diff --git a/__test__/Line/__snapshots__/line.test.ts.snap b/__test__/Line/__snapshots__/line.test.ts.snap
new file mode 100644
index 000000000..b1c9b38aa
--- /dev/null
+++ b/__test__/Line/__snapshots__/line.test.ts.snap
@@ -0,0 +1,17 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`直线偏移 1`] = `
+Vector3 {
+  "x": -6.123233995736766e-16,
+  "y": 10,
+  "z": 0,
+}
+`;
+
+exports[`直线偏移 2`] = `
+Vector3 {
+  "x": 4.999999999999999,
+  "y": 10,
+  "z": 0,
+}
+`;
diff --git a/__test__/Line/line.test.ts b/__test__/Line/line.test.ts
index d6f87c287..f7ecd3949 100644
--- a/__test__/Line/line.test.ts
+++ b/__test__/Line/line.test.ts
@@ -57,3 +57,38 @@ test("直线延伸-正向", () =>
     l.Extend(2);
     expect(l.EndPoint).toMatchObject({ 'x': 10, 'y': 0, 'z': 0 });
 });
+test("由距离得到直线参数", () =>
+{
+    let l = new Line(new Vector3(0, 0, 0), new Vector3(5, 0, 0));
+    expect(l.GetParamAtDist(10)).toBe(2);
+}
+);
+test("由距离得到对应点", () =>
+{
+    let l = new Line(new Vector3(0, 0, 0), new Vector3(5, 0, 0));
+    expect(l.GetPointAtDistance(-10)).toMatchObject({ "x": -10, 'y': 0, 'z': 0 });
+}
+);
+test("由参数得到距离", () =>
+{
+    let l = new Line(new Vector3(0, 0, 0), new Vector3(5, 0, 0));
+    expect(l.GetDistAtParam(-2)).toBe(-10);
+}
+);
+test("由点得到距离", () =>
+{
+    let l = new Line(new Vector3(0, 0, 0), new Vector3(5, 0, 0));
+    expect(l.GetDistAtPoint(new Vector3(-10, 0, 0))).toBe(-10);
+    expect(l.GetDistAtPoint(new Vector3(10, 0, 0))).toBe(10);
+}
+);
+test('直线偏移', () =>
+{
+    let l = new Line(new Vector3(0, 0, 0), new Vector3(5, 0, 0));
+    let lines = l.GetOffsetCurves(-10);
+    expect(lines.length).toBe(1);
+
+    let newLine = lines[0];
+    expect(newLine.StartPoint).toMatchSnapshot();
+    expect(newLine.EndPoint).toMatchSnapshot();
+});
diff --git a/src/DatabaseServices/Line.ts b/src/DatabaseServices/Line.ts
index 45b2a5807..89b484d5c 100644
--- a/src/DatabaseServices/Line.ts
+++ b/src/DatabaseServices/Line.ts
@@ -3,7 +3,7 @@ import { Geometry, Matrix4, Object3D, Vector3 } from 'three';
 import * as THREE from 'three';
 
 import { ColorMaterial } from '../Common/ColorPalette';
-import { equal } from '../Geometry/GeUtils';
+import { equal, polar } from '../Geometry/GeUtils';
 import { RenderType } from '../GraphicsSystem/Enum';
 import { Intersect, IntersectLineAndLine } from '../GraphicsSystem/IntersectWith';
 import { Factory } from './CADFactory';
@@ -101,9 +101,6 @@ export class Line extends Curve
     {
         return this.StartPoint.add(this.GetFistDeriv(0).multiplyScalar(param));
     }
-    GetPointAtDistance(distance: number): Vector3 { return; }
-    GetDistAtParam(param: number): number { return; }
-    GetDistAtPoint(pt: Vector3): number { return; }
     GetParamAtPoint(pt: Vector3): number
     {
         let len = this.Length;
@@ -128,7 +125,22 @@ export class Line extends Curve
         }
         return NaN;
     }
-    GetParamAtDist(d: number): number { return; }
+    GetParamAtDist(d: number): number
+    {
+        return d / this.Length;
+    }
+    GetPointAtDistance(distance: number): Vector3
+    {
+        return this.GetPointAtParam(this.GetParamAtDist(distance));
+    }
+    GetDistAtParam(param: number): number
+    {
+        return this.Length * param;
+    }
+    GetDistAtPoint(pt: Vector3): number
