Dark Places supports the following formats:

[Source : Quake wiki.net]

mdl - vertex animated model with skin texture inside it, can contain multiple skins, can contain self-animating framegroups, low quality animation

md2 - vertex animated model with a single external texture reference, very low quality animation

md3 - vertex animated model with multiple texture references (multiple meshes), limited coordinate space

zym - skeletal animated model with multiple texture references (multiple meshes), no smooth skinning (each vertex is linked only to one joint), high quality animation.

dpm - skeletal animated model with multiple texture references (multiple meshes), smooth skinning supported, high quality animation.

iqm - skeletal animated model with multiple texture references (multiple meshes), smooth skinning supported, high quality animation, smallest files. More information: http://lee.fov120.com/iqm/

psk - skeletal animated model with multiple texture references (multiple meshes), smooth skinning supported, high quality animation. This format is commonly associated with UnrealEngine, in DarkPlaces it can only load one .psa file of the same name as the .psk file, so multiple animation files are not possible (however multiple animations can exist in one .psa file).

obj - non-animated static model, large files, easy to export.

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Noesis is a tool for previewing and converting various model formats, so that may be able to help you too.

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this was very helpful, thankyou