Transforms kullanarak ve kullanıcı denetimime atayarak düşük çözünürlüklü bir görüntü kırpıyorum

Question

Kullanıcı bir görüntüyü Stretch = Uniform ile yükleyen bir Windows 8.1 RT uygulaması üzerinde çalışıyorum. Görüntü mümkün olduğunca küçük ve olabildiğince büyük olabilir. Kırpma, kullanıcı kontrolümde gerçekleşir ve ekrana/resme dokunup basılı tuttuğumda kullanıcı kontrolüm görünür. Kırpma, parmağım/fareyi arka planda bulunan resmin üzerine dokunduğumda ve tuttuğumda gerçekleşir.

Sorunları Karşılıklı olan

uygulaması Emülatörü'nde ilk kez yüklenir ve musluk/tıklama ve tutma gerçekleştirilir ilk kez Ne zaman

1. , kullanıcı kontrolü belirir Ekranda sol üstte ve sonra tıklanan/tut alanımın üstünde geliyor. İhtiyacım olan şey, her nerede tıklamam ve tuttuğum her zaman ve her tıklattığımda görünmelidir. Parmağı/fareyi serbest bırakmak üzerine, çökmesi gerekir.

2. Ben dönüşümümerkezini kullanıyorum. Faremin şu anda kullanıcı denetiminin merkez tam olarak görüntüleneceği bölgeyi (piksel) istiyorum. Eğer 480 * 800 küçük çözünürlüklü bir görüntü yüklüyorsam ya da daha da küçükse, faremin bölgesi gelmiyor merkeze. Daha net olmak gerekirse, insan gözünün CORNEA numarasına dokunup basılı tuttuğumu hayal edin. Kornea, kullanıcı kontrolünün ortasında gösterilmeli ve yukarıdaki bölüm, bölümün geri kalan kısmını kapsamalıdır.

   1. Denetimimin görüntü sınırımın dışına çıkmasını istemiyorum, faremin resmin son pikseli varsa, resmin bir kısmı ve arka planın bir kısmı olmalıdır. görüntülenen. video gösterildiği gibi

3. aşağıda tam kodunu bulun kontrolünü döndürmek gerekir.

MainPage.XAML

<Page 
    x:Class="App78.MainPage" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:local="using:App78" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    mc:Ignorable="d"> 

    <Grid 
     x:Name="LayoutGrid" 
     Margin="0,0" 
     Background="{ThemeResource ApplicationPageBackgroundThemeBrush}" 
     Holding="LayoutGrid_Holding" 
     PointerMoved="LayoutGrid_OnPointerMoved" 
     PointerWheelChanged="LayoutGrid_OnPointerWheelChanged" 
     PointerPressed="LayoutGrid_OnPointerPressed" 
     PointerReleased="LayoutGrid_OnPointerReleased"> 
     <Image 
      x:Name="BigImage" 
      HorizontalAlignment="Center" 
      VerticalAlignment="Center" 
      Stretch="Uniform" 
      Source="http://blog.al.com/space-news/2009/04/iss015e22574.jpg" /> 

     <local:Magnifier VerticalAlignment="Top" HorizontalAlignment="Left" x:Name="MagnifierTip" Visibility="Collapsed" /> 
    </Grid> 
</Page> 

MAINPAGE.XAML.CS

using System; 
using System.Diagnostics; 
using Windows.UI.Xaml.Controls; 
using Windows.UI.Xaml.Input; 
using Windows.UI.Xaml.Media; 
using Windows.UI.Xaml.Media.Imaging; 

namespace App78 
{ 
    public sealed partial class MainPage : Page 
    { 
     private double zoomScale = 2; 
     private double pointerX = 0; 
     private double pointerY = 0; 
     private const double MinZoomScale = .25; 
     private const double MaxZoomScale = 32; 


     public MainPage() 
     { 
      this.InitializeComponent(); 

      var bi = (BitmapImage)BigImage.Source; 
      bi.ImageOpened += bi_ImageOpened; 
      this.SizeChanged += MainPage_SizeChanged; 
     } 

     void MainPage_SizeChanged(object sender, Windows.UI.Xaml.SizeChangedEventArgs e) 
     { 
      this.UpdateImageLayout(); 
     } 

     void bi_ImageOpened(object sender, Windows.UI.Xaml.RoutedEventArgs e) 
     { 
      this.UpdateImageLayout(); 
     } 

     private void UpdateImageLayout() 
     { 
      var bi = (BitmapImage)BigImage.Source; 
      if (bi.PixelWidth < this.LayoutGrid.ActualWidth && 
       bi.PixelHeight < this.LayoutGrid.ActualHeight) 
      { 
       this.BigImage.Stretch = Stretch.None; 
      } 
      else 
      { 
       this.BigImage.Stretch = Stretch.Uniform; 
      } 

