MDL (GoldSrc)
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Important:Older versions of StudioMDL, including the version found in the
Half-Life SDK on Steam, do not support tiling UVs, clamping them to the edge of the texture. This is not a limitation of the HLMDL file format; the Sven Co-op StudioMDL can create MDLs compatible with vanilla
GoldSrc which have tiled UVs.
Bug:The latest version of the Sven Co-op StudioMDL (from December 2020), as found in the Sven Co-op SDK, has some bugs with bounding boxes; use the version linked above instead (from November 2018). [todo tested in ?]
Tip:To create a model or submodel with more than 4080 tris, split the model into multiple SMD meshes, with a separate $body or $bodygroup entry for each mesh in the QC file.
Warning:Avoid going over 9000 tris!
While the HLMDL format can handle over 100K tris, the old OpenGL renderer struggles with such "high-poly" models, even on high-end GPUs.[1]
Note:Third party games that upgrade the renderer (ex:
,
or
) can handle higher polygon MDLs better. This does not include
Sven Co-op, which uses a mostly vanilla renderer.
This is obviously not a problem for games on engines much newer than
GoldSrc that use the HLMDL format, such as
Codename: Loop (
) or
FreeCS (
).
Confirm:Is this soft limit 9000 total, or 9000 being displayed simultaneously?
Confirm:Can custom renderers without engine access, such as Trinity Engine, improve performance for higher-poly MDLs?
Code:While MDL does not natively support animated textures, a model's skin can be quickly switched between in game code to animate between them. For example, monster_houndeye uses skin switching to blink.
Confirm:Max textures, max skins, and other limits?
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MDL (sometimes referred to as Half-Life MDL or HLMDL) is a model format used by GoldSrc to store dynamically lit models which can be animated using skeletal animation, along with their associated textures. It is a heavily modified version of the Quake MDL format.
Overview
Limits
HLMDL has the following limits per input SMD:
- 1 mesh
- 2048 vertices (and vertex normals) per mesh
- 4080 triangles per mesh
- 1 animation sequence
- 512 keyframes per sequence
- 128 bones
Additionally, the following limits apply to the whole MDL:
- 4 bone attachments
- 8 bone controllers
- 32 meshes across all submodels
- 256 animation sequences.
Textures must:
- Be 8-bit uncompressed BMP files.
- Have a resolution which is a multiple of 8 (multiples of 16 are preferred).
- Have a resolution which does not exceed 512x512 (soft limit; raised to 1024x1024 in
Sven Co-op and other engines like
FTE).
- Have a file name which is not longer than 64 characters (including the .bmp extension).
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While the HLMDL format can handle over 100K tris, the old OpenGL renderer struggles with such "high-poly" models, even on high-end GPUs.[1]
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This is obviously not a problem for games on engines much newer than
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Flags
Model flags
Particle effects cannot be combined, but all others can.[Clarify]
Bit | Flag name | Particle effect? | Description |
---|---|---|---|
1 | EF_ROCKET | Yes | ![]() |
2 | EF_GRENADE | Yes | ![]() |
4 | EF_GIB | Yes | ![]() |
8 | EF_ROTATE | No | Rotate this model around its origin, like the weapon pickups in ![]() |
16 | EF_TRACER | Yes | ![]() |
32 | EF_ZOMGIB | Yes | ![]() |
64 | EF_TRACER2 | Yes | ![]() |
128 | EF_TRACER3 | Yes | Like EF_GRENADE, but only has one trail |
256 | EF_NOSHADELIGHT | No | Reduces intensity of shadows on the model, without making the model flat ![]() |
512 | EF_HITBOXCOLLISIONS | No | Use hitbox for collision instead of bounding box |
1024 | EF_FORCESKYLIGHT | No | Always use skybox lighting, regardless of model location |
Texture flags
Bit | Flag name | Description |
---|---|---|
1 | STUDIO_NF_FLATSHADE | Shade the model a single tint, without any shadowing, resulting in the model looking "flat" like a cartoon character. |
2 | STUDIO_NF_CHROME | Use matcap environment mapping to render the texture as a sphere map.
![]() ![]() ![]() ![]() ![]() |
4 | STUDIO_NF_FULLBRIGHT | Display texture at maximum brightness, ignoring lighting.
![]() ![]() ![]() |
8 | STUDIO_NF_MIPMAPS | Generates mipmaps for the texture, greatly reducing texture aliasing at a distance. No effect in ![]() ![]() ![]() ![]() |
16 | STUDIO_NF_ALPHA | Unused? |
32 | STUDIO_NF_ADDITIVE | Use additive translucency. Still affected by entity lighting; use the Additive rendermode on an entity to ignore lighting.
![]() ![]() ![]() ![]() |
64 | STUDIO_NF_MASKED | Use binary alphatest transparency, wherein the last palette entry of the texture is transparent. |
In other engines
Half-Life MDLs are supported by FTE and the
Unity game
Codename: Loop.
External links
References
- From the GoldSrc Model Export Tutorial by The303:
In order to compile models with more than 4080 triangles, you must break up your SMD's into parts and give them their own $body lines for compiling. Also, FOR THE LOVE OF ALL THAT IS HOLY PLEASE DO NOT GO CRAZY ON YOUR TRIANGLE COUNT; remember this is goldsrc, not source engine. Going any higher than 9000 tris is excessive and direct ports from source/other games are inefficent, wasteful, and cause performance issues for the old renderer.— The303