What exactly do these two points emanating rays represent? Is it simply the direction of light bouncing off of the pipe and the bottom of the coat?

I'm a bit confused about this graphic, as the person is not directly emitting light. Do the rays represent the light they are reflecting?

For objects that don't really emit light, is the number of photons that they emit similar? What causes those variations?

This slide, while primarily illustrating the concept of flux and the density of photons on a sensor, reminds me of the double-slit experiment lol. I'm curious if there are properties that capture the experimentally induced wave hypothesis of light behind a 'double slit'

I wonder how the size of the sensor affects the aspects of the image you're trying to capture

To respond to theflyingpie I am pretty sure it is as you described. And is just the light bouncing off of the respective points.

Is this related to the double slit experiment