= Fixing Landmarks =


Image of thing to try:

{{attachment:problem.jpg||width=400}}

=== When to Fix Landmarks ===

At the end of each tiling or iteration, a form of find_nofit (T or P) is used to check for bad landmarks. 

A common find_nofit output will look soemthing like this:

{{{
EQ0004:   cat 004.OOT 
EP0002:   cat 005.OOT 
EP0003:   cat 006.OOT 
EO0003:   cat 007.OOT 
EN0003: * cat 008.OOT 
EN0004: * cat 009.OOT 
EM0003: . cat 010.OOT 
EM0004: * cat 011.OOT 
132 deleted
   !  cat 132.OOTThe 
}}}

The Four main types of find_nofit outputs are:

 * ! - the landmark was deleted
 * . - the landmark has overlaps
 * (space) - the landmark has minor error (don't worry about it).
 * * - the landmark has a major error and must be fixed.

All errors are worth recording, but the only output from find_nofit that warrants serious concern is *. Whenever a * is present in the find_nofit output the landmark that * is associated with must be fixed. To fix bad land marks [[lithos.e|lithos]] is used in the working directory.

=== How to Fix Landmarks ===

Once a problem landmark is identified, the executable [[lithos.e|lithos]] can be entered in the working directory to fix the landmark. 

As an example, the landmark EM0004 in the find_nofit output above has major errors. To select this landmark the following commands are entered in the [[lithos.e|lithos]] executable:

{{{
i
EM0004
n
n
}}}

The output of these commands looks like this:

{{{
Current landmark = NONE  
Main Menu: Q 0123O IUCRSG NVAMBX DEPL FZH? i
 >i                                                                               

 Input 6-character landmark name.[Q]
EM0004
    -0.31014     0.47683    -0.31113     0.29307

 gc slope.pgm


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