>>>>I have an app where I am cropping images. Everything works great thanks to GdiPlusX. I create a shape object with MouseDown / MouseMove to mark the crop area. My question is how to get the contrasting color so the shape border will show against all the different colors in the image. I know I can get the color at the mouse down point but how do I get a light color if the image is dark, etc. I assume this is an easy one if you know what you are doing.
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>>>What if you use XOR operation to draw the selection box border?
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>>I looked at that but how would I use it. I have one value; the current color. What would be the 2nd value?
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>Try
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>lnNewColor = BITXOR(lnCurrentColor, 0xFFFFFFFF)
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It turns out that since an image can have any color at any point that I needed to check around the area of the crop box. I am now looking at the starting 4 corners and changing the color based on the majority color. Also I found that white is best overall for the box outline so I am testing for the brightness at the 4 corners. If it is very bright then I use black. As Dragan pointed out, using the contrasting color does not work if you have a mid range color. It would be wonderful if I could change the color at each point on the shape border but I fear that is beyond the capabilities of VFP, at least without drawing and re-drawing every point individually.

Thanks to everyone for the suggestions.