Added file include/convert_from_iu.h left out of last commit.

include/convert_from_iu.h

+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright (C) 2012 CERN
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you may find one here:
+ * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+ * or you may search the http://www.gnu.org website for the version 2 license,
+ * or you may write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
+/**
+ * @file convert_from_iu.h
+ * @brief Definitions and functions to convert from internal units to user units
+ *        depending upon the application and/or build options.
+ */
+
+
+#ifndef _CONVERT_FROM_IU_
+#define _CONVERT_FROM_IU_
+
+#include <config.h>     // USE_PCBNEW_NANOMETRES is defined here
+
+/// Convert from internal units to user units.
+#if defined(PCBNEW) || defined(CVPCB) || defined(GERBVIEW)
+    #if defined( USE_PCBNEW_NANOMETRES )
+    #if defined(GERBVIEW)
+        #define MM_PER_IU   1.0 / 1e5         // Gerbview uses 10 micrometer.
+    #else
+        #define MM_PER_IU   1.0 / 1e6         // Pcbnew in nanometers.
+    #endif
+    #define MILS_PER_IU ( MM_PER_IU * 0.0254 )
+    #define DECIMILS_PER_IU (MM_PER_IU * 0.00254 )
+    #else                                     // Pcbnew in deci-mils.
+        #define DECIMILS_PER_IU  1
+        #define MILS_PER_IU   10.0
+        #define MM_PER_IU   (1e4 / 25.4)
+    #endif
+
+/// Convert PCBNEW internal units (iu) to mils.
+inline int Iu2Mils( int iu )
+{
+#if defined( USE_PCBNEW_NANOMETRES )
+    double x = iu * MILS_PER_IU;
+    return int( x < 0 ? x - 0.5 : x + 0.5 );
+#else
+    return iu * MILS_PER_IU;
+#endif
+}
+
+/// Convert PCBNEW internal units (iu) to deci-mils.
+inline int Iu2DMils( int iu )
+{
+#if defined( USE_PCBNEW_NANOMETRES )
+    double x = iu * DECIMILS_PER_IU;
+    return int( x < 0 ? x - 0.5 : x + 0.5 );
+#else
+    return iu;
+#endif
+}
+
+#else            // Eeschema and anything else.
+#define MILS_PER_IU   1.0
+#define MM_PER_IU   (MILS_PER_IU / 0.0254)
+
+inline int Iu2Mils( int iu )
+{
+    return iu;
+}
+#endif
+
+#endif  // #define _CONVERT_FROM_IU_