====== Using file overlays ======
^ Author | [[user>Aaron]] |
^ Last updated | 3rd of May, 2010. |
^ PDF | {{:tutorials:l3dt:fileoverlay:fileoverlay.pdf|141kB}} |
In this tutorial I explain how to use the [[bundydocs>l3dt:algorithms:hf:fileoverlay|file overlay]] special terrain type. To use this tutorial, you will need at least v2.5 of L3DT.
===== What is a file overlay? =====
First things first; a file overlay is a terrain effect that adds onto the heightfield the contents of another heightfield, as loaded from a file. These are useful for adding pre-made features such as hills, mountains, volcanos, etc.
===== Part 1: Creating the overlays =====
In this tutorial, I'm going to create an overlay from the distinctive summit of [[wp>Mount_St._Helens|Mount St. Helens]], and also from some text in an image.
Firstly, for Mt. St. Helens I have downloaded the high-res DEM from [[http://www.ashundar.com/index.php?action=tpmod;dl=item151|Ashundar.com]] (thanks Oshyan!). A 10-metre resolution HFZ file is also available for download from the [[http://www.bundysoft.com/L3DT/downloads/examples/|examples page]] ([[http://www.bundysoft.com/L3DT/downloads/examples/MtStHelens_10m.hfz|direct link, 1.06Mb]]).
It's a very good idea for file overlays to be zero-altitude around the edges, so I've loaded the file in L3DT, and used the
//[[bundydocs>l3dt:userguide:ops:hf:v_scale|Operations->Heightfield->Change vertical range]]//, //[[bundydocs>l3dt:userguide:ops:hf:clip|Operations->Heightfield->Clip heightfield]]// and //[[bundydocs>l3dt:userguide:io:export:area|File->Export->Selected area]]// options to achieve the following result((Determining just how I've done this is left as an exercise for the reader ;-) )):
{{ :tutorials:l3dt:fileoverlay:st_helens_overlay.png?300 |:tutorials:l3dt:fileoverlay:st_helens_overlay.png}}
You may notice that the overlay is not square; that's cool, they don't have to be.
The second overlay I'm going to use in this tute is something I drew in paint.exe:
{{ :tutorials:l3dt:fileoverlay:helloworld.png?200 |:tutorials:l3dt:fileoverlay:helloworld.png}}
===== Part 2: Saving the overlays =====
For L3DT to use the overlays, they must be placed in L3DT's resources directory, which is:
^ Vista / Win7 | C:\Users\[user name]\L3DT\Resources\[L3DT version]\Overlays\ |
^ Win XP / 2000 | C:\Documents and Settings\[user name]\L3DT\Resources\[L3DT version]\Overlays\ |
L3DT supports the following formats for file overlays: HFF, HF2, HFZ, BT, TER, BMP, PNG, JPG.
===== Part 3: Using the overlay manager =====
To get these overlays into L3DT I have to use the [[bundydocs>l3dt:userguide:res:overlays:manager|file overlay manager]], which is opened using the '//Resources->Overlays->Overlay manager...//' menu option. Using the 'new' button I have created my overlays, set the file names, and set the other relevant settings ([[bundydocs>l3dt:algorithms:hf:fileoverlay|see the algorithms page]]).