GraphicsPath AddLine creates unexpected path

Question

I am trying to draw a "folder" like image using a GraphicsPath.

My function to create the path is the following:

Public Function FolderRect(ByRef r As Rectangle) As System.Drawing.Drawing2D.GraphicsPath

    Dim p As New System.Drawing.Drawing2D.GraphicsPath

    Dim iTabWidth As Integer = 30
    Dim iTabHeight As Integer = 12

    With p
        Call p.AddLine(r.Left, r.Top, r.Left + iTabWidth, r.Top)
        Call p.AddLine(r.Left + iTabWidth, r.Top, r.Left + iTabWidth, r.Top + iTabHeight)
        Call p.AddLine(r.Left + iTabWidth, r.Top + iTabHeight, r.Right, r.Top + iTabHeight)
        Call p.AddLine(r.Right, r.Top + iTabHeight, r.Right, r.Bottom)
        Call p.AddLine(r.Right, r.Bottom, r.Left, r.Bottom)
        Call p.AddLine(r.Left, r.Bottom, r.Left, r.Top)

        Call p.CloseFigure()
    End With

    Return p

End Function

The code looks right to me, but the result is not what I expected:

(I created the "correct" version using an image editor).

May this be a bug in the GraphicsPath?

This is what the PathPoints look like:

This is what "r" looks like:

I misread. I thought you were after the angled/beveled look. If I use your code I get square tabs. I dont see how that will create bevels — Ňɏssa Pøngjǣrdenlarp, Jan 28 '16 at 23:29
Try it by drawing the last lines instead of the p.CloseFigure() it may not be closing it the way you expect. — Derek Tomes, Jan 29 '16 at 00:33
@Plutonix Do you still have your "angled" code? I would really like to use it. Unfortunately you removed it. — Maiken Roskilde, Jan 29 '16 at 09:34
@DerekTomes Removing p.CloseFigure() did not change anything. — Maiken Roskilde, Jan 29 '16 at 09:47
I removed it because I read the question wrong/posted a non answer. I would examine the PathPoints in the paintevent - because those points are correct. Maybe you have an overload which bevels the tab? — Ňɏssa Pøngjǣrdenlarp, Jan 29 '16 at 13:31

score 0 · Answer 1 · answered Jan 28 '16 at 22:34

0

The graphics path is almost certainly correct. You can verify this by looking at the PathPoints property of the graphics path.

It's possible that there is some roundoff error when you draw the graphics path. Try making the path the same size as the target bitmap.

answered Jan 28 '16 at 22:34

xpda

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I can not make the path the same size of the target bitmap. I have added a screenshot of the PathPoints. Do you think it might be correct? – Maiken Roskilde Jan 28 '16 at 23:16
The pathpoints you show do not have an angled line. You might change tabwidth to be a little bit larger or smaller to see if that improves things. – xpda Jan 29 '16 at 04:54
Changing the tabwidth did not change anything. – Maiken Roskilde Jan 29 '16 at 09:53

GraphicsPath AddLine creates unexpected path

1 Answers1