[Defect?] ObjectAttributes.PlotWeight has no effect – even with PlotWeightSource = PlotWeightFromObject

Rhino Developer
, ,
1

I wonder why setting the PlotWeight property has no effect. Positive and negative values always display the standard point, whereas the color can be changed. I set both the PlotWeightSource as well as the ObjectColorSource. See code below:

Code

    protected IEnumerable<Guid> DrawSnappingPoints (Point3d[] points, double weight)
    {
        var attributes = new ObjectAttributes();
        attributes.ObjectColor = System.Drawing.Color.Yellow;
        attributes.ColorSource = ObjectColorSource.ColorFromObject;
        attributes.PlotWeight = weight;
        attributes.PlotWeightSource = ObjectPlotWeightSource.PlotWeightFromObject;
        
        return Doc.Objects.AddPoints(points, attributes);
    }
    DrawSnappingPoints (myPoints, 400.0);
    DrawSnappingPoints (myPoints, -1.0);

The screenshot shows the default point weight but with the custom yellow color:

Objective

My objective is to display snapping points during a GetPoint/GetTransform. To do so, I’d add points to the document before the GetPoint.Point() call and remove them after this call.
If this is a poor strategy in the first place I would be happy to receive further ideas. I try to avoid drawing the points in the DynamicDraw event as I already render quite a lot.

##My system
Rhino for Mac 5.3.1
Mono 4.8.0

2

Have you run the PrintDisplay command?

– Dale

3

@dale Yes, I ran _PrintDisplay with State=On, Color=Print and also Color=Display.
Under ViewPorts I did not enter anything. Should I?

4

It is never a good strategy to add temporary geometry to the document in a command or in a object/point picking operation.

You should always try to dynamically draw your temporary geometry using a conduit or on GetPoint.OnDynamicDraw callback.

Specifically to your problem, point objects do not use print weight (or thickness). This is why the points are not fatter.

But in a dynamic drawing operation, you can draw fatter points.

protected override void OnDynamicDraw(GetPointDrawEventArgs e)
{
  foreach (var pt in m_points)
    e.Display.DrawPoint(pt, PointStyle.ControlPoint, 3, m_color);
  base.OnDynamicDraw(e);      
}
1 Like
5

thank you, exactly what I needed.
Initially, I was worried that it would be too slow because redraws on every mouse move but it turned out just fine.

6

unfortunately, also the radius argument for Display.DrawPoints does draw fatter points. Is don’t think this is intended, right?

myGetPointCommand = (object sender, GetPointDrawEventArgs e) => e.Display.DrawPoints(SnappingPoints, Rhino.Display.PointStyle.X, 80, System.Drawing.Color.Blue);
7

I am not sure I understand the question. Can you explain further?

8

Sorry, forgot a word. The argument int radius does not change the weight of the points for me. I guess it is it a defect indeed. The following two calls unexpectedly produce the same result:

e.Display.DrawPoints(pointArray, Rhino.Display.PointStyle.X, 1, System.Drawing.Color.Blue);
e.Display.DrawPoints(pointArray, Rhino.Display.PointStyle.X, 100, System.Drawing.Color.Blue);

The reason why I would want different weights is that I would like to have a white border around the blue points. So I thought I’d

  1. draw white points with a weight w
  2. draw blue points with a weight w – delta

Is this a viable strategy? Is there another way to achieve this while the Display.DrawPoints() is not working as expected?

9

If you specify a point style of Rhino.Display.PointStyle.X, then the radius parameter is ignored and a fixed radius of 3 is used. Thus, if you want to control the radius, choose an different point style.