merge file formats.txt into README.md

Author: minexew

README.md

@@ -2,3 +2,50 @@
 Reverse engineering of Freedom Fighters (2003) and possibly other Glacier engine games
 
 [![screenshot](https://raw.githubusercontent.com/minexew/Freedom/master/_images/render.jpg)](https://raw.githubusercontent.com/minexew/Freedom/master/_images/render.jpg)
+
+## File formats in map data
+
+### BUF
+    - no header
+    - ASCII resource names throughout
+    - identifiers at the end
+    - random data referenced externally?
+    - not present in ErrorMessages
+
+    - contains GMS instance names
+    - contains GMS instance auxiliary buffers (not understood)
+
+### GMS - entities
+    - compressed
+    - cross-refs to PRM - mostly understood, able to render entire scene into .obj
+    - refers to function names (script not figured out yet)
+
+### LOC - hierarchical localization data
+    - fully understood
+    - not present in ErrorMessages
+
+### OCT - ?
+
+### PRM - object geometry
+    - we're able to enumerate models
+    - dump OBJs with correct vertex positions and load those into Blender
+    - doesn't describe model placement in world (see GMS)
+    - a lot of questions remain
+    - doesn't seem to contain world terrain (??)
+
+### RMC - ?
+### RMI - ?
+### SGP - ?
+### SND - ?
+### SUP - ?
+
+### TEX - textures
+    - texdump managed to parse everything we tried
+    - also contains reference to WAV files - this part is not understood
+
+### ZGF - compressed font collection
+    - able to reliably decompress
+    - unable to reliably tell font boundaries
+    - (probably not very interesting)
+
+### xtr - custom format to help mapping file layouts and find gaps in understood data