AutoCAD_建立直線，圓弧，圓

首先看一下效果圖：

  

分爲4部分，先看代碼最少的計算模塊：

**********Calculation.h*******************

#pragma once

class sAcGePoint2d;
class AcGePoint3d;

class CCalculation
{
public:
	CCalculation(void);
	~CCalculation(void);

	//計算兩點連線的中點
	static AcGePoint2d MiddlePoint(AcGePoint2d pt1, AcGePoint2d pt2);
	static AcGePoint3d MiddlePoint(AcGePoint3d pt1, AcGePoint3d pt2);

	static AcGePoint3d Pt2dTo3d(AcGePoint2d pt);

	//計算常量π的值
	static double PI();
};

 

**********Calculation.cpp*******************

#include "StdAfx.h"
#include "Calculation.h"
#include <math.h>

CCalculation::CCalculation(void)
{
}

CCalculation::~CCalculation(void)
{
}


AcGePoint2d CCalculation::MiddlePoint(AcGePoint2d pt1, AcGePoint2d pt2)
{
	AcGePoint2d pt;
	pt[X] = (pt1[X] + pt2[X]) / 2;
	pt[Y] = (pt1[Y] + pt2[Y]) / 2;

	return pt;
}

AcGePoint3d CCalculation::MiddlePoint(AcGePoint3d pt1, AcGePoint3d pt2)
{
	AcGePoint3d pt;

	pt[X] = (pt1[X] + pt2[X]) / 2;
	pt[Y] = (pt1[Y] + pt2[Y]) / 2;
	pt[Z] = (pt1[Z] + pt2[Z]) / 2;

	return pt;
}

AcGePoint3d CCalculation::Pt2dTo3d(AcGePoint2d pt)
{
	AcGePoint3d ptTemp(pt.x, pt.y, 0);
	return ptTemp;
}

double CCalculation::PI()
{
	return 4 * atan(1.0);//反正切
}

而後咱們看一下，修改顏色，圖層，線條：

**********CModifyEnt.h*******************

#pragma once
#include "StdAfx.h"


class CModifyEnt
{
public:
	CModifyEnt(void);
	~CModifyEnt(void);

	//改變顏色
	static Acad::ErrorStatus ChangeColor(AcDbObjectId entId, Adesk::UInt16 colorIndex);

	//改變圖層
	static Acad::ErrorStatus ChangeLayer(AcDbObjectId entId,CString strLayerName);

	//改變線型
	static Acad::ErrorStatus ChangeLinetype(AcDbObjectId entId,CString strLinetype);
};

 

**********CModifyEnt.cpp*******************

#include "StdAfx.h"
#include "ModifyEnt.h"

CModifyEnt::CModifyEnt(void)
{
}

CModifyEnt::~CModifyEnt(void)
{
}

Acad::ErrorStatus CModifyEnt::ChangeColor(AcDbObjectId entId, Adesk::UInt16 colorIndex)
{
	AcDbEntity *pEntity = NULL;
	// 打開圖形數據庫中的對象
	acdbOpenObject(pEntity, entId, AcDb::kForWrite);

	// 修改實體的顏
	pEntity->setColorIndex(colorIndex);// colorIndex:0～256 的值，其中 0 表明隨塊，256 表明隨層

	// 用完以後，及時關閉
	pEntity->close();

	return Acad::eOk;
}

Acad::ErrorStatus CModifyEnt::ChangeLayer(AcDbObjectId entId, CString strLayerName)
{
	AcDbEntity *pEntity = NULL;
	// 打開圖形數據庫中的對象
	acdbOpenObject(pEntity, entId, AcDb::kForWrite);

	// 修改實體的圖層
	pEntity->setLayer(strLayerName);

	// 用完以後，及時關閉
	pEntity->close();
	return Acad::eOk;
}

Acad::ErrorStatus CModifyEnt::ChangeLinetype(AcDbObjectId entId, CString strLinetype)
{
	AcDbEntity *pEntity = NULL;
	// 打開圖形數據庫中的對象
	acdbOpenObject(pEntity, entId, AcDb::kForWrite);

	// 修改實體的線型
	pEntity->setLayer(strLinetype);

	// 用完以後，及時關閉
	pEntity->close();

	return Acad::eOk;
}

接下來，咱們看最重要的一部分，建立直線，建立圓（4種方法），建立圓弧（5種方法）：

**********CreateEnt.h*******************

#pragma once
#include "StdAfx.h"


class CCreateEnt
{
public:
	CCreateEnt(void);
	~CCreateEnt(void);

