dashed lines

[Chris Holbrook]

Graphics is not my strong suit.

Using a pen with the %PS_DASH style is only good for narrow (1 unit) dashed lines which look terrible when not vertical or horizontal. Also, the "missing" parts of the dashed line appear to have a white background, whereas the background across which they are drawn is grey.

So, how do I draw a thicker dashed line? would it have to be a series of rectangles (sounds like hard work!), and how can I set the correct color for the gaps in the lines, please?

[Dominic Mitchell]

Unfortunately, you are using a cosmetic pen which draws dotted or dashed
lines using a width of one pixel. That is, the width parameter is ignored.
You need to use a geometric pen. The bad news, for you I guess, is that you
cannot use the DDT graphics command for this.

So break out the champagne, it's gonna be SDK.

  LOCAL tps       AS PAINTSTRUCT
  LOCAL tlb       AS LOGBRUSH
  LOCAL hPen      AS DWORD
  LOCAL hPenOld   AS DWORD

  BeginPaint hWnd, tps

  ' Draw a 3-pixel width dashed line at an angle
  tlb.lbStyle = %BS_SOLID
  tlb.lbHatch = 0
  tlb.lbColor = &H00C0C0C0???   ' gray

  hPen = ExtCreatePen(%PS_GEOMETRIC OR %PS_DASH OR %PS_ENDCAP_FLAT OR %PS_JOIN_MITER, 3, tlb, 0, BYVAL %NULL)

  hPenOld = SelectObject(tps.hdc, hPen)
  MoveToEx tps.hdc, 0, 10, BYVAL %NULL
  LineTo tps.hdc, 300, 100

  DeleteObject SelectObject(tps.hdc, hPenOld) 
  
  EndPaint hWnd, tps

[Chris Holbrook]

Pukka!

Thanks Dominic!