| /* Utils.java -- A collection of utility functions for the autofitter |
| Copyright (C) 2006 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath 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 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package gnu.java.awt.font.autofit; |
| |
| import gnu.java.awt.font.opentype.truetype.Fixed; |
| |
| /** |
| * A collection of utility methods used all around the auto fitter. |
| */ |
| class Utils |
| implements Constants |
| { |
| |
| private static final int ATAN_BITS = 8; |
| private static final byte[] ATAN = new byte[] |
| { |
| 0, 0, 1, 1, 1, 2, 2, 2, |
| 3, 3, 3, 3, 4, 4, 4, 5, |
| 5, 5, 6, 6, 6, 7, 7, 7, |
| 8, 8, 8, 9, 9, 9, 10, 10, |
| 10, 10, 11, 11, 11, 12, 12, 12, |
| 13, 13, 13, 14, 14, 14, 14, 15, |
| 15, 15, 16, 16, 16, 17, 17, 17, |
| 18, 18, 18, 18, 19, 19, 19, 20, |
| 20, 20, 21, 21, 21, 21, 22, 22, |
| 22, 23, 23, 23, 24, 24, 24, 24, |
| 25, 25, 25, 26, 26, 26, 26, 27, |
| 27, 27, 28, 28, 28, 28, 29, 29, |
| 29, 30, 30, 30, 30, 31, 31, 31, |
| 31, 32, 32, 32, 33, 33, 33, 33, |
| 34, 34, 34, 34, 35, 35, 35, 35, |
| 36, 36, 36, 36, 37, 37, 37, 38, |
| 38, 38, 38, 39, 39, 39, 39, 40, |
| 40, 40, 40, 41, 41, 41, 41, 42, |
| 42, 42, 42, 42, 43, 43, 43, 43, |
| 44, 44, 44, 44, 45, 45, 45, 45, |
| 46, 46, 46, 46, 46, 47, 47, 47, |
| 47, 48, 48, 48, 48, 48, 49, 49, |
| 49, 49, 50, 50, 50, 50, 50, 51, |
| 51, 51, 51, 51, 52, 52, 52, 52, |
| 52, 53, 53, 53, 53, 53, 54, 54, |
| 54, 54, 54, 55, 55, 55, 55, 55, |
| 56, 56, 56, 56, 56, 57, 57, 57, |
| 57, 57, 57, 58, 58, 58, 58, 58, |
| 59, 59, 59, 59, 59, 59, 60, 60, |
| 60, 60, 60, 61, 61, 61, 61, 61, |
| 61, 62, 62, 62, 62, 62, 62, 63, |
| 63, 63, 63, 63, 63, 64, 64, 64 |
| }; |
| |
| private static final int ANGLE_PI = 256; |
| private static final int ANGLE_PI2 = ANGLE_PI / 2; |
| private static final int ANGLE_PI4 = ANGLE_PI / 4; |
| private static final int ANGLE_2PI = ANGLE_PI * 2; |
| |
| /** |
| * Computes the direction constant for the specified vector. The vector is |
| * given as differential value already. |
| * |
| * @param dx the x vector |
| * @param dy the y vector |
| * |
| * @return the direction of that vector, or DIR_NONE, if that vector is not |
| * approximating against one of the major axises |
| */ |
| static int computeDirection(int dx, int dy) |
| { |
| int dir = DIR_NONE; |
| if (dx < 0) |
| { |
| if (dy < 0) |
| { |
| if (-dx * 12 < -dy) |
| dir = DIR_UP; |
| else if (-dy * 12 < -dx) |
| dir = DIR_LEFT; |
| } |
| else // dy >= 0 . |
| { |
| if (-dx * 12 < dy) |
| dir = DIR_DOWN; |
| else if (dy * 12 < -dx) |
| dir = DIR_LEFT; |
| } |
| } |
| else // dx >= 0 . |
| { |
| if (dy < 0) |
| { |
| if (dx * 12 < -dy) |
| dir = DIR_UP; |
| else if (-dy * 12 < dx) |
| dir = DIR_RIGHT; |
| } |
| else // dy >= 0 . |
| { |
| if (dx * 12 < dy) |
| dir = DIR_DOWN; |
| else if (dy * 12 < dx) |
| dir = DIR_RIGHT; |
| } |
| } |
| return dir; |
| } |
| |
| public static int atan(int dx, int dy) |
| { |
| int angle; |
| // Trivial cases. |
| if (dy == 0) |
| { |
| angle = 0; |
| if (dx < 0) |
| angle = ANGLE_PI; |
| return angle; |
| } |
| else if (dx == 0) |
| { |
| angle = ANGLE_PI2; |
| if (dy < 0) |
| angle = - ANGLE_PI2; |
| return angle; |
| } |
| |
| |
| angle = 0; |
| if (dx < 0) |
| { |
| dx = -dx; |
| dy = -dy; |
| angle = ANGLE_PI; |
| } |
| if (dy < 0) |
| { |
| int tmp = dx; |
| dx = -dy; |
| dy = tmp; |
| angle -= ANGLE_PI2; |
| } |
| if (dx == 0 && dy == 0) |
| return 0; |
| |
| if (dx == dy) |
| angle += ANGLE_PI4; |
| else if (dx > dy) |
| { |
| angle += ATAN[Fixed.div(dy, dx) << (ATAN_BITS - 6)]; |
| } |
| else |
| { |
| angle += ANGLE_PI2 - ATAN[Fixed.div(dx, dy) << (ATAN_BITS - 6)]; |
| } |
| |
| if (angle > ANGLE_PI) |
| angle -= ANGLE_2PI; |
| return angle; |
| } |
| |
| public static int angleDiff(int ang1, int ang2) |
| { |
| int delta = ang2 - ang1; |
| delta %= ANGLE_2PI; |
| if (delta < 0) |
| delta += ANGLE_2PI; |
| if (delta > ANGLE_PI) |
| delta -= ANGLE_2PI; |
| return delta; |
| } |
| |
| static void sort(int num, int[] array) |
| { |
| int swap; |
| for (int i = 1; i < num; i++) |
| { |
| for (int j = i; j > 0; j--) |
| { |
| if (array[j] > array[j - 1]) |
| break; |
| swap = array[j]; |
| array[j] = array[j - 1]; |
| array[j - 1] = swap; |
| } |
| } |
| } |
| |
| static void sort(int num, Width[] array) |
| { |
| Width swap; |
| for (int i = 1; i < num; i++) |
| { |
| for (int j = 1; j > 0; j--) |
| { |
| if (array[j].org > array[j - 1].org) |
| break; |
| swap = array[j]; |
| array[j] = array[j - 1]; |
| array[j - 1] = swap; |
| } |
| } |
| } |
| |
| static int pixRound(int val) |
| { |
| return pixFloor(val + 32); |
| } |
| |
| static int pixFloor(int val) |
| { |
| return val & ~63; |
| } |
| |
| public static int mulDiv(int a, int b, int c) |
| { |
| long prod = a * b; |
| long div = (prod / c); |
| return (int) div; |
| } |
| |
| } |