测试结果：这个是按0.1,0.1,0.1,0.3,0.4的比例划分的。
插件描述：这个插件主要是选择一个多段线poly，设置poly的close属性为true，在poly任意一侧画一条长线line（line画的时候不能与poly相交），找到line的垂直向量p'yXl，这个pyXl是要往与poly能相交的方向。在找到这个line与poly相切的时候。然后取每次平移的步进值bujin，因为这个poly的总面积有大有小，所以我是取总面积totaArea/2000在开方，如果这个bujin<=1,则直接取1，这样对于面积很大的poly也不需要平移很多次。然后就是利用acedTraceBoundary函数来获取平移后的
切线与poly形成的封闭多段线pl，求这个pl的面积是否大与按比例分割后的面积。
需要注意的地方：在使用acedTraceBoundary的时候，必须确认poly和平移的切线都是close掉的，不然无法求出pl。如果没有acedTraceBoundary函数，可以这样：
//ads_point pt = { seedPoint.x,seedPoint.y,seedPoint.z };
//acedCommandS(RTSTR, L"-boundary", RTPOINT, pt, RTSTR, L"", RTNONE);
//acdbEntLast(pent);
////acedRedraw(pent, 3);
//AcDbObjectId eId;
//acdbGetObjectId(eId, pent);
//AcDbPolyline * pEnt = NULL;
//ErrorStatus es = acdbOpenObject(pEnt, eId, AcDb::OpenMode::kForWrite);来获得封闭的多段线，然后在求面积。
下面给出详细代码:
求pyXl：
AcGeVector3d CAreaFenGe::GetDirection()
{
//l2pt和l1pt是在poly侧边画的线的端点
AcGeVector3d lineDirc = l2Pt - l1Pt;
AcGeVector3d lineDirc2 = l2Pt - l1Pt;
AcGePoint3d centerPt((l2Pt.x + l1Pt.x) / 2, (l2Pt.y + l1Pt.y) / 2, 0);
AcGePoint3d ptCloset;
poly->getClosestPointTo(centerPt, ptCloset, false);
AcDbLine *line1 = AcDbLine::cast(line->clone());
AcDbLine *line2 = AcDbLine::cast(line->clone());
double len = ptCloset.distanceTo(centerPt);
AcGeVector3d pyXl1 = lineDirc.rotateBy(-1 * CMathUtil::PI() / 2, AcGeVector3d::kZAxis);
AcGeVector3d pyXl2 = lineDirc2.rotateBy(CMathUtil::PI() / 2, AcGeVector3d::kZAxis);
line1->transformBy(AcGeMatrix3d::translation(pyXl1.normal()*len*1.5));
line2->transformBy(AcGeMatrix3d::translation(pyXl2.normal()*len*1.5));
AcGePoint3dArray p3dArr1, p3dArr2;
poly->intersectWith(line1, AcDb::Intersect::kExtendArg, p3dArr1, 0, 0);
poly->intersectWith(line2, AcDb::Intersect::kExtendArg, p3dArr2, 0, 0);
if (p3dArr1.length() > 0) {
pyXl = pyXl1;
}
else if(p3dArr2.length()>0){
pyXl = pyXl2;
}
else {
pyXl = AcGeVector3d(3, -1, 0);//这个可以注释掉
}
delete line1;
line1 = NULL;
delete line2;
line2 = NULL;
return pyXl;
}获得切线:
//得到切线
AcGePoint3d CAreaFenGe::GetQieDian(AcDbLine * &line1)
{
line1 = new AcDbLine(l1Pt, l2Pt);
AcGePoint3dArray ptArr;
while (ptArr.length() < 1) {
poly->intersectWith(line1, AcDb::Intersect::kOnBothOperands, ptArr, 0, 0);
line1->transformBy(AcGeMatrix3d::translation(pyXl.normal() * 1));
}
poly->close();
if (ptArr.length() > 0)
return ptArr[0];
else
return AcGePoint3d::kOrigin;
}得到面积:
bool CAreaFenGe::GetPyPolyline(AcGePoint3d seedPoint, double & a)
{
AcDbVoidPtrArray ptrArr;
ErrorStatus es = acedTraceBoundary(seedPoint, false, ptrArr);
if (es != Acad::eOk) {
acutPrintf(L"\nboundary=%d", es);
return false;
}
AcDbPolyline * pl = NULL;
pl = (AcDbPolyline*)ptrArr[0];
pl->setColorIndex(1);
pl->getArea(a);
pl->erase();
pl->close();
pl = NULL;
return true;
}主要步骤：
void CAreaFenGe::Command()
{
ErrorStatus es;
AcDbLine * lQieXian = NULL;
AcGePoint3d ptQieDian = GetQieDian(lQieXian);
acutPrintf(L"\nptQieDian=[%.2f,%.2f,%.2f]", ptQieDian.x, ptQieDian.y, ptQieDian.z);
ptQieDian=ptQieDian.transformBy(AcGeMatrix3d::translation(pyXl.normal() * 5));
acutPrintf(L"\nptQieDian2=[%.2f,%.2f,%.2f]", ptQieDian.x, ptQieDian.y, ptQieDian.z);
if (ptQieDian.x == 0 && ptQieDian.y == 0) {
return;
}
double bujin = sqrt(totalArea * 1 / 2000);
if (bujin <= 1) {
bujin = 1;
}
AcDbObjectId qxId;
