// code by JernejL
// transforms a vector using a 4x4 matrix (translation and scaling is ignored, only 3x3 part is used, we only need rotation!)
stock MatrixTransformVector(Float:vector[3], Float:m[4][4], &Float:resx, &Float:resy, &Float:resz) {
    resz = vector[2] * m[0][0] + vector[1] * m[0][1] + vector[0] * m[0][2] + m[0][3];
    resy = vector[2] * m[1][0] + vector[1] * m[1][1] + vector[0] * m[1][2] + m[1][3];
    resx = -(vector[2] * m[2][0] + vector[1] * m[2][1] + vector[0] * m[2][2] + m[2][3]); // don't ask why -x was needed, i don't know either.
}

// something for 0.3b
stock RotatePointVehicleRotation(vehid, Float:Invector[3], &Float:resx, &Float:resy, &Float:resz, worldspace=0) {

    new Float:Quaternion[4];
    new Float:transformationmatrix[4][4];

    GetVehicleRotationQuat(vehid, Quaternion[0], Quaternion[1], Quaternion[2], Quaternion[3]);

    // build a transformation matrix out of the quaternion
    new Float:xx = Quaternion[0] * Quaternion[0];
    new Float:xy = Quaternion[0] * Quaternion[1];
    new Float:xz = Quaternion[0] * Quaternion[2];
    new Float:xw = Quaternion[0] * Quaternion[3];
    new Float:yy = Quaternion[1] * Quaternion[1];
    new Float:yz = Quaternion[1] * Quaternion[2];
    new Float:yw = Quaternion[1] * Quaternion[3];
    new Float:zz = Quaternion[2] * Quaternion[2];
    new Float:zw = Quaternion[2] * Quaternion[3];

    transformationmatrix[0][0] = 1 - 2 * ( yy + zz );
    transformationmatrix[0][1] =     2 * ( xy - zw );
    transformationmatrix[0][2] =     2 * ( xz + yw );
    transformationmatrix[0][3] = 0.0;

    transformationmatrix[1][0] =     2 * ( xy + zw );
    transformationmatrix[1][1] = 1 - 2 * ( xx + zz );
    transformationmatrix[1][2] =     2 * ( yz - xw );
    transformationmatrix[1][3] = 0.0;

    transformationmatrix[2][0] =     2 * ( xz - yw );
    transformationmatrix[2][1] =     2 * ( yz + xw );
    transformationmatrix[2][2] = 1 - 2 * ( xx + yy );
    transformationmatrix[2][3] = 0;

    transformationmatrix[3][0] = 0;
    transformationmatrix[3][1] = 0;
    transformationmatrix[3][2] = 0;
    transformationmatrix[3][3] = 1;

    // transform the point thru car's rotation
    MatrixTransformVector(Invector, transformationmatrix, resx, resy, resz);

    // if worldspace is set it'll return the coords in global space - useful to check tire coords against tire spike proximity directly, etc..

    if (worldspace == 1) {
        new Float:fX, Float:fY, Float:fZ;
        GetVehiclePos(vehid, fX, fY, fZ);
        resx += fX;
        resy += fY;
        resz += fZ;
    }
}