Implementing ATL COM object wrapper  for Raster Manager API

 

Part of product

Research

Date

February 2002

Programming languages  

VC++ & ATL

Company

Description

In first releases of MicroStation v8, DGN COM object didn't offer Raster Management functionalities. That led me to think on alternatives - how to create COM object encapsulating MDL API for Raster Management. I have used ATL in Visual Studio v 6 and implemented functions for open and close raster as well for raster notification  events. The COM object was subsequently tested in different environments (JScript, VBScript, VBA, WSH, HTML). Now raster Object is implemented in MicroStation COM object, but still this work showed how to make custom ATL objects from MDL API.

 

ATL COM object  - test code snippet for Raster Manager

 

#include "stdafx.h"

#include "RasterObjx.h"

#include "RasterMan.h"

static void *rasObj;

....

//------------------ open raster test

STDMETHODIMP CRasterMan::OpenRaster(BSTR fileNameP, int view){

 char name[256];long ramHnd;

 

 WideCharToMultiByte(CP_ACP, 0, fileNameP,SysStringLen(fileNameP)+1, name, 256, 0, 0);

 mdlRaster_fileOpen(&ramHnd,name,mdlModelRef_getActive(),

 FILE_ACCESSMODE_READ,EVENT_UPDATE);

 RasterRenderingInfo rendInfo;

 mdlRaster_renderingInfoGet(&rendInfo,ramHnd);

 rendInfo.view1 = 1; // display in view 1

 mdlRaster_renderingInfoSet(&rendInfo,ramHnd,EVENT_UPDATE);

 return S_OK;

}

 

// ---------------- fire raster event test

void RasterEvent (a long,b long, double, double, char){

 ((CRasterMan*)rasObj)->Fire_OnRasterManEvent(a,b);

}

 

// --------------- set listener test

STDMETHODIMP CRasterMan::SetRasterListener(){

 long handle;

 rasObj =(void*) this; // not nice handled, just for test..

 mdlRaster_eventFunctionSet(RASTER_EVENT,

 &handle,RasterEvent,mdlSystem_getCurrMdlDesc());

 return S_OK;

}

 

HTML client example:

 

<HTML><HEAD>

<SCRIPT LANGUAGE="VBScript">

Sub Button1_OnClick

call raster.SetRasterListener()
 call raster.OpenRaster("d:\img.hmr",0)
End Sub

Sub raster_OnRasterManEvent(a,b)
 MsgBox "Raster from HTML Event"
End sub

</SCRIPT></HEAD>
<BODY>
<object classid="clsid:03D36700-4043-4211-BADC-3450BB0C9080" id="raster" events="true"></object>
<FORM><INPUT NAME="Button1" TYPE="BUTTON" VALUE="Open Raster"></FORM>
</BODY></HTML>
 

Windows Scripting Host (WSH) example

 

<job>
<object progid="RasterObjx.RasterMan" id="raster" events="true"/>
<script language="vbscript">

sub raster_OnRasterManEvent(a,b)
Wscript.echo "Raster from WSH  Event"
end sub

call raster.SetRasterListener()
call raster.OpenRaster("d:\img.hmr",0)
wscript.sleep 5000

</script>
</job>

 

MicroStation v8 VBA

Dim WithEvents msrastObj As RasterMan

...

Set msrastObj = CreateObject("RasterObjx.RasterMan")

Call msrastObj.SetRasterListener

Call msrastObj.OpenRaster("d:\img.hmr",0)

...

Sub msrastObj_OnRasterManEvent(ByVal eventId As Long, ByVal param As Long)

MsgBox "Raster Event from VBA"

End Sub