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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
using MS.Internal;
namespace System.Windows.Media.Imaging
{
#region BitmapSizeOptions
/// <summary>
/// Sizing options for an bitmap. The resulting bitmap
/// will be scaled based on these options.
/// </summary>
public class BitmapSizeOptions
{
/// <summary>
/// Construct an BitmapSizeOptions object. Still need to set the Width and Height Properties.
/// </summary>
private BitmapSizeOptions()
{
}
/// <summary>
/// Whether or not to preserve the aspect ratio of the original
/// bitmap. If so, then the PixelWidth and PixelHeight are
/// maximum values for the bitmap size. The resulting bitmap
/// is only guaranteed to have either its width or its height
/// match the specified values. For example, if you want to
/// specify the height, while preserving the aspect ratio for
/// the width, then set the height to the desired value, and
/// set the width to Int32.MaxValue.
///
/// If we are not to preserve aspect ratio, then both the
/// specified width and the specified height are used, and
/// the bitmap will be stretched to fit both those values.
/// </summary>
public bool PreservesAspectRatio
{
get
{
return _preservesAspectRatio;
}
}
/// <summary>
/// PixelWidth of the resulting bitmap. See description of
/// PreserveAspectRatio for how this value is used.
///
/// PixelWidth must be set to a value greater than zero to be valid.
/// </summary>
public int PixelWidth
{
get
{
return _pixelWidth;
}
}
/// <summary>
/// PixelHeight of the resulting bitmap. See description of
/// PreserveAspectRatio for how this value is used.
///
/// PixelHeight must be set to a value greater than zero to be valid.
/// </summary>
public int PixelHeight
{
get
{
return _pixelHeight;
}
}
/// <summary>
/// Rotation to rotate the bitmap. Only multiples of 90 are supported.
/// </summary>
public Rotation Rotation
{
get
{
return _rotationAngle;
}
}
/// <summary>
/// Constructs an identity BitmapSizeOptions (when passed to a TransformedBitmap, the
/// input is the same as the output).
/// </summary>
public static BitmapSizeOptions FromEmptyOptions()
{
BitmapSizeOptions sizeOptions = new BitmapSizeOptions();
sizeOptions._rotationAngle = Rotation.Rotate0;
sizeOptions._preservesAspectRatio = true;
sizeOptions._pixelHeight = 0;
sizeOptions._pixelWidth = 0;
return sizeOptions;
}
/// <summary>
/// Constructs an BitmapSizeOptions that preserves the aspect ratio and enforces a height of pixelHeight.
/// </summary>
/// <param name="pixelHeight">Height of the resulting Bitmap</param>
public static BitmapSizeOptions FromHeight(int pixelHeight)
{
ArgumentOutOfRangeException.ThrowIfNegativeOrZero(pixelHeight);
BitmapSizeOptions sizeOptions = new BitmapSizeOptions();
sizeOptions._rotationAngle = Rotation.Rotate0;
sizeOptions._preservesAspectRatio = true;
sizeOptions._pixelHeight = pixelHeight;
sizeOptions._pixelWidth = 0;
return sizeOptions;
}
/// <summary>
/// Constructs an BitmapSizeOptions that preserves the aspect ratio and enforces a width of pixelWidth.
/// </summary>
/// <param name="pixelWidth">Width of the resulting Bitmap</param>
public static BitmapSizeOptions FromWidth(int pixelWidth)
{
ArgumentOutOfRangeException.ThrowIfNegativeOrZero(pixelWidth);
BitmapSizeOptions sizeOptions = new BitmapSizeOptions();
sizeOptions._rotationAngle = Rotation.Rotate0;
sizeOptions._preservesAspectRatio = true;
sizeOptions._pixelWidth = pixelWidth;
sizeOptions._pixelHeight = 0;
return sizeOptions;
}
/// <summary>
/// Constructs an BitmapSizeOptions that does not preserve the aspect ratio and
/// instead uses dimensions pixelWidth x pixelHeight.
/// </summary>
/// <param name="pixelWidth">Width of the resulting Bitmap</param>
/// <param name="pixelHeight">Height of the resulting Bitmap</param>
public static BitmapSizeOptions FromWidthAndHeight(int pixelWidth, int pixelHeight)
{
ArgumentOutOfRangeException.ThrowIfNegativeOrZero(pixelWidth);
ArgumentOutOfRangeException.ThrowIfNegativeOrZero(pixelHeight);
BitmapSizeOptions sizeOptions = new BitmapSizeOptions();
sizeOptions._rotationAngle = Rotation.Rotate0;
sizeOptions._preservesAspectRatio = false;
sizeOptions._pixelWidth = pixelWidth;
sizeOptions._pixelHeight = pixelHeight;
return sizeOptions;
}
/// <summary>
/// Constructs an BitmapSizeOptions that does not preserve the aspect ratio and
/// instead uses dimensions pixelWidth x pixelHeight.
/// </summary>
/// <param name="rotation">Angle to rotate</param>
public static BitmapSizeOptions FromRotation(Rotation rotation)
{
switch(rotation)
{
case Rotation.Rotate0:
case Rotation.Rotate90:
case Rotation.Rotate180:
case Rotation.Rotate270:
break;
default:
throw new ArgumentException(SR.Image_SizeOptionsAngle, "rotation");
}
BitmapSizeOptions sizeOptions = new BitmapSizeOptions();
sizeOptions._rotationAngle = rotation;
sizeOptions._preservesAspectRatio = true;
sizeOptions._pixelWidth = 0;
sizeOptions._pixelHeight = 0;
return sizeOptions;
}
// Note: In this method, newWidth, newHeight are not affected by the
// rotation angle.
internal void GetScaledWidthAndHeight(
uint width,
uint height,
out uint newWidth,
out uint newHeight)
{
if (_pixelWidth == 0 && _pixelHeight != 0)
{
Debug.Assert(_preservesAspectRatio == true);
newWidth = (uint)((_pixelHeight * width)/height);
newHeight = (uint)_pixelHeight;
}
else if (_pixelWidth != 0 && _pixelHeight == 0)
{
Debug.Assert(_preservesAspectRatio == true);
newWidth = (uint)_pixelWidth;
newHeight = (uint)((_pixelWidth * height)/width);
}
else if (_pixelWidth != 0 && _pixelHeight != 0)
{
Debug.Assert(_preservesAspectRatio == false);
newWidth = (uint)_pixelWidth;
newHeight = (uint)_pixelHeight;
}
else
{
newWidth = width;
newHeight = height;
}
}
internal bool DoesScale
{
get
{
return (_pixelWidth != 0 || _pixelHeight != 0);
}
}
internal WICBitmapTransformOptions WICTransformOptions
{
get
{
WICBitmapTransformOptions options = 0;
switch (_rotationAngle)
{
case Rotation.Rotate0:
options = WICBitmapTransformOptions.WICBitmapTransformRotate0;
break;
case Rotation.Rotate90:
options = WICBitmapTransformOptions.WICBitmapTransformRotate90;
break;
case Rotation.Rotate180:
options = WICBitmapTransformOptions.WICBitmapTransformRotate180;
break;
case Rotation.Rotate270:
options = WICBitmapTransformOptions.WICBitmapTransformRotate270;
break;
default:
Debug.Assert(false);
break;
}
return options;
}
}
private bool _preservesAspectRatio;
private int _pixelWidth;
private int _pixelHeight;
private Rotation _rotationAngle;
}
#endregion // BitmapSizeOptions
}
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