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//------------------------------------------------------------------------------
// Microsoft Avalon
// Copyright (c) Microsoft Corporation, All Rights Reserved.
//
// File: ImageSource.cs
//
//------------------------------------------------------------------------------
using System;
using System.Collections;
using System.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Reflection;
using MS.Internal;
using System.Diagnostics;
using System.Windows.Media;
using System.Globalization;
using System.Security;
using System.Security.Permissions;
using System.Runtime.InteropServices;
using System.Windows.Media.Animation;
using System.Windows.Media.Composition;
using System.Windows.Markup;
using MS.Win32;
namespace System.Windows.Media
{
#region ImageSource
/// <summary>
/// Interface for Bitmap Sources, included decoders and effects
/// </summary>
[TypeConverter(typeof(System.Windows.Media.ImageSourceConverter))]
[ValueSerializer(typeof(ImageSourceValueSerializer))]
[Localizability(LocalizationCategory.None, Readability = Readability.Unreadable)]
public abstract partial class ImageSource : Animatable
{
#region Constructor
/// <summary>
/// Don't allow 3rd party extensibility.
/// </summary>
internal ImageSource()
{
}
#endregion Constructor
/// <summary>
/// Get the width of the image in measure units (96ths of an inch).
/// </summary>
abstract public double Width
{
get;
}
/// <summary>
/// Get the height of the image in measure units (96ths of an inch).
/// </summary>
abstract public double Height
{
get;
}
/// <summary>
/// Get the metadata associated with this image source
/// </summary>
abstract public ImageMetadata Metadata
{
get;
}
/// <summary>
/// Get the Size associated with this image source
/// </summary>
internal virtual Size Size
{
get
{
return new Size(Width, Height);
}
}
#region ToInstanceDescriptor
/// <summary>
/// Can serialze "this" to a string
/// </summary>
internal virtual bool CanSerializeToString()
{
return false;
}
#endregion
/// <summary>
/// Converts pixels to DIPs in a way consistent with MIL. Protected here is okay
/// because ImageSource isn't extensible by 3rd parties.
/// </summary>
protected static double PixelsToDIPs(double dpi, int pixels)
{
// Obtain the natural size in MIL Device Independant Pixels (DIPs, or 1/96") of the bitmap.
// This is: (Bitmap Pixels) / (Bitmap DotsPerInch) * (DIPs per inch)
float dpif = (float)dpi;
// To be consistent with BitmapBrush
//
// Floating-point precision is used to maintain consistent
// logic with BitmapBrush DPI scaling, which is implemented in
// unmanaged code using single-precision math. Any changes to
// this logic must also be updated in the UCE BitmapBrush
// resource to maintain this consistency.
if (dpif < 0.0F || FloatUtil.IsCloseToDivideByZero(96.0F, dpif))
{
dpif = 96.0F;
}
return (double)(pixels * (96.0F / dpif));
}
}
#endregion // ImageSource
}
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