/*
- * Jalview - A Sequence Alignment Editor and Viewer (Version 2.8.2)
- * Copyright (C) 2014 The Jalview Authors
+ * Jalview - A Sequence Alignment Editor and Viewer ($$Version-Rel$$)
+ * Copyright (C) $$Year-Rel$$ The Jalview Authors
*
* This file is part of Jalview.
*
* Jalview is free software: you can redistribute it and/or
* modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+ * as published by the Free Software Foundation, either version 3
+ * of the License, or (at your option) any later version.
*
* Jalview is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU General Public License for more details.
*
- * You should have received a copy of the GNU General Public License along with Jalview. If not, see <http://www.gnu.org/licenses/>.
+ * You should have received a copy of the GNU General Public License
+ * along with Jalview. If not, see <http://www.gnu.org/licenses/>.
* The Jalview Authors are detailed in the 'AUTHORS' file.
*/
package jalview.math;
+import jalview.datamodel.Point;
+
+import java.util.HashMap;
+import java.util.Map;
+
/**
- * DOCUMENT ME!
- *
- * @author $author$
- * @version $Revision$
+ * Model for a 3x3 matrix which provides methods for rotation in 3-D space
*/
public class RotatableMatrix
{
- float[][] matrix;
+ private static final int DIMS = 3;
- float[] temp;
+ /*
+ * cache the most used rotations: +/- 1, 2, 3, 4 degrees around x or y axis
+ */
+ private static Map<Axis, Map<Float, float[][]>> cachedRotations;
- float[][] rot;
+ static
+ {
+ cachedRotations = new HashMap<>();
+ for (Axis axis : Axis.values())
+ {
+ HashMap<Float, float[][]> map = new HashMap<>();
+ cachedRotations.put(axis, map);
+ for (int deg = 1; deg < 5; deg++)
+ {
+ float[][] rotation = getRotation(deg, axis);
+ map.put(Float.valueOf(deg), rotation);
+ rotation = getRotation(-deg, axis);
+ map.put(Float.valueOf(-deg), rotation);
+ }
+ }
+ }
- /**
- * Creates a new RotatableMatrix object.
- *
- * @param rows
- * DOCUMENT ME!
- * @param cols
- * DOCUMENT ME!
- */
- public RotatableMatrix(int rows, int cols)
+ public enum Axis
{
- matrix = new float[rows][cols];
+ X, Y, Z
+ };
- temp = new float[3];
+ float[][] matrix;
- rot = new float[3][3];
+ /**
+ * Constructor creates a new identity matrix (all values zero except for 1 on
+ * the diagonal)
+ */
+ public RotatableMatrix()
+ {
+ matrix = new float[DIMS][DIMS];
+ for (int j = 0; j < DIMS; j++)
+ {
+ matrix[j][j] = 1f;
+ }
}
/**
- * DOCUMENT ME!
+ * Sets the value at position (i, j) of the matrix
*
* @param i
- * DOCUMENT ME!
* @param j
- * DOCUMENT ME!
* @param value
- * DOCUMENT ME!
*/
- public void addElement(int i, int j, float value)
+ public void setValue(int i, int j, float value)
{
matrix[i][j] = value;
}
/**
- * DOCUMENT ME!
+ * Answers the value at position (i, j) of the matrix
+ *
+ * @param i
+ * @param j
+ * @return
+ */
+ public float getValue(int i, int j)
+ {
+ return matrix[i][j];
+ }
+
+ /**
+ * Prints the matrix in rows of space-delimited values
*/
public void print()
{
- System.out.println(matrix[0][0] + " " + matrix[0][1] + " "
- + matrix[0][2]);
+ System.out.println(
+ matrix[0][0] + " " + matrix[0][1] + " " + matrix[0][2]);
- System.out.println(matrix[1][0] + " " + matrix[1][1] + " "
- + matrix[1][2]);
+ System.out.println(
+ matrix[1][0] + " " + matrix[1][1] + " " + matrix[1][2]);
- System.out.println(matrix[2][0] + " " + matrix[2][1] + " "
- + matrix[2][2]);
+ System.out.println(
+ matrix[2][0] + " " + matrix[2][1] + " " + matrix[2][2]);
}
/**
- * DOCUMENT ME!
+ * Rotates the matrix through the specified number of degrees around the
+ * specified axis
*
* @param degrees
- * DOCUMENT ME!
* @param axis
- * DOCUMENT ME!
