The spec for javax.swing.plaf.nimbus.NimbusLookAndFeel.getDerivedColor(Color color1, Color color2, float midPoint) says:

     * @param midPoint The offset between color 1 and color 2, a value of 0.0 is
     *                 color 1 and 1.0 is color 2;

Exact second color is not always returned for 1.0 offset value.

Please see the following code sample:

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import java.awt.*;

public class Test {
    public static void main(String[] args) {
        class MyNibusLAF extends javax.swing.plaf.nimbus.NimbusLookAndFeel {
            public Color callGetDerivedColor(Color c1, Color c2, float midPoint) {
                return getDerivedColor(c1, c2, midPoint);
            }
        }
        Color secondColor = Color.BLACK;
        Color returnedColor = new MyNibusLAF().callGetDerivedColor(Color.WHITE, secondColor, 1.f);
        System.out.println("returnedColor = " + returnedColor);
        System.out.println("secondColor = " + secondColor);
    }
}
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Output will look:

returnedColor = javax.swing.plaf.ColorUIResource[r=1,g=1,b=1]
secondColor = java.awt.Color[r=0,g=0,b=0]


Color RGB components are not as expected.
Posted Date : 2009-06-10 13:12:13.0

N/A

I believe this is caused by wrong rounding mode. Conversion to (int) rounds towards zero, whereas we should be rounding towards negative infinity. Math.round() does exactly what we need here.
Posted Date : 2009-06-26 08:27:42.0