Fixed a serious bug caused by not-quite-correct comment/white space eating

which resulted in mismatched glBegin() glEnd() pairs, incorrect display lists,
and ugly display artifacts.

diff --git a/Objects/obj.cxx b/Objects/obj.cxx
index ac1ab9a1bd1ab204746e9448a35f1fc349a80feb..974ecd21ddc0736f5fcb9302a13d7bb3ba39d6ce 100644 (file)
--- a/Objects/obj.cxx
+++ b/Objects/obj.cxx
@@ -119,6 +119,8 @@ int fgObjLoad( const string& path, fgTILE *t) {
     double (*nodes)[3];
     fgPoint3d *center;
 
+    // printf("loading %s\n", path.c_str() );
+
     // Attempt to open "path.gz" or "path"
     fg_gzifstream in( path );
     if ( ! in )
@@ -144,13 +146,18 @@ int fgObjLoad( const string& path, fgTILE *t) {
 
     StopWatch stopwatch;
     stopwatch.start();
+
+    // ignore initial comments and blank lines. (priming the pump)
+    in.eat_comments();
+
     while ( ! in.eof() )
     {
-       // ignore comments and blank lines.
-       in.eat_comments();
 
        string token;
        in.stream() >> token;
+
+       // printf("token = %s\n", token.c_str() );
+
        if ( token == "gbs" )
        {
            // reference point (center offset)
@@ -202,6 +209,7 @@ int fgObjLoad( const string& path, fgTILE *t) {
                // close out the previous structure and start the next
                xglEnd();
                xglEndList();
+               // printf("xglEnd(); xglEndList();\n");
 
                // update fragment
                fragment.display_list = display_list;
@@ -212,8 +220,11 @@ int fgObjLoad( const string& path, fgTILE *t) {
                in_fragment = 1;
            }
 
+           // printf("start of fragment (usemtl)\n");
+
            display_list = xglGenLists(1);
            xglNewList(display_list, GL_COMPILE);
+           // printf("xglGenLists(); xglNewList();\n");
            in_faces = 0;
 
            // reset the existing face list
@@ -253,6 +264,7 @@ int fgObjLoad( const string& path, fgTILE *t) {
            // fgPrintf( FG_TERRAIN, FG_DEBUG, "(t) = ");
 
            xglBegin(GL_TRIANGLE_STRIP);
+           // printf("xglBegin(tristrip) %d %d %d\n", n1, n2, n3);
 
            odd = 1; 
            scale = 1.0;
@@ -279,7 +291,7 @@ int fgObjLoad( const string& path, fgTILE *t) {
                 pp = calc_tex_coords(nodes[n3], center);
                 xglTexCoord2f(pp.lon, pp.lat);
                // xglVertex3d(t->nodes[n3][0],t->nodes[n3][1],t->nodes[n3][2]);
-               xglVertex3dv(nodes[n3]);                
+               xglVertex3dv(nodes[n3]);
            } else {
                // Shading model is "GL_FLAT" so calculate per face
                // normals on the fly.
@@ -308,11 +320,27 @@ int fgObjLoad( const string& path, fgTILE *t) {
                // xglVertex3d(t->nodes[n3][0],t->nodes[n3][1],t->nodes[n3][2]);
                xglVertex3dv(nodes[n3]);                
            }
+           // printf("some normals, texcoords, and vertices\n");
 
            odd = 1 - odd;
            last1 = n2;
            last2 = n3;
 
+           // There can be three or four values 
+           char c;
+           while ( in.get(c) )
+           {
+               if ( c == '\n' )
+                   break; // only the one
+
+               if ( isdigit(c) )
+               {
+                   in.putback(c);
+                   in.stream() >> n4;
+                   break;
+               }
+           }
+
            if ( n4 > 0 ) {
                fragment.add_face(n3, n2, n4);
 
@@ -334,12 +362,14 @@ int fgObjLoad( const string& path, fgTILE *t) {
                odd = 1 - odd;
                last1 = n3;
                last2 = n4;
+               // printf("a normal, texcoord, and vertex (4th)\n");
            }
        } else if ( token[0] == 'f' ) {
            // unoptimized face
 
            if ( !in_faces ) {
                xglBegin(GL_TRIANGLES);
+               // printf("xglBegin(triangles)\n");
                in_faces = 1;
            }
 
