Grid-Placer

A Unity3D package to alleviate the pain of creating grid-based maps by hand

Installation

Open the Package Manager Window, click the little + button in the top left corner and choose Git URL. Make sure to copy the URL from the green Code button instead of taking it from the browser URL field.

The Grid Placer Window

In the Toolbar go to Tools > Grid Placer to open the Grid Placer Window. I suggest docking it next to the inspector. Said window contains the following settings:

• Grid
  • Origin defines where the grid's origin lies. Can be used to offset the grid cells or change their height.
  • Rotation defines how the grid is rotated around the origin.
  • Size X defines the grid cell size on the x-axis with respect to the grid rotation.
  • Size Z defines the grid cell size on the z-axis with respect to the grid rotation.
• Height Offset
  • Height defines the currently selected prefab's height offset perpendicular to the grid.
  • Small Step defines the amount the height offset will change when scrolling while holding down Shift in the scene view.
  • Big Step defines the amount the grid height will change when scrolling in the scene view.
• Rotation
  • Rotation defines the currently selected prefab's rotation around it's local y-axis.
  • Randomize defines if the currently selected prefab's rotation around it's local y-axis should be randomized after each placement.
  • Small Step defines the amount the rotation will change when pressing E/Q while holding down Shift in the scene view.
  • Big Step defines the amount the rotation will change when pressing E/Q in the scene view.
• Scale
  • Scale defines the currently selected prefab's uniform scale.
  • Randomize defines if the currently selected prefab's uniform scale should be randomized after each placement.
    • Min Scale defines the minimum random uniform scale.
    • Min Scale defines the maximum random uniform scale.
• Grid Snapping
  • Center makes the currently selected prefab snap to the center of the active grid cell.
  • Edges makes the currently selected prefab snap to one of the four edges of the active grid cell.
  • Corners makes the currently selected prefab snap to one of the four corners of the active grid cell.
  • None disables snapping all together.
  • The Snap Settings are also displayed in the scene view.
• Scene Sampling
  • Sample Height Offset samples the current height offset relative to the grid.
  • Sample Origin Transform sets the grid origin equal to the sample point and aligns the grid rotation to the sampled normal.
    • When in Sample Origin Transform-mode, some additional options are available
    • Sample Position determines if the grid origin position should be sampled.
    • Sample Rotation determines if the grid origin rotation should be sampled.
    • Sample Continuously determines if the the origin should be sampled automatically at every frame.
  • Sample Prefab tries to use the sampled object as a prefab to instantiate. Only works on objects that are already an instance of a prefab (no unpacked prefabs).
• Pool
  • To place prefabs into the scene, they need to be inside the Pool.
  • This can be just one prefab, or as many as you like.
  • When placing the prefabs they will be chosen from the pool randomly. This is very useful for placing different prop variations.
  • To remove a specific prefab from the Pool simply click on it.
  • Clear Pool removes all prefabs from the pool.
• Palette
  • Instance Parent - Assign a scene Transform here to automatically parent all placed prefabs to it.
  • Drag Prefabs here to add them to the active prefab palette.
  • Clear Palette removes all prefabs from the active palette.
  • Palette Display Mode
    • List displays the prefabs in a vertical list format showing their thumbnails and names.
    • Compact displays the prefabs in a grid format showing only their thumbnails.
  • All prefabs in the active palette will be listet below
    • Click the Prefab Thumbnail to add it to the Pool.
    • Prefabs which are in the Pool will marked in green.
    • Click on a green Prefab Thumbnail to remove it from the Pool
    • The X button removes this prefab from the palette.

The Scene Gizmos

In the scene view you will notice the Grid Gizmo which is constantly following your cursor.

• The white lines display the grid's cell which your cursor is currently pointing at as well as indicate it's neighboring cells.
• The green dot displays your cursors position projected onto the grid. With Snapping disabled it's also the position the selected prefab will be placed at.
• The orange dots display the currently available snapping positions according to the active Snap Setting. The selected prefab will be placed at the orange dot which is closest to the green dot.
• The orange lines that appear between the grid lines and the snapping positions are a visual indicator of the height offset when using snapping.
• The green line that appears between the projected cursor position and the prefab are a visual indicator of the height offset when using no snapping.

Shortcuts

Key (In the Scene View)	Action
1	Switch to Center Snap Mode
2	Switch to Edges Snap Mode
3	Switch to Corners Snap Mode
4	Disable Snapping
Scroll	Change Height using Big Step
Scroll+Shift	Change Height using Small Step
E	Rotate the selected prefab clockwise using Big Step
E+Shift	Rotate the selected prefab clockwise using Small Step
Q	Rotate the selected prefab counterclockwise using Big Step
Q+Shift	Rotate the selected prefab counterclockwise using Small Step
R	Cycle through all the prefabs in the Pool
R+Shift	Cycle through all the prefabs in the Pool in reverse
LMB	Place the selected prefab
LMB+Alt	Sample the height of whatever you clicked on (Requires a collider to work)

Prefab Palettes

Prefab Palettes are a custom asset type which can be used to group prefabs. They can then be dragged into the Drag Prefabs here field in the Grid Placer Window to add all prefabs contained in the Prefab Palette to the active palette.

To create a Prefab Palette right click in the Project Browser > Create > GridPlacer > Prefab Palette. You will notice that the UI looks very similar to the Prefab Palette UI in the Grid Placer Window. You can drag prefabs into the Drag Prefabs here field to add them to the Prefab Palette and click on the Prefab thumbnails in the list to remove them.