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  1. Qt
  2. QTBUG-13843

Add QColor::isOpaque() method

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Details

    • Suggestion
    • Resolution: Unresolved
    • P3: Somewhat important
    • Some future release
    • 5.11.0 RC 1
    • GUI: Painting
    • None

    Description

      From QBrush::isOpaque():

      ... The alpha component of the color() is 255 ...

      This is wrong. When I use setAlphaF(0.999) then alpha() will be == 255, but the color is not opaque, because QColor (currently) stores in 16 bit precision.

      I could use alphaF() but that would require a conversion from qreal to int (implying a floating point division), which is slower then the integer access method.

      A function QColor::isOpaque() which would just compare the alpha member to 65535 would be nice.

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          replaces

          Bug - A problem which impairs or prevents the functions of the product. QTBUG-13225 qtdemo on windows: Failed to launch the example (Spectrum Analyzer)

          • P3: Somewhat important - Should be fixed, but doesn't affect the release in any way.
          • Closed
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              Unassigned Unassigned
              cfeck Christoph Feck
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              Dates

                Created:
                Updated:

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