friz::Constant Class Reference

A class that generates a single constant value for its duration. More...

#include <constant.h>

Inheritance diagram for friz::Constant:

Public Member Functions
	Constant (float value, int duration)
	Constant (float, float endVal, int duration)
	An alternate constructor that can be used by the makeAnimation() factory function, which requires that all animation effects have separate start and end values. We ignore anything passed to the startValue argument.
Public Member Functions inherited from friz::TimedValue
	TimedValue (float startVal, float endVal, int duration_)
float	getNextValue (int msElapsed, int) override
bool	isFinished () override
Public Member Functions inherited from friz::AnimatedValue
	AnimatedValue (float startVal_, float endVal_)
	Base class init for the animated value classes.
virtual float	getNextValue (int msElapsed, int msSinceLastUpdate)=0
float	getEndValue () const
	get the ending state of this value object. When we cancel an in-progress animation, we may need to snap to the end value, and this gives a way to get there immediately.
virtual bool	isFinished ()=0
virtual bool	updateTarget (float)
	Attempt to change the end value of an animation that's currently in process.
void	cancel (bool moveToEndPosition)
	Cancel an in-progress animation.

Private Member Functions
float	generateNextValue (float progress) override
	generate the value according to progress in time.

Additional Inherited Members
Protected Member Functions inherited from friz::TimedValue
float	scale (float curvePoint)
	Given a fractional curve point (typically) in the range (0.f..1.f), interpolate this point between this value's start and end points.
Protected Attributes inherited from friz::TimedValue
int	duration
	duration of the event in ms.
Protected Attributes inherited from friz::AnimatedValue
float	startVal
float	endVal
float	currentVal
bool	canceled { false }
bool	finished { false }

Detailed Description

A class that generates a single constant value for its duration.

Wait – why would you need a constant value when you're trying to animate?

Consider this case: I have an an animation that's cyclic, and I want to be able to set it to run for some number of cycles that I don't know at compile time. An easy way to do this is to create an Animation object that has a Constant value in it, and in the OnCompletion() callback, check to see if that value is > 0 – if not, immediately recreate the animation, but decrement the constant loop count value.

Constructor & Destructor Documentation

Constant() [1/2]

friz::Constant::Constant	(	float	value,
		int	duration
	)

A value that doesn't change.

Parameters

value	Value to generate.
duration	# of milliseconds the effect should take.

Constant() [2/2]

friz::Constant::Constant	(	float	,
		float	endVal,
		int	duration
	)

An alternate constructor that can be used by the makeAnimation() factory function, which requires that all animation effects have separate start and end values. We ignore anything passed to the startValue argument.

Parameters

startVal	ignored
endVal	The only value this effect wil emit.
duration	in milliseconds.

Member Function Documentation

generateNextValue()

float friz::Constant::generateNextValue ( float  progress )

overrideprivatevirtual

generate the value according to progress in time.

Parameters

progress

position in the animation (0.0..1.0)

Returns

next value.

Implements friz::TimedValue.

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The documentation for this class was generated from the following files:

• Source/friz/curves/constant.h
• Source/friz/curves/constant.cpp