BergChristian
commented
3 years ago Sharing my solution if there is non built in to draw arrow heads at the end of a line. (here is the link to the author of it: https://stackoverflow.com/questions/43527894/drawing-arrowheads-which-follow-the-direction-of-the-line-in-pygame/43529178)
Private Sub DrawArrow(g As D2DGraphics, startp As D2DPoint, endp As D2DPoint) Dim dX As Single = endp.x - startp.x Dim dY As Single = endp.y - startp.y
'//vector length
Dim vLen As Single = Math.Sqrt(dX * dX + dY * dY) ' // use Hypot If available
'//normalized direction vector components
Dim udX As Single = dX / vLen
Dim udY As Single = dY / vLen
'//perpendicular vector
Dim perpX As Single = -udY
Dim perpY As Single = udX
'//points forming arrowhead
'//with length L And half-width H
'arrowend = (end)
Dim L As Single = 20
Dim H As Single = 10
Dim leftX As Single = endp.x - L * udX + H * perpX
Dim leftY As Single = endp.y - L * udY + H * perpY
Dim rightX As Single = endp.x - L * udX - H * perpX
Dim rightY As Single = endp.y - L * udY - H * perpY
Dim po(2) As D2DPoint
po(0).x = endp.x
po(0).y = endp.y
po(1).x = leftX
po(1).y = leftY
po(2).x = rightX
po(2).y = rightY
Using brh As D2DBrush = g.Device.CreateSolidColorBrush(D2DColor.FromGDIColor(Forecolor))
g.FillPolygon(po, brh) '(Color.FromArgb(180, RegionColor)))
End Using
'g.DrawPolygon(po, D2DColor.FromGDIColor(Forecolor), 1)
End Sub
jingwood
Hi again!
Testing extensively and ran into a question.
Draw arrows at the end or beginning of a line? Is that supported or do I have to draw them myself as triangles?
I am still amazed how easy this library is to use to get crazy much more performance. Thanks for creating it!
Christian