title: Drawing pixels with XCode
body: <p>I am trying to draw individual pixels in xcode. 
  I already know Objective-C but not the Quartz/graphics stuffs and I'nm not interested at the moment. I simply want a basic app that let me have a map of X*Y and being able to show pixel at (x,y) with color rgb.</p>
  
  <p>I don't know how to find a tutorial for this, and I think it must be very quick. Do you guys have a file like this, or could point me to a tutorial?
  Any help is greatly appreciated.</p>