1 files changed, 69 insertions, 0 deletions
diff --git a/src/main/java/com/jsyn/unitgen/SampleGrainSource.java b/src/main/java/com/jsyn/unitgen/SampleGrainSource.java
new file mode 100644
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+++ b/src/main/java/com/jsyn/unitgen/SampleGrainSource.java
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+/*
+ * 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.data.FloatSample;
+
+public class SampleGrainSource extends GrainCommon implements GrainSource {
+    private FloatSample sample;
+    private double position; // ranges from -1.0 to 1.0
+    private double positionRange;
+    private double phase; // ranges from 0.0 to 1.0
+    private double phaseIncrement;
+    private int numFramesGuarded;
+    private static final double MAX_PHASE = 0.9999999999;
+
+    @Override
+    public double next() {
+        phase += phaseIncrement;
+        if (phase > MAX_PHASE) {
+            phase = MAX_PHASE;
+        }
+        double fractionalIndex = phase * numFramesGuarded;
+        return sample.interpolate(fractionalIndex);
+    }
+
+    @Override
+    public void setRate(double rate) {
+        phaseIncrement = rate * sample.getFrameRate() / (getFrameRate() * numFramesGuarded);
+    }
+
+    public void setSample(FloatSample sample) {
+        this.sample = sample;
+        numFramesGuarded = sample.getNumFrames() - 1;
+    }
+
+    public void setPosition(double position) {
+        this.position = position;
+    }
+
+    @Override
+    public void reset() {
+        double randomPosition = position + (positionRange * (Math.random() - 0.5));
+        phase = (randomPosition * 0.5) + 0.5;
+        if (phase < 0.0) {
+            phase = 0.0;
+        } else if (phase > MAX_PHASE) {
+            phase = MAX_PHASE;
+        }
+    }
+
+    public void setPositionRange(double positionRange) {
+        this.positionRange = positionRange;
+    }
+
+}