      this.UpdateMagnifier(); 
     } 

     private void LayoutGrid_OnPointerMoved(object sender, PointerRoutedEventArgs e) 
     { 
      //DV: If pointer is not in contact we can ignore it 
      if (!e.Pointer.IsInContact) { return; } 

      var point = e.GetCurrentPoint(this.LayoutGrid); 
      this.pointerX = point.Position.X; 
      this.pointerY = point.Position.Y; 
      this.UpdateMagnifier(); 
     } 

     private void UpdateMagnifier() 
     { 
      var bi = (BitmapImage)BigImage.Source; 

      double offsetX = 0; 
      double offsetY = 0; 
      double imageScale = 1; 

      var imageRatio = (double)bi.PixelWidth/bi.PixelHeight; 
      var gridRatio = this.LayoutGrid.ActualWidth/this.LayoutGrid.ActualHeight; 

      if (bi.PixelWidth < this.LayoutGrid.ActualWidth && 
       bi.PixelHeight < this.LayoutGrid.ActualHeight) 
      { 
       offsetX = 0.5 * (this.LayoutGrid.ActualWidth - bi.PixelWidth); 
       offsetY = 0.5 * (this.LayoutGrid.ActualHeight - bi.PixelHeight); 
       //imageScale = 1; - remains 
      } 
      else if (imageRatio < gridRatio) 
      { 
       offsetX = 0.5 * (this.LayoutGrid.ActualWidth - imageRatio * this.LayoutGrid.ActualHeight); 
       offsetY = 0; 
       imageScale = BigImage.ActualHeight/bi.PixelHeight; 
      } 
      else 
      { 
       offsetX = 0; 
       offsetY = 0.5 * (this.LayoutGrid.ActualHeight - this.LayoutGrid.ActualWidth/imageRatio); 
       imageScale = BigImage.ActualWidth/bi.PixelWidth; 
      } 

      //DV: This is probably not need anymore 
      //MagnifierTip.MagnifierTransform.X = this.pointerX; 
      //MagnifierTip.MagnifierTransform.Y = this.pointerY; 
      MagnifierTip.PositionTransform.X = (-this.pointerX + offsetX)/imageScale; 
      MagnifierTip.PositionTransform.Y = (-this.pointerY + offsetY)/imageScale; 

      //DV: I haven't tested the Scaling/Zoom 
      MagnifierTip.ZoomTransform.ScaleX = imageScale * zoomScale; 
      MagnifierTip.ZoomTransform.ScaleY = imageScale * zoomScale; 

      MagnifierTip.CenterTransform.X = MagnifierTip.MagnifierEllipse.ActualWidth/2 - MagnifierTip.MagnifierEllipse.StrokeThickness/2; 
      MagnifierTip.CenterTransform.Y = MagnifierTip.MagnifierEllipse.ActualHeight/2 - MagnifierTip.MagnifierEllipse.StrokeThickness/2; 

      //DV: I added a GlobalGrid Transform which translates every children 
      MagnifierTip.MagnifierTransformGrid.X = this.pointerX - (MagnifierTip.ActualWidth/2); 
      MagnifierTip.MagnifierTransformGrid.Y = this.pointerY - (MagnifierTip.ActualHeight); ; 

     } 

     private void LayoutGrid_OnPointerWheelChanged(object sender, PointerRoutedEventArgs e) 
     { 
      if (e.GetCurrentPoint(this.LayoutGrid).Properties.MouseWheelDelta > 0) 
      { 
       zoomScale = Math.Max(MinZoomScale, Math.Min(MaxZoomScale, zoomScale * 1.2)); 
      } 
      else 
      { 
       zoomScale = Math.Max(MinZoomScale, Math.Min(MaxZoomScale, zoomScale/1.2)); 
      } 

      this.UpdateMagnifier(); 
     } 


     //DV: Holding usually only works with touch https://msdn.microsoft.com/en-us/library/windows/apps/windows.ui.xaml.uielement.holding.aspx?f=255&MSPPError=-2147217396 
     private void LayoutGrid_Holding(object sender, HoldingRoutedEventArgs e) 
     { 
      // 
     } 

     //DV: pointer pressed supports both mouse and touch but fires immeadiatley. You'll have to figure out a delay strategy or using holding for touch and right click for mouse 
     private void LayoutGrid_OnPointerPressed(object sender, PointerRoutedEventArgs e) 
     { 
      MagnifierTip.Visibility = Windows.UI.Xaml.Visibility.Visible; 
     } 

