Vertices are points on a map at which two or more linedefs are joined. They have no properties other than their position. No two vertices may be coincident. Extra vertices are generated in the process of nodebuilding, but this is normally transparent as map editors remove them when a map is opened.
The vertices of a map are stored in the
VERTEXES lump as a list. Each vertex has a 4-byte entry consisting of the following:
|0-1||Signed 16-bit integer||X position|
|2-3||Signed 16-bit integer||Y position|
Since the positions are stored as signed 16-bit integers, they can range from -32768 to 32767.