Model states

An object can change while the game runs. A lamp goes on and off. You do not make a model for each state. You make one model, and you name the parts that change. Viewpoint shows the parts for the state of the object. When the state changes, Viewpoint changes the parts at once. It does not load a second model.

A version 2 manifest also has group binds: one line for all the facings of an object.

To change a version 1 pack, see Migrate to version 2.

Parts

Your OBJ file has objects (o) or groups (g). Put a tag in the name of an object or a group:

Tag in the name	The part shows
[lit]	Only when the object is lit.
[!lit]	Only when the object is not lit.
No tag	Always.

lamp.obj

mtllib lamp.mtl
o Base
usemtl wood
f ...
o Shade[!lit]
usemtl shade
f ...
o Shade[lit]
usemtl shade_on
f ...

• To change the look of a part, put the part two times in the model: one time with [!lit] and one time with [lit]. The two copies can have a different shape, or different UVs on your texture.
• Make only the parts that change. The other parts are shared by all the states.
• The tag can be anywhere in the name. Shade[lit]_Mesh.001 is correct.
• The tag of a group (g) is more important than the tag of its object (o).
• A name with both tags shows in all the states, as a name with no tag.

Glow

A material glows when your MTL gives it an emission colour that is not black (Ke), or an emission map (map_Ke). A part that glows is drawn as bright as its texture, without the light of the scene: a bulb, a screen, a flame.

lamp.mtl

newmtl shade
map_Kd lamp.png

newmtl shade_on
Ke 1.0 0.85 0.6
map_Kd lamp.png

Blender writes Ke when the material has an emission colour. Use a glowing material only on a [lit] part, or the part glows in all the states.

Note

Each material uses the texture of its own map_Kd. The two copies of a part can use different materials, with different textures. A model that uses one texture for all its states uses less memory. See Format.

Lit

An object is lit when:

Object	Lit when
A lamp or a light switch	It is on and it has power: a battery, electricity on its square, or the power grid. A street lamp is lit only at night.
A stove, an oven or a microwave	It is on.
A generator	It is on.
A radio or a television	It is on.
A fireplace or a barbecue	It burns.

Any other object is never lit, and its [lit] parts never show. When an object changes, Viewpoint shows the other parts in a short time (about a tenth of a second).

Group binds

A group bind gives the same model to all the facings of an object:

models/manifest.txt

format=2
model.chair=chair.obj
group.furniture_seating_indoor_02/Wooden Chair=chair,0,0,0.1,0,1

Line	Meaning
group.<tileset>/<name>=<model>,<degrees>,<x>,<y>,<z>,<scale>	The model of each facing of the object. <tileset> is the sheet of the sprites, for example furniture_seating_indoor_02. <name> is the name of the object: its GroupName, a space, and its CustomName, for example Wooden Chair. If the object has no GroupName, use its CustomName. The values are the same as in a bind.

You make the model for the object that faces south. Viewpoint turns the model to the Facing of each sprite: south 0 degrees, west 90, north 180, east 270. It turns the offset <x>,<y> together with the model. Thus a model that you move back against the wall of a south-facing chair stays against the wall when the chair faces east.

• A bind of a sprite (bind.<sprite>=) is stronger than the bind of its group, in the same pack.
• An object that has more than one square (its sprites have a SpriteGridPos) does not get a group bind. Bind each of its sprites.
• If a group finds no sprite, the log names the group.
• Without format=2, Viewpoint ignores group lines, and the log names them.

Other states

Open, closed, damaged and facing are not states of a model. In the game, each of them is a different sprite: an open door, a smashed window, each facing of a chair. Bind that sprite. A bind cannot have a state in its key: Viewpoint ignores bind.<sprite>[lit]= and names the line in the log.

Rules

• See Format for how a model stands on its square.
• Models count in memory.packMiB. Viewpoint loads a model the first time that the game shows it.
• The package nearer the top of the Active column wins a sprite. See Order.
• A line that Viewpoint cannot read is ignored. The log names its line number.

Note

A model with parts works in an older Viewpoint too: there, all its parts show at the same time. A version 2 manifest needs a Viewpoint that supports it. An older Viewpoint ignores its group lines.

For a model that needs code, see Model providers.