restore some part of the code to prevent an untwanted segmentationf fault.

[simgear.git] / simgear / sg_inlines.h

diff --git a/simgear/sg_inlines.h b/simgear/sg_inlines.h
index 0fc8676113eb5e1f8eb9731cf2f64151684f9808..5d47d594c8994ae629213d39822b7fddd58f6115 100644 (file)
--- a/simgear/sg_inlines.h
+++ b/simgear/sg_inlines.h
@@ -17,10 +17,9 @@
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 // Library General Public License for more details.
 //
-// You should have received a copy of the GNU Library General Public
-// License along with this library; if not, write to the
-// Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-// Boston, MA  02111-1307, USA.
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 //
 // $Id$
 
@@ -28,37 +27,77 @@
 #ifndef _SG_INLINES_H
 #define _SG_INLINES_H
 
+// return the sign of a value
 template <class T>
-inline const int SG_SIGN(const T x) {
+inline int SG_SIGN(const T x) {
     return x < T(0) ? -1 : 1;
 }
 
+// return the minimum of two values
 template <class T>
-inline const T SG_MIN2(const T a, const T b) {
+inline T SG_MIN2(const T a, const T b) {
     return a < b ? a : b;
 }
 
 // return the minimum of three values
 template <class T>
-inline const T SG_MIN3( const T a, const T b, const T c) {
+inline T SG_MIN3( const T a, const T b, const T c) {
     return (a < b ? SG_MIN2 (a, c) : SG_MIN2 (b, c));
 }
 
+// return the maximum of two values
 template <class T>
-inline const T SG_MAX2(const T a, const T b) {
+inline T SG_MAX2(const T a, const T b) {
     return  a > b ? a : b;
 }
 
 // return the maximum of three values
 template <class T>
-inline const T SG_MAX3 (const T a, const T b, const T c) {
+inline T SG_MAX3 (const T a, const T b, const T c) {
     return (a > b ? SG_MAX2 (a, c) : SG_MAX2 (b, c));
 }
 
-// 
+// return the minimum and maximum of three values
+template <class T>
+inline void SG_MIN_MAX3 ( T &min, T &max, const T a, const T b, const T c) {
+    if( a > b ) {
+        if( a > c ) {
+            max = a;
+            min = SG_MIN2 (b, c);
+        } else {
+            max = c;
+            min = SG_MIN2 (a, b);
+        }
+    } else {
+        if( b > c ) {
+            max = b;
+            min = SG_MIN2 (a, c);
+        } else {
+            max = c;
+            min = SG_MIN2 (a, b);
+        }
+    }
+}
+
+// swap two values
 template <class T>
 inline void SG_SWAP( T &a, T &b) {
     T c = a;  a = b;  b = c;
 }
 
+// clamp a value to lie between min and max
+template <class T>
+inline void SG_CLAMP_RANGE(T &x, const T min, const T max ) {
+    if ( x < min ) { x = min; }
+    if ( x > max ) { x = max; }
+}
+
+// normalize a value to lie between min and max
+template <class T>
+inline void SG_NORMALIZE_RANGE( T &val, const T min, const T max ) {
+    T step = max - min;
+    while( val >= max )  val -= step;
+    while( val < min ) val += step;
+};
+
 #endif // _SG_INLINES_H