Improve GridMap and 3D level design workflow

[Nodragem]

Describe the project you are working on

I have been working on a Top-down Action/Adventure starter kit. It inspired all the ideas I've got to improve the level design workflow in Godot. It is open source and available here: https://github.com/Nodragem/top-down-action-adventure-starter-kit

Describe the problem or limitation you are having in your project

There are many little things that can be done to make the on-grid level design experience (e.g. gridmap) greater and I will be listing them here, as a working plan for future contributions.

I am very happy to get feedback and help in shaping this plan for better on-grid level design tools and implementing it!

Describe the feature / enhancement and how it helps to overcome the problem or limitation

Outside Gridmap

• change default drag-and-drop behaviour of 3D asset to add as sibling Make "add as sibling" the default when drag-and-dropping an asset into 3D View #9682
• preview/thumbnail of packedscene containing a node3d/mesh
• absolute snapping
• snapping relative to a Gridmap
• hide big gizmo in selection mode (to easily select small objects in levels)
• easier to understand grid properties in Editor Setting (e.g. Grid Division Level Max?)

Gridmap Small Improvements (but impactful)

• fixing moving/duplicating a set of tiles in Gridmap
  Change default parenting behavior when drag-and-dropping to 2d and 3d editor godot#91874
• (to be reviewed) moving the gridmap to its own bottom panel
  • surface tools and actions in the UI
  • fix rotation of the selection area after pasting
  • better integration with 3d editor (transform mode to rotate, move, scale gridmap)
  • allow keeping focus on Gridmap even when click else where (not in transform mode)
• change paste selects to a better name
• fix: selection rotation when working centerX, centerY, centerZ are True
• fix: gridmap does not update when used as a scene in a scene
• allow to rotate selected cells
• add flip/mirror horizontal/vertical Add flip/mirror option to GridMap #5883
• show mesh origins (Add a toggleable mesh origin display in the GridMap editor #6651)
• show colliders
• painting/selection tools: paint on top of used cells (useful for adding a block on top of a block)

Mesh Library and Gridmap Palette

• add "delete from mesh library" in the palette
• multi selection in palette (which will allow for random paint/fill)
• add tags or categories with tabs
• possiblity to work with multiple mesh libraries?

Brush improvements

• improve brush/eraser preview: hide current tiles under the preview: GridMap: hide tiles when mouse hovering over them (to give ability to see how gridmap will look like after placing new tile) godot#5526
• add brush spacing. Modular assets often come in 2x2 size to work on a 1x1 grid, hence to control spacing is important. More details here: Add a Brush Spacing property to GridMap to control spacing between tiles when using paint/fill tools #9612
• add brush size and shape. Possibly add a preset to save different shape/size.
• add tile blocks (or group of tiles): save selection of tiles on the gridmap as a tile block. This tile block is selectable in the palette as a tile. For instance, we select a corner made of a floor tile and 2 walls and we save it as a tile block. We can now select it in the palette and paint it as a normal tile.
• add random tile fill/paint: allow multiple tiles to be selected in the palette, and allow to set probability by tile (similar to what we have in Tilemap, except that we can set the probability ourselves).
• add random tile preset: possibly to save a selection of tiles and probabilities as a preset.

Gridmap Bigger Improvements:

• improve selection tool:
  • allow complex selections. At the moment we can only select cubes!
  • allow to add, remove from selection
• improve paint/selection tool:
  • allow Point, Line, Rectangle, Cube selection
  • select on xy, yz, xz plane
  • while having nice keyboard shorcut which do not conflict!
• clever fill tool: like terrain but needs to work with 3D modular assets rather than 2D tiles worflow.
• merge two gridmaps
• copy-paste between gridmaps

Navigation Mesh:

• discuss the possibly to sunset the current navigation system by tiles? and replace it by navigation region.

Describe how your proposal will work, with code, pseudo-code, mock-ups, and/or diagrams

This proposal will be divided into smaller proposal and PR. It is here to give a big picture.

If this enhancement will not be used often, can it be worked around with a few lines of script?

No.

Is there a reason why this should be core and not an add-on in the asset library?

Gridmap is already core.

[Hiiamwilliam]

I'd like to share my thoughts. I've spent a good time working on a 3.X plugin (not published yet) to fix some issues and add some functionalities. However, I did some quick tests, and will consider the 4.4.dev3 version as reference for this comment.

