Utilize SGBucket::get_corner when building clip rectangles in

ogr-decode, genapts, and tg-construct.

src/BuildTiles/Main/tgconstruct_clip.cxx

@@ -28,6 +28,7 @@
 
 #include <terragear/tg_accumulator.hxx>
 #include <terragear/tg_shapefile.hxx>
+#include <terragear/tg_misc.hxx>
 
 #include "tgconstruct.hxx"
 
@@ -39,32 +40,28 @@ bool TGConstruct::ClipLandclassPolys( void ) {
     tgPolygon safety_base;
     tgcontour_list slivers;
     SGGeod p;
-    SGVec2d min, max;
     bool debug_area, debug_shape;
     static int accum_idx = 0;
-
-    // Get clip bounds
-    min.x() = bucket.get_center_lon() - 0.5 * bucket.get_width();
-    min.y() = bucket.get_center_lat() - 0.5 * bucket.get_height();
-    max.x() = bucket.get_center_lon() + 0.5 * bucket.get_width();
-    max.y() = bucket.get_center_lat() + 0.5 * bucket.get_height();
-
     tgAccumulator accum;
 
     // set up clipping tile : and remember to add the nodes!
-    p = SGGeod::fromDegM( min.x(), min.y(), -9999.0 );
+    p = bucket.get_corner( SG_BUCKET_SW );
+    p.setElevationM( -9999.0 );
     safety_base.AddNode( 0, p );
     nodes.unique_add( p );
 
-    p = SGGeod::fromDegM( max.x(), min.y(), -9999.0 );
+    p = bucket.get_corner( SG_BUCKET_SE );
+    p.setElevationM( -9999.0 );
     safety_base.AddNode( 0, p );
     nodes.unique_add( p );
 
-    p = SGGeod::fromDegM( max.x(), max.y(), -9999.0 );
+    p = bucket.get_corner( SG_BUCKET_NE );
+    p.setElevationM( -9999.0 );
     safety_base.AddNode( 0, p );
     nodes.unique_add( p );
 
-    p = SGGeod::fromDegM( min.x(), max.y(), -9999.0 );
+    p = bucket.get_corner( SG_BUCKET_NW );
+    p.setElevationM( -9999.0 );
     safety_base.AddNode( 0, p );
     nodes.unique_add( p );
 

src/Lib/terragear/tg_chopper.cxx

@@ -6,44 +6,21 @@
 #include <simgear/misc/sg_path.hxx>
 #include <simgear/io/lowlevel.hxx>
 
-
 #include "tg_chopper.hxx"
 #include "tg_shapefile.hxx"
-
+#include "tg_misc.hxx"
-unsigned int clip_num = 0;
 
 tgPolygon tgChopper::Clip( const tgPolygon& subject,
                       const std::string& type,
                       SGBucket& b )
 {
-    // p;
-
-    SGGeod min, max;
-    SGGeod c    = b.get_center();
-    double span = b.get_width();
     tgPolygon base, result;
 
