Oval radial gradients

Radial gradients are filled by moving a circle along a line, while changing its color. They look nice but a bit too 'circly' for my tastes, and I couldn't figure out how to squash them. Turns out it's really simple !, as the points you use to define them obey the same rules as any other primitive : they're transformed by the view matrix. Use CGContextScaleCTM(context, 1, someSquashValue) then draw as usual with CGContextDrawRadialGradient.

Image:Radial gradients.png

This will squash your gradient's circle and its height, so you'll need to compensate CGContextDrawRadialGradient's startCenter and endCenter. Once there, you can draw a really nice radial background.

Sample code on Radial Gradients as Backgrounds.

2008 10 29

Thank you, exactly what I was looking, for, too. :-)

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