C++实现坡度编辑命令，指定基点的情况下提示用户拾取一个点。
主要思路是：
- 先画一个坡度块。
- 绘制参考线，参考线能够进行极轴跟踪。
- 坡度编辑，选中坡度块，画出参考线，根据参考线延伸坡度长度。
图例如下：
示例如下：
-
程序入口点代码
```c++
//zhaoanan 坡度绘制
// - zndraw_thslope command (do not rename)
//自定义实体绘制坡度
static void zndraw_thslope(void)
{
AcDbDatabase m_pDb = acdbHostApplicationServices()->workingDatabase();
//添加块定义
acutPrintf(_T("\n坡度绘制")) ;
CUserSystem mysys = new CUserSystem();
mysys->m_pDb = m_pDb;
//声明左边插入点
ads_point pt_insert;
AcGePoint3d pt_3d_insert;
int iOldOsMode = 0 ;
BOOL bReturn = false ;
while (bReturn == false)
{
int iReturn = acedGetPoint(NULL,_T("\n 指定坡度的插入点："),pt_insert) ;
//int iReturn = acedEntSel(_T("\n选择实体对象"), en, pt) ;if(iReturn == RTNORM) { bReturn = true ; pt_3d_insert =asPnt3d(pt_insert); acutPrintf(_T("\n坡度插入点坐标：x坐标为：%f，y坐标为：%f"), pt_3d_insert.x, pt_3d_insert.y); //实例化轨道坡度对象 CthRailSlope *cthRailSlope = new CthRailSlope(); //指定坡度位置为插入点坐标 cthRailSlope->setPosition(pt_3d_insert); //添加坡度组件 CthComponent *lineCp = new CthComponent(); //thComponent c = new thComponent(); //根据插入点，画坡度上面的横线 lineCp->addLine(AcGePoint3d(-26, 7.5, 0), AcGePoint3d(0, 7.5, 0)); //根据插入点，画坡度下面的横线 lineCp->addLine(AcGePoint3d(-26, -7.5, 0), AcGePoint3d(0, -7.5, 0)); //以插入点横坐标X=-26为基准向上和向下画竖线 lineCp->addLine(AcGePoint3d(-26, 7.5, 0), AcGePoint3d(-26, -7.5, 0)); //添加坡度框体中间的文字 CthText *text = lineCp->addText(_T("坡"), AcGeVector3d(-23, 2.5, 0), 3); //指定字体对齐方式 text->setAlign(AcDbMText::kMiddleCenter); text = lineCp->addText(_T("度"), AcGeVector3d(-23, -2.5, 0), 3); //指定字体对齐方式 text->setAlign(AcDbMText::kMiddleCenter); //以插入点横坐标X=-20为基准向上和向下画竖线 lineCp->addLine(AcGePoint3d(-20, 7.5, 0), AcGePoint3d(-20, -7.5, 0)); //将新建的组件添加到坡度对象 cthRailSlope->appendComponent(lineCp); lineCp = new CthComponent(); //type=1, 没查到代表什么 lineCp->setType(1); //根据插入点，以插入点为基准向上和向下画竖线 lineCp->addLine(AcGePoint3d(pt_3d_insert.x, pt_3d_insert.y + 7.5, 0), AcGePoint3d(pt_3d_insert.x, pt_3d_insert.y - 7.5, 0)); //给新加的竖线添加文字 text = lineCp->addText(_T(""), AcGeVector3d(pt_3d_insert.x, pt_3d_insert.y, 0), 2.5); text->setName(_T("里程")); //指定字体旋转角度 text->setRotation(PI / 2); //指定字体对齐方式 text->setAlign(AcDbMText::kBottomCenter); //将新建的组件添加到坡度对象 cthRailSlope->appendComponent(lineCp); //获取devices.xml中的图层信息，给新建坡度对象添加图层 DTDevice* device = CZnUtility::GetDevice(cthRailSlope); //如果获取的devices.xml中的坡度相关图层信息不为空 if(device != nullptr && (!device->GetLayer().IsEmpty())) { //将图层信息添加到图层表中 if (addLayer(device)) { //如果图层信息添加到图层表成功，那么将图层信息赋值给当前坡度图层 cthRailSlope->setLayer(device->GetLayer()); } } //将里程实体加入到块表记录中 //cthRailSlope->AddRailSlope("ZDK1+222.45", "ZDK2+123.11", "20", 20.00, "30", cthRailSlope->position().x + 20, cthRailSlope->position().x + 50, 1); AcDbObjectId dimensionId = CDwgDatabaseUtil::PostToModelSpace(cthRailSlope, m_pDb); } else if (iReturn == RTERROR) { bReturn = false ; } else if (iReturn == RTCAN) { bReturn = true ; }}
//保存当前图层，设置要绘制的图层
AcDbObjectId ojbIdLayerOld = m_pDb->clayer() ;m_pDb->setClayer(ojbIdLayerOld) ; //恢复当前图层
} -
