blob: 55826ff796039d8454ff3e21ad45bd8af06a28a2 [file] [log] [blame]
// Copyright (c) 2011 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"
#include "printing/print_job_constants.h"
namespace printing {
int ConvertUnit(double 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 ConvertPixelsToPoint(int pixels) {
return ConvertUnit(pixels, kPixelsPerInch, kPointsPerInch);
}
double ConvertPixelsToPointDouble(double pixels) {
return ConvertUnitDouble(pixels, kPixelsPerInch, kPointsPerInch);
}
double ConvertPointsToPixelDouble(double points) {
return ConvertUnitDouble(points, kPointsPerInch, kPixelsPerInch);
}
} // namespace printing