AutoCAD DevBlog

Using AcEditor::commandEnded to change the layer of a block reference when it is inserted

By Philippe Leefsma

Q:

When a BlockReference is created with the INSERT command, I would like to change the layer it is on. Is there a way to do this?

A:

One approach to consider is to use AcEditor::commandEnded: If the command was INSERT, then a selection set is used to get the last entity added to the drawing. A transaction is used to open the entity and change the layer. The attached example does this.

Here is the pertinent code:

 

void ASDKwbEdReactor::commandEnded(

const ACHAR * cmdStr)

{

     if(_tcscmp(cmdStr,_T("INSERT")) == 0)

     {

          if (!acdbHostApplicationServices()

              ->workingDatabase())

                return;

 

           // Get entities just operated on

           ads_name sset;

           int err = acedSSGet(_T("L"),

           NULL, NULL, NULL, sset);

 

           if (err != RTNORM)

           {

              acutPrintf(

                _T("\nError acquiring last entity"));

                return;

           }

 

           actrTransactionManager->startTransaction();

 

           long length;

           acedSSLength(sset, &length);

 

           ads_name en;

           AcDbObjectId eId;

           AcDbEntity *pEnt;

 

           for (long i=0; i < length; i++)

           {

                acedSSName(sset, i, en);

 

                Acad::ErrorStatus es =

                    acdbGetObjectId(eId, en);

 

                if (es != Acad::eOk)

                {

                  acutPrintf(

                   _T("\nacdbGetObjectId failed: ")

                   _T("Entity <%lx,%lx>, error %s."),

               en[0], en[1],

                   acadErrorStatusText(es));

 

                     acedSSFree(sset);

                     return;

                }

 

               es = actrTransactionManager->getObject(

                    

               (AcDbObject*&)pEnt,

                    eId, AcDb::kForWrite);

 

                if (es == Acad::eOk)

                {

                  // This maybe a redundant test as

                  // INSERT was the command

                     if ( pEnt->isA() ==

                         AcDbBlockReference::desc() )

                     {

                           // You need to have an

                           // existing TEST layer

                           pEnt->setLayer(_T("TEST"));

                     }

                }

                else

                {

                     acutPrintf(

                       _T("\ngetObject failed: %s."),

                       acadErrorStatusText(es));

 

                     actrTransactionManager->

                        abortTransaction();

                     acedSSFree(sset);

                     return;

                }

           }

 

           actrTransactionManager->endTransaction();

           acedSSFree(sset);

     }

}

 

EdReactorDemo.zip

How to locate the path used for support files

By Philippe Leefsma

Q:

AutoCAD puts support files (i.e. acad.pgp) in the Users/username/... folder. My program searches for the acad.pgp and other support files to update. How can I easily locate this directory?

A:

There are a couple of means available to retrieve this path. One is to get the value from the Registry. It is stored in the RoamableRootFolder key in this location: 
HKEY_CURRENT_USER\Software\Autodesk\AutoCAD\<Release>\ACAD-<Version>:<Language>

You could use the value of CurVer key in this location
HKEY_CURRENT_USER\Software\Autodesk\AutoCAD\<Release> To first get the CurVer to get the correct location for different AutoCAD based products.

Another approach would be to use the sysvar roamablerootprefix. Which will also return this path.

Accessing the TrueColor property using Visual LISP

By Philippe Leefsma

Q:

How to access the TrueColor property of an entity in AutoCAD? Also, is there a way to set an object's color back to "ByLayer"?

A:

First, it is necessary to access the object's TrueColor property, using vlax-get-property.  The RGB (Red, Green and Blue) values of TrueColor are read-only, so you can not individually modify them.  You must invoke the SetRGB method and set all three values at once.  Then, using vlax-put-property, you can set the object's TrueColor property to reflect the new RGB values.  You will notice that an object whose color is "ByLayer" returns RGB values of R=0, G=0, B=0.  However, setting these values explicitly, with SetRGB, will not restore the color to "ByLayer".  To reset the color to "ByLayer", it is necessary to set TrueColor's ColorIndex property to acBylayer.  The example below creates a line, whose color is initially "ByLayer".  We then change it to blue, and finally back to ByLayer:

(defun c:TestTrueClr()
   (vl-load-com)
   (setq oApp (vlax-get-Acad-Object)
           oDoc (vla-get-ActiveDocument oApp)
           oMSp (vla-get-ModelSpace oDoc)
   )
   ;; Add a Line
   (setq oLine (vla-AddLine oMSp  (vlax-3d-point '(1.0 1.0 0.0))  (vlax-3d-point '(10.0 10.0 0.0))))
    (vla-update oLine)

