核心提示：THREE.Euler用法 THREE.Euler( a , b , c , xyz );表示将一个几何体绕x轴旋转a度，绕y轴旋转b度，绕z轴旋转c度；并且旋转的顺序是xyz ; 第三个参数旋转顺序...
THREE.Euler
用法 THREE.Euler( a , b , c , ‘xyz’ );
表示将一个几何体绕x轴旋转a度，绕y轴旋转b度，绕z轴旋转c度；并且旋转的顺序是xyz ; 第三个参数旋转顺序可以是’XYZ’, ‘YZX’, ‘ZXY’, ‘XZY’, ‘YXZ’, ‘ZYX’
THREE.Euler = function ( x, y, z, order ) {
this._x = x || 0;
this._y = y || 0;
this._z = z || 0;
this._order = order || THREE.Euler.DefaultOrder;
};
原型上的方法
set( x , y , z , order )
set: function ( x, y, z, order ) {
this._x = x;
this._y = y;
this._z = z;
this._order = order || this._order;
this.onChangeCallback(); //调用回调函数.
return this; //返回新的Euler(欧拉角)
},
setFromRotationMatrix
setFromRotationMatrix: function ( m, order ) {
var clamp = THREE.Math.clamp; //clamp用来设置数值的取值范围
// assumes the upper 3x3 of m is a pure rotation matrix (i.e, unscaled)
// 确保参数m是一个3x3的旋转矩阵.
var te = m.elements;
var m11 = te[ 0 ], m12 = te[ 4 ], m13 = te[ 8 ];
var m21 = te[ 1 ], m22 = te[ 5 ], m23 = te[ 9 ];
var m31 = te[ 2 ], m32 = te[ 6 ], m33 = te[ 10 ];
order = order || this._order;
if ( order === 'XYZ' ) {
this._y = Math.asin( clamp( m13, - 1, 1 ) );
if ( Math.abs( m13 ) < 0.99999 ) {
this._x = Math.atan2( - m23, m33 );
this._z = Math.atan2( - m12, m11 );
} else {
this._x = Math.atan2( m32, m22 );
this._z = 0;
}
} else if ( order === 'YXZ' ) {
this._x = Math.asin( - clamp( m23, - 1, 1 ) );
if ( Math.abs( m23 ) < 0.99999 ) {
this._y = Math.atan2( m13, m33 );
this._z = Math.atan2( m21, m22 );
} else {
this._y = Math.atan2( - m31, m11 );
this._z = 0;
}
} else if ( order === 'ZXY' ) {
this._x = Math.asin( clamp( m32, - 1, 1 ) );
if ( Math.abs( m32 ) < 0.99999 ) {
this._y = Math.atan2( - m31, m33 );
this._z = Math.atan2( - m12, m22 );
} else {
this._y = 0;
this._z = Math.atan2( m21, m11 );
}
} else if ( order === 'ZYX' ) {
this._y = Math.asin( - clamp( m31, - 1, 1 ) );
if ( Math.abs( m31 ) < 0.99999 ) {
this._x = Math.atan2( m32, m33 );
this._z = Math.atan2( m21, m11 );
} else {
this._x = 0;
this._z = Math.atan2( - m12, m22 );
}
} else if ( order === 'YZX' ) {
this._z = Math.asin( clamp( m21, - 1, 1 ) );
if ( Math.abs( m21 ) < 0.99999 ) {
this._x = Math.atan2( - m23, m22 );
this._y = Math.atan2( - m31, m11 );
} else {
this._x = 0;
this._y = Math.atan2( m13, m33 );
}
} else if ( order === 'XZY' ) {
this._z = Math.asin( - clamp( m12, - 1, 1 ) );
if ( Math.abs( m12 ) < 0.99999 ) {
this._x = Math.atan2( m32, m22 );
this._y = Math.atan2( m13, m11 );
} else {
this._x = Math.atan2( - m23, m33 );
this._y = 0;
}
} else {
console.warn( 'THREE.Euler: .setFromRotationMatrix() given unsupported order: ' + order ) //通过按照以上几种旋转顺序设置欧拉角对象失败报错
}
this._order = order; //重新设置旋转顺序
this.onChangeCallback(); //调用回调函数.
return this; //返回新的Euler(欧拉角)
},
