That involves the scientific process of how our brains comprehend three-dimensional imagery.
<u>The mood of this passage is GLOOMY AND MELANCHOLY.</u>
The prevailing emotion or mood found in the excerpt is gloomy/melancholy. This is clear when we pay attention to the author's approach to the main character and the overall setting: the character wakes up in impenetrable "blackness", there's no sound but the wind in the "blackened trees", he stood on a "cold autistic dark", and so on and so forth. All the setting is filled with darkness, there is nothing that evokes to something cheerful or enjoyable and the character is pensive in the middle of all that.
