GDI+ Multi-Colored gradient brush on lines?

[Biatu]

I have been having trouble with making lines using gdi+ that have 3 color gradients. is this even possible? and if so could I please get any pointers?

Thanks guys

[UEZ]

Is 

_GDIPlus_LineBrushSetPresetBlend()  

what you looking for?

Br,

UEZ

Edited April 5, 2014 by UEZ

[Biatu]

Is 

_GDIPlus_LineBrushSetPresetBlend()  

what you looking for?

Br,

UEZ

Sort of, But how do I draw a line with that? the example shows a rect, but rect does not have a FromXY ToXY. And line draw uses a pen and not a brush.

Thanks again

Edit:

Basically what im trying to do is draw a thick line from point A to point B and have a gradient from the center of the line to the outer, and then fade into transparency.with the edge.

Like this but with multiple colors...

Edited April 6, 2014 by Biatu

[UEZ]

The link to the image is broken but you mean something like this here?
 

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#include <GDIPlus.au3>
#include <GUIConstantsEx.au3>

Example()

Func Example()
    _GDIPlus_Startup() ;initialize GDI+
    Local Const $iWidth = 600, $iHeight = 300, $iBgColor = 0x303030 ;$iBgColor format RRGGBB

    Local $hGUI = GUICreate("GDI+ example", $iWidth, $iHeight) ;create a test GUI
    GUISetBkColor($iBgColor, $hGUI) ;set GUI background color
    GUISetState(@SW_SHOW)

    Local $hGraphics = _GDIPlus_GraphicsCreateFromHWND($hGUI) ;create a graphics object from a window handle
    _GDIPlus_GraphicsClear($hGraphics, 0xFF303030)
    _GDIPlus_GraphicsSetSmoothingMode($hGraphics, $GDIP_SMOOTHINGMODE_HIGHQUALITY) ;sets the graphics object rendering quality (antialiasing)

    Local $iX1 = 20, $iX2 = 580, $iY1 = 200, $iY2 = 200
    Local $hBrush = _GDIPlus_LineBrushCreate($iX1, $iY1, $iX2, $iY2, 0, 0, 1) ;create line brush

    Local $aInterpolations[5][2] ;define the interpolated colors and positions
    $aInterpolations[0][0] = 4
    $aInterpolations[1][0] = 0x7FFF0000 ;Red
    $aInterpolations[1][1] = 0 ;0% from the left
    $aInterpolations[2][0] = 0xFF00FF00 ;Green
    $aInterpolations[2][1] = 0.40 ;To 40% from the left
    $aInterpolations[3][0] = 0xFF0000FF ;Blue
    $aInterpolations[3][1] = 0.60 ;To 60% from the left
    $aInterpolations[4][0] = 0x7FFFFF00 ;Yellow
    $aInterpolations[4][1] = 1 ;To 100% from the left

    _GDIPlus_LineBrushSetPresetBlend($hBrush, $aInterpolations) ;set the linear gradient brush colors and position

    Local $hPen = _GDIPlus_PenCreate2($hBrush, 8)

    _GDIPlus_GraphicsDrawLine($hGraphics, $iX1, $iY1, $iX2, $iY2, $hPen)

    Do
    Until GUIGetMsg() = $GUI_EVENT_CLOSE

    ;cleanup GDI+ resources
    _GDIPlus_PenDispose($hPen)
    _GDIPlus_BrushDispose($hBrush)
    _GDIPlus_GraphicsDispose($hGraphics)
    _GDIPlus_Shutdown()
    GUIDelete($hGUI)
EndFunc   ;==>Example

Br,

UEZ

[Biatu]

The link to the image is broken but you mean something like this here?

 

expandcollapse popup

#include <GDIPlus.au3>
#include <GUIConstantsEx.au3>

Example()

Func Example()
    _GDIPlus_Startup() ;initialize GDI+
    Local Const $iWidth = 600, $iHeight = 300, $iBgColor = 0x303030 ;$iBgColor format RRGGBB

    Local $hGUI = GUICreate("GDI+ example", $iWidth, $iHeight) ;create a test GUI
    GUISetBkColor($iBgColor, $hGUI) ;set GUI background color
    GUISetState(@SW_SHOW)

    Local $hGraphics = _GDIPlus_GraphicsCreateFromHWND($hGUI) ;create a graphics object from a window handle
    _GDIPlus_GraphicsClear($hGraphics, 0xFF303030)
    _GDIPlus_GraphicsSetSmoothingMode($hGraphics, $GDIP_SMOOTHINGMODE_HIGHQUALITY) ;sets the graphics object rendering quality (antialiasing)

    Local $iX1 = 20, $iX2 = 580, $iY1 = 200, $iY2 = 200
    Local $hBrush = _GDIPlus_LineBrushCreate($iX1, $iY1, $iX2, $iY2, 0, 0, 1) ;create line brush

    Local $aInterpolations[5][2] ;define the interpolated colors and positions
    $aInterpolations[0][0] = 4
    $aInterpolations[1][0] = 0x7FFF0000 ;Red
    $aInterpolations[1][1] = 0 ;0% from the left
    $aInterpolations[2][0] = 0xFF00FF00 ;Green
    $aInterpolations[2][1] = 0.40 ;To 40% from the left
    $aInterpolations[3][0] = 0xFF0000FF ;Blue
    $aInterpolations[3][1] = 0.60 ;To 60% from the left
    $aInterpolations[4][0] = 0x7FFFFF00 ;Yellow
    $aInterpolations[4][1] = 1 ;To 100% from the left

    _GDIPlus_LineBrushSetPresetBlend($hBrush, $aInterpolations) ;set the linear gradient brush colors and position

    Local $hPen = _GDIPlus_PenCreate2($hBrush, 8)

    _GDIPlus_GraphicsDrawLine($hGraphics, $iX1, $iY1, $iX2, $iY2, $hPen)

    Do
    Until GUIGetMsg() = $GUI_EVENT_CLOSE

    ;cleanup GDI+ resources
    _GDIPlus_PenDispose($hPen)
    _GDIPlus_BrushDispose($hBrush)
    _GDIPlus_GraphicsDispose($hGraphics)
    _GDIPlus_Shutdown()
    GUIDelete($hGUI)
EndFunc   ;==>Example

Br,

UEZ

Ah, yes thank you very much. didn't see PenCreate2. I will just need to adjust _GDIPlus_LineBrushCreate to make the grad vertical, which ive done experimenting with the Rect version in the help file.