Definitely not what actually happens. The camera sensor is made up of millions of individual pixels (hence 'mega pixel'), and each one of those is an actual light sensor that send information to the processor. Each pixel has an assigned location on the grid, and the processor takes all that information and puts together an image from that. There's no guesswork done by any part of the system. The processor interprets the value of signal from each pixel, and translates that into a color band, that then turns into a color pixel on the photo. Just because analog light hits the sensor doesn't mean it's an analog sensor. The only analog sensor is film. Think of an insect eye analogy - each pixel is one of those individual elements of the insect eye.
Here's some sample reading that explains a bit how sensors work:
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