-    // calculate bucket dimensions
+    // set up clipping tile : and remember to add the nodes!
-    if ( (c.getLatitudeDeg() >= -89.0) && (c.getLatitudeDeg() < 89.0) ) {
+    base.AddNode( 0, b.get_corner( SG_BUCKET_SW ) );
-        min = SGGeod::fromDeg( c.getLongitudeDeg() - span/2.0, c.getLatitudeDeg() - SG_HALF_BUCKET_SPAN );
+    base.AddNode( 0, b.get_corner( SG_BUCKET_SE ) );
-        max = SGGeod::fromDeg( c.getLongitudeDeg() + span/2.0, c.getLatitudeDeg() + SG_HALF_BUCKET_SPAN );
+    base.AddNode( 0, b.get_corner( SG_BUCKET_NE ) );
-    } else if ( c.getLatitudeDeg() < -89.0) {
+    base.AddNode( 0, b.get_corner( SG_BUCKET_NW ) );
-        min = SGGeod::fromDeg( -90.0, -180.0 );
-        max = SGGeod::fromDeg( -89.0,  180.0 );
-    } else if ( c.getLatitudeDeg() >= 89.0) {
-        min = SGGeod::fromDeg(  89.0, -180.0 );
-        max = SGGeod::fromDeg(  90.0,  180.0 );
-    } else {
-        SG_LOG( SG_GENERAL, SG_ALERT,  "Out of range latitude in clip_and_write_poly() = " << c.getLatitudeDeg() );
-    }
-
-    SG_LOG( SG_GENERAL, SG_DEBUG, "  (" << min << ") (" << max << ")" );
-
-    // set up clipping tile
-    base.AddNode( 0, SGGeod::fromDeg( min.getLongitudeDeg(), min.getLatitudeDeg()) );
-    base.AddNode( 0, SGGeod::fromDeg( max.getLongitudeDeg(), min.getLatitudeDeg()) );
-    base.AddNode( 0, SGGeod::fromDeg( max.getLongitudeDeg(), max.getLatitudeDeg()) );
-    base.AddNode( 0, SGGeod::fromDeg( min.getLongitudeDeg(), max.getLatitudeDeg()) );
 
     result = tgPolygon::Intersect( subject, base );    
     if ( result.Contours() > 0 ) {
@@ -123,12 +100,10 @@ void tgChopper::Add( const tgPolygon& subject, const std::string& type )
 
         for ( int row = 0; row <= dy; row++ )
         {
-            // Generate a clip rectangle - add some buffer on top and bottom, so we don't clip directly on an edge when we 
+            // Generate a clip rectangle for the whole row
-            // clip the individual buckets
-            // TODO : May no longer be necessary
             SGBucket  b_clip      = sgBucketOffset( bb.getMin().getLongitudeDeg(), bb.getMin().getLatitudeDeg(), 0, row );
-            double    clip_bottom = b_clip.get_center_lat() - SG_HALF_BUCKET_SPAN; // + 0.01);
+            double    clip_bottom = b_clip.get_center_lat() - SG_HALF_BUCKET_SPAN;
-            double    clip_top    = b_clip.get_center_lat() + SG_HALF_BUCKET_SPAN; // + 0.01);
+            double    clip_top    = b_clip.get_center_lat() + SG_HALF_BUCKET_SPAN;
             tgPolygon clip_row, clipped;
 
             SG_LOG( SG_GENERAL, SG_DEBUG, "   CLIPPED row " << row << " center lat is " << b_clip.get_center_lat() << " clip_botton is " << clip_bottom << " clip_top is " << clip_top );
@@ -153,26 +128,6 @@ void tgChopper::Add( const tgPolygon& subject, const std::string& type )
                 clipped.SetFlag(type);
 
                 ClipRow( clipped, b_clip.get_center_lat(), type );
-
-#if 0
-                {
-                    char layer[32];
-                    char ds_name[64];
-                    sprintf(ds_name, "./stripped_%s", type.c_str() );
-
-                    sprintf(layer,   "orig_%d", clip_num );
-                    tgShapefile::FromPolygon( subject, ds_name, layer, "poly" );
-                    
-                    sprintf(layer,   "clip_row_%d", clip_num );
-                    tgShapefile::FromPolygon( clip_row, ds_name, layer, "poly" );
-
-                    sprintf(layer,   "result_%d", clip_num );
-                    tgShapefile::FromPolygon( clipped, ds_name, layer, "poly" );
-                    
-                    clip_num++;
-                }
-#endif
-
             }
         }
     }

src/Lib/terragear/tg_misc.hxx

@@ -3,6 +3,13 @@
 #include "clipper.hpp"
 #include "tg_rectangle.hxx"
 
+// SGBucket corners
+#define SG_BUCKET_SW    (0)
+#define SG_BUCKET_SE    (1)
+#define SG_BUCKET_NE    (2)
+#define SG_BUCKET_NW    (3)
+
+
 // SGGeod Cleanup
 SGGeod  SGGeod_snap( const SGGeod& in, double grid );