src/services/MatrixService.java - main - vanwise/java_multidimensional_arrays

src/services/MatrixService.java
71 строка2 KB
Ivan Zhukov
feat: add grayscale matrix rotation
19 сен 2025, 21:41
19 сен 2025, 21:416ee34f9
package services;

import java.util.Random;

public class MatrixService {
    public static final int ANGLE_90 = 90;
    public static final int ANGLE_180 = 180;
    public static final int ANGLE_270 = 270;

    public static final int GRAY_SCALE_SIZE = 8;
    public static final int GRAY_SCALE_MAX_VALUE = 256;

    public static void print(int[][] matrix) {
        for (int[] ints : matrix) {
            for (int j = 0; j < matrix.length; j++) {
                System.out.format("%4d", ints[j]);
            }
            System.out.println();
        }

        System.out.println();
    }

    public static int[][] rotate(int[][] matrix, int angle) {
        int matrixMaxIndex = matrix.length - 1;
        int[][] rotatedMatrix = new int[matrix.length][matrix.length];

        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix.length; j++) {
                int[] coordinates = getShiftedCoordinatesByAngle(i, j, matrixMaxIndex, angle);
                rotatedMatrix[coordinates[0]][coordinates[1]] = matrix[i][j];
            }
        }

        return rotatedMatrix;
    }

    private static int[] getShiftedCoordinatesByAngle(int xIndex, int yIndex, int matrixMaxIndex, int angle) {
        int[] coordinates = new int[2];

        switch (angle) {
            case ANGLE_90:
                coordinates[0] = yIndex;
                coordinates[1] = matrixMaxIndex - xIndex;
                break;
            case ANGLE_180:
                coordinates[0] = matrixMaxIndex - xIndex;
                coordinates[1] = matrixMaxIndex - yIndex;
                break;
            case ANGLE_270:
                coordinates[0] = matrixMaxIndex - yIndex;
                coordinates[1] = xIndex;
                break;
        }

        return coordinates;
    }

    public static int[][] createRandomGrayScale() {
        Random random = new Random();
        int[][] matrix = new int[GRAY_SCALE_SIZE][GRAY_SCALE_SIZE];

        for (int i = 0; i < GRAY_SCALE_SIZE; i++) {
            for (int j = 0; j < GRAY_SCALE_SIZE; j++) {
                matrix[i][j] = random.nextInt(GRAY_SCALE_MAX_VALUE);
            }
        }

        return matrix;
    }
}