CSharp D3D sample exception - Forum Open Cascade Technology

Konstantin Chuvilyov
Sun, 09/17/2017 - 16:50

Forums:

Hi! I've got next error on CSharp_D3D sample (prebuilded exe with OCC installation works fine, while manually builded binaries won't work):

System.AccessViolationException: 'Attempted to read or write protected memory. This is often an indication that other memory is corrupt.'

It happens here:

IDirect3DSurface9* D3dColorSurface() { return myD3dSurf; }

on ResizeBridgeFBO(..) method invocation.

I'm using Win10, VS2017, OCC 7.2.0. DirectX SDK is installed.

Any suggestions? Mby I've missed something important to successfully build D3D project?

Kirill Gavrilov
Mon, 09/18/2017 - 09:56

It is difficult to guess what can be a reason, considering that pre-built sample works fine on your configuration, but you may check if you are using consistent OCCT+Sample builds
(e.g. using the same source code, using the same parameters, using the same build mode - Release or Debug, etc.),

Konstantin Chuvilyov
Mon, 09/18/2017 - 15:51

I'm trying to build Debug and Release x64 with no success.

I guess it is not required to install DirectX SDK, because D3D9.lib is used from my WinSDK (Windows Kits\10\Lib\10.0.15063.0).

I've tried to install DirectX SDK and use $(DXSDK_DIR)Lib\x64 path to include lib from this folder - also no success.

Another interesting point is that my size of OCCTProxy_D3D.dll in release mode is 99KB, while size of pre-built dll is 172KB. I guess d3d9.lib is not linked, because I can delete link pragma and successfuly build solution again - no difference in behaviour.

Later I've found next warning message in my build:

Warning LNK4248 unresolved typeref token (0100001A) for 'IDirect3DSurface9'; image may not run OCCTProxy_D3D path_to\OCCTProxyD3D.obj 1

Also I've tried to reinstall opencascade 7.2.0 - no success. I've tried to include <d3d9.h>: build fails on

Error C2061 syntax error: identifier 'THIS'

Platform Toolset v141 (vs2017), Windows SDK version is 10.0.15063.0

Kirill Gavrilov
Mon, 09/18/2017 - 16:09

Also I've tried to reinstall opencascade 7.2.0 - no success.

Platform Toolset v141 (vs2017), Windows SDK version is 10.0.15063.0

I suppose you have built OCCT 7.2.0 using VS2017 by yourself, because official installation package includes only VS2010 builds, which are incompatible with VS2015+?

Konstantin Chuvilyov
Mon, 09/18/2017 - 17:23

Right now I've tried to build with VS2015 toolset v140 - no success. It crashes in the same way.

Kirill Gavrilov
Tue, 09/19/2017 - 09:29

I've built the sample using VS2015 (x64 Debug target) - Visual Studio has automatically upgraded solution -> .NET Framework 4; though it is better switching to 4.5 in project settings due to bugs in older versions of .NET within System.Windows.Interop.D3DImage.
It starts without issues from Visual Studio (msvc_D3D.bat vc14 win64 Debug).
So it should be something in your environment which causes the issue...

Guido van Hilst...
Mon, 09/18/2017 - 19:35

Hi Konstantin,

If you are looking for C# solution to development with Opencascade we have advanced OpenCascade wrappers avalaible.

There a 6 assemblies for each occ module:

CCT.OCDotNet.Foundation.dll
CCT.OCDotNet.ModelingData.dll
CCT.OCDotNet.ModelingAlgorithms.dll
CCT.OCDotNet.Visualization.dll
CCT.OCDotNet.ApplicationFramework.dll
CCT.OCDotNet.DataExchange.dll

Our C# wrappers include:


        //Dynamic casting :
        OCGeom_Plane plane = myFace.Surface() as OCGeom_Plane;


        //Casting to shape type
        OCTopoDS_Face face = myShape.AsFace();

        //Streaming: to any .net stream.
        public static void ShapeToStream(OCTopoDS_Shape shape, Stream stream)
        {
            OCBRepTools.Write(shape, stream);
        }
        public static OCTopoDS_Shape ShapeFromStream(Stream stream)
        {
            OCBRep_Builder builder = new OCBRep_Builder();
            OCTopoDS_Shape shape = new OCTopoDS_Shape();
            OCBRepTools.Read(shape, stream, builder);
            return shape;
        }



        //Extension methods to easy acces the undelaying geometry:
        OCGeom_Curve curve = myEdge.Curve();

        //Extension methods for easy iterating of shapes:
        foreach(OCTopoDS_Edge edge in shape.Edges())
        {
            //...
        }

See online demo build with opencacade C# wrappers:

MakeBottle

If you are interested in the C# wrappers , you can contact me at: guidovanhilst at gmail dot com.

Best regards,

Guido