	// 將實體添加到圖形數據庫的模型空間
	static AcDbObjectId PostToModelSpace(AcDbEntity* pEnt);

	// 建立一條線
	static AcDbObjectId CreateLine(AcGePoint3d ptStart,AcGePoint3d ptEnd); 
	
	//建立一個圓(圓心、半徑法)（三維）
	// ptCenter：圓心； 
	//radius：半徑；
	//vec：圓所在平面
	static AcDbObjectId CreateCircle(AcGePoint3d ptCenter, AcGeVector3d vec, double radius);
	//建立位於 XOY 平面上的圓（二維）依賴三維法
	static AcDbObjectId CreateCircle(AcGePoint3d ptCenter, double radius);
	//建立一個圓（倆點法）依賴二維法
	static AcDbObjectId CreateCircle(AcGePoint2d pt1, AcGePoint2d pt2);
	//建立一個圓（三點法）依賴二維法
	static AcDbObjectId CreateCircle(AcGePoint2d pt1, AcGePoint2d pt2,AcGePoint2d pt3);

	//建立圓弧（圓心、半徑、圓弧所在的平面、起點角度和終點角度）
	//ptCenter：圓心； 
	//vec：圓弧所在平面
	//radius：半徑；
	//startAngle:起點角度
	//endAngle：終點角度
	static AcDbObjectId CreateArc(AcGePoint3d ptCenter, AcGeVector3d vec, double radius, double startAngle, double endAngle);
	//建立圓弧（二維）依賴於圓弧1法
	static AcDbObjectId CreateArc(AcGePoint2d ptCenter, double radius, double startAngle, double endAngle);
	//建立圓弧（三點法）依賴於二維法
	static AcDbObjectId CreateArc(AcGePoint2d ptStart, AcGePoint2d ptOnArc, AcGePoint2d ptEnd);
	//建立圓弧（起點、圓心、終點）依賴於二維法
	static AcDbObjectId CreateArcSCE(AcGePoint2d ptStart, AcGePoint2d ptCenter, AcGePoint2d ptEnd);
	//建立圓弧(起點、圓心、圓弧角度)依賴於二維法
	static AcDbObjectId CreateArc(AcGePoint2d ptStart, AcGePoint2d ptCenter, double angle);


};

 

**********Calculation.cpp*******************

#include "StdAfx.h"
#include "CreateEnt.h"
#include "Calculation.h"
#include <math.h>
#include "gearc3d.h"

CCreateEnt::CCreateEnt(void)
{
}

CCreateEnt::~CCreateEnt(void)
{
}

AcDbObjectId CCreateEnt::CreateLine(AcGePoint3d ptStart,AcGePoint3d ptEnd)
{
	// 在內存上建立一個新的AcDbLine對象
	//AcGePoint3d ptStart(0, 0, 0);
	//AcGePoint3d ptEnd(100, 100, 0);
	AcDbLine *pLine = new AcDbLine(ptStart, ptEnd);

	
	AcDbObjectId lineId;
	lineId = CCreateEnt::PostToModelSpace(pLine);

	return lineId;
}

AcDbObjectId CCreateEnt::PostToModelSpace(AcDbEntity* pEnt)
{
	// 得到指向塊表的指針
	AcDbBlockTable *pBlockTable = NULL;
	//workingDatabase()可以得到一個指向當前活動的圖形數據庫的指針，
	acdbHostApplicationServices()->workingDatabase()->getBlockTable(pBlockTable, AcDb::kForRead);

	// 得到指向特定的塊表記錄（模型空間）的指針
	AcDbBlockTableRecord *pBlockTableRecord NULL;
	pBlockTable->getAt(ACDB_MODEL_SPACE, pBlockTableRecord,AcDb::kForWrite);

	// 將AcDbLine類的對象添加到塊表記錄中
	AcDbObjectId entId;
	pBlockTableRecord->appendAcDbEntity(entId, pEnt); 

	// 關閉圖形數據庫的各類對象
	pBlockTable->close();
	pBlockTableRecord->close();
	pEnt->close(); 

	return entId;
}

AcDbObjectId CCreateEnt::CreateCircle(AcGePoint3d ptCenter, AcGeVector3d vec, double radius)
{
	AcDbCircle *pCircle = new AcDbCircle(ptCenter, vec, radius);