   ;; Get the current color values
   (setq oColor (vlax-get-property oLine 'TrueColor)
           clrR (vlax-get-property oColor 'Red)
           clrG (vlax-get-property oColor 'Green)
           clrB (vlax-get-property oColor 'Blue)
   )
   (alert (strcat "Old Color - Red: " (itoa clrR) " Green: " (itoa clrG) " Blue: " (itoa clrB)))

   ;; Set TrueColor to blue (R=0, G=101, B=204)
   (vlax-invoke-method oColor 'SetRGB 0 101 204)
   (vlax-put-property oLine 'TrueColor oColor)
   (vla-update oLine)

   ;; Inspect the new color values
   (setq oColor (vlax-get-property oLine 'TrueColor)
           clrR (vlax-get-property oColor 'Red)
           clrG (vlax-get-property oColor 'Green)
           clrB (vlax-get-property oColor 'Blue)
   )
   (alert (strcat "New Color - Red: " (itoa clrR) " Green: " (itoa clrG) " Blue: " (itoa clrB)))
  
   ;; Reset color to acBylayer
   (vlax-put-property oColor 'ColorIndex acByLayer)
   (vlax-put-property oLine 'TrueColor oColor)
   (vla-update oLine)

   ;; Inspect the color values
   (setq oColor (vlax-get-property oLine 'TrueColor)
           clrR (vlax-get-property oColor 'Red)
           clrG (vlax-get-property oColor 'Green)
           clrB (vlax-get-property oColor 'Blue)
   )
   (alert (strcat "New Color - Red: " (itoa clrR) " Green: " (itoa clrG) " Blue: " (itoa clrB)))
)

Is there a way to determine if vertices of wide polyline are beveled?

By Philippe Leefsma

Q:

If a polyline has multiple segments with different widths, the polyline maybe beveled at the point where the segments meet. Is there a way to determine programmatically which vertices of a polyline are beveled?  

A:

There is not a property that will provide this information directly. One suggestion would be to calculate the angles between the polyline segments. The angles that determine if the bevel is drawn can be estimated from this comment in the regen code:

/* Polyline bevelling criteria: allow bevelling if two edges meet at (roughly) 15 to 179.5 degrees. */
#define MINBEVEL .25 /* About sin(15 deg) */

#define MAXBEVEL .009 /* About sin(.5 d) (= sin(179.5 d)) */

Visual LISP example for Controlling Drawing Properties with vla-SetCustomByIndex and similar methods

By Philippe Leefsma

Q:

I need a Visual Lisp example for SetCustomByIndex, SetCustomByKey, GetCustomByIndex and GetCustomByKey.

A:

Here is an example that adds a custom drawing property. It then changes and gets the values:

(defun c:dProps2 (/ dProps dProp)
   (vl-load-com)
   (setq acadObject (vlax-get-acad-object))
   (setq acadDocument (vla-get-ActiveDocument acadObject))
   ;;Get the SummaryInfo
   (setq dProps (vlax-get-Property acadDocument 'SummaryInfo))
   ; comment this vla-addCustomInfo if the entries already exist in
   ; the drawing properties, (which they will after running this one time)
  (vla-AddCustomInfo dProps "wbKey" "wbValue")
  
  (vla-SetCustomByIndex dProps 0 "wbKey" "wbValue2")
  (vla-setCustomByKey dProps "wbKey" "wbValue3")
  (vla-getCustomByKey dProps "wbKey" 'myValue)
  (vla-getCustomByIndex dProps 0 'myValue1 'myValue2)
  (princ (strcat "wbKey value = " myValue "\n"))
  (princ (strcat "Name = " myValue1 "\n"))
  (princ (strcat "Value = " myValue2 "\n"))
  (princ) 
)

MEASURE command in a lisp function is inconsistent

By Philippe Leefsma

Q:

I am using the measure" command in a lisp routine. On some polylines the first mark is incorrect for example if I use 10 for the distance the first mark is not 10 units from the begining of the line. Here is the code I am trying to use:

(Defun c:test (/)
   (setq lineData (entsel "\nSelect a line:")
            lineObj   (car lineData)
   ) ;_ end of setq
   (command "measure" lineObj  10)
) ;_ end of Defun

A:

When you manually use the MEASURE command it starts adding the points nearest to the end of the line where you selected. There does not seem to be a way to consistently control which end of the line the command MEASURE starts measuring from when the entity name is passed to the command in the lisp routine instead of selecting the entity. Another approach to consider would be to use vlax-curve-getPointAtDist. This example places points along the selected polyline at the same location as the Measure command would with a distance of 10.

