blob: f1ec616bb747e3c4e2a593f3d037a0fa5db75f62 [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(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);
}
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);
}
double GetHeaderFooterSegmentWidth(double page_width) {
// Interstice is left at both ends of the page as well as between
// each region, so 1 is added.
double total_interstice_width = (kSettingHeaderFooterHorizontalRegions + 1) *
kSettingHeaderFooterInterstice;
return (page_width - total_interstice_width) /
kSettingHeaderFooterHorizontalRegions;
}
} // namespace printing