Mapping Concepts

Note

LMB: left mouse button click, RMB: right mouse button click

Vertices

Vertices are the joins between Lines, and the corners between walls.

  • Press v in the 2D view to enter Vertices edit mode
  • LMB while hovering over a Linedef inserts a single vertex at the cursor position
  • RMB inserts a vertex in line drawing mode: keep adding vertices with RMB until you close the polygon
  • spacebar also inserts a vertex in line drawing mode
../_images/vertices.png

When inserting vertices inside an existing sector, add the vertices in a clockwise direction to create a sector with two-sided Linedefs:

../_images/vertices-sector.png

When adding vertices in an anti-clockwise direction, the sector will be void and its Linedefs will be one-sided:

../_images/vertices-void-sector.png

Linedefs

Linedefs divide the map into sectors, and they are also used to trigger actions.

Press l in the 2D view to enter Linedef edit mode.

../_images/linedefs.png

A Linedef also has a front and a back. You can tell the front of a Linedef by the direction of the protruding pin in the middle of the Linedef.

../_images/linedef-front.png

this Linedef front is facing down

Sectors

A sector is an area defined by multiple Linedefs.

Press s in the 2D view to enter Sector edit mode.

Press del to delete the highlighted sector. If the deleted sector is a child of a larger sector, it will be made void.

../_images/sectors.png

Things

Things represent players, monsters, pick-ups, obstacles, decorations, player start positions and teleport landing sites.

Press t in the 2D view to enter Things edit mode. space or ins inserts a new thing at the cursor position.

../_images/things.png

Multiple selections

While in the 2D view, you can select Vertices, Linedefs, Sectors and Things by:

  • Clicking an item to select/deselect it
  • Drag-select multiple items to include/exclude them in the selection
  • Hold shift to prevent moving things around when making a selection

Switching between Vertices, Linedefs and Sectors will preserve any selections as much as possible.

Deselecting

Press ` (back quote) in the 2D view to deselect everything.

Transformations

You can scale and rotate selected Sectors, Linedefs and Vertices.

Scale dialog

Select the sector, lines or vertices to transform. Open the menu item Edit -> Scale Objects or press F3 to show the scale dialog.

../_images/scale-selection.png

Four inner most vertices are selected

../_images/scale-dialog.png

Scaling the vertices by 50% on the x-axis

../_images/scale-result.png

Scale with the mouse

You can scale sectors, lines or vertices with the mouse, by holding the r key and moving the mouse cursor toward or away from the center of your selection.

Note

If you find mouse scaling is too sensitive, try moving the cursor away from the center of your selection, before pressing r. The scale factor is a function of distance from your cursor to the center of the selection, by putting some distance between your cursor and the selection you reduce that factor.

Rotate dialog

Click on Edit -> Rotate Object or press F4 to show the rotate dialog.

../_images/scale-selection.png

Four inner most vertices are selected

../_images/rotate-dialog.png

Rotating the vertices by 45 degrees

../_images/rotate-result.png

Rotate with the mouse

You can rotate sectors, lines or vertices with the mouse, by holding Ctrl+r and moving the mouse cursor toward or away from the center of your selection.

Note

If you find mouse rotation is too sensitive, try moving the cursor away from the center of your selection, before pressing Ctrl+r. The rotation factor is a function of distance from your cursor to the center of the selection, by putting some distance between your cursor and the selection you reduce that factor.

Textures

Sidedefs

A Sidedef refers to the texture data for a Linedef, it can have lower, middle and upper textures.

The relation of the Sidedefs are best illustrated with these poorly-matched textures:

../_images/textures-sidedefs-3d.png

Lower texture is COMPBLUE, middle is MIDGRATE, and upper texture is BRICK10

To change the Sidedefs

  • Switch to 2D mode
  • Enter Linedef mode (l)
  • Select one (or more) Linedefs
../_images/textures-selection.png
  • Click the “Front Sidedef” texture button to open the texture browser
  • (optionally) Press tab to switch to 3D view for a live preview
  • Select a texture in the browser window
../_images/textures-browser.png

Floor / ceiling textures

Enter Sector editing mode and select the sector to change:

../_images/floor-ceil-texture-2d.png

Click the texture buttons to open the texture browser:

../_images/floor-ceil-buttons-closeup.png

You can enter the 3D view to see a preview of the texture changes:

../_images/floor-ceil-browser.png