	// 將實體添加到圖形數據庫
	AcDbObjectId circleId;
	circleId = CCreateEnt::PostToModelSpace(pCircle);

	return circleId;
}

AcDbObjectId CCreateEnt::CreateCircle(AcGePoint3d ptCenter, double radius)
{
	AcGeVector3d vec(0, 0, 1);
	return CCreateEnt::CreateCircle(ptCenter, vec, radius);
}

AcDbObjectId CCreateEnt::CreateCircle(AcGePoint2d pt1, AcGePoint2d pt2)
{ 
	// 計算圓心和半徑
	AcGePoint2d pt = CCalculation::MiddlePoint(pt1, pt2);
	AcGePoint3d ptCenter(pt[X], pt[Y], 0); // 圓心
	double radius = pt1.distanceTo(pt2) / 2;//distanceTo 函數用於計算兩點之間的距離，也就是半徑
	
	// 建立圓
	return CCreateEnt::CreateCircle(ptCenter, radius);
}

AcDbObjectId CCreateEnt::CreateCircle(AcGePoint2d pt1, AcGePoint2d pt2,AcGePoint2d pt3)
{
	/*
	// 使用數學方法
	double xysm, xyse, xy;
	AcGePoint3d ptCenter;
	double radius; 
	xy = pow(pt1[X], 2) + pow(pt1[Y], 2);
	xyse = xy - pow(pt3[X], 2) - pow(pt3[Y], 2);
	xysm = xy - pow(pt2[X], 2) - pow(pt2[Y], 2);
	xy = (pt1[X] - pt2[X]) * (pt1[Y] - pt3[Y]) - (pt1[X] - pt3[X]) * (pt1[Y] - pt2[Y]);
	// 判斷參數有效性
	if (fabs(xy) < 0.000001)
	{
		AfxMessageBox(_T("所輸入的參數沒法建立圓形！"));
		return 0;
	}

	// 得到圓心和半徑
	ptCenter[X] = (xysm * (pt1[Y] - pt3[Y]) - xyse * (pt1[Y] - pt2[Y])) / (2 * xy);
	ptCenter[Y] = (xyse * (pt1[X] - pt2[X]) - xysm * (pt1[X] - pt3[X])) / (2 * xy);
	ptCenter[Z] = 0;
	radius = sqrt((pt1[X] - ptCenter[X]) * (pt1[X] - ptCenter[X]) + (pt1[Y] - ptCenter[Y]) * (pt1[Y] - ptCenter[Y]));
	if (radius < 0.000001)
	{
		AfxMessageBox(_T("半徑太小！"));
		return 0;
	}

	return CCreateEnt::CreateCircle(ptCenter, radius);
*/
	// 使用幾何類
	AcGeCircArc2d geArc(pt1, pt2, pt3);
	AcGePoint3d ptCenter(geArc.center().x, geArc.center().y, 0);

	return CCreateEnt::CreateCircle(ptCenter, geArc.radius());
	
}

AcDbObjectId CCreateEnt::CreateArc(AcGePoint3d ptCenter, AcGeVector3d vec, double radius, double startAngle, double endAngle)
{
	AcDbObjectId arcId;

	AcDbArc *pArc = new AcDbArc(ptCenter, vec, radius, startAngle, endAngle);
	arcId = CCreateEnt::PostToModelSpace(pArc);

	return arcId;
}

AcDbObjectId CCreateEnt::CreateArc(AcGePoint2d ptCenter, double radius, double startAngle, double endAngle)
{
	AcGeVector3d vec(0, 0, 1);
	return CCreateEnt::CreateArc(CCalculation::Pt2dTo3d(ptCenter),vec, radius, startAngle, endAngle);
}

AcDbObjectId CCreateEnt::CreateArc(AcGePoint2d ptStart, AcGePoint2d ptOnArc, AcGePoint2d ptEnd)
{
	// 使用幾何類得到圓心、半徑
	AcGeCircArc2d geArc(ptStart, ptOnArc, ptEnd);
	AcGePoint2d ptCenter = geArc.center();
	double radius = geArc.radius();

	// 計算起始和終止角度
	AcGeVector2d vecStart(ptStart.x - ptCenter.x, ptStart.y - ptCenter.y);
	AcGeVector2d vecEnd(ptEnd.x - ptCenter.x, ptEnd.y - ptCenter.y);
	double startAngle = vecStart.angle();
	double endAngle = vecEnd.angle();

	return CCreateEnt::CreateArc(ptCenter, radius, startAngle, endAngle);
}

AcDbObjectId CCreateEnt::CreateArcSCE(AcGePoint2d ptStart, AcGePoint2d ptCenter, AcGePoint2d ptEnd)
{
	// 計算半徑
	double radius = ptCenter.distanceTo(ptStart);

