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JanetTerra
Jul 4, 2011
=Creating a Nonrectangular Window=
//Janet Terra//
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Creating an irregular shaped window is achieved with WinAPI calls to user32.dll and gdi32.dll. The first step is to create a window without a caption. This can be achieved with the stylebits commands _WS_POPUP in the addbits parameter and _WS_CAPTION in the removebits paramater, or simply using the window_popup style. It is also advisable to keep the window in the forefront. Do this by using the stylebits command _WS_EX_TOPMOST in the extended bits parameter. Remember that any GUI window may be closed with Alt-F4.
For more detailed discussion of stylebits, see [[media type="custom" key="9932065"]].
=Demo 1: Drawing a Nonrectangular Window=
This first demo draws a circle, a rectangle, and some graphic text. The background is never added to the window. Only the actual drawings, including the graphic text, become part of the window. First, open a captionless window.
[[code format="lb"]]
Nomainwin
'Define the Window
WindowWidth = 500
WindowHeight = 500
UpperLeftX = int((DisplayWidth-WindowWidth)/2)
UpperLeftY = int((DisplayHeight-WindowHeight)/2)
graphicbox #ShapeWindow.gb, 0, 0, 500, 500
stylebits #ShapeWindow.gb, 0, _WS_BORDER, 0, 0
'Keep the Shaped Window in the Forefront
stylebits #ShapeWindow, 0, 0, _WS_EX_TOPMOST, 0
open "Shape Window" for window_popup as #ShapeWindow
#ShapeWindow "trapclose [closeShapeWindow]"
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Once the window is opened, handles and device controls to both the window and the graphicbox must be obtained.
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'Obtain the Handles and Device Controls
hBw = hWnd(#ShapeWindow)
hBgb = hWnd(#ShapeWindow.gb)
hDCw = GetDC(hBw)
hDCgb = GetDC(hBgb)
'The Function
Function GetDC(hW)
Calldll #user32, "GetDC", _
hW as ulong, _
GetDC as ulong
End Function
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Now you're ready to draw an image. In this first demo, the image will be drawn using API calls. These are the steps in the [drawShape] gosub.
1: The Destination - Define a region to hold the finished window. Because this region will be built upon, start with all 0's for x, y, width and height.
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'Original values for hRgn is meaningless
hRgn = RectRegion(0, 0, 0, 0)
'The Function
Function RectRegion(ulx, uly, width, height)
CallDLL #gdi32, "CreateRectRgn", _
ulx as long, _
uly as long, _
width as long, _
height as long, _
RectRegion as ulong
End Function
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2: The Circle - Define the x, y, width and height values for the circle. Select a red brush, paint the designated ellipse, delete the brush.
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'hRgn1 = Elliptical Source Region
hRgn1 = EllipticRegion(100, 50, 200, 250)
'Paint the Ellipse Red
brushColor1 = 255 'Red Brush
hBrush1 = createBrush(brushColor1)
Call SelObject hDCw, hBrush1
Call PaintRegion hDCw, hRgn1
Call DelObject hBrush1
'The Functions and Subs
Function RectRegion(ulx, uly, width, height)
CallDLL #gdi32, "CreateRectRgn", _
ulx as long, _
uly as long, _
width as long, _
height as long, _
RectRegion as ulong
End Function
Function EllipticRegion(ulx, uly, width, height)
CallDLL #gdi32, "CreateEllipticRgn", _
ulx as long, _
uly as long, _
width as long, _
height as long, _
EllipticRegion as ulong
End Function
Function createBrush(brushColor)
Calldll #gdi32, "CreateSolidBrush", _
brushColor as long, _
createBrush as ulong
End Function
Sub PaintRegion hDC, hRgn
Calldll #gdi32, "PaintRgn", _
hDC as ulong, _
hRgn as ulong, _
null as long
End Sub
Sub DelObject hObject
Calldll #gdi32, "DeleteObject",_
hObject as ulong,_
null as long
End Sub
Sub SelObject hDC, hBrush
Calldll #gdi32, "SelectObject", _
hDC as ulong, _
hBrush as ulong, _
null as long
End Sub
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Use CombineRgn to add this painted region, hRgn1, to the destination region, hRgn.
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'Set hRgn to the Combination of itself and hRgn1
newRgn = CombineRgn(hRgn, hRgn, hRgn1, _RGN_OR)
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Now that region hRgn1 is a part of region hRgn, it is no longer needed. Delete that object to free memory.
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'Delete hRgn1
Call DelObject hRgn1
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3: The Rectangle - Define the x, y, width and height values for the rectangle. Select a blue brush, paint the designated rectangle, delete the brush.
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'hRgn2 = Rectangular Source Region
hRgn2 = RectRegion(150, 75, 300, 200)
'Paint the rectangle blue
brushColor2 = 255 * 256^2 'Blue Brush
hBrush2 = createBrush(brushColor2)
Call SelObject hDCw, hBrush2
Call PaintRegion hDCw, hRgn2
Call DelObject hBrush2
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Once again, use the API Call CombineRgn to add the pixels of the rectangle hRgn2 to the final destination region hRgn.
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'Set hRgn to the Combination of itself and hRgn2
newRgn = CombineRgn(hRgn, hRgn, hRgn2, _RGN_OR)
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The hRgn2 rectangle can now be safely deleted to free up space, as it's been added to the shaped window region hRgn.
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'Delete hRgn2
Call DelObject hRgn2
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4: The newly built region made up of regions hRgn1 and hRgn2 can now be set as the window.
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'Set hRgn as the Window
Call SetWindowRgn hBw, hRgn, 1
'The Sub
Sub SetWindowRgn hWnd, hRgn, redrawMode
Calldll #user32, "SetWindowRgn",_
hWnd as ulong,_
hRgn as ulong,_
redrawMode as boolean,_
SetWindowRgn as long
End Sub
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The SetBkMode of #gdi32 can be called to achieve a transparent background for text. Text can then become part of the window.
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'Set background to Transparent
Call SetBkMode hDCgb, 1
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ReleaseDC is again called to release memory.
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'Release memory
Call ReleaseDC hBgb, hDCbg
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Graphics text is accomplished with native Liberty BASIC code.
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'Format Text
#ShapeWindow.gb "font Courier_New 14 Bold"
#ShapeWindow.gb "color Black; place 120 150"
#ShapeWindow.gb "\Alt-F4 to Close"
Wait
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Run your program and a shaped window appears. Close the window with Alt-F4 or include a button for closure. The window will stay on top of other windows, but it is possible for the window to lose focus. If this happens, click on the window before pressing Alt-F4.
[[image:combineRgnPic.gif]]
Click [[media type="custom" key="9932365"]] for the entire program.
=Third Part Title=
Text here.
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'code here
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