Spiral Stair Tool Icon_PrimitiveShapes_SpiralStair

Creates a Spiral Stair.


  1. Select Spiral Stair Tool

  2. Drag the mouse on a floor or an another polygon as if you make a cylinder.

  3. Release LMB and move the mouse cursor in a normal direction to raise the height. You can change the direction of the stair by pressing SPACE.

  4. Click LMB to stop raising.

  5. Type the properties in inspector to adjust the shape of the stair.

  6. Press SPACE to complete or Press ESC to cancel.


LMB Drag

Starts to create a spiral stair.


Change the direction of the stair or Completes creating a spiral stair


Cancels creating a spiral stair.


Select Only Visible

If on, the shape can be built on only a visible polygon. Namely backfaced or occluded polygons are excluded.

Floor Height

The height of the floor where the primitive shape is built by LMB Dragging.


The step width.


The height of the stair


The inner radius of the stair. The whole radius of the stair from the center will be Radius + Width.


How curved the stair is.


Reflects the stair.


The spiral stair with this property enabled will be glued to the polygon where it started to be created. It means that the hidden part of the floor polygon by the created stair is removed.

Angle Snap

When you drag the mouse with this property on, the direction of the spiral stair will snap to every 90 degree.


Spiral Stair created on the floor. Its curvature is 270 degrees.


Reduces Width property and Increases Radius. Its curvature is 180 degrees.