Fixture Mods

Fast Rundown

• Fixtures are a Blueprint class, A_Fixture is the base class.
• Fixtures are comprised of up to 4 Sub-meshes (UVMesh, Conforming Mesh, Skinned Mesh, and Additional Mesh).
• All or none of these are required:

• UV Mesh (the silhoutte of the cut out)

• Conforming mesh (e.g. Grilles, or the front headlight glass)

• Addditional Mesh (Things like Wing Mirrors)

• Skinned Mesh (Headlight Internals)

• A Fixture Category
• Snap to Centre Strength
• Lock to Cardinal (should it always face forwards, backwards, etc. Rather than face in the direction of the car body normal.)
• Needs Material Slots setup correctly
• Needs Preview Thumbnails

The Fixture Blueprint and its Components

A Fixture is composed of a Blueprint that contains the fixture settings and sub-meshes.

Fixture Settings

Fixture settings are grouped in to two categories: Editable, and Fixture.

• Editable settings are for the properties of the fixture that gets placed to the car.
• Fixture settings are for where the fixture is located in the Automation UI.

Editable settings

• Centre Snap Distance - Defines at what distance the fixture will snap to the centre line of the car (default 10cm)
• Conforming Mesh - Defines the Static Mesh sub-mesh used by this fixture
• UVMesh - Defines the UVMesh sub-mesh used by this fixture
• Skinned Mesh - Defines the Skinned Mesh sub-mesh used by this fixture
• Additional Mesh - Defines the Additional Mesh sub-mesh used by this fixture
• Lock Normal to Cardinal' - When the fixture is set to 'Lock to Cardinal': all the verticies of the Conforming Mesh, all the bones of the Skinned Mesh , and the Additional Mesh, will conform backwards in to the car at the closest 90° angle. When the fixture is not set to 'Lock to Cardinal: all the verticies of the Conforming Mesh, all the bones of the Skinned Mesh, and the Additional Mesh, will conform inwards from the center of the fixture.

Fixture settings

• Fixture GUID - Unique identifier for this fixture.
• Family GUID - Identifier for this fixture family. Should be unique to every other family GUID, and identical to every other variant of this fixture
• Fixture Type - What category this fixture should be in (ie: headlight, aerial, grille, etc...)
• M Ghost Material - Defines the material to use when the fixture cannot be placed where the player is attempting to place it. This setting shouldn't change from its default 'FixtureError' material unless you really want to change it.

Fixture Sub-Meshes

UVMesh

The UV Mesh (imported as a Static Mesh in UE4) is a flat silhouette that tells the fixture to cut a hole in to the car mesh. You will only need vertices along the outside edges of the UV Mesh. An UV Mesh is only required if your fixture intends to cut in to the car.

Conforming Mesh

The Conforming Mesh (imported as a Static Mesh in UE4) is a mesh where each vertex is deformed to match the car mesh. It is also a required mesh if the fixture has an UV Mesh, as the Conforming Mesh is used to cover over the hole created by the UV Mesh.

Skinned Mesh

The Skinned Mesh (imported as a Skeletal Mesh in UE4) is used when you have parts of a fixture that should conform to the rough shape of the car, but also retain the dimensions and ratios of its components. A Skinned Mesh will have a bone for each element that should remain the same shape, and should be parented to the bone root. The bone location should be on Y-0 (not inside the fixture, or floating outside the front of the fixture) to allow for the proper rotation of its weighted components. All verticies of the Skinned Mesh that are further out of the car than 0.1cm will conform to the car as if they were part of a Conforming Mesh. Because of this, there will be a small gap of at least 0.1cm between the edge of the Skinned Mesh and the car body. To cover up this gap, use a Conforming Mesh to link the edge of the Skinned Mesh and the car body.

Additional Mesh

The Additional Mesh (imported as a Static Mesh in UE4) does not deform in any way and will remain in place relative to the location of the fixture. An Additional Mesh has no skin or bones, and no part of it will deform to the shape of the car. An example of an Additional Mesh is an exhaust, or the mirror section of a wing mirror.