Edit collision

Collision is the invisible geometry that blocks movement, takes weapon hits and detects players. Studio shows it as a layer, exports it as glTF or OBJ, and imports your edits. You can move collision instances, move and resize parts inside a shape, change shapes and add new shapes. You cannot remove collision.

Collision edits are unverified in game.

Show collision

1. Open a map, a mission or an asset.
2. Open Layers.
3. In the Collision row, tick Box to see each shape’s box, or Content to see its triangles.

The first time, Studio loads the collision in the background. The view stays usable.

The colors show the role and the shape:

The Layers menu counts the placed, distinct and drawn shapes. Collision follows the bubble, tree, map and mission filters.

Inspect collision

1. Tick Content in the Collision row.
2. Hover a triangle to see its role, shape kind, triangle count, compound and instance. A hitbox names its damage region, such as Hitbox head.
3. Click a triangle to select its placement.

When an object and a collision triangle are both under the pointer, the nearer one is selected. With Content off, a click selects objects only.

The Inspector shows the shape kind, role, initial state, region hash, bone, triangle count, parts, shape, compound, instance, source, object list row, local transform and world position. For static collision, Static instance lists the render rows at the same transform. Select next to a row selects that object. The Collision and Asset buttons switch the Inspector between the collision and the asset.

The Report tab’s Collision section lists the counts, the load time, content with no triangles, and whether the last change updated in place or reloaded.

Edit parts of a shape

One baked collision mesh can hold the collision of many objects, such as the leaf hulls of a tree in a map mesh. A part is one connected piece of a shape. You can move, rotate and scale parts inside the mesh without Blender.

1. Open a project and the map.
2. Tick Content in the Collision row of Layers.
3. Click a collision triangle. The Inspector’s Parts section shows the part under the pointer, and the view outlines it.
4. Press Add picked part.
5. Click another part and press Add picked part again. Repeat for each part.
6. Type Move, Rotate (deg), Scale and Pivot.
7. Press Apply to parts.

Rotate is in degrees around X, Y and Z. Scale is one value for all three axes. The pivot starts in the middle of the chosen parts, so Rotate and Scale keep the parts in place. Pivot at cursor moves it. Pivot at parts center puts it back.

The chosen parts can be in several shapes. A click on another part of a shape with chosen parts keeps them. A click on any other shape starts over. A second click on the picked part clears the selection and all chosen parts. To drop one part, use Remove picked part. Clear parts drops them all.

One Apply is one undo step, however many shapes it changes. After Apply the chosen parts clear and the values reset. When Apply is refused, the parts and the values stay, and the status bar says why.

Only mesh and convex shapes can take a part edit. A body on a bone, or a box, sphere, capsule or cylinder, can be chosen, but Apply to parts stays off and says why. Every placement of a changed shape changes too. The Inspector counts them.

Select connected parts

Select connected chooses every part that touches the picked part, or comes nearer than Gap.

1. Click a collision triangle.
2. Choose a scope in the list above Select connected.
3. Type a Gap in meters. The default is 0.02.
4. Press Select connected.

The search also grows from the parts you already chose. With no triangle picked, it starts from the whole shape. The Inspector then says how many parts it found and how long it took. The search examines at most 50,000 parts and says when it stops there.

Each physics body, such as one hitbox, is its own shape. So for a body the scope starts at This entity, and Select connected finds the touching bodies of the character. For any other shape it starts at This shape. Studio keeps the scope you pick for each of these two cases.

A map’s static collision is one entity, and most of it touches the ground. So This entity and Touching shapes on a map can choose almost the whole map, and take a few seconds. The view stays usable while it searches. A part inside a hollow mesh, with no contact, is not found.

Add parts to a group

A group keeps a set of chosen parts, so you can choose them again and move them with the group’s objects.

1. Open a project and the map. An asset view cannot add parts to a group.
2. Choose the parts, as above.
3. Open Add to group under the chosen parts.
4. Choose a group, or New group.

A group holds up to 50,000 collision parts. The parts follow the group when you move, rotate or scale it. Move, rotate and scale objects explains groups.

Collision in an asset view

Opening a Havok packfile or a collision owner shows its collision at once. An entity shows its physics bodies on its bones. While its animation plays, the bodies follow the pose. A static model shows the collision of the first placed row that uses it.

Export collision

1. Open the map or the asset.
2. Choose Assets > Export collision….
3. Pick a file type and a name.

Edit the export in Blender

1. In Blender, import the GLB or glTF.
2. Make your changes. The table below lists what you can do.
3. Export glTF with Custom Properties included. Without them, the nodes lose their identity.

A copy whose mesh you then change becomes a new shape. Do not delete objects: removing collision cannot be imported.

Import the edits

1. Open a project.
2. Open the same map or asset.
3. Choose Assets > Import collision….
4. Pick the edited GLB or glTF.

The import is one undo step. Undo also removes new shapes. The shown collision updates in place when only instances or per-mesh shapes changed.

An export older than the project’s collision is refused. Export again and redo the edit.

Choose the kind, compound and material of a new shape

A new mesh object reads three optional custom properties.

A new shape also copies the collision filter of the nearest existing face. You cannot choose the filter.

Edit collision in a bundle

A full asset bundle holds the asset’s collision in a child collection named Collision. See Edit an asset in Blender.

• Each placed shape is one wire object, left out of renders.
• Placements of one shape share one mesh.
• Each object carries its identity as custom properties, such as sunrise_collision_compound, sunrise_collision_instance and sunrise_collision_shape. Keep them.
• An object whose sunrise_collision_editable is 0 has no stored transform. It cannot move or be copied.
• The collection lists each compound’s material tags in sunrise_collision_materials. The Sunrise sidebar shows them for a selected new object.

The editing rules are the same as above. Import the bundle with Assets > Import Blender asset….

Moving an object moves its collision

When you move, rotate or scale a static object, Studio moves its static collision with it. You do not need to edit the collision separately. See Move, rotate and scale objects.

Limits

Studio refuses:

• Removing a collision instance or object.
• A scale that is not equal on all three axes.
• Different single-user edits of placements that share one native shape.
• A new shape in a compound with no owner, two owners, or inside a shape array.
• A flat convex shape. A convex shape needs 4 hull points.
• A shape edit, by import or by Apply to parts, inside a compound or a shape array. Only a per-mesh packfile takes shape edits.

Static collision internals has the full rules and the format.