@@ -367,6 +397,7 @@ int fgObjLoad( const string& path, fgTILE *t) {
             xglTexCoord2f(pp.lon, pp.lat);
            // xglVertex3d(t->nodes[n3][0], t->nodes[n3][1], t->nodes[n3][2]);
            xglVertex3dv(nodes[n3]);
+           // printf("some normals, texcoords, and vertices (tris)\n");
        } else if ( token[0] == 'q' ) {
            // continue a triangle strip
            n1 = n2 = 0;
@@ -400,7 +431,6 @@ int fgObjLoad( const string& path, fgTILE *t) {
            if ( shading ) {
                // Shading model is "GL_SMOOTH"
                MAT3_SCALE_VEC(normal, normals[n1], scale);
-               xglNormal3dv(normal);
            } else {
                // Shading model is "GL_FLAT"
                if ( odd ) {
@@ -411,14 +441,15 @@ int fgObjLoad( const string& path, fgTILE *t) {
                                approx_normal);
                }
                MAT3_SCALE_VEC(normal, approx_normal, scale);
-               xglNormal3dv(normal);
            }
+           xglNormal3dv(normal);
 
             pp = calc_tex_coords(nodes[n1], center);
             xglTexCoord2f(pp.lon, pp.lat);
            // xglVertex3d(t->nodes[n1][0], t->nodes[n1][1], t->nodes[n1][2]);
            xglVertex3dv(nodes[n1]);
-    
+           // printf("a normal, texcoord, and vertex (4th)\n");
+   
            odd = 1 - odd;
            last1 = last2;
            last2 = n1;
@@ -435,7 +466,6 @@ int fgObjLoad( const string& path, fgTILE *t) {
                if ( shading ) {
                    // Shading model is "GL_SMOOTH"
                    MAT3_SCALE_VEC(normal, normals[n2], scale);
-                   xglNormal3dv(normal);
                } else {
                    // Shading model is "GL_FLAT"
                    if ( odd ) {
@@ -446,13 +476,14 @@ int fgObjLoad( const string& path, fgTILE *t) {
                                    nodes[n2], approx_normal);
                    }
                    MAT3_SCALE_VEC(normal, approx_normal, scale);
-                   xglNormal3dv(normal);
                }
-
+               xglNormal3dv(normal);
+               
                pp = calc_tex_coords(nodes[n2], center);
                xglTexCoord2f(pp.lon, pp.lat);
                // xglVertex3d(t->nodes[n2][0],t->nodes[n2][1],t->nodes[n2][2]);
                xglVertex3dv(nodes[n2]);                
+               // printf("a normal, texcoord, and vertex (4th)\n");
 
                odd = 1 -odd;
                last1 = last2;
@@ -462,15 +493,17 @@ int fgObjLoad( const string& path, fgTILE *t) {
            fgPrintf( FG_TERRAIN, FG_WARN, "Unknown token in %s = %s\n", 
                      path.c_str(), token.c_str() );
        }
+
+       // eat comments and blank lines before start of while loop so
+       // if we are done with useful input it is noticed before hand.
+       in.eat_comments();
     }
-    stopwatch.stop();
-    fgPrintf( FG_TERRAIN, FG_INFO, "Loaded %s in %f seconds\n",
-             path.c_str(), stopwatch.elapsedSeconds() );
 
     if ( in_fragment ) {
        // close out the previous structure and start the next
        xglEnd();
        xglEndList();
+       // printf("xglEnd(); xglEndList();\n");
 
        // update fragment
        fragment.display_list = display_list;
@@ -494,11 +527,22 @@ int fgObjLoad( const string& path, fgTILE *t) {
     xglEnd();
     */   
 
+    stopwatch.stop();
+    fgPrintf( FG_TERRAIN, FG_INFO, "Loaded %s in %f seconds\n",
+             path.c_str(), stopwatch.elapsedSeconds() );
+
+    // printf("end of tile\n");
+
     return(1);
 }
 
 
 // $Log$
+// Revision 1.3  1998/09/03 21:27:03  curt
+// Fixed a serious bug caused by not-quite-correct comment/white space eating
+// which resulted in mismatched glBegin() glEnd() pairs, incorrect display lists,
+// and ugly display artifacts.
+//
 // Revision 1.2  1998/09/01 19:03:09  curt
 // Changes contributed by Bernie Bright <bbright@c031.aone.net.au>
 //  - The new classes in libmisc.tgz define a stream interface into zlib.