doomsday DEDs do NOT need to be compiled, in fact they can be edited while Doomsday is running and then re-read at any time. The disadvantage of this method is that in order to make changes to your DED you will need to close Doomsday, open DoomBuilder, edit your DED then save and start Doomsday again.

For information on a more flexible method to use whilest building your wad check the editing_deds_at_runtime HOWTO.

• Open DoomBuilder.

• Goto File and load in the map you want to edit (in my case mywad.wad).

The next dialog box you'll see will ask you to Select Map from mywad.wad.

• Click on the map you want to edit (in my case MAP01).

You'll also see a selection box with the label Game (this tells Doom Builder what game we are editing for).

• From here you need to select jDoom

• Click OK.

Now we're ready to start writing our DED. Let's do something cool like getting our name to show up at the start of the level and giving a sector some neat red lighting. This will show you two things:

A) How to write a DED

B) How to use XG to add red lighting to a sector

• Go to the file menu and click on Scripts.

This menu contains all the jDoom specific lumps that can be edited in Doom Builder (dd_xgdata has to be compiled so doesn't appear in this list).

• Click on DD_DEFNS.

You should now see DoomBuilder's Script window. Now because we haven't yet created a dd_defns lump you will now need to:

• Click the Make Script button.

This is where you can insert all your DED definitions and your XG line/sector classes. The first thing we are going to do is add the header. This isn't compulsory but I'm going to do it anyway:

• Type the following:

Header { Version = 6 }

Now lets add the name of the map and our name, so they appear at the start of the level! The following code might look alien to you but don't worry about that at the moment ( check out map_info_ded_ for more information on this class ).

• Type the following starting on a new line:

Map Info {

		 ID = "MAP01"
		 Name = "This is the name of the level"
		 Author = "This is MY name" 
		 Sky Layer 1 {
			 Flags = enable
			 Texture = "SKY1"
		 }
	 }

Now lets make that sector with the red lighting I mentioned earlier. This is a two stage process, we need to create a new SectorType then we need to attach it to our sector. Note the line that says ID = 8000, this is the number we'll use to attach our SectorType to our sector, so remember it for latter.

Again this will look totally alien but don't worry about that atm (check out the XG reference for more information on XG Line and Sector types).

• Type the following starting on a new line:

Sector Type { # My Red Light.

		 ID = 8000
		 Red fn = "z"
		 Green fn = "a"
		 Blue fn = "a"
	 }

Thats it. We've now finished creating our DD_DEFNS lump so we can now close the script editor:

• Click the Close button in the script editor dialog.

Now we need to attach our sector_type to a sector. Choose a sector you want your red light in.

• Right click the Sector to bring up the Edit Sector dialog.

Remember the ID of our new sector_type? It's 8000 in case you've forgotten.

• Enter 8000 where it says Sector Effect.
• Click Ok.

That's it. We've now finished setting our map up so all we need to do now is save our map and load up Doomsday.

• Goto the File menu and click Save.

Now load up Doomsday and revel in the glory of your name appearing at the start of the map and our cool red lighting.

• DoomBuilder
• DED reference
• XG reference