_Clearcolor and _setalpha day request

_Clearcolor and _setalpha day request - Printable Version

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_Clearcolor and _setalpha day request - TempodiBasic - 04-29-2025

Hi

I go through _Clearcolor and _Setalpha keywords starting from this thread _Clearcolor _Setalpha and transparency and I got more informations about these two QB64pe keywords, but I find some informations uncomplete so I ask, if there is a large interest of community members, a more detailed informations.
For my interest for now I'm stuck on how define the range of colors to work on with _Setalpha, in the syntax I can read

Quote:range of color values color1& TO colour2& to set the transparency

moreover please I request to ajust the 3rd example of wiki page of _Clearcolor

1 it is better clear the screen with a color to be more evident the transparency of background of image loaded
2 it need to add _CLEARCOLOR clr~&, NewImage1& after setting alphachannel to keep transparent the background previously made so

here the wikicode with the above corrections

Code: (Select All)



mainscreen = _NewImage(640, 480, 32) ' Main Screen (viewable)

Screen mainscreen

_ScreenMove _Middle

Image1& = _LoadImage("qb64_trans.png") '<<<<<< any image with one background color to clear



If Image1& < -1 Then 'check loaded image handle value before using!

    _Source Image1&

    clr~& = Point(0, 0) 'get background color from image source

    _ClearColor clr~&, Image1& 'clear background color of loaded image

    NewImage1& = _NewImage(_Width(Image1&), _Height(Image1&), 32) 'new image page

    _PutImage , Image1&, NewImage1& 'put image without background color on new page

    _FreeImage Image1& 'free loaded image from memory

End If

_Dest mainscreen:



a& = 0: d = 1

Do

    _Limit 10 'regulate speed of fades

    Cls

    a& = a& + d

    If a& = 255 Then d = -d 'reverse fade

    _SetAlpha a&, , NewImage1& 'sets alpha level of all colors to fade image page in/out

_ClearColor clr~&, NewImage1& 'clear background color of loaded image 

_PutImage (0, 342), NewImage1&

    Locate 1, 1: Print "Alpha: "; a&

    _Display

Loop Until a& = 0

End

Thanks for so beautyful keywords... more technical informations come time by time from developers' team to users like me

Long live to QB64pe!