radicalcsg / chisel.prototype

Work in progress prototype for the Chisel Level Editor, for Unity

Chisel.Prototype

Chisel is an extension for Unity that allows for rapid, iterative, non destructive level editing!

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• Click here for information on how to get started
• Want to help out? We have some good first issues here
• If you have questions be sure to ask in the discord! Click here for to join the official Discord server!

Notes:

• Chisel requires Unity 2022.1.0b5 or newer
• UX is still under development
• CSG algorithm is still under development
• It is not yet ready for production, but please feel free to try it out, or better yet, help out!

Features (incomplete)

• Constructive Solid Geometry Algorithm that generates geometry in real-time
• Add and remove geometry to your level using CSG allows for fluid, interactive, non destructive workflows
• Higher level "generators" that create more complicated geometry to perform CSG with, while retaining context of what it is you're creating (if you create stairs, these will remain stairs that you can edit and tweak)
• Hierarchical Constructive Solid Geometry, allows for generators and brushes to be act as if they're one whole (composite), to perform CSG on other objects with
• Works well with prefabs, drag and drop windows onto walls including their holes
• Draw 2D shapes (possible to turn straight lines into curves) on existing CSG surfaces and extrude them
• Precise snapping to surfaces, edges, vertices and grid lines
• Rotatable & movable grid

Planned Features (incomplete, and in random order):

• Debug Visualizations to see shadow only surfaces, collider surfaces etc. (partially implemented)
• Double sided surfaces
• Extrusion from existing surface
• Subtractive Workflow
• Clip Tool
• Normal smoothing
• Node Based Generators for easy procedural content generation
• 2D shape editor
• Hotspot mapping
• Sub-Models
• Trim Decals
• Grid Objects

Packages overview:

• com.chisel.core Low-level API and functionality (based on DOTS technology)
• com.chisel.editor Unity Scene Editor functionality and API, tools and UI
• com.chisel.components Unity Monobehaviour runtime API (to allow for possible ECS replacement in future)
• com.scene.handles.extensions Custom scene handle extensions

Extensions:

• Source Engine 2006 Map Importer for Chisel Editor
  • Decal support for importer
• Quake1 Importer

Known issues:

• There are some cases where triangulation fails
• There are some cases where overlapping surfaces create overlapping polygons

If you find any failure cases, if possible please provide us with a reproducible scene so we can more easily fix it!

The core technology is based on the algorithm explained in this GDC 2020 talk

chisel.prototype's Issues

Editing pivot offsets actual brush

Editing the pivot of any brush in the X or Z axis causes the entire brush to move instead of just the pivot.

The linear stairs tool should have an easy way to change direction

When you create the linear stairs it might be orientated in another direction than you intended.
It should be easy to change the direction of the steps by 90 degrees, without changing the shape of the box.

Drawing shapes on brushes isn't consistent

When drawing brushes (of all types it appears) will occasionally not register legal draw surfaces.

Example:

Create placement tool for the Stadium component

Hemisphere/Sphere generators need to be able to be generated with uniform sizes

right now when creating spheres/hemispheres we don't scale them uniformly, and this is probably a desired option

Improve handle movement

Currently when dragging a handle over a plane the movement doesn't follow the mouse properly, this should be improved. Keep in mind that in some situations it's not desired to actually follow the mouse properly. For instance when a plane creates a horizon in the distance and the mouse crosses the horizon, this would create an infinite movement if it was "precisely following the mouse".

When negating the z-size of the linear stairs it should change direction

Vertex coloring

The ability to paint colors, or other custom data, on brush vertices would be very useful

Selection doesn't properly select the front most surface

When moving the mouse over a surface, it'll go back and forth between different surfaces

Some Generators need their own visualization when placing them

At the moment some generators show outlines for cylinders or boxes when they should have their own visualizations. This needs to be implemented

Warnings about using deprecated Prefab API

Packages\com.chisel.components\Chisel\Components\API.private\CSGNodeHierarchyManager.cs(865,11): warning CS0618: 'PrefabUtility.GetPrefabType(Object)' is obsolete: 'Use GetPrefabAssetType and GetPrefabInstanceStatus to get the full picture about Prefab types.'

Packages\com.chisel.components\Chisel\Components\API.private\CSGNodeHierarchyManager.cs(865,65): warning CS0618: 'PrefabType' is obsolete: 'PrefabType no longer tells everything about Prefab instance.'

Packages\com.chisel.editor\Chisel\Editor\Components\Containers\Model\Editor\CSGModelEditor.cs(267,16): warning CS0618: 'PrefabUtility.GetPrefabType(Object)' is obsolete: 'Use GetPrefabAssetType and GetPrefabInstanceStatus to get the full picture about Prefab types.'

Packages\com.chisel.editor\Chisel\Editor\Components\Containers\Model\Editor\CSGModelEditor.cs(268,21): warning CS0618: 'PrefabType' is obsolete: 'PrefabType no longer tells everything about Prefab instance.'

Packages\com.chisel.editor\Chisel\Editor\Components\Containers\Model\Editor\CSGModelEditor.cs(268,50): warning CS0618: 'PrefabType' is obsolete: 'PrefabType no longer tells everything about Prefab instance.'

Brush 'layers' or contents

In practice it's very useful to be able to place brushes in a level that only add to the MeshCollider, or the reverse: only add to the visible mesh, but not to the collider.
It's also useful to be able to add brushes for things like water, where you do not want to remove the parts of other brushes that are inside of it, but you do want to do the reverse..
Furthermore, sometimes, for efficiency reasons, you want some brushes to not perform CSG with other brushes at all.
If we have a system where there are certain user definable 'layers' (but with a different name) and be able to define how they interact with each other, then we could give users some sensible defaults and let them set up additional use cases if they need to.

Box tool does not align correctly with drawing plane

Create placement tool for the Torus component

Distance Measure Tool

An easy to use distance measurement tool would be great. Something like in unreal engine would be perfect. Just a line + measurement above it when you click between the two points being measured.

Selection doesn't work correctly when more than 1 model is in the scene

Generators should have a version number

Since generators create all their brushes from scratch, any change in behaviour could potentially drastically change how a level created using generators would look.
So we cannot simply change a generator once people have already started using it, but we might end up in situations where we feel we really do need to improve a generator.
By adding version numbers we can make it possible to handle scenarios like upgrading/converting generators, or having different behaviours for different versions of generators. This gives us more control in situations like this.

PreviewRendererUtility error spams console when a brush is selected

A PreviewRenderUtility was not clean up properly before assembly reloading which lead to leaking this scene in the Editor. This can be caused by not calling Cleanup() during the OnDisable of an Editor or an EditorWindow.
UnityEditor.PreviewRenderUtility:Finalize()

Editing duplicate of brush edits original as well

Duplicating any brush (CTRL + D) and editing the duplicate's size causes changes to the original brush to copy these changes in the visual mesh only.

Vertex color volume decals

a subdivided volume with colors defined at it's points, which can be moved around in the scene
where brush vertices end up in the volume, the colors will be interpolated and applied to the vertex

Need way to expose additional options for generator placement to user

All the generator placement tools have multiple options, but these are not exposed to the user in the user interface. This needs to be improved.
These options should also be persistent, so that the user can set their prefered settings and keep using those.

New managed CSG algorithm

New managed CSG algorithm needs to be written and replace the native implementation

Clip Tool

A relatively standard tool in CSG editors, a clip tool where you can quickly create a plane and split/clip brushes.

Ability to edit generic brushes

Right now generic brushes do not have an editor that allows you to move it's vertices, clip it, or split edges. etc. This should be created

Ability to create instance of existing generator

A different, explicit operation should exist for creating an instance (which can be tackled as a new tool possibly? needs UX design)

Need to be able to move vertices in the generic brush editor

The generic brush editor does nothing at the moment. At a bare minimum we need the ability to move vertices

Repeat previous generator at clicked position with shift + click

Capsule component needs ability to modify height of top and bottom caps

The generator supports it, but it's not exposed in the editor

Extrusion from existing brush face

It would be beneficial to have an extrusion function similar to RealtimeCSG.

When canceling creating a shape with escape, a newly created model is not removed

When you create a shape in an empty scene, it'll automatically create a model for you.
When you cancel the shape creation by pressing escape, however, this model is not removed

Isolate/Hide brushes

Ability to hide or isolate specific brushes, very useful when working on complex scenes.

Unity 2019 has visibility controls which would be best to use, but a solution would need to be made for 2018 if we support that too.

Can't use the Axis Gizmo when using a Generator

If you have any of the generators selected, clicking the unity axis gizmo (to switch perspective mode or move the view), it passes through and just draws the generator.

World units for snapping distance

For ease of reference, an option to show customisable distance units wherever distances are shown (space permitting).

• Add setting to toggle showing world units (default on?)
• Add setting to define the units show (default m for meters)
• Show units on bottom toolbar for snapping distance

Material modifying brushes

We should have special brushes that cut the brushes that it intersects, but doesn't add or remove any geometry itself. But it does modify the materials of the brushes it intersects with.

Freedraw should support self-intersecting shapes

It would be nice from a workflow perspective to support self intersecting shapes when in freedraw mode.
For example, making an hourglass shape with 4 vertices, where 2 edges intersect. Right now this is an invalid shape, but if the polygon decomposition code could handle self intersections, there essentially wouldn't be any 2D shape that would fail. (except for straight lines)

Finish the pathed/linear/spiral stairs generators

The pathed stairs doesn't always properly generate brushes, and this needs to be fixed.
All the stairs generator don't have all the features that the other stairs generators have and it would be nice to share more code and clean things up.
The pathed stairs should also have an option to fill it's interior

Cylinder resizing only shrinks

Spiral stairs should always point upwards

Placement should always make the sprial stairs point upwards

Surface Editor

Surface Editor Tool

• Modify texture offset, rotation and scale
• Apply materials quickly and easily
• Copy material and surface properties from one face to another
• Automatically UV of entire brush or selected faces based on worldspace coordinates and given scale
• Select default material for new brushes
• "Follow Face" (Match UV offset for multiple faces by dragging over them)

Texture offset changes should be aligned to grid unless the Shift modifier is held. Rotation and scale should work the same too.

Offset/Rotate/Scale should honor the relevant selected tool in Unity

A list of recent/frequently used materials for easy selection, plus user-definable groups of materials to select from, with customizable previews (show Sphere, Plane, Cube preview etc, resize previews as in the unity Project window)

Ability to snap UVs to edges of the face and edges of the texture, and shear textures.

Some mockups should be created to plan the UI and features out and get a feel for what considerations may arise.

Newly created generators/brushes should re-use existing models

Right now generators tend to create new models even when it's not necessary.
This is undesirable and should be fixed.

Cylinder tool preview does not match generated radius

Need to have a proper hashing solution

Need to have a proper hashing solution, written in C#, to quickly hash arrays of Vector3/Vector4/floats/ints to easily determine if meshes are identical.

Without Object mode selected, the translate/scale tools don't work on non-chisel objects

If you select any tool other than Object tool, the gizmos for translating, scaling etc do not appear when selecting any non-CSG object, which is confusing can easily break flow.

The toolbox shouldn't affect how you handle anything outside of Chisel, or at the very least it should default back to Object mode when you select anything else.

Surface colors

The ability to set a color to an entire surface of a brush

Create placement tool for the Pathed stairs component

More snapping options for generators

When changing the shape of a generator, we need to be able to snap against more things than just the grid.
This means we need to add support for handles to snap against a variety of things.
For example, snap against vertex, position where grid intersects an edge/surface, uv-space snapping of vertices to perfectly align a vertex with a texture etc. etc.

Ray-casting into scene needs to be rewritten

Ray casting into the scene is very flaky and unreliable.
Proper tests need to be written and then the ray casting code needs to be rewritten

Bevel/Chamfer tool

Able to bevel/chamfer edges, with optional subdivisions to create smoothed edges.

Subtractive Workflow

Users should easily be able to work in a subtractive workflow, so the void is solid by default rather than empty.

I believe this was discussed to be implemented as a single infinite additive brush at the top of the hierarchy, but we should also consider how it should work on the UX end.

It could be a visible toggle (for instance in the tool bar) called "Fill Void" or similar. This could toggle the infinite brush you start with. Any thoughts?

Create placement tool for the Revolved component