	// 計算起、終點角度
	AcGeVector2d vecStart(ptStart.x - ptCenter.x, ptStart.y - ptCenter.y);
	AcGeVector2d vecEnd(ptEnd.x - ptCenter.x, ptEnd.y - ptCenter.y);
	double startAngle = vecStart.angle();
	double endAngle = vecEnd.angle();

	// 建立圓弧
	return CCreateEnt::CreateArc(ptCenter, radius, startAngle, endAngle);
}

AcDbObjectId CCreateEnt::CreateArc(AcGePoint2d ptStart, AcGePoint2d ptCenter, double angle)
{
	// 計算半徑
	double radius = ptCenter.distanceTo(ptStart);
	// 計算起、終點角度
	AcGeVector2d vecStart(ptStart.x - ptCenter.x, ptStart.y - ptCenter.y);
	double startAngle = vecStart.angle();
	double endAngle = startAngle + angle;
	// 建立圓弧
	return CCreateEnt::CreateArc(ptCenter, radius, startAngle, endAngle);
}

 

最後，建立AutoCAD命令，達到在AutoCAD命令行中輸入命令，佈局窗口看到咱們的大斧頭的目的：

**********acrxEntryPoint.cpp*******************


static void HHLCreateEntsLine(void)
	{
		AcGePoint3d ptStart(0, 100, 0);
		AcGePoint3d ptEnd(0, -100, 0);
		AcDbObjectId lineId;
		lineId = CCreateEnt::CreateLine(ptStart, ptEnd);
		CModifyEnt::ChangeColor(lineId, 1);

		ptStart.set(-10, 100, 0);
		ptEnd.set(-10, -100, 0);
		lineId = CCreateEnt::CreateLine(ptStart, ptEnd);

		CModifyEnt::ChangeColor(lineId, 1);
		CModifyEnt::ChangeLayer(lineId, _T("虛線"));
		CModifyEnt::ChangeLinetype(lineId, _T("中心線"));
	}

	static void HHLCreateEntsCircle(void)
	{
		// 「圓心、半徑」法建立一個圓
		AcGePoint3d ptCenter(50, 50, 0);
		CCreateEnt::CreateCircle(ptCenter, 5);

		// 兩點法建立一個圓
		AcGePoint2d pt1(70, 100);
		AcGePoint2d pt2(130, 100);
		//CCreateEnt::CreateCircle(pt1, pt2);

		// 三點法建立一個圓
		pt1.set(60, 100);
		pt2.set(140, 100);
		AcGePoint2d pt3(100, 60);
		//CCreateEnt::CreateCircle(pt1, pt2, pt3);
	}

	static void HHLCreateEntsArc(void)
	{
		// 建立位於XOY平面上的圓弧
		AcGePoint2d ptCenter(50, -50);
		CCreateEnt::CreateArc(ptCenter, 100 * sqrt( (double)2 ) / 2, 1 * CCalculation::PI() / 4, 3 * CCalculation::PI() / 4);
		
		// 三點法建立圓弧
		AcGePoint2d ptStart(100, 0);
		AcGePoint2d ptOnArc(120, 50);
		AcGePoint2d ptEnd(100, 100);
		CCreateEnt::CreateArc(ptStart, ptOnArc, ptEnd);
		
		// 「起點、圓心、終點」建立圓弧
		ptStart.set(100, 100);
		ptCenter.set(50, 150);
		ptEnd.set(0, 100);
		CCreateEnt::CreateArcSCE(ptEnd , ptCenter, ptStart);
		
		// 「起點、圓心、圓弧角度」建立圓弧
		ptStart.set(0, 0);
		ptCenter.set(-50, 50);
		CCreateEnt::CreateArc(ptStart, ptCenter, CCalculation::PI() / 2);
	}


ACED_ARXCOMMAND_ENTRY_AUTO(CCreateEntsApp, HHL, CreateEntsLine, CreateLine, ACRX_CMD_TRANSPARENT, NULL)
ACED_ARXCOMMAND_ENTRY_AUTO(CCreateEntsApp, HHL, CreateEntsCircle, CreateCircle, ACRX_CMD_TRANSPARENT, NULL)
ACED_ARXCOMMAND_ENTRY_AUTO(CCreateEntsApp, HHL, CreateEntsArc, CreateArc, ACRX_CMD_TRANSPARENT, NULL)

注意：最後這部分代碼是加在現有cpp裏的，該cpp爲程序的主入口