如何获取AUTOCAD图形边界坐标

Getimageclipboundarycoordinates

By

XiaodongLiang

Issue

Icansetimage’sclipbyAcadRasterImage.ClipBoundary,buthowdoIgettheAcadRasterImage'sclipboundarycoordinates?Iknowifitisrectangular,Icangetitsboundingbox,widthandheight.But,iftheclipboundaryisofairregularshape,Ican'tfindanyexposedmethodstogetsuchdata.

Solution

TheObjectARXAcDbRasterImage::clipBoundary()equivalentfunctionalityisnotexposedinthecurrentActiveXAutomationModel.

Wecanworkaroundthislimitationbyexposinganinterfacethatdoesexactlythat.Thewholeprojectisattached:

DownloadImgClipBoundary

STDMETHODIMPCClipBoundaryObj::GetImageClipBoundary(

VARIANT*pVarDblArray,

VARIANTacadImage)

{

//TODO:Addyourimplementationcodehere

try

{

CComQIPtr<IAcadRasterImage>

pAcadImage(acadImage.punkVal);

if(!pAcadImage)

throw

E_POINTER;

CComQIPtr<IAcadBaseObject>

pBaseObj(pAcadImage);

if(!pBaseObj)

throw

E_POINTER;

AcDbObjectIdid;

pBaseObj->GetObjectId(&id);

AcDbObjectPointer<AcDbRasterImage>

pImage(id,AcDb::kForRead);

if(pImage.openStatus()!=Acad::eOk)

throw

E_UNEXPECTED;

AcGePoint2dArray

array

=

pImage->clipBoundary();

intlen=

array.length();

if(len==0)

throw

E_FAIL;

AcGeMatrix3dmat;

pImage->getPixelToModelTransform(mat);

mat.inverse();

AcAxPoint2dArraypts;

for(int

i=0;i<len;i++)

{

AcGePoint3dpt(array[i].x,

array[i].y,0);

pt.transformBy(mat);

pts.append(AcGePoint2d(pt.x,pt.y));

}

pts.setVariant(pVarDblArray);

}

catch(const

HRESULTh)

{

//fornow

acutPrintf(_T("\nSomethingiswrong."));

return

h;

}

return

S_OK;

}

Tousetheabilityabove,

1.buildtheattachedproject,loaditinAutoCAD

2.

openVBAIDE

3.Tools>>Reference:selectARX.nowyoucanseeonelibraryisavailableinthelist.

4.RuntheVBAcodebelow.Itcreatesanimageandsetitsclip,andgetsitsclipboundarybythemethodprovidedinasdkImgClipBoundary.

SubExample_ClipBoundary()

'Thisexampleaddsarasterimageinmodelspace.

'Itthenclipstheimagebasedonaclipboundary.

'Thisexampleusesthe"downtown.jpg"foundinthesample

'directory.Ifyoudonothavetheimage,oritislocated

'inadifferentdirectory,insertavalidpathandnameforthe

'imageNamevariablebelow.

DiminsertionPoint(0To2)AsDouble

DimscalefactorAsDouble

DimrotationAngleAsDouble

DimimageNameAsString

DimrasterObjAsAcadRasterImageimageName="C:\01_SDK\ObjectARX2023\samples\graphics\AsdkTransientGraphicsSampFolder\Airport-Image.jpg"

insertionPoint(0)=5#:insertionPoint(1)=5#:insertionPoint(2)=0#

scalefactor=2#

rotationAngle=0

OnErrorResumeNext

'Createsarasterimageinmodelspace

SetrasterObj=(imageName,insertionPoint,scalefactor,rotationAngle)

IfErr.Description="Filererror"Then

MsgBoximageName&"couldnotbefound."

ExitSub

EndIf

ZoomAllMsgBox"Cliptheimage?",,"ClipBoundaryExample"

'Establishtheclipboundarywithanarrayofpoints

DimclipPoints(0To9)AsDouble

clipPoints(0)=6:clipPoints(1)=6.75

clipPoints(2)=7:clipPoints(3)=6

clipPoints(4)=6:clipPoints(5)=5

clipPoints(6)=5:clipPoints(7)=6

clipPoints(8)=6:clipPoints(9)=6.75

'Cliptheimage

rasterObj.ClipBoundaryclipPoints

'Enablethedisplayoftheclip

rasterObj.ClippingEnabled=True

ThisDrawing.RegenacActiveViewport

'MsgBox"Theimagehasbeenclipped.",,"ClipBoundaryExample"

OnErrorGoTo0

DimxObjAsasdkImgClipBoundaryLib.ClipBoundaryObj

SetxObj=ThisDrawing.Application.GetInterfaceObject("ImgClipBoundary.ClipBoundaryObj.1")

Dimbound