.ymap

.ymap is compressed file format which is used as map system placement. Since GTA5, this format has XML structure.

CMapData

CMapData is a parent section. It includes file description, flags and entities

<name> </name> 
 

This tag is used to put the name of ymap file. e.g:

<name>bt1_01</name>

File must be named as bt1_01.ymap

<parent></parent>

Parent section is used to link _strm, _long or other subfiles to the main ymap file. Main ymap file links to .ytyp file that include LOD objects only.

<parent>bt1_lod</parent>

It links bt1_01.ymap to bt1_lod.ytyp.

<Flags Value> 

It's unknown what flags do. Some external formats uses value "2" and other - "0".

<entities>

This section enumerate objects and sections in ymap file.

<CEntityDef>

     <archetypeName> - Model name hash
     <flags value/> - Flag object
     <guid value>
     <position x="" y="" z=""> - object coordinates
     <rotation x="" y="" z="" w=""> - object rotation
     <hash_9CA32637> - unknown
     <hash_10FB7C42> - unknown
     <parentIndex value="" /> - Lod Index (?)
     <lodDist value="" /> - Lod Distance
     <hash_CA974BCD> - unknown
     <hash_6C8F1715> - unknown
     <hash_A687AC89> - unknown
     <hash_2691F019> - unknown

<extensions>

This subsection includes other additional sections.

<CExtensionDefLightEffect>

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