Remove texture coordinates length calculations from certain places.

The width calculation is corrected now and should fix distorted
runway textures.
Hopefully we can get rid of this width mumbo-jumbo soon, too.
It has to stay for now as I found no solution.

src/Airports/GenAirports850/apt_math.cxx

@@ -232,16 +232,13 @@ void gen_tex_section( const TGPolygon& runway,
     // potential artifacts and we may add or remove points and need to
     // do new texture coordinate calcs later.
 
-    // we add 0.5m to the length for texture overlap.  This puts the
-    // lines on the texture back to the edge of the runway where they
-    // belong.
-    double len = length / 2.0 + 0.5;
+    double len = length / 2.0;
     double sect_len = len * ( endl_pct - startl_pct );
 
-    // we add 0.5m to both sides of the runway (4' total) for texture
+    // we add 0.6m to both sides of the runway (1.2m total) for texture
     // overlap.  This puts the lines on the texture back to the edge
     // of the runway where they belong.
-    double wid = width + 0.5;
+    double wid = width + 1.2;
     double sect_wid = wid * ( endw_pct - startw_pct );
 
     TGTexParams tp;

src/Airports/GenAirports850/rwy_gen.cxx

@@ -109,7 +109,7 @@ void Runway::gen_rw_marking( const TGPolygon& runway,
     }
 
     //Now create the sections of the runway type
-    double length = rwy.length / 2.0 + 0.5;
+    double length = rwy.length / 2.0;
 
     for ( int i=0; i < rw_marking_list.size(); ++i) {
 	    SG_LOG(SG_GENERAL, SG_INFO, "Runway section texture = " << rw_marking_list[i].tex << " lenght: " << rw_marking_list[i].size);
@@ -184,10 +184,7 @@ for ( int rwhalf=0; rwhalf<2; ++rwhalf ){
 	SG_LOG(SG_GENERAL, SG_DEBUG, " point = " << p);
     }
 
-    // we add 0.5m to the length for texture overlap.  This puts the
-    // lines on the texture back to the edge of the runway where they
-    // belong.
-    double length = rwy.length / 2.0 + 0.5;
+    double length = rwy.length / 2.0;
     if ( length < 3075 * SG_FEET_TO_METER ) {
         SG_LOG( SG_GENERAL, SG_ALERT,
 	        "Runway " << rwy.rwnum[0] << " is not long enough ("

src/Airports/GenAirports850/rwy_simple.cxx

@@ -67,10 +67,7 @@ for ( int rwhalf=0; rwhalf<2; ++rwhalf ){
     runway_half.add_node( 0, runway.get_pt(0, 5) );
     }
 
-    // we add 0.5m to the length for texture overlap.  This puts the
-    // lines on the texture back to the edge of the runway where they
-    // belong.
-    double length = rwy.length / 2.0 + 0.5;
+    double length = rwy.length / 2.0;
     double start1_pct = 0.0;
     double end1_pct = 0.0;
     double heading = 0.0;