(Defun c:test (/)
  (vl-load-com)
  (setq acadDoc  (vla-get-ActiveDocument (vlax-get-Acad-Object))
           mSpace   (vla-get-modelspace acadDoc)
           entData   (entsel "\nSelect a polyline:")
           spdata     (car entData)
           plineHandle (cdr (assoc 5 (entget spData)))
           plineObj    (vla-handleToObject acadDoc plineHandle)
           endSpline   (vlax-curve-getEndParam plineObj)
           pLength     (vlax-curve-getDistAtParam plineObj endSpline)
            numOfPoints (fix (/ pLength 10))
  ) ;setq
  (setq count 1)
  (repeat numOfPoints
    (setq dist (* 10 count))
    (setq pnt1 (vlax-curve-getPointAtDist plineObj dist))
    (vla-addpoint mspace (vlax-3d-Point pnt1))
    (setq count (+ count 1))
  ) ;repeat
)

The MEASURE command will also allow you to insert a block along the line. The example below inserts a block named "testBlock" and rotates it so that it is close to the rotation of the angle at that point along the line. This could be changed to get a higher degree of accuracy for the angle. You could get a point that is a little behind and a little ahead to determine the required angle.

NOTE: There is no error checking, and the block named "testBlock" needs to be available in the drawing.

(Defun c:test (/)
  (vl-load-com)
  (setq acadDoc  (vla-get-ActiveDocument (vlax-get-Acad-Object))
           mSpace   (vla-get-modelspace acadDoc)
           entData   (entsel "\nSelect a polyline:")
           spdata     (car entData)
           plineHandle (cdr (assoc 5 (entget spData)))
           plineObj    (vla-handleToObject acadDoc plineHandle)
           endSpline   (vlax-curve-getEndParam plineObj)
           pLength     (vlax-curve-getDistAtParam plineObj endSpline)
           numOfPoints (fix (/ pLength 10))
  ) ;setq
  (setq count 1)
  (repeat numOfPoints
    (setq dist (* 10 count))
    (setq pnt1 (vlax-curve-getPointAtDist plineObj dist))
    (setq dist2 (+ dist 0.1)) 
    ;; get a sample point that is 0.1 ahead of the point that will

    ;;be used for insertion
    (setq pnt2 (vlax-curve-getPointAtDist plineObj dist2))
    ;; get the angle between the insertion point and the sample point
    (setq ang1 (angle pnt1 pnt2))
    (vla-insertblock mspace (vlax-3d-Point pnt1) "testBlock" 1.0 1.0 1.0 ang1)
    (setq count (+ count 1))
  ) ;repeat
)

Using unmanaged dll's for resource-only dll's used by AutoCAD menus

By Philippe Leefsma

Q:

Is there a way to build a resource-only DLL for an AutoCAD menu using Visual Studio? 

A:

A resource-only dll for an AutoCAD menu needs to be created as an unmanaged dll. To create a resource-only dll as an unmanaged dll, use a C++ dll project. In File->New Project, choose win32 project and then choose a "dll".  You can then add your bitmaps into the resource section. The attached zip file has an example.

ResDll.zip

How to transform a block reference and all its attributes using ObjectARX?

By Philippe Leefsma

Q:

How do I position, rotate or scale a block reference and all its attributes?

A:

The functions AcDbBlockReference::setPosition(), AcDbBlockReference::setRotation() and AcDbBlockReference::setScaleFactors() all
work on just the block reference. They do not transform the attributes attached to the block.

The easiest way to transform a block reference and all its attributes is to call AcDbEntity::transformBy() on the block reference. This operation transforms the block and all its attributes in exactly the same way as it does for any other entity. This function can be used to translate, rotate or scale the block reference.

