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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef nsViewportInfo_h___
#define nsViewportInfo_h___
#include <stdint.h>
#include "mozilla/Attributes.h"
#include "Units.h"
/**
* Default values for the nsViewportInfo class.
*/
static const mozilla::LayoutDeviceToScreenScale kViewportMinScale(0.1f);
static const mozilla::LayoutDeviceToScreenScale kViewportMaxScale(10.0f);
static const mozilla::CSSIntSize kViewportMinSize(200, 40);
static const mozilla::CSSIntSize kViewportMaxSize(10000, 10000);
/**
* Information retrieved from the <meta name="viewport"> tag. See
* nsIDocument::GetViewportInfo for more information on this functionality.
*/
class MOZ_STACK_CLASS nsViewportInfo
{
public:
nsViewportInfo(const mozilla::ScreenIntSize& aDisplaySize,
const mozilla::CSSToScreenScale& aDefaultZoom,
bool aAllowZoom) :
mDefaultZoomValid(true),
mDefaultZoom(aDefaultZoom),
mAutoSize(true),
mAllowZoom(aAllowZoom)
{
mSize = mozilla::ScreenSize(aDisplaySize) / mDefaultZoom;
mozilla::CSSToLayoutDeviceScale pixelRatio(1.0f);
mMinZoom = pixelRatio * kViewportMinScale;
mMaxZoom = pixelRatio * kViewportMaxScale;
ConstrainViewportValues();
}
nsViewportInfo(const mozilla::CSSToScreenScale& aDefaultZoom,
const mozilla::CSSToScreenScale& aMinZoom,
const mozilla::CSSToScreenScale& aMaxZoom,
const mozilla::CSSSize& aSize,
bool aAutoSize,
bool aAllowZoom) :
mDefaultZoomValid(true),
mDefaultZoom(aDefaultZoom),
mMinZoom(aMinZoom),
mMaxZoom(aMaxZoom),
mSize(aSize),
mAutoSize(aAutoSize),
mAllowZoom(aAllowZoom)
{
ConstrainViewportValues();
}
bool IsDefaultZoomValid() const { return mDefaultZoomValid; }
mozilla::CSSToScreenScale GetDefaultZoom() const { return mDefaultZoom; }
mozilla::CSSToScreenScale GetMinZoom() const { return mMinZoom; }
mozilla::CSSToScreenScale GetMaxZoom() const { return mMaxZoom; }
mozilla::CSSSize GetSize() const { return mSize; }
bool IsAutoSizeEnabled() const { return mAutoSize; }
bool IsZoomAllowed() const { return mAllowZoom; }
private:
/**
* Constrain the viewport calculations from the
* nsIDocument::GetViewportInfo() function in order to always return
* sane minimum/maximum values.
*/
void ConstrainViewportValues();
// If the default zoom was specified and was between the min and max
// zoom values.
bool mDefaultZoomValid;
// Default zoom indicates the level at which the display is 'zoomed in'
// initially for the user, upon loading of the page.
mozilla::CSSToScreenScale mDefaultZoom;
// The minimum zoom level permitted by the page.
mozilla::CSSToScreenScale mMinZoom;
// The maximum zoom level permitted by the page.
mozilla::CSSToScreenScale mMaxZoom;
// The size of the viewport, specified by the <meta name="viewport"> tag.
mozilla::CSSSize mSize;
// Whether or not we should automatically size the viewport to the device's
// width. This is true if the document has been optimized for mobile, and
// the width property of a specified <meta name="viewport"> tag is either
// not specified, or is set to the special value 'device-width'.
bool mAutoSize;
// Whether or not the user can zoom in and out on the page. Default is true.
bool mAllowZoom;
};
#endif
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