1 files changed, 42 insertions, 0 deletions
diff --git a/printing/units.cc b/printing/units.cc
new file mode 100644
index 0000000..5f543fe
--- /dev/null
+++ b/printing/units.cc
@@ -0,0 +1,42 @@
+// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "printing/units.h"
+
+#include "base/logging.h"
+
+namespace printing {
+
+int ConvertUnit(int value, int old_unit, int new_unit) {
+  DCHECK_GT(new_unit, 0);
+  DCHECK_GT(old_unit, 0);
+  // With integer arithmetic, to divide a value with correct rounding, you need
+  // to add half of the divisor value to the dividend value. You need to do the
+  // reverse with negative number.
+  if (value >= 0) {
+    return ((value * new_unit) + (old_unit / 2)) / old_unit;
+  } else {
+    return ((value * new_unit) - (old_unit / 2)) / old_unit;
+  }
+}
+
+double ConvertUnitDouble(double value, double old_unit, double new_unit) {
+  DCHECK_GT(new_unit, 0);
+  DCHECK_GT(old_unit, 0);
+  return value * new_unit / old_unit;
+}
+
+int ConvertMilliInchToHundredThousanthMeter(int milli_inch) {
+  // 1" == 25.4 mm
+  // 1" == 25400 um
+  // 0.001" == 25.4 um
+  // 0.001" == 2.54 cmm
+  return ConvertUnit(milli_inch, 100, 254);
+}
+
+int ConvertHundredThousanthMeterToMilliInch(int cmm) {
+  return ConvertUnit(cmm, 254, 100);
+}
+
+}  // namespace printing