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SYS_Math.scale() method

Scale the polygon

Signature

function scale(
	polygon: TSYS_MathPolygonInput,
	scaleX: number,
	scaleY?: number,
	centerX?: number,
	centerY?: number,
): Array<ISYS_MathPoint>;

Parameters

Parameter	Type	Description
polygon	TSYS_MathPolygonInput	Polygon
scaleX	number	X direction scale ratio
scaleY	number	(Optional) Y direction scale ratio, defaulting to the same as scaleX
centerX	number	(Optional) X coordinate of the scaling center, defaulting to the centroid
centerY	number	(Optional) Y coordinate of the scaling center, defaulting to the centroid

Returns

Array<ISYS_MathPoint>

Array of discrete points after scaling

Example

// 1. 定义一个矩形焊区
const pad = [{ x: 0, y: 0 }, { x: 100, y: 0 }, { x: 100, y: 80 }, { x: 0, y: 80 }];

// 2. 等比放大 1.5 倍：绕质心原地放大，面积变为 2.25 倍
const enlarged = eda.sys_Math.scale(pad, 1.5);
console.log('放大 1.5 倍后的顶点：', JSON.stringify(enlarged));
console.log('放大后的面积：', eda.sys_Math.calculateArea(enlarged));

// 3. X、Y 采用不同比例：只在 X 方向拉宽 2 倍（绕质心，Y 不变）
const stretched = eda.sys_Math.scale(pad, 2, 1);
console.log('仅 X 方向放大 2 倍后的顶点：', JSON.stringify(stretched));

// 4. 指定缩放中心 (0, 0)：各点坐标直接乘以比例
const fromOrigin = eda.sys_Math.scale(pad, 2, 2, 0, 0);
console.log('绕原点放大后的第一个点：', JSON.stringify(fromOrigin[0]));