A guided, or "right angle" glide is one in which there are two perpendicular walls, with 32 units of space between them (e.g. doom2 map16). In order for the glide to succeed, the player must simply align their angle with the space and use forward mouse sensitivity to push themselves through.A flat faced glide is one in which both edges of the glide are flat, and the player must align himself both angularly, and positionally precisely in the middle of the gap (e.g. doom2 map02). This variety is rarely done in non tool-assisted speedruns due to the fact that such glides often have monsters in close proximity which can ruin the player's attempts at positioning.