拖拽程序代码，要有坡度编辑的时候有参照线，指定基点的情况下提示用户拾取一个点，代码实现：
```c++
//刷新窗口 当即生效
int CGetInputUtil::GetPointReturnCode(const AcGePoint3d &basePoint, const TCHAR* prompt, AcGePoint3d &point)
{
//将基点转换为UCS坐标
AcGePoint3d ucsBasePoint = CConvertUtil::WcsToUcsPoint(basePoint);int nReturn = acedGetPoint(asDblArray(ucsBasePoint), prompt, asDblArray(point));
if (nReturn == RTNORM)
{
//acedGetPoint得到UCS坐标，转换为WCS
point = CConvertUtil::UcsToWcsPoint(point);
}return nReturn;
} -
坡度编辑代码
```c++
//zhaoanan 坡度编辑
// - zndraw_thslope command (do not rename)
//自定义实体坡度编辑
static void zndraw_thslopeedit(void)
{
AcDbDatabase m_pDb = acdbHostApplicationServices()->workingDatabase();
//添加块定义
acutPrintf(_T("\n坡度编辑")) ;
CUserSystem mysys = new CUserSystem();
mysys->m_pDb = m_pDb;//声明左边插入点
ads_name en ;
ads_point pt ;
BOOL bReturn = false ;
while (bReturn == false)
{
int iReturn = acedEntSel(_T("\n选择坡度实体对象"), en, pt) ;if(iReturn == RTNORM) { bReturn = true ; AcDbEntity * pEnt = NULL ; CthRailSlope * pthEnt = NULL; if(mysys->OpenAcDbEntity(en, pEnt, AcDb::kForRead)) { acedUpdateDisplay(); //指定坡度端点 if(pEnt->isKindOf(CthRailSlope::desc())) { pthEnt = CthRailSlope::cast(pEnt) ; pthEnt->upgradeOpen(); //获取里程值 CthComponent *pCpnt = pthEnt->getComponent(pthEnt->getComponentCount() - 1); CthLine* line= (CthLine*)pCpnt->getElement(0); AcGePoint3d pt_3d_base(line->startPoint().x, pthEnt->position().y, 0); // 左里程 CString m_left_kmpost = ""; //进行非空判断，可能为空，没有添加过左公里标时为空 if (pCpnt != NULL) { CthElement *pElm = pCpnt->getElement(_T("里程")); if (pElm->type() == 32) { CthText* pText = (CthText*)pElm; //更新里程值内容 m_left_kmpost = pText->textString(); } } //acutPrintf(_T("\n坡度基准点坐标：x坐标为：%f，y坐标为：%f"), pt_3d_base.x, pt_3d_base.y); //画出虚拟参考线 //声明极轴追踪模式 int iOldPolarMode = 0; //得到原极轴追踪模式 mysys->GetSysVar(_T("AUTOSNAP"), iOldPolarMode); //设置极轴追踪模式，0为不极轴追踪，8为极轴追踪 mysys->SetSysVar(_T("AUTOSNAP"), 8) ; CRailSlopeEditJig *pJig = new CRailSlopeEditJig(); pJig->DoIt(pt_3d_base); //恢复原极轴追踪模式 mysys->SetSysVar(_T("AUTOSNAP"), iOldPolarMode) ; int len = pJig->m_3dPoints.length(); //打开窗体 if (len>=2) { CAcModuleResourceOverride myResources ; RailSlopeEditDlg dlg = new RailSlopeEditDlg(); //值的初始化 dlg.cthRailSlope = pthEnt; dlg.m_left_kmpost = m_left_kmpost; dlg.m_pt3dBasePoint = pthEnt->position(); dlg.m_pt3dStartPoint = pJig->m_pt3dStart; dlg.m_pt3dEndPoint = pJig->m_pt3dEnd; int nRet = dlg.DoModal(); if (nRet == IDOK) { acutPrintf(_T("\n坡度编辑完成")) ; } else if (nRet == IDCANCEL) { acutPrintf(_T("\n坡度编辑已取消")) ; } } //获取名称 pthEnt->downgradeOpen(); } else { AfxMessageBox(_T("选择的不是坡度实体！")) ; bReturn = false ; } if(pEnt!=NULL) { pEnt->unhighlight() ; pEnt->close(); } acedUpdateDisplay(); } //AcDbObjectId dimensionId = CDwgDatabaseUtil::PostToModelSpace(cthRailSlope, m_pDb); } else if (iReturn == RTERROR) { bReturn = false ; } else if (iReturn == RTCAN) { bReturn = true ; }}
//保存当前图层，设置要绘制的图层
AcDbObjectId ojbIdLayerOld = m_pDb->clayer() ;m_pDb->setClayer(ojbIdLayerOld) ; //恢复当前图层
} -
参考意见和网页地址：