+    {
+        return this.GetDistAtParam(this.GetParamAtPoint(pt));
+    }
     PtOnCurve(pt: Vector3): boolean
     {
         let param = this.GetParamAtPoint(pt);
@@ -183,6 +195,16 @@ export class Line extends Curve
             this.EndPoint = this.GetPointAtParam(newParam);
         }
     }
+
+    GetOffsetCurves(offsetDist: number): Array<Curve> 
+    {
+        let an = this.GetFistDeriv(0).angleTo(new Vector3(1, 0, 0)) - Math.PI * 0.5;
+        let newLine = this.Clone() as Line;
+        newLine.StartPoint = polar(this.StartPoint, an, offsetDist);
+        newLine.EndPoint = polar(this.EndPoint, an, offsetDist);
+        return [newLine];
+    }
+
     get StartParam()
     {
         return 0;
diff --git a/src/Editor/CommandRegister.ts b/src/Editor/CommandRegister.ts
index 0bfc6a6fb..97187fbf5 100644
--- a/src/Editor/CommandRegister.ts
+++ b/src/Editor/CommandRegister.ts
@@ -1,38 +1,38 @@
 // import { Command_DrawBoard } from '../Add-on/DrawBoard';
 // import { DrawFloor } from '../Add-on/DrawFloor';
 import { DrawAxis } from '../Add-on/AddAxis';
+import { Command_Copy } from '../Add-on/Copy';
+import { CustomUcs } from '../Add-on/CostumUCS';
 import { Union } from '../Add-on/CSGUnion';
+import { DrawArc } from '../Add-on/DrawArc';
 import { DrawEllipse } from '../Add-on/DrawEllipse';
 import { DrawFloor } from '../Add-on/DrawFloor';
 import { DrawGripStretch } from '../Add-on/DrawGripStretch';
 import { DrawCircle, DrawLine, DrawRect, DrawSphere, DrawTest, ZoomE } from '../Add-on/DrawLine';
-import { DrawArc } from '../Add-on/DrawArc';
+import { DrawPolyline } from '../Add-on/DrawPolyline';
+import { DrawRegion } from '../Add-on/DrawRegion';
 import { DrawSky } from '../Add-on/DrawSky';
 import { DrawSpline } from '../Add-on/DrawSpline';
+import { DrawRegTest } from '../Add-on/DrawTestReg';
 import { DrawCircle0 } from '../Add-on/DrawZeroCircle';
 import { Entsel } from '../Add-on/Entsel';
 import { Command_Erase } from '../Add-on/Erase';
+import { Command_Extend } from '../Add-on/Extends';
 import { Fbx } from '../Add-on/loadfbx';
 import { LoadImg } from '../Add-on/LoadImg';
 import { Command_Move } from '../Add-on/Move';
 import { Open } from '../Add-on/Open';
+import { Command_RevPl } from '../Add-on/RevPl';
 import { Command_Rotate } from '../Add-on/Rotate';
 import { Save } from '../Add-on/Save';
 import { Stretch } from '../Add-on/Stretch';
 import { Command_SwitchCamera } from '../Add-on/SwitchCamera';
 import { Command_SwitchPass } from '../Add-on/SwitchPass';
 import { Test } from '../Add-on/test';
+import { Command_Trim } from '../Add-on/Trim';
 import { Redo, Undo } from '../Add-on/Undo';
 import { ViewToFront, ViewToTop } from '../Add-on/ViewChange';
 import { commandMachine } from './CommandMachine';
-import { DrawRegion } from '../Add-on/DrawRegion';
-import { DrawRegTest } from '../Add-on/DrawTestReg';
-import { DrawPolyline } from '../Add-on/DrawPolyline';
-import { CustomUcs } from '../Add-on/CostumUCS';
-import { Command_Copy } from '../Add-on/Copy';
-import { Command_RevPl } from '../Add-on/RevPl';
-import { Command_Extend } from '../Add-on/Extends';
-import { Command_Trim } from '../Add-on/Trim';
 
 // import { RevTarget, SaveTarget } from '../Add-on/RenderTarget';
 export function registerCommand()