*/
- public void rotate(float degrees, char axis)
+ public void rotate(float degrees, Axis axis)
{
- float costheta = (float) Math.cos((degrees * Math.PI) / (float) 180.0);
+ float[][] rot = getRotation(degrees, axis);
- float sintheta = (float) Math.sin((degrees * Math.PI) / (float) 180.0);
+ preMultiply(rot);
+ }
- if (axis == 'z')
+ /**
+ * Answers a matrix which, when it pre-multiplies another matrix, applies a
+ * rotation of the specified number of degrees around the specified axis
+ *
+ * @param degrees
+ * @param axis
+ * @return
+ * @see https://en.wikipedia.org/wiki/Rotation_matrix#Basic_rotations
+ */
+ protected static float[][] getRotation(float degrees, Axis axis)
+ {
+ Float floatValue = Float.valueOf(degrees);
+ if (cachedRotations.get(axis).containsKey(floatValue))
{
- rot[0][0] = (float) costheta;
-
- rot[0][1] = (float) -sintheta;
-
- rot[0][2] = (float) 0.0;
-
- rot[1][0] = (float) sintheta;
-
- rot[1][1] = (float) costheta;
-
- rot[1][2] = (float) 0.0;
-
- rot[2][0] = (float) 0.0;
-
- rot[2][1] = (float) 0.0;
-
- rot[2][2] = (float) 1.0;
-
- preMultiply(rot);
+ // System.out.println("getRotation from cache: " + (int) degrees);
+ return cachedRotations.get(axis).get(floatValue);
}
- if (axis == 'x')
- {
- rot[0][0] = (float) 1.0;
-
- rot[0][1] = (float) 0.0;
-
- rot[0][2] = (float) 0.0;
-
- rot[1][0] = (float) 0.0;
+ float costheta = (float) Math.cos(degrees * Math.PI / 180f);
- rot[1][1] = (float) costheta;
+ float sintheta = (float) Math.sin(degrees * Math.PI / 180f);
- rot[1][2] = (float) sintheta;
+ float[][] rot = new float[DIMS][DIMS];
- rot[2][0] = (float) 0.0;
-
- rot[2][1] = (float) -sintheta;
-
- rot[2][2] = (float) costheta;
-
- preMultiply(rot);
- }
-
- if (axis == 'y')
+ switch (axis)
{
- rot[0][0] = (float) costheta;
-
- rot[0][1] = (float) 0.0;
-
- rot[0][2] = (float) -sintheta;
-
- rot[1][0] = (float) 0.0;
-
- rot[1][1] = (float) 1.0;
-
- rot[1][2] = (float) 0.0;
-
- rot[2][0] = (float) sintheta;
-
- rot[2][1] = (float) 0.0;
-
- rot[2][2] = (float) costheta;
-
- preMultiply(rot);
+ case X:
+ rot[0][0] = 1f;
+ rot[1][1] = costheta;
+ rot[1][2] = sintheta;
+ rot[2][1] = -sintheta;
+ rot[2][2] = costheta;
+ break;
+ case Y:
+ rot[0][0] = costheta;
+ rot[0][2] = -sintheta;
+ rot[1][1] = 1f;
+ rot[2][0] = sintheta;
+ rot[2][2] = costheta;
+ break;
+ case Z:
+ rot[0][0] = costheta;
+ rot[0][1] = -sintheta;
+ rot[1][0] = sintheta;
+ rot[1][1] = costheta;
+ rot[2][2] = 1f;
+ break;
}
+ return rot;
}
/**
- * DOCUMENT ME!
+ * Answers a new array of float values which is the result of pre-multiplying
+ * this matrix by the given vector. Each value of the result is the dot
+ * product of the vector with one column of this matrix. The matrix and input
+ * vector are not modified.
*
* @param vect
- * DOCUMENT ME!
*
- * @return DOCUMENT ME!
+ * @return
*/
public float[] vectorMultiply(float[] vect)
{
- temp[0] = vect[0];
-
- temp[1] = vect[1];
-
- temp[2] = vect[2];
+ float[] result = new float[DIMS];
- for (int i = 0; i < 3; i++)
+ for (int i = 0; i < DIMS; i++)
{
- temp[i] = (matrix[i][0] * vect[0]) + (matrix[i][1] * vect[1])
+ result[i] = (matrix[i][0] * vect[0]) + (matrix[i][1] * vect[1])
+ (matrix[i][2] * vect[2]);
}
- vect[0] = temp[0];
-
- vect[1] = temp[1];
-
- vect[2] = temp[2];
-
- return vect;
+ return result;
}
/**
- * DOCUMENT ME!
+ * Performs pre-multiplication of this matrix by the given one. Value (i, j)
+ * of the result is the dot product of the i'th row of <code>mat</code> with
+ * the j'th column of this matrix.
