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Thread: RGB QColor(QRgb)

  1. #1
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    Default RGB QColor(QRgb)

    I want to create a QColor,I find that QColorcan be created by
    Qt Code:
    1. QColor(int r,int g,int b,int a=255)
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    or by
    Qt Code:
    1. QColor(QRgb color)
    To copy to clipboard, switch view to plain text mode 
    ,Now I have two questions:
    1.if the value of r,g,b is between 0 and 1,how to convert to int? because
    Qt Code:
    1. QColor(int r,int g,int b,int a=255)
    To copy to clipboard, switch view to plain text mode 
    need int parameter?
    2.If I use
    Qt Code:
    1. QColor(QRgb color)
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    to create a color,how to convert (0,1) to tpye QRgb?
    Thk u.

  2. #2
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    Default Re: RGB QColor(QRgb)

    there is QRgb qRgba ( int r, int g, int b, int a ), use it.
    Qt Assistant -- rocks!
    please, use tags [CODE] & [/CODE].

  3. #3
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    Default Re: RGB QColor(QRgb)

    QRgb qRgba ( int r, int g, int b, int a ),which needs int parameter,but I have the value of r,g,b is between 0 and 1? How to convert them to int value?
    thank u.

  4. #4
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    Default Re: RGB QColor(QRgb)

    You have to manually map the values from.
    0..........1

    On

    0..........255

    Then pass the mapped value in qRgba(); I am not good in Mathematics otherwise could have provide you the actual solution.

  5. #5
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    Default Re: RGB QColor(QRgb)

    If you just want to create a QColor from rgb values between 0 and 1, you can also use QColor::setRgbF(). No need to think about
    Qt Code:
    1. (quint8)(value*255)
    To copy to clipboard, switch view to plain text mode 
    and polluting your code with it.
    Horse sense is the thing that keeps horses from betting on people. --W.C. Fields

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  6. #6
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    Default Re: RGB QColor(QRgb)

    thk u.i wil try.

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