package com.catsprogrammer.catsfourthv;

/**
 * Created by C on 2016-09-14.
 */
public class MatrixCalculator {


    public static float[] getRotationMatrixFromOrientation(float[] o) {
        float[] xM = new float[9];
        float[] yM = new float[9];
        float[] zM = new float[9];

        float sinX = (float) Math.sin(o[1]);
        float cosX = (float) Math.cos(o[1]);
        float sinY = (float) Math.sin(o[2]);
        float cosY = (float) Math.cos(o[2]);
        float sinZ = (float) Math.sin(o[0]);
        float cosZ = (float) Math.cos(o[0]);

        // rotation about x-axis (pitch)
        xM[0] = 1.0f;
        xM[1] = 0.0f;
        xM[2] = 0.0f;
        xM[3] = 0.0f;
        xM[4] = cosX;
        xM[5] = sinX;
        xM[6] = 0.0f;
        xM[7] = -sinX;
        xM[8] = cosX;

        // rotation about y-axis (roll)
        yM[0] = cosY;
        yM[1] = 0.0f;
        yM[2] = sinY;
        yM[3] = 0.0f;
        yM[4] = 1.0f;
        yM[5] = 0.0f;
        yM[6] = -sinY;
        yM[7] = 0.0f;
        yM[8] = cosY;

        // rotation about z-axis (azimuth)
        zM[0] = cosZ;
        zM[1] = sinZ;
        zM[2] = 0.0f;
        zM[3] = -sinZ;
        zM[4] = cosZ;
        zM[5] = 0.0f;
        zM[6] = 0.0f;
        zM[7] = 0.0f;
        zM[8] = 1.0f;

        // rotation order is y, x, z (roll, pitch, azimuth)
        float[] resultMatrix = matrixMultiplication(xM, yM);
        resultMatrix = matrixMultiplication(zM, resultMatrix); //????????????????왜?????????????
        return resultMatrix;
    }

    public static float[] matrixMultiplication(float[] A, float[] B) {
        float[] result = new float[9];

        result[0] = A[0] * B[0] + A[1] * B[3] + A[2] * B[6];
        result[1] = A[0] * B[1] + A[1] * B[4] + A[2] * B[7];
        result[2] = A[0] * B[2] + A[1] * B[5] + A[2] * B[8];

        result[3] = A[3] * B[0] + A[4] * B[3] + A[5] * B[6];
        result[4] = A[3] * B[1] + A[4] * B[4] + A[5] * B[7];
        result[5] = A[3] * B[2] + A[4] * B[5] + A[5] * B[8];

        result[6] = A[6] * B[0] + A[7] * B[3] + A[8] * B[6];
        result[7] = A[6] * B[1] + A[7] * B[4] + A[8] * B[7];
        result[8] = A[6] * B[2] + A[7] * B[5] + A[8] * B[8];

        return result;
    }


}
