Spectrum Analyzer [003]

My original, ill-conceived notion for drawing a waterfall display was to do a bunch of CGContextFillRect() each drawing a 1x1 rectangle. 1024 pixels wide * 250 pixels tall * redraw-rate = millions of 1x1 rectangles per second. Yeah, that didn't work at all.

So, I made a second internal representation of the waterfall that was just a bunch of uint32_t's representing the RGBA values of the graph and treated it like an image and let Core Graphics render it directly. So much faster.

Now I need to find an HF satellite that's actively transmitting while passing overhead so I can see doppler shift in action. Or maybe I can just load all of the equipment in a car and drive towards a radio station really fast.