lQieXian->transformBy(AcGeMatrix3d::translation(pyXl.normal() * bujin*3));
es = acdbOpenObject(poly, plId, AcDb::kForRead);
AcGePoint3dArray ptJdArr;
poly->intersectWith(lQieXian, AcDb::Intersect::kOnBothOperands, ptJdArr, 0, 0);
if (ptJdArr.length() >= 2) {
ptQieDian=AcGePoint3d((ptJdArr[0].x+ ptJdArr[1].x)/2, (ptJdArr[0].y + ptJdArr[1].y) / 2,0);
ptQieDian= ptQieDian.transformBy(AcGeMatrix3d::translation(pyXl.normal() * -bujin*1.5));
}
poly->close();
qxId = CDwgDataBaseUtil::PostToModelSpace(lQieXian);
lQieXian->close();
lQieXian = NULL;
//AcDbPolyline * ptPy = new AcDbPolyline();
//ptPy->setColorIndex(5);
//AcDbObjectId ptId;
AcGePoint3dArray ptJdArr2;
for (int i = 0; i < (int)vecArea.size(); i++)
{
AcGePoint3d ptCopyQd = ptQieDian;
double a = 0.0;
while (a < vecArea[i]) {
bool flag = GetPyPolyline(ptQieDian, a);
if (!flag) {
return;
}
es = acdbOpenObject(lQieXian, qxId, AcDb::kForWrite);
lQieXian->transformBy(AcGeMatrix3d::translation(pyXl.normal() * bujin));
ptJdArr2.removeAll();
es = acdbOpenObject(poly, plId, AcDb::kForRead);
poly->intersectWith(lQieXian, AcDb::Intersect::kExtendArg, ptJdArr2, 0, 0);
poly->close();
if (ptJdArr2.length() < 1) {
lQieXian->close();
break;
}
lQieXian->close();
}
acdbOpenObject(lQieXian, qxId, AcDb::kForWrite);
es = acdbOpenObject(poly, plId, AcDb::kForRead);
ptJdArr.removeAll();
poly->intersectWith(lQieXian, AcDb::Intersect::kExtendArg, ptJdArr, 0, 0);
AcGePoint3d preCenter;
if (ptJdArr.length() >= 2) {
AcDbLine* lFg = new AcDbLine(ptJdArr[0], ptJdArr[1]);
preCenter = AcGePoint3d((ptJdArr[0].x + ptJdArr[1].x) / 2, (ptJdArr[0].y + ptJdArr[1].y) / 2, 0);
lFg->setColorIndex(2);
CDwgDataBaseUtil::PostToModelSpace(lFg);
lFg->close();
}
else {
poly->close();
lQieXian->erase();
lQieXian->close();
lQieXian = NULL;
//ptId = CDwgDataBaseUtil::PostToModelSpace(ptPy);
return;
}
poly->close();
AcDbPolyline *pCopyQx = (AcDbPolyline*)lQieXian->clone();
pCopyQx->transformBy(AcGeMatrix3d::translation(pyXl.normal() *bujin));
if (i != (int)vecArea.size() - 1) {
es = acdbOpenObject(poly, plId, AcDb::kForRead);
ptJdArr.removeAll();
poly->intersectWith(pCopyQx, AcDb::Intersect::kExtendArg, ptJdArr, 0, 0);
if (ptJdArr.length() >= 2) {
ptQieDian = AcGePoint3d((ptJdArr[0].x + ptJdArr[1].x) / 2, (ptJdArr[0].y + ptJdArr[1].y) / 2, 0);
ptQieDian = AcGePoint3d((preCenter.x + ptQieDian.x) / 2, (preCenter.y + ptQieDian.y) / 2, 0);
}
qxId = CDwgDataBaseUtil::PostToModelSpace(pCopyQx);
pCopyQx->close();
poly->close();
pCopyQx = NULL;
}
lQieXian->erase();
lQieXian->close();
lQieXian = NULL;
//当运行到最后一个面积时，就不复制了
if (i == (int)vecArea.size() - 1) {
delete pCopyQx;
pCopyQx = NULL;
break;
}
}
/*if (ptId.isNull()) {
ptId = CDwgDataBaseUtil::PostToModelSpace(ptPy);
ptPy->close();
}*/
}构造函数：
CAreaFenGe::CAreaFenGe(ACHAR *fenGeStr, AcDbPolyline *&p, AcDbLine *&l)
{
vector<CString> vec;
CStringUtil::Split(W2T(fenGeStr), L",", vec, false);
for (int i = 0; i < (int)vec.size(); i++)
{
vecFenGe.push_back(_wtof(vec.at(i)));
}
this->poly = p;
this->line = l;
l1Pt = l->startPoint();
l2Pt = l->endPoint();
if (poly->isClosed() == false) {
poly->setClosed(true);
}
poly->getArea(totalArea);
for (int i = 0; i < (int)vecFenGe.size(); i++)
{
vecArea.push_back(totalArea*vecFenGe.at(i));
acutPrintf(L"%.2f", vecArea[i]);
}
GetDirection();
plId = poly->objectId();
}
