to 1.70158.

NOTES

 see also the companion Uize.Curve.Rubber.easeInBack, Uize.Curve.Rubber.easeOutBack, and Uize.Curve.Rubber.easeMiddleBack static methods thanks to Robert Penner for his original implementation

IMPLEMENTATION INFO

 this feature was introduced in this module

2.5. Uize.Curve.Rubber.easeInOutBounce

Bounce, easing in/out.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeInOutBounce (
bouncesINT,                  // number of bounces (optional)
bouncePeakCurveFUNCorFLOAT,  // bounciness, essentially (optional)
bounceWidthRatioFLOAT,       // ratio of current bounce width to previous (optional)
bounceCurveFUNCorFLOAT       // the shape of the curve of a bounce (optional)
);

VARIATIONS

curveFUNC = Uize.Curve.Rubber.easeInOutBounce (
bouncesINT,bouncePeakCurveFUNCorFLOAT,bounceWidthRatioFLOAT
);

curveFUNC = Uize.Curve.Rubber.easeInOutBounce (bouncesINT,bouncePeakCurveFUNCorFLOAT);

curveFUNC = Uize.Curve.Rubber.easeInOutBounce (bouncesINT);

curveFUNC = Uize.Curve.Rubber.easeInOutBounce ();

For a more in-depth discussion of this method's parameters and variations, consult the reference for the related Uize.Curve.Rubber.easeInBounce static method.

NOTES

IMPLEMENTATION INFO

 this feature was introduced in this module

2.6. Uize.Curve.Rubber.easeInOutElastic

Elastic easing in/out - exponentially building then decaying sine wave.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeInOutElastic (periodFLOAT,amplitudeFLOAT);

VARIATIONS

curveFUNC = Uize.Curve.Rubber.easeInOutElastic (periodFLOAT);
curveFUNC = Uize.Curve.Rubber.easeInOutElastic ();

For a more in-depth discussion of this method's parameters and variations, consult the reference for the related Uize.Curve.Rubber.easeInElastic static method.

NOTES

 see also the companion Uize.Curve.Rubber.easeInElastic, Uize.Curve.Rubber.easeOutElastic, and Uize.Curve.Rubber.easeMiddleElastic static methods thanks to Robert Penner for his original implementation

IMPLEMENTATION INFO

 this feature was introduced in this module

2.7. Uize.Curve.Rubber.easeMiddleBack

Back easing in the middle - overshooting the middle, backtracking to the middle, then backtracking even further towards the beginning, then finally moving to target.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeMiddleBack (overshootFLOAT);

For an in-depth discussion of the overshootFLOAT parameter, consult the reference for the related Uize.Curve.Rubber.easeInBack static method.

VARIATION

curveFUNC = Uize.Curve.Rubber.easeMiddleBack ();

When the optional overshootFLOAT parameter is not specified, its value will be defaulted to 1.70158.

NOTES

 see also the companion Uize.Curve.Rubber.easeInBack, Uize.Curve.Rubber.easeOutBack, and Uize.Curve.Rubber.easeInOutBack static methods thanks to Robert Penner for his original implementation

IMPLEMENTATION INFO

 this feature was introduced in this module

2.8. Uize.Curve.Rubber.easeMiddleBounce

Bounce, easing in the middle.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeMiddleBounce (
bouncesINT,                  // number of bounces (optional)
bouncePeakCurveFUNCorFLOAT,  // bounciness, essentially (optional)
bounceWidthRatioFLOAT,       // ratio of current bounce width to previous (optional)
bounceCurveFUNCorFLOAT       // the shape of the curve of a bounce (optional)
);

VARIATIONS

curveFUNC = Uize.Curve.Rubber.easeMiddleBounce (
bouncesINT,bouncePeakCurveFUNCorFLOAT,bounceWidthRatioFLOAT
);

curveFUNC = Uize.Curve.Rubber.easeMiddleBounce (bouncesINT,bouncePeakCurveFUNCorFLOAT);

curveFUNC = Uize.Curve.Rubber.easeMiddleBounce (bouncesINT);

curveFUNC = Uize.Curve.Rubber.easeMiddleBounce ();

For a more in-depth discussion of this method's parameters and variations, consult the reference for the related Uize.Curve.Rubber.easeInBounce static method.

