diff --git a/__test__/Line/__snapshots__/line.test.ts.snap b/__test__/Line/__snapshots__/line.test.ts.snap
index fd9848f65..17e859673 100644
--- a/__test__/Line/__snapshots__/line.test.ts.snap
+++ b/__test__/Line/__snapshots__/line.test.ts.snap
@@ -50,7 +50,7 @@ Vector3 {
 
 exports[`直线偏移 1`] = `
 Vector3 {
-  "x": -6.123233995736766e-16,
+  "x": 0,
   "y": 10,
   "z": 0,
 }
@@ -58,7 +58,7 @@ Vector3 {
 
 exports[`直线偏移 2`] = `
 Vector3 {
-  "x": 4.999999999999999,
+  "x": 5,
   "y": 10,
   "z": 0,
 }
diff --git a/__test__/Room/__snapshots__/RoomParse.test.ts.snap b/__test__/Room/__snapshots__/RoomParse.test.ts.snap
index 50d36372d..418c147c4 100644
--- a/__test__/Room/__snapshots__/RoomParse.test.ts.snap
+++ b/__test__/Room/__snapshots__/RoomParse.test.ts.snap
@@ -369,7 +369,7 @@ Array [
 exports[`圆弧合集 8`] = `
 Array [
   0,
-  390.90041837162016,
+  390.9004183716206,
   0,
 ]
 `;
@@ -408,8 +408,8 @@ Array [
 
 exports[`圆弧合集 13`] = `
 Array [
-  -0.8112557813765306,
-  -20.020800824495154,
+  -0.8112557813756212,
+  -20.0208008244947,
   0,
 ]
 `;
@@ -417,7 +417,7 @@ Array [
 exports[`圆弧合集 14`] = `
 Array [
   -890.6332403472697,
-  901.9543177434239,
+  901.9543177434243,
   0,
 ]
 `;
@@ -425,15 +425,15 @@ Array [
 exports[`圆弧合集 15`] = `
 Array [
   -838.0308338264754,
-  848.6832679602089,
+  848.6832679602094,
   0,
 ]
 `;
 
 exports[`圆弧合集 16`] = `
 Array [
-  3.020815205217332,
-  2.982898780776395,
+  3.020815205215513,
+  2.982898780775031,
   0,
 ]
 `;
@@ -1601,7 +1601,7 @@ Array [
 exports[`测试重叠墙裁剪共面墙 11`] = `
 Array [
   95.73217955431755,
-  72.35571710500767,
+  72.35571710500722,
   0,
 ]
 `;
@@ -1744,23 +1744,23 @@ Array [
 
 exports[`直线与圆弧 1`] = `
 Array [
-  1729.7058390528305,
-  -484.8814639276738,
+  1729.705839052831,
+  -484.8814639276739,
   0,
 ]
 `;
 
 exports[`直线与圆弧 2`] = `
 Array [
-  1228.2620544368035,
-  -344.3137495380443,
+  1228.262054436803,
+  -344.3137495380442,
   0,
 ]
 `;
 
 exports[`直线与圆弧 3`] = `
 Array [
-  -32.39051566134185,
+  -32.39051566134094,
   -115.54589778608533,
   0,
 ]
diff --git a/src/Common/CurveUtils.ts b/src/Common/CurveUtils.ts
index ac31f627a..3f693e914 100644
--- a/src/Common/CurveUtils.ts
+++ b/src/Common/CurveUtils.ts
@@ -280,13 +280,14 @@ export function GetPointAtCurveDir(cu: Curve, pt: Vector3): number
     }
     else if (cu instanceof Spline)
         return GetPointAtCurveDir(cu.Convert2Polyline(), pt);
+
     //最近点
     let cp = cu.GetClosestPointTo(pt, false);
     if (equalv3(cp, pt, 1e-6)) return 0;
-    //最近点参数
-    let cparam = cu.GetParamAtPoint(cp);
-    let dri = cu.GetFistDeriv(cparam);
-    let cross = dri.cross(pt.clone().sub(cp)).applyMatrix4(cu.OCSInv);
+    //最近点的切线
+    let deriv = cu.GetFistDeriv(cu.GetParamAtPoint(cp));
+    let vec2 = pt.clone().sub(cp);
+    let cross = deriv.cross(vec2).applyMatrix4(cu.OCSInv.setPosition(0, 0, 0));
     return -Math.sign(cross.z);
 }
 
diff --git a/src/DatabaseServices/Entity/Line.ts b/src/DatabaseServices/Entity/Line.ts
index e4e22623c..fd1fed368 100644
--- a/src/DatabaseServices/Entity/Line.ts
+++ b/src/DatabaseServices/Entity/Line.ts
@@ -9,6 +9,7 @@ import { Box3Ext } from '../../Geometry/Box';
 import { BufferGeometryUtils } from '../../Geometry/BufferGeometryUtils';
 import { AsVector2, equaln, equalv3, isParallelTo, MoveMatrix, updateGeometry } from '../../Geometry/GeUtils';
 import { PlaneExt } from '../../Geometry/Plane';
+import { ROTATE_MTX2 } from '../../Geometry/RotateUV';
 import { IntersectEllipseAndLine, IntersectLineAndArc, IntersectLineAndCircle, IntersectLineAndLine, IntersectOption, IntersectPolylineAndCurve, IntersectResult, reverseIntersectOption } from '../../GraphicsSystem/IntersectWith';
 import { RenderType } from '../../GraphicsSystem/RenderType';
 import { Factory } from '../CADFactory';
@@ -403,13 +404,12 @@ export class Line extends Curve
 
     GetOffsetCurves(offsetDist: number): Array<Curve>
     {
-        let derv = this.GetFistDeriv(0).normalize().multiplyScalar(offsetDist);
-        derv.applyMatrix4(new Matrix4().makeRotationAxis(this.Normal, -Math.PI / 2));
+        let offset = this._EndPoint.clone().sub(this._StartPoint).normalize().multiplyScalar(offsetDist);
+        ROTATE_MTX2.applyVector(offset);
         let newLine = this.Clone() as Line;
-        newLine.SetStartEndPoint(
-            this.StartPoint.add(derv),
-            this.EndPoint.add(derv)
-        );
+        newLine.ClearDraw();
+        newLine._StartPoint.add(offset);
+        newLine._EndPoint.add(offset);
         return [newLine];
     }