圆柱体

admin1

// Add an entity to the current database.
Acad::ErrorStatus postToDb(AcDbEntity* pEnt)
{
        Acad::ErrorStatus      es, es2;
        AcDbBlockTable*        pBlockTable = 0;
        AcDbBlockTableRecord*  pSpaceRecord = 0;

        if (!pEnt)
                return Acad::eNullEntityPointer;

        AcDbDatabase *pDb = acdbHostApplicationServices()->workingDatabase();
        if ((es = pDb->getBlockTable(pBlockTable, AcDb::kForRead)) != Acad::eOk)
                return es;

        if ((es = pBlockTable->getAt(ACDB_MODEL_SPACE, pSpaceRecord, AcDb::kForWrite)) == Acad::eOk)
        {
                AcDbObjectId objId;
                es = pSpaceRecord->appendAcDbEntity(objId, pEnt);
                es2 = pSpaceRecord->close();

                if (es == Acad::eOk)
                {
                        es2 = pEnt->downgradeOpen();
                        es2 = pEnt->draw();
                        pEnt->close();
                }
        }
        es2 = pBlockTable->close();

        return es;
}

void CreateCylinder()
{
        double diameter=50.0;
        AcGePoint3d p1(0,0,0), p2(0,0,100);

        AcGeVector3d v12(p2-p1);
        AcGePoint3d ptMid = p1 + v12/2;

        Acad::ErrorStatus es;
        AcDb3dSolid *cylinder = new AcDb3dSolid();
        cylinder->setDatabaseDefaults(); // set current color, layer and linetype

        double height = v12.length(), radius= diameter/2;
        es = cylinder->createFrustum(height, radius, radius, radius);

        // createFrustum() creates a cylinder with midpoint at 0,0,0 and rotation axis=Z
        // So we have to align the cylinder:
        AcGeVector3d vx, vy, vz(v12 / height);
        vx = vz.perpVector();
        vy = vz.crossProduct(vx);

        AcGeMatrix3d mat;
        mat.setCoordSystem(ptMid, vx, vy, vz);
        es = cylinder->transformBy(mat);
        es = postToDb(cylinder);
}