NOTES

IMPLEMENTATION INFO

 this feature was introduced in this module

2.9. Uize.Curve.Rubber.easeMiddleElastic

Elastic easing in the middle - exponentially decaying then building sine wave.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeMiddleElastic (periodFLOAT,amplitudeFLOAT);

VARIATIONS

curveFUNC = Uize.Curve.Rubber.easeMiddleElastic (periodFLOAT);
curveFUNC = Uize.Curve.Rubber.easeMiddleElastic ();

For a more in-depth discussion of this method's parameters and variations, consult the reference for the related Uize.Curve.Rubber.easeInElastic static method.

NOTES

 see also the companion Uize.Curve.Rubber.easeInElastic, Uize.Curve.Rubber.easeOutElastic, and Uize.Curve.Rubber.easeInOutElastic static methods thanks to Robert Penner for his original implementation

IMPLEMENTATION INFO

 this feature was introduced in this module

2.10. Uize.Curve.Rubber.easeOutBack

Back easing out - moving towards target, overshooting it slightly, then reversing and coming back to target.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeOutBack (overshootFLOAT);

For an in-depth discussion of the overshootFLOAT parameter, consult the reference for the related Uize.Curve.Rubber.easeInBack static method.

VARIATION

curveFUNC = Uize.Curve.Rubber.easeOutBack ();

When the optional overshootFLOAT parameter is not specified, its value will be defaulted to 1.70158.

NOTES

 see also the companion Uize.Curve.Rubber.easeInBack, Uize.Curve.Rubber.easeInOutBack, and Uize.Curve.Rubber.easeMiddleBack static methods thanks to Robert Penner for his original implementation

IMPLEMENTATION INFO

 this feature was introduced in this module

2.11. Uize.Curve.Rubber.easeOutBounce

Bounce, easing out.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeOutBounce (
bouncesINT,                  // number of bounces (optional)
bouncePeakCurveFUNCorFLOAT,  // bounciness, essentially (optional)
bounceWidthRatioFLOAT,       // ratio of current bounce width to next (optional)
bounceCurveFUNCorFLOAT       // the shape of the curve of a bounce (optional)
);

VARIATIONS

curveFUNC = Uize.Curve.Rubber.easeOutBounce (
bouncesINT,bouncePeakCurveFUNCorFLOAT,bounceWidthRatioFLOAT
);

curveFUNC = Uize.Curve.Rubber.easeOutBounce (bouncesINT,bouncePeakCurveFUNCorFLOAT);

curveFUNC = Uize.Curve.Rubber.easeOutBounce (bouncesINT);

curveFUNC = Uize.Curve.Rubber.easeOutBounce ();

For a more in-depth discussion of this method's parameters and variations, consult the reference for the related Uize.Curve.Rubber.easeInBounce static method.

NOTES

IMPLEMENTATION INFO

 this feature was introduced in this module

2.12. Uize.Curve.Rubber.easeOutElastic

Elastic easing out - exponentially decaying sine wave.

SYNTAX

curveFUNC = Uize.Curve.Rubber.easeOutElastic (periodFLOAT,amplitudeFLOAT);

VARIATIONS

curveFUNC = Uize.Curve.Rubber.easeOutElastic (periodFLOAT);
curveFUNC = Uize.Curve.Rubber.easeOutElastic ();

For a more in-depth discussion of this method's parameters and variations, consult the reference for the related Uize.Curve.Rubber.easeInElastic static method.

NOTES

 see also the companion Uize.Curve.Rubber.easeInElastic, Uize.Curve.Rubber.easeInOutElastic, and Uize.Curve.Rubber.easeMiddleElastic static methods thanks to Robert Penner for his original implementation

IMPLEMENTATION INFO

 this feature was introduced in this module

3. Static Properties

3.1. Uize.Curve.Rubber.moduleName

IMPLEMENTATION INFO

 this feature was introduced in this module

3.2. Uize.Curve.Rubber.pathToResources

IMPLEMENTATION INFO

 this feature was introduced in this module