     //DV: pointer released supports both mouse and touch. 
     private void LayoutGrid_OnPointerReleased(object sender, PointerRoutedEventArgs e) 
     { 
      MagnifierTip.Visibility = Windows.UI.Xaml.Visibility.Collapsed; 
     } 
    } 
} 

Magnifier.XAML

<UserControl 
    x:Class="App78.Magnifier" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:local="using:App78" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    mc:Ignorable="d" 
    Height="230" 
    Width="170"> 


    <Grid Height="230" Width="170"> 

     <!-- DV: This is the global transform I added --> 
     <Grid.RenderTransform> 
      <TransformGroup> 
       <TranslateTransform x:Name="MagnifierTransformGrid" x:FieldModifier="public"/> 
      </TransformGroup> 
     </Grid.RenderTransform> 
     <Ellipse Opacity="1" Visibility="Visible" Fill="{ThemeResource ApplicationPageBackgroundThemeBrush}" HorizontalAlignment="Center" VerticalAlignment="Top" IsHitTestVisible="False" Width="135" Height="128" StrokeThickness="3" Margin="0,17,0,0" /> 
     <Ellipse x:Name="MagnifierEllipse" x:FieldModifier="public" Opacity="1" Visibility="Visible" HorizontalAlignment="Left" VerticalAlignment="Top" IsHitTestVisible="False" Width="150" Height="150" Stroke="White" StrokeThickness="3" Margin="11,8,0,0" > 
      <Ellipse.Fill> 
       <ImageBrush 
        ImageSource="http://blog.al.com/space-news/2009/04/iss015e22574.jpg" 
        Stretch="None" 
        AlignmentX="Left" 
        AlignmentY="Top"> 
        <ImageBrush.Transform> 
         <TransformGroup> 
          <TranslateTransform x:FieldModifier="public" 
           x:Name="CenterTransform"/> 
          <TranslateTransform x:FieldModifier="public" 
           x:Name="PositionTransform"/> 
          <ScaleTransform x:FieldModifier="public" 
           x:Name="ZoomTransform"/> 
         </TransformGroup> 
        </ImageBrush.Transform> 
       </ImageBrush> 
      </Ellipse.Fill> 
     </Ellipse> 
     <Path Data="M25.533,0C15.457,0,7.262,8.199,7.262,18.271c0,9.461,13.676,19.698,17.63,32.338 c0.085,0.273,0.34,0.459,0.626,0.457c0.287-0.004,0.538-0.192,0.619-0.467c3.836-12.951,17.666-22.856,17.667-32.33 C43.803,8.199,35.607,0,25.533,0z M25.533,32.131c-7.9,0-14.328-6.429-14.328-14.328c0-7.9,6.428-14.328,14.328-14.328 c7.898,0,14.327,6.428,14.327,14.328C39.86,25.702,33.431,32.131,25.533,32.131z" 
       Fill="#FFF4F4F5" 
       Stretch="Fill" 
       Stroke="Black" 
       UseLayoutRounding="False" 
       Height="227" 
       Width="171" ></Path> 
    </Grid> 
</UserControl> 

Kolaylık için proje here'dan indirilebilir. Daha iyi anlamak için, bu video'u görmenizi isterim. Tam olarak benim uygulamak zorunda olduğum şey bu.

Answer 1

Bazı değişiklikler ve trigonometri here ile çalışıyorum.

MainPage.xaml

<Page 
    x:Class="MagnifierApp.MainPage" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:local="using:MagnifierApp" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    mc:Ignorable="d"> 

    <Grid 
     x:Name="LayoutGrid" 
     Margin="0,0" 
     Background="{ThemeResource ApplicationPageBackgroundThemeBrush}" 
     PointerMoved="LayoutGrid_OnPointerMoved" 
     PointerWheelChanged="LayoutGrid_OnPointerWheelChanged" 
     PointerPressed="LayoutGrid_OnPointerPressed" 
     PointerReleased="LayoutGrid_OnPointerReleased"> 
     <Image 
      x:Name="BigImage" 
      HorizontalAlignment="Center" 
      VerticalAlignment="Center" 
      Stretch="Uniform" 
      Source="http://blog.al.com/space-news/2009/04/iss015e22574.jpg" /> 
     <local:Magnifier 
      x:Name="MagnifierTip" 
      VerticalAlignment="Top" 
      HorizontalAlignment="Left" 
      Visibility="Collapsed" /> 
    </Grid> 
</Page> 

MainPage.xaml.cs

using System; 
using Windows.UI.Xaml.Controls; 
using Windows.UI.Xaml.Input; 
using Windows.UI.Xaml.Media; 
using Windows.UI.Xaml.Media.Imaging; 

namespace MