Annotating 2D entities in 3D models - e.g. Step AP 203 ed2 GD&A

Oh, and just to be clear: I just want some textual annotations, no real tolerance annotations needed.

Dear Thomas, OCCT provides a way to associate additional data with shapes through OCAF in general, and in particular XDE component (please, see its user's guide) provides a way to define assemblies and associate names, colors, and other data to shapes. These data can be exported to / imported from STEP. There is also minimal support of GD&T (dimensional tolerances, not annotations), but this has not yet been documented in the user's guide.

Dear Thomas,

some time ago I had to implement GD&T visualization using OCCT (GD&T / FT&A - whatever you call them - come from an external source/file using a 3rd party product). The solution I ended up with was to use the XDE assembly structure for the geometrical data. The annotations were stored separately using OCAF. Unfortunately, I had to store the shapes the annotations refer to separately (i.e. redundantly). There were two reasons for that:

1. It is possible to attach data to individual geometrical features of TopoDS_Shapes in XDE (like colors), I guess, but this is not well documented and I could not find any samples. So it was necessary to dig through the OCCT code, which isn't that easy.

2. The current implementation of XDE has some problems: visualization of 'free shapes' get recomputed very often so it was of advantage to store the annotated faces/edges separately in order to be able to manage (show, highlight etc.) them without having to cope with the recomputation of the visualization.

Hope this helps
Pawel

Thanks to both of you for your replies!
So it seems possible but probably requires some work(around). I found the documentation for Step and XDE (https://bitbucket.org/sboz/wendel/src/df14a63bb6a2c421cba54f3183d85a1765...) and will read through it. I am especially interested in what data can be stored using XDE. I will definitely need assemblies and associate names plus textual annotations of 2D entities.

@Pawel: In what form did you store the separately stored entities (faces/edges incl. annotations) and how did you merge it with the geometrical data? I do not need an exact description, just a pointer in the right direction.

Agian, thanks for all further replies!

Thomas

Hi,

I am trying to display annotation at sharp connected face edge. I would like to display image annotation I have attached the annotations.png

Is it possible to have some special characters in image format to imbed in OCC annotation. Or is there any we can just mention the image path to show the special annotations.

Thanks,

Dinesh

Hi,

I am using Graphic3d_AspectText3d to display text annotation. I am facing some issues when we do zoom-in  and zoom-out I am not able to see annotations and the size of the annotations as well not appropriate. Please see below code snippet of display text annotation.

Please let me know if I am doing a correct thing or is there anything missing. Thanks in advance.

Thanks,

Dinesh

///////////////

TextInfo as defined as below,

TextInfo textInfo = new SXTextInfo();
textInfo.Color = QuantityNameOfColor.Quantity_NOC_MAGENTA1;
textInfo.IsZoomable = false;
textInfo.Height = textInfo.Height/10.0;
textInfo.TextFontAspect = TextFontAspect.Font_FA_Bold;
textInfo.TextPath = Graphic3dTextPath.Graphic3d_TP_UP; 

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

       public void DisplayTextAnnotation(string text, double[] location, TextInfo textInfo)
        {
            Quantity_NameOfColor color = (Quantity_NameOfColor)textInfo.Color;
            Aspect_TypeOfStyleText aspectStyle = (Aspect_TypeOfStyleText)textInfo.AspectStyle;
            Graphic3d_HorizontalTextAlignment horizontalTextAlignment = (Graphic3d_HorizontalTextAlignment)textInfo.HorizontalAlignment;
            Graphic3d_VerticalTextAlignment verticalTextAlignment = (Graphic3d_VerticalTextAlignment)textInfo.VerticalAlignment;
            Graphic3d_TextPath textPath = (Graphic3d_TextPath)textInfo.TextPath;

            Graphic3d_AspectText3d aTextAspect = new Graphic3d_AspectText3d();
            aTextAspect.SetTextZoomable(textInfo.IsZoomable);
            aTextAspect.SetColor(new Quantity_Color(color));
            aTextAspect.SetTextAngle(textInfo.Angle);
            aTextAspect.SetFont(textInfo.Font);
            aTextAspect.SetStyle(aspectStyle);

            Graphic3d_Group textGroup = Prs3d_Root.CurrentGroup(prsPartNamePresentation);
            textGroup.SetPrimitivesAspect(aTextAspect);

            Graphic3d_Vertex aPoint = OCCConvertor.Graphic3d_Vertex(location);
            textGroup.Text(text, aPoint, textInfo.Height, textInfo.Angle, textPath, horizontalTextAlignment, verticalTextAlignment, true);            
        }