Here is the code for four simple commands:

AcDbBlockReference * getBR();

 

//TRANS - translates the selected block reference by (100,100,0).

void Asdktrans()

{

   AcDbBlockReference * pBR = getBR();

 

   if (pBR == NULL)

     return;

 

   AcGeMatrix3d mat;

   mat = mat.setToTranslation(AcGeVector3d(100,100,0));

   pBR->transformBy(mat);

 

   pBR->close();

}

 

//ROT - rotates the selected block reference by 45 degrees.

void Asdkrot()

{

   AcDbBlockReference * pBR = getBR();

 

   if (pBR == NULL)

     return;

 

   AcGeMatrix3d mat;

   mat = mat.rotation(0.785398, pBR->normal(), pBR->position());

   pBR->transformBy(mat);

 

   pBR->close();

}

 

//SCAL - scales the selected block reference by a factor of 2.

void Asdkscal()

{

   AcDbBlockReference * pBR = getBR();

   if (pBR == NULL)

     return;

 

   AcGeMatrix3d mat;

   mat = mat.scaling(2, AcGePoint3d(0,0,0));

   pBR->transformBy(mat);

 

   pBR->close();

}

 

//ROTSCALTRANS - performs all three operations in a single call to transformBy().

void Asdkrotscaltrans()

{

   AcDbBlockReference * pBR = getBR();

 

   if (pBR == NULL)

     return;

 

   AcGeMatrix3d mat1;

   mat1 = mat1.rotation(0.785398, pBR->normal(), pBR->position());

   AcGeMatrix3d mat2;

   mat2 = mat2.scaling(2, AcGePoint3d(0,0,0));

   AcGeMatrix3d mat3;

   mat3 = mat3.setToTranslation(AcGeVector3d(100,100,0));

 

   AcGeMatrix3d mat;

   mat = mat1*mat2*mat3;

   pBR->transformBy(mat);

 

   pBR->close();

}

 

// Opens block reference chosen by user

AcDbBlockReference * getBR()

{

  ads_name ename;

  ads_point pt;

  AcDbObjectId objId;

  Acad::ErrorStatus es;

 

  if (RTNORM != acedEntSel(_T("\nSelect Block : "), ename, pt))

    return NULL;

 

  es = acdbGetObjectId(objId, ename);

  if (es != Acad::eOk)

    return NULL;

 

  AcDbBlockReference * pBR;

  AcDbObject * pObj;

 

  acdbOpenObject(pObj, objId, AcDb::kForWrite);

 

  pBR = AcDbBlockReference::cast(pObj);

 

  if (pBR == NULL)

  {

    pObj->close();

    acutPrintf(_T("\nThis is not a block."));

    return NULL;

  }

 

  return pBR;

}

Vetoing QUIT in AutoCAD

By Philippe Leefsma

Q:

How can I veto quit in AutoCAD?

A:

There are two situations to consider:

1) Subclass the AutoCAD main frame and watch for WM_CLOSE message. This message is generated when user tries to quit AutoCAD using any of the possible methods. In the sample, we veto the quitting of AutoCAD, but this can be modified to make changes in the documents, save them and then allow AutoCAD to quit. This way you can avoid the save dialog while quitting AutoCAD.

2) Using the event AcApDocManagerReactor::documentLockModeChanged() to trap the EXIT command that the user can issue at command prompt.

The attached arx sample implements both approaches.

ArxVetoQuit.zip

Localizing AutoCAD / AutoCAD OEM in other languages

By Philippe Leefsma

Q:

Can I localize AutoCAD / AutoCAD OEM in other languages?

A:

AutoCAD and AutoCAD OEM are built the same way with regards to localization. Localizable components in AutoCAD are:

- Menu
- MNL
- Lisp
- DCL
- PGP
- Pattern file .PAT
- Linetype file .LIN
- Shape/Font
- Help file (.hlp, .chm)
- Templates
- AutoCAD Core (Windows resource file + linked XMX file)
- Drivers (Windows resource file)
- Externsions (Windows resource file and/or XMX file)
- Others (.htm, .txt, .bmp, ...)

In each of these components there are localizable and non localizable strings. Forgetting to localize one string or localizing one non-localizable string would possibly break the component feature. So it must be done carefully.

All components can be localized by third party if they have an agreement with AutoCAD to do this, excepting few. All the components using a XMX file cannot be localized because the XMX format is a binary encrypted Autodesk file format and Autodesk does not expose any API or tools to work with XMX file.

One solution to this problem is to replace the XMX file by a localized version of the same XMX file from another AutoCAD version if it is made from the same build. It must be from the same build (or similar) to ensure the same number of localized messages contained in the XMX file.

However, this solution will work for all except in one case. The AutoCAD core component XMX file cannot be exchanged by another one, because it is linked to the EXE it was compiled for. For example a German XMX file will not work on a French AutoCAD release. Since you can replace the resource file, but not the XMX file, it means that the AutoCAD core will be partially localized. Most command prompts will remain in the original language unless autodesk provides the proper localized XMX file linked with that particular AutoCAD release.