20 lines
488 B
TypeScript
20 lines
488 B
TypeScript
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class Vector2Ext {
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/**
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* 检查三角形是CCW还是CW
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* @param a
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* @param center
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* @param c
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*/
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public static isTriangleCCW(a: Vector2, center: Vector2, c: Vector2){
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return this.cross(Vector2.subtract(center, a), Vector2.subtract(c, center)) < 0;
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}
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/**
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* 计算二维伪叉乘点(Perp(u)， v)
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* @param u
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* @param v
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*/
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public static cross(u: Vector2, v: Vector2){
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return u.y * v.x - u.x * v.y;
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}
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}
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