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//---------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// Description: This file contains the implementation of LinearGradientBrush.
// The LinearGradientBrush is a GradientBrush which defines its
// Gradient as a linear interpolation between two parallel lines.
//
// History:
// 05/07/2003 : Microsoft - Created it.
// 09/21/2004 : timothyc - Added GradientStopCollection constructors.
//
//---------------------------------------------------------------------------
using MS.Internal;
using MS.Internal.PresentationCore;
using System;
using System.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Diagnostics;
using System.Reflection;
using System.Windows;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Runtime.InteropServices;
using System.Windows.Media.Composition;
using System.Security;
using System.Security.Permissions;
using SR=MS.Internal.PresentationCore.SR;
using SRID=MS.Internal.PresentationCore.SRID;
namespace System.Windows.Media
{
/// <summary>
/// LinearGradientBrush - This GradientBrush defines its Gradient as an interpolation
/// between two parallel lines.
/// </summary>
public sealed partial class LinearGradientBrush : GradientBrush
{
#region Constructors
/// <summary>
/// Default constructor for LinearGradientBrush. The resulting brush has no content.
/// </summary>
public LinearGradientBrush() : base()
{
}
/// <summary>
/// LinearGradientBrush Constructor
/// Constructs a LinearGradientBrush with GradientStops specified at offset 0.0 and
/// 1.0. The StartPoint is set to (0,0) and the EndPoint is derived from the angle
/// such that 1) the line containing the StartPoint and EndPoint is 'angle' degrees
/// from the horizontal in the direction of positive Y, and 2) the EndPoint lies on
/// the perimeter of the unit circle.
/// </summary>
/// <param name="startColor"> The Color at offset 0.0. </param>
/// <param name="endColor"> The Color at offset 1.0. </param>
/// <param name="angle"> The angle, in degrees, that the gradient will be away from horizontal. </param>
public LinearGradientBrush(Color startColor,
Color endColor,
double angle) : base()
{
EndPoint = EndPointFromAngle(angle);
GradientStops.Add(new GradientStop(startColor, 0.0));
GradientStops.Add(new GradientStop(endColor, 1.0));
}
/// <summary>
/// LinearGradientBrush Constructor
/// Constructs a LinearGradientBrush with two colors at the specified start and end points.
/// </summary>
/// <param name="startColor"> The Color at offset 0.0. </param>
/// <param name="endColor"> The Color at offset 1.0. </param>
/// <param name="startPoint"> The start point</param>
/// <param name="endPoint"> The end point</param>
public LinearGradientBrush(Color startColor,
Color endColor,
Point startPoint,
Point endPoint) : base()
{
StartPoint = startPoint;
EndPoint = endPoint;
GradientStops.Add(new GradientStop(startColor, 0.0));
GradientStops.Add(new GradientStop(endColor, 1.0));
}
/// <summary>
/// LinearGradientBrush Constructor
/// Constructs a LinearGradientBrush with GradientStops set to the passed-in collection.
/// </summary>
/// <param name="gradientStopCollection"> GradientStopCollection to set on this brush. </param>
public LinearGradientBrush(GradientStopCollection gradientStopCollection)
: base (gradientStopCollection)
{
}
/// <summary>
/// LinearGradientBrush Constructor
/// Constructs a LinearGradientBrush with GradientStops set to the passed-in collection.
/// Constructs a LinearGradientBrush with GradientStops specified at offset 0.0 and
/// 1.0. The StartPoint is set to (0,0) and the EndPoint is derived from the angle
/// such that 1) the line containing the StartPoint and EndPoint is 'angle' degrees
/// from the horizontal in the direction of positive Y, and 2) the EndPoint lies on
/// the perimeter of the unit circle.
/// </summary>
/// <param name="gradientStopCollection"> GradientStopCollection to set on this brush. </param>
/// <param name="angle"> The angle, in degrees, that the gradient will be away from horizontal. </param>
public LinearGradientBrush(GradientStopCollection gradientStopCollection,
double angle) : base (gradientStopCollection)
{
EndPoint = EndPointFromAngle(angle);
}
/// <summary>
/// LinearGradientBrush Constructor
/// Constructs a LinearGradientBrush with GradientStops set to the passed-in collection.
/// The StartPoint and EndPoint are set to the specified startPoint and endPoint.
