77 lines
1.7 KiB
JavaScript
77 lines
1.7 KiB
JavaScript
class TransformMatrix {
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constructor() {
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this.reset();
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}
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reset() {
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this.a = 1; // 水平缩放
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this.b = 0; // 垂直倾斜
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this.c = 0; // 水平倾斜
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this.d = 1; // 垂直缩放
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this.tx = 0; // 水平移动
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this.ty = 0; // 垂直移动
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this.stack = [];
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}
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translate(dx, dy) {
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this.tx += this.a * dx + this.c * dy;
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this.ty += this.b * dx + this.d * dy;
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}
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scale(sx, sy, cx = 0, cy = 0) {
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// 移动到中心点
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this.translate(cx, cy);
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// 应用缩放
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this.a *= sx;
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this.b *= sx;
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this.c *= sy;
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this.d *= sy;
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// 移回原位置
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this.translate(-cx, -cy);
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}
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toArray() {
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return [this.a, this.b, this.c, this.d, this.tx, this.ty];
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}
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// 用于调试的字符串表示
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toString() {
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return `[${this.a.toFixed(2)}, ${this.b.toFixed(2)}, ${this.c.toFixed(2)}, ${this.d.toFixed(2)}, ${this.tx.toFixed(1)}, ${this.ty.toFixed(1)}]`;
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}
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// 克隆方法
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clone() {
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const clone = new TransformMatrix();
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clone.a = this.a;
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clone.b = this.b;
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clone.c = this.c;
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clone.d = this.d;
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clone.tx = this.tx;
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clone.ty = this.ty;
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return clone;
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}
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// 添加点坐标转换方法
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transformPoint(x, y) {
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return {
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x: this.a * x + this.c * y + this.tx,
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y: this.b * x + this.d * y + this.ty
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};
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}
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// 添加逆矩阵转换方法
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invertPoint(x, y, dpr) {
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console.log('invertPoint：',dpr)
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const det = this.a * this.d - this.b * this.c;
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if (Math.abs(det) < 0.0001) return {x, y};
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return {
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x: (this.d * (x/dpr - this.tx) - this.c * (y/dpr - this.ty)) / det,
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y: (this.a * (y/dpr - this.ty) - this.b * (x/dpr - this.tx)) / det
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};
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}
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}
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export default TransformMatrix; |