*
* @param mat
- * DOCUMENT ME!
*/
public void preMultiply(float[][] mat)
{
- float[][] tmp = new float[3][3];
+ float[][] tmp = new float[DIMS][DIMS];
- for (int i = 0; i < 3; i++)
+ for (int i = 0; i < DIMS; i++)
{
- for (int j = 0; j < 3; j++)
+ for (int j = 0; j < DIMS; j++)
{
tmp[i][j] = (mat[i][0] * matrix[0][j]) + (mat[i][1] * matrix[1][j])
+ (mat[i][2] * matrix[2][j]);
}
}
- for (int i = 0; i < 3; i++)
- {
- for (int j = 0; j < 3; j++)
- {
- matrix[i][j] = tmp[i][j];
- }
- }
+ matrix = tmp;
}
/**
- * DOCUMENT ME!
+ * Performs post-multiplication of this matrix by the given one. Value (i, j)
+ * of the result is the dot product of the i'th row of this matrix with the
+ * j'th column of <code>mat</code>.
*
* @param mat
- * DOCUMENT ME!
*/
public void postMultiply(float[][] mat)
{
- float[][] tmp = new float[3][3];
+ float[][] tmp = new float[DIMS][DIMS];
- for (int i = 0; i < 3; i++)
+ for (int i = 0; i < DIMS; i++)
{
- for (int j = 0; j < 3; j++)
+ for (int j = 0; j < DIMS; j++)
{
tmp[i][j] = (matrix[i][0] * mat[0][j]) + (matrix[i][1] * mat[1][j])
+ (matrix[i][2] * mat[2][j]);
}
}
- for (int i = 0; i < 3; i++)
- {
- for (int j = 0; j < 3; j++)
- {
- matrix[i][j] = tmp[i][j];
- }
- }
+ matrix = tmp;
}
/**
*/
public static void main(String[] args)
{
- RotatableMatrix m = new RotatableMatrix(3, 3);
+ RotatableMatrix m = new RotatableMatrix();
- m.addElement(0, 0, 1);
+ m.setValue(0, 0, 1);
- m.addElement(0, 1, 0);
+ m.setValue(0, 1, 0);
- m.addElement(0, 2, 0);
+ m.setValue(0, 2, 0);
- m.addElement(1, 0, 0);
+ m.setValue(1, 0, 0);
- m.addElement(1, 1, 2);
+ m.setValue(1, 1, 2);
- m.addElement(1, 2, 0);
+ m.setValue(1, 2, 0);
- m.addElement(2, 0, 0);
+ m.setValue(2, 0, 0);
- m.addElement(2, 1, 0);
+ m.setValue(2, 1, 0);
- m.addElement(2, 2, 1);
+ m.setValue(2, 2, 1);
m.print();
- RotatableMatrix n = new RotatableMatrix(3, 3);
+ RotatableMatrix n = new RotatableMatrix();
- n.addElement(0, 0, 2);
+ n.setValue(0, 0, 2);
- n.addElement(0, 1, 1);
+ n.setValue(0, 1, 1);
- n.addElement(0, 2, 1);
+ n.setValue(0, 2, 1);
- n.addElement(1, 0, 2);
+ n.setValue(1, 0, 2);
- n.addElement(1, 1, 1);
+ n.setValue(1, 1, 1);
- n.addElement(1, 2, 1);
+ n.setValue(1, 2, 1);
- n.addElement(2, 0, 2);
+ n.setValue(2, 0, 2);
- n.addElement(2, 1, 1);
+ n.setValue(2, 1, 1);
- n.addElement(2, 2, 1);
+ n.setValue(2, 2, 1);
n.print();
}
/**
- * DOCUMENT ME!
+ * Performs a vector multiplication whose result is the Point representing the
+ * input point's value vector post-multiplied by this matrix.
+ *
+ * @param coord
+ * @return
*/
- public void setIdentity()
+ public Point vectorMultiply(Point coord)
{
- matrix[0][0] = (float) 1.0;
-
- matrix[1][1] = (float) 1.0;
-
- matrix[2][2] = (float) 1.0;
-
- matrix[0][1] = (float) 0.0;
-
- matrix[0][2] = (float) 0.0;
-
- matrix[1][0] = (float) 0.0;
-
- matrix[1][2] = (float) 0.0;
-
- matrix[2][0] = (float) 0.0;
-
- matrix[2][1] = (float) 0.0;
+ float[] v = vectorMultiply(new float[] { coord.x, coord.y, coord.z });
+ return new Point(v[0], v[1], v[2]);
}
}
git://source.jalview.org / jalview.git / blobdiff