diff options
Diffstat (limited to 'src/main/java/org/apache/commons/math3/analysis/interpolation/InterpolatingMicrosphere2D.java')
-rw-r--r-- | src/main/java/org/apache/commons/math3/analysis/interpolation/InterpolatingMicrosphere2D.java | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/src/main/java/org/apache/commons/math3/analysis/interpolation/InterpolatingMicrosphere2D.java b/src/main/java/org/apache/commons/math3/analysis/interpolation/InterpolatingMicrosphere2D.java new file mode 100644 index 0000000..fdc01b2 --- /dev/null +++ b/src/main/java/org/apache/commons/math3/analysis/interpolation/InterpolatingMicrosphere2D.java @@ -0,0 +1,87 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You 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 org.apache.commons.math3.analysis.interpolation; + +import org.apache.commons.math3.util.FastMath; +import org.apache.commons.math3.util.MathUtils; + +/** + * Utility class for the {@link MicrosphereProjectionInterpolator} algorithm. + * For 2D interpolation, this class constructs the microsphere as a series of + * evenly spaced facets (rather than generating random normals as in the + * base implementation). + * + * @since 3.6 + */ +public class InterpolatingMicrosphere2D extends InterpolatingMicrosphere { + /** Space dimension. */ + private static final int DIMENSION = 2; + + /** + * Create a sphere from vectors regularly sampled around a circle. + * + * @param size Number of surface elements of the sphere. + * @param maxDarkFraction Maximum fraction of the facets that can be dark. + * If the fraction of "non-illuminated" facets is larger, no estimation + * of the value will be performed, and the {@code background} value will + * be returned instead. + * @param darkThreshold Value of the illumination below which a facet is + * considered dark. + * @param background Value returned when the {@code maxDarkFraction} + * threshold is exceeded. + * @throws org.apache.commons.math3.exception.NotStrictlyPositiveException + * if {@code size <= 0}. + * @throws org.apache.commons.math3.exception.NotPositiveException if + * {@code darkThreshold < 0}. + * @throws org.apache.commons.math3.exception.OutOfRangeException if + * {@code maxDarkFraction} does not belong to the interval {@code [0, 1]}. + */ + public InterpolatingMicrosphere2D(int size, + double maxDarkFraction, + double darkThreshold, + double background) { + super(DIMENSION, size, maxDarkFraction, darkThreshold, background); + + // Generate the microsphere normals. + for (int i = 0; i < size; i++) { + final double angle = i * MathUtils.TWO_PI / size; + + add(new double[] { FastMath.cos(angle), + FastMath.sin(angle) }, + false); + } + } + + /** + * Copy constructor. + * + * @param other Instance to copy. + */ + protected InterpolatingMicrosphere2D(InterpolatingMicrosphere2D other) { + super(other); + } + + /** + * Perform a copy. + * + * @return a copy of this instance. + */ + @Override + public InterpolatingMicrosphere2D copy() { + return new InterpolatingMicrosphere2D(this); + } +} |