From 810209f61391718e3babab0d99ab4a8b7e6a89f1 Mon Sep 17 00:00:00 2001
From: Eric Berberich <eric.berberich@cgal.org>
Date: Fri, 29 Jun 2012 16:03:33 +0000
Subject: [PATCH] some problem with Coerction traits: Explicit casts required

Needs some further investigation! Background: the new CMake scripts for CGAL
are more strict what comes to includes of external libs (and Core is
considered as an external lib now), thus the testsuite has shown errors
related to the 'hacks' here. But as far as I know, the Coercion_traits
should be able to solve these issues.
---
 Envelope_3/include/CGAL/Env_sphere_traits_3.h | 31 ++++++++++---------
 1 file changed, 17 insertions(+), 14 deletions(-)

diff --git a/Envelope_3/include/CGAL/Env_sphere_traits_3.h b/Envelope_3/include/CGAL/Env_sphere_traits_3.h
index 5ec8d3d382f..235719abc41 100644
--- a/Envelope_3/include/CGAL/Env_sphere_traits_3.h
+++ b/Envelope_3/include/CGAL/Env_sphere_traits_3.h
@@ -481,13 +481,17 @@ public:
           return o;
       	}
 
+        // EBEB 2012/06/29: Added because of
+        // no matching function for call to 'compare(CGAL::Env_sphere_traits_3<Conic_traits_2>::Rational&, int)
+        Rational zero(0);
+
         // if (a1==a2) and (b1==b2) (*) is a plane parallel to the xy-plane
         // and either all ellipse (which should be a circle) is the
         // intersection - in which case lc >= 0
         // or there is no intersection at all between the 2 half spheres -
         // in which case lc < 0
-        if (CGAL_NTS compare(a_diff, 0) == EQUAL &&
-            CGAL_NTS compare(b_diff, 0) == EQUAL)
+        if (CGAL_NTS compare(a_diff, zero) == EQUAL &&
+            CGAL_NTS compare(b_diff, zero) == EQUAL)
         {
           Sign sign_lc = CGAL_NTS sign(lc);
           if (sign_lc != NEGATIVE)
@@ -505,7 +509,7 @@ public:
         //    R*x^2 + S*y^2 + T*xy + U*x + V*y + W = 0
         Alg_point_2 source, target, pmid;
         int n_inter_points;
-        if (CGAL_NTS compare(lb, 0) != EQUAL)
+        if (CGAL_NTS compare(lb, zero) != EQUAL)
         {
           // Find the x-coordinates of the intersection points of the conic 
           // curve and the line y = -(la*x + lc) / lb:
@@ -550,24 +554,23 @@ public:
             CGAL_precondition(x_mid_n_y_points > 0);
 
             Algebraic y1 = x_mid_y_points[0].y(), y2 = x_mid_y_points[1].y();
-            if (CGAL_NTS compare (
-                    Algebraic(la)*x_mid + Algebraic(lb)*y1 + Algebraic(lc),
-                    0) == LARGER)
-            {
+            if (CGAL_NTS compare(Algebraic(la)*x_mid + Algebraic(lb)*y1 + Algebraic(lc),
+                                 Algebraic(0)
+                                 ) == LARGER)
+              {
               pmid = Alg_point_2(x_mid, y1);
             }
             else
             {
-              CGAL_assertion(CGAL_NTS compare 
-                     (Algebraic(la)*x_mid + Algebraic(lb)*y2 + Algebraic(lc),
-                      0) == LARGER);
+              CGAL_assertion(CGAL_NTS compare(Algebraic(la)*x_mid + Algebraic(lb)*y2 + Algebraic(lc),
+                                              Algebraic(0)) == LARGER);
               pmid = Alg_point_2(x_mid, y2);
             }
           }
         }
         else
         { // lb == 0
-          CGAL_assertion(CGAL_NTS compare(la, 0) != EQUAL);
+          CGAL_assertion(CGAL_NTS compare(la, zero) != EQUAL);
 
           // Find the intersection of the vertical line x = -lc / la:
           Rational inter_x = -lc/la;
@@ -610,7 +613,7 @@ public:
             Algebraic x1 = y_mid_x_points[0].x(), x2 = y_mid_x_points[1].x();
             if (CGAL_NTS compare(
                         Algebraic(la)*x1 + Algebraic(lb)*y_mid + Algebraic(lc),
-                        0) == LARGER)
+                        Algebraic(0)) == LARGER)
             {
               pmid = Alg_point_2(x1, y_mid);
             }
@@ -618,8 +621,8 @@ public:
             {
               CGAL_assertion(CGAL_NTS compare (
                         Algebraic(la)*x2 + Algebraic(lb)*y_mid + Algebraic(lc),
-                        0) == LARGER);
-              pmid = Alg_point_2(x2, y_mid);
+                        Algebraic(0)) == LARGER);
+              pmid = Alg_point_2(x2, Algebraic(y_mid));
             }
           }
         }