From: curt <curt>
Date: Fri, 19 Mar 1999 00:26:18 +0000 (+0000)
Subject: Fixed a clipping bug (polygons specified in wrong order).
X-Git-Url: https://git.mxchange.org/?a=commitdiff_plain;h=d3f68ace943bb33bc1ee5c6090df0f1864091834;p=flightgear.git

Fixed a clipping bug (polygons specified in wrong order).
Touched up a few compiler warnings.
---

diff --git a/Clipper/clipper.cxx b/Clipper/clipper.cxx
index 9cadba246..0a10f3276 100644
--- a/Clipper/clipper.cxx
+++ b/Clipper/clipper.cxx
@@ -122,11 +122,11 @@ bool FGClipper::load_polys(const string& path) {
 	    gpc_add_contour( poly, &v_list );
 
 	    int area = (int)poly_type;
-	    if ( area < FG_MAX_AREAS ) {
+	    if ( area < FG_MAX_AREA_TYPES ) {
 		polys_in.polys[area].push_back(poly);
 	    } else {
 		FG_LOG( FG_CLIPPER, FG_ALERT, "Polygon type out of range = " 
-			<< poly_type);
+			<< (int)poly_type);
 		exit(-1);
 	    }
 	}
@@ -143,7 +143,8 @@ bool FGClipper::load_polys(const string& path) {
 
 // Do actually clipping work
 bool FGClipper::clip_all(const point2d& min, const point2d& max) {
-    gpc_polygon accum, result_diff, result_union, tmp;
+    gpc_polygon accum, result_union, tmp;
+    gpc_polygon *result_diff;
     gpcpoly_iterator current, last;
 
     FG_LOG( FG_CLIPPER, FG_INFO, "Running master clipper" );
@@ -173,7 +174,7 @@ bool FGClipper::clip_all(const point2d& min, const point2d& max) {
     gpc_add_contour( &polys_in.safety_base, &v_list );
 
     // process polygons in priority order
-    for ( int i = 0; i < FG_MAX_AREAS; ++i ) {
+    for ( int i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
 
 	current = polys_in.polys[i].begin();
 	last = polys_in.polys[i].end();
@@ -183,22 +184,46 @@ bool FGClipper::clip_all(const point2d& min, const point2d& max) {
 
 #ifdef EXTRA_SAFETY_CLIP
 	    // clip to base tile
-	    gpc_polygon_clip(GPC_INT, &polys_in.safety_base, *current, &tmp);
+	    gpc_polygon_clip(GPC_INT, *current, &polys_in.safety_base, &tmp);
 #else
-	    &tmp = *current;
+	    tmp = *current;
 #endif
 
 	    // clip current polygon against previous higher priority
 	    // stuff
+	    result_diff = new gpc_polygon;
+	    result_diff->num_contours = 0;
+	    result_diff->contour = NULL;
+
 	    if ( accum.num_contours == 0 ) {
-		result_diff = tmp;
+		*result_diff = tmp;
 		result_union = tmp;
 	    } else {
-		gpc_polygon_clip(GPC_DIFF, &accum, &tmp, &result_diff);
-		gpc_polygon_clip(GPC_UNION, &accum, &tmp, &result_union);
+		gpc_polygon_clip(GPC_DIFF, &tmp, &accum, result_diff);
+		gpc_polygon_clip(GPC_UNION, &tmp, &accum, &result_union);
 	    }
-	    
-	    polys_clipped.polys[i].push_back(&result_diff);
+
+	    /*
+	    cout << "original contours = " << tmp.num_contours << endl;
+
+	    for ( int j = 0; j < tmp.num_contours; j++ ) {
+		for (int k = 0;k < tmp.contour[j].num_vertices;k++ ) {
+		    cout << tmp.contour[j].vertex[k].x << ","
+			 << tmp.contour[j].vertex[k].y << endl;
+		}
+	    }
+
+	    cout << "clipped contours = " << result_diff->num_contours << endl;
+
+	    for ( int j = 0; j < result_diff->num_contours; j++ ) {
+		for (int k = 0;k < result_diff->contour[j].num_vertices;k++ ) {
+		    cout << result_diff->contour[j].vertex[k].x << ","
+			 << result_diff->contour[j].vertex[k].y << endl;
+		}
+	    }
+	    */
+
+	    polys_clipped.polys[i].push_back(result_diff);
 	    accum = result_union;
 	}
     }
@@ -222,6 +247,10 @@ bool FGClipper::clip_all(const point2d& min, const point2d& max) {
 
 
 // $Log$
+// Revision 1.4  1999/03/19 00:26:18  curt
+// Fixed a clipping bug (polygons specified in wrong order).
+// Touched up a few compiler warnings.
+//
 // Revision 1.3  1999/03/17 23:48:58  curt
 // minor renaming and a bit of rearranging.
 //
diff --git a/Clipper/clipper.hxx b/Clipper/clipper.hxx
index 874d49485..469691a2a 100644
--- a/Clipper/clipper.hxx
+++ b/Clipper/clipper.hxx
@@ -57,7 +57,7 @@ typedef gpcpoly_container::iterator gpcpoly_iterator;
 typedef gpcpoly_container::const_iterator const_gpcpoly_iterator;
 
 
-#define FG_MAX_AREAS 20
+#define FG_MAX_AREA_TYPES 20
 #define EXTRA_SAFETY_CLIP
 #define FG_MAX_VERTICES 100000
 
@@ -70,7 +70,7 @@ public:
 
 class FGgpcPolyList {
 public:
-    gpcpoly_container polys[FG_MAX_AREAS];
+    gpcpoly_container polys[FG_MAX_AREA_TYPES];
     gpc_polygon safety_base;
 };
 
@@ -109,6 +109,10 @@ public:
 
 
 // $Log$
+// Revision 1.5  1999/03/19 00:26:19  curt
+// Fixed a clipping bug (polygons specified in wrong order).
+// Touched up a few compiler warnings.
+//
 // Revision 1.4  1999/03/18 04:31:10  curt
 // Let's not pass copies of huge structures on the stack ... ye might see a
 // segfault ... :-)