grayscale night

I stumbled through the dark after turning the light off. I fell into the bed, laid on my back, stared at the ceiling. As my eyes adjusted to the darkness, I began measuring the angles of objects in the room in my head. My mind was going 90 miles an hour, estimating the dimensions including chamfer radii on furniture. I started plotting points on axis of X, Y, and Z. The room faded to grayscale. All I could focus on was the luminosity of the room…the way the light from the moon crept in through the window. I laid there, glancing at the alarm clock. In my head the grays in the room were translated into percentages of opacity of black...God, one too many 3D classes or something. I have this weird thing with calculations lately. What’s up with that? I mean, I always kind of sucked at math.