/// </summary>
/// <param name="gradientStopCollection"> GradientStopCollection to set on this brush. </param>
/// <param name="startPoint"> The start point</param>
/// <param name="endPoint"> The end point</param>
public LinearGradientBrush(GradientStopCollection gradientStopCollection,
Point startPoint,
Point endPoint) : base (gradientStopCollection)
{
StartPoint = startPoint;
EndPoint = endPoint;
}
#endregion Constructors
/// <SecurityNote>
/// Critical: This code accesses unsafe code blocks
/// TreatAsSafe: This code does is safe to call but needs to be verified for correctness
/// </SecurityNote>
[SecurityCritical, SecurityTreatAsSafe]
private void ManualUpdateResource(DUCE.Channel channel, bool skipOnChannelCheck)
{
// If we're told we can skip the channel check, then we must be on channel
Debug.Assert(!skipOnChannelCheck || _duceResource.IsOnChannel(channel));
if (skipOnChannelCheck || _duceResource.IsOnChannel(channel))
{
Transform vTransform = Transform;
Transform vRelativeTransform = RelativeTransform;
GradientStopCollection vGradientStops = GradientStops;
DUCE.ResourceHandle hTransform;
if (vTransform == null ||
Object.ReferenceEquals(vTransform, Transform.Identity)
)
{
hTransform = DUCE.ResourceHandle.Null;
}
else
{
hTransform = ((DUCE.IResource)vTransform).GetHandle(channel);
}
DUCE.ResourceHandle hRelativeTransform;
if (vRelativeTransform == null ||
Object.ReferenceEquals(vRelativeTransform, Transform.Identity)
)
{
hRelativeTransform = DUCE.ResourceHandle.Null;
}
else
{
hRelativeTransform = ((DUCE.IResource)vRelativeTransform).GetHandle(channel);
}
DUCE.ResourceHandle hOpacityAnimations = GetAnimationResourceHandle(OpacityProperty, channel);
DUCE.ResourceHandle hStartPointAnimations = GetAnimationResourceHandle(StartPointProperty, channel);
DUCE.ResourceHandle hEndPointAnimations = GetAnimationResourceHandle(EndPointProperty, channel);
unsafe
{
DUCE.MILCMD_LINEARGRADIENTBRUSH data;
data.Type = MILCMD.MilCmdLinearGradientBrush;
data.Handle = _duceResource.GetHandle(channel);
double tempOpacity = Opacity;
DUCE.CopyBytes((byte*)&data.Opacity, (byte*)&tempOpacity, 8);
data.hOpacityAnimations = hOpacityAnimations;
data.hTransform = hTransform;
data.hRelativeTransform = hRelativeTransform;
data.ColorInterpolationMode = ColorInterpolationMode;
data.MappingMode = MappingMode;
data.SpreadMethod = SpreadMethod;
Point tempStartPoint = StartPoint;
DUCE.CopyBytes((byte*)&data.StartPoint, (byte*)&tempStartPoint, 16);
data.hStartPointAnimations = hStartPointAnimations;
Point tempEndPoint = EndPoint;
DUCE.CopyBytes((byte*)&data.EndPoint, (byte*)&tempEndPoint, 16);
data.hEndPointAnimations = hEndPointAnimations;
// NTRAID#Longhorn-1011154-2004/8/12-asecchia GradientStopCollection: Need to enforce upper-limit of gradient stop capacity
int count = (vGradientStops == null) ? 0 : vGradientStops.Count;
data.GradientStopsSize = (UInt32)(sizeof(DUCE.MIL_GRADIENTSTOP)*count);
channel.BeginCommand(
(byte*)&data,
sizeof(DUCE.MILCMD_LINEARGRADIENTBRUSH),
sizeof(DUCE.MIL_GRADIENTSTOP)*count
);
for (int i=0; i<count; i++)
{
DUCE.MIL_GRADIENTSTOP stopCmd;
GradientStop gradStop = vGradientStops.Internal_GetItem(i);
double temp = gradStop.Offset;
DUCE.CopyBytes((byte*)&stopCmd.Position,(byte*)&temp, sizeof(double));
stopCmd.Color = CompositionResourceManager.ColorToMilColorF(gradStop.Color);
channel.AppendCommandData(
(byte*)&stopCmd,
sizeof(DUCE.MIL_GRADIENTSTOP)
);
}
channel.EndCommand();
}
}
}
private Point EndPointFromAngle(double angle)
{
// Convert the angle from degrees to radians
angle = angle * (1.0/180.0) * System.Math.PI;
return (new Point(System.Math.Cos(angle), System.Math.Sin(angle)));
}
}
}
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