blob: dd9044507e2b5ac658b95df3a6a31a0b63ad71f8 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
/*
* Copyright 2009 Phil Burk, Mobileer Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.jsyn.unitgen;
import com.jsyn.ports.UnitInputPort;
import com.jsyn.ports.UnitVariablePort;
/**
* A ramp whose function over time is continuous in value and in slope. Also called an "S curve".
*
* @author Phil Burk (C) 2009 Mobileer Inc
* @version 016
* @see LinearRamp
* @see ExponentialRamp
* @see AsymptoticRamp
*/
public class ContinuousRamp extends UnitFilter {
public UnitVariablePort current;
/**
* Time it takes to get from current value to input value when input is changed. Default value
* is 1.0 seconds.
*/
public UnitInputPort time;
private double previousInput = Double.MIN_VALUE;
// Coefficients for cubic polynomial.
private double a;
private double b;
private double d;
private int framesLeft;
/* Define Unit Ports used by connect() and set(). */
public ContinuousRamp() {
addPort(time = new UnitInputPort(1, "Time", 1.0));
addPort(current = new UnitVariablePort("Current"));
}
@Override
public void generate(int start, int limit) {
double[] outputs = output.getValues();
double[] inputs = input.getValues();
double currentTime = time.getValues()[0];
double currentValue = current.getValue();
double inputValue = currentValue;
for (int i = start; i < limit; i++) {
inputValue = inputs[i];
double x;
if (inputValue != previousInput) {
x = framesLeft;
// Calculate coefficients.
double currentSlope = x * ((3 * a * x) + (2 * b));
framesLeft = (int) (getSynthesisEngine().getFrameRate() * currentTime);
if (framesLeft < 1) {
framesLeft = 1;
}
x = framesLeft;
// Calculate coefficients.
d = inputValue;
double xsq = x * x;
b = ((3 * currentValue) - (currentSlope * x) - (3 * d)) / xsq;
a = (currentSlope - (2 * b * x)) / (3 * xsq);
previousInput = inputValue;
}
if (framesLeft > 0) {
x = --framesLeft;
// Cubic polynomial. c==0
currentValue = (x * (x * ((x * a) + b))) + d;
}
outputs[i] = currentValue;
}
current.setValue(currentValue);
}
}
|
