friz::Spring Class Reference

Accelerates toward the end value – if this acceleration takes it past the end value, it enters a mode where it acts like a simplified oscillating spring; the behavior of the oscillation can be loosened or tightened using the dampen parameter. More...

#include <spring.h>

Inheritance diagram for friz::Spring:

Public Member Functions
	Spring (float startVal, float endVal, float tolerance, float accel, float dampen)
Public Member Functions inherited from friz::ToleranceValue
	ToleranceValue (float startVal, float endVal, float tolerance)
float	getNextValue (int, int msSinceLastUpdate) override
	Calculate the next value in the sequence based on the delta time since last updated. Internally, we use an update rate of 1 kHz to recalculate values so that we can remain consistent as the actual animation frame rate changes.
bool	isFinished () override
	Test to see if this value has reached its end state.
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 () override
	Execute a single step of this curve's function.

Private Attributes
float	startAcceleration
	The initial acceleration for this value.
float	acceleration
	When we're in a damping state, the acceleration will change.
float	damping
	damping factor to apply when we need to oscillate toward end val.
float	velocity
	current velocity, updated with acceleration every frame.

Additional Inherited Members
Protected Attributes inherited from friz::ToleranceValue
float	tolerance
Protected Attributes inherited from friz::AnimatedValue
float	startVal
float	endVal
float	currentVal
bool	canceled { false }
bool	finished { false }

Detailed Description

Accelerates toward the end value – if this acceleration takes it past the end value, it enters a mode where it acts like a simplified oscillating spring; the behavior of the oscillation can be loosened or tightened using the dampen parameter.

Constructor & Destructor Documentation

Spring()

friz::Spring::Spring	(	float	startVal,
		float	endVal,
		float	tolerance,
		float	accel,
		float	dampen
	)

A curve that accelerates toward the end value, then oscillates toward it on overshoot.

Parameters

startVal	initial value
endVal	end value.
tolerance	How close do we need to be to stop animating?
accel	Velocity change on each update.
dampen	How much to dampen the oscillation, 0 < dampen < 1. smaller values dampen the oscillation faster.

Member Function Documentation

generateNextValue()

float friz::Spring::generateNextValue ( )

overrideprivatevirtual

Execute a single step of this curve's function.

Returns

next value.

Implements friz::ToleranceValue.

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

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