Before thinking about future improvements, I'd prefer if some current limitations/bugs were taken care of - I'll list them with a bunch of other unorganized thoughts at the end. Meanwhile:

absolute snapping + snapping relative to a Gridmap

Snapping what to what? Nodes to the GridMap's cells?

easier to understand grid properties in Editor Setting

Seems unrelated to GridMap, how would this help?

fixing moving/duplicating a set of tiles in Gridmap

I think you linked the wrong url.

fix: selection rotation when working centerX, centerY, centerZ are True

This seems to happen only if Paste Selects is True.

allow to rotate selected cells

Do you mean "rotate Selected cells around themselves, without rotating the Selection"?

add flip/mirror horizontal/vertical

I think it would be better to add the ability to create and add flipped versions into the current MeshLibrary. The linked pull request suggests changing the cell's ...constructor(?). However, this would affect all cells, and not all cells need to be flipped. Performance impacts must be measured.

show colliders

Seems useful, but at the same time, not really? When is this information important within GridMap? Not all items have collision.

paint on top of used cells

I thought about this in my plugin. How would you do this? Check which cell is under the cursor, then paint on the cell's coordinate + Vector3.UP? What if there's a different cell on top of the cursor? What about painting a cell below or at the sides?

add tile blocks (or group of tiles)

Seems like a good idea. But I wonder, if you end up using a few cells to build several groups, workflow may not improve that much: you'll still need to select from several choices then paint blocks individually. Also, you may have to constantly switch between two different menus to pick what you want.

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Thoughts about improvements:

• Reminder: currently GridMap has no dedicated contributor. This likely means that only trivial changes will end up being merged in a timely manner - bigger changes may be pushed to the future to not break compatibility. It is what it is.
  So, if you feel like making pull requests, set your expectations accordingly.
• MeshLibrary limitations:
  • This one liner should be removed: the GridMap menu's ItemList sorting.
    There is no reason for it to be like this. It changes the order of the MeshLibrary Items depending on their names, ignoring ID order. This can make different MeshLibraries be displayed in the same way, which is wrong. In the past (and present Godot 3.X), this causes a difference between which cell is selected in the ItemList and which cell is displayed by the cursor.
  • Make the menu remember what was the last selected item from the current GridMap. Not only it's an easy Quality of Life update, but it would fix an error that still occurs when you select a GridMap that has less items than the current one. This could be as simple as a MeshLibrary meta data entry.
  • MeshLibraries should have a better way to add and remove items.
  • Match how many bits MeshLibrary and GridMap accept.
  • When using the built-in functionality to generate MeshLibrary from a Scene:
    • Warn (somehow, somewhere) that Resources should be external.
    • Make it more flexible: #3821, #3406.
• GridMap limitations:

  • Make changing floors accept echo Input events. Currently, if you press and hold Q or E, it will apply only one floor change.
    Alternatively, add a functionality that centers all three plane levels to the cursor for quick changes.

  • improve paint/selection tool: select on xy, yz, xz plane

    Something changed between Godot 3 and 4. In 3, you can modify the extents of the Selection after creating it using Shift + Q/E. You can change the currently edited Plane and make the Selection grow/shrink in different directions. It's kinda weird, but it's something. If this is what you meant, then it's a matter of restoring/updating old behavior.

  • By far, the smallest change with biggest impact that GridMap can have is a signal or callback to get last edited cells.
    You mentioned several ideas that could be done via user-provided script if this information was available: paint on top of used cells, add tile blocks, add random tile fill/paint, clever fill tool, work with multiple MeshLibraries (by using a GridMap "manager" that signals to other GridMaps which cells should be modified), and possibly act as brush size and shape.
    It would also help with auto-tiling. Even this plugin mentions that the lack of information about last edited cells is a limitation. Note: that plugin doesn't work with Selections - so even plugins have trouble.

• Other changes:
  • Either make GridMap use the name of items instead of ID or provide a proper way to handle MeshLibrary refactoring.
  • About "show mesh origins": I can imagine it leading to either visual pollution if the proposed radius is too large or unhelpful pointers if it's too small. Also, I assume most items fit in one cell - you would add a whole new visualization mode just to check for a few big items.
    I think proper solutions to this require knowing the "actual occupied volume" of an item. I imagine this could be done if there were Collision Mask + Layer per MeshLibrary item instead of per GridMap AND the GridMap Editor could check for overlap before Painting/Erasing. Then, Erasing any cell of the bigger items would correctly erase them.
    Now, this wouldn't fix trying to erase a cell whose mesh has gaps by clicking on the coordinates of the gap... You would have to somehow define which neighboring coordinates around the origin are part of this cell, then make the Editor understand that.
  • About brush spacing: seems good but it's dependent on GridMap's cell Size and/or Scale. They can be changed in such a way that even if the spacing is respected, the meshes would still overlap. A more robust solution is to combine the mesh's AABB + cursor rotation to check for overlap. Works fine for Fill Selection, but has problems when Painting in self-intersecting manner.
  • A handy information that could also be made available along last edited cells is coordinates in the Selection. You could for instance write a plugin with custom actions to "Paint cells A and B with random rotation", or "replace items A with B" etc.

[Nodragem]

Thank you for this fantastic feedback!

I will try to digest your suggestions and edit my list of improvements accordingly later this week.

For some of my ideas, like "adding tile blocks" I will be making related proposals with pictures, so that it is easier to understand them.

Yes I intend to make PRs ! I am rather optimistic that a lot of trivial or uncontroversial changes can be made in combination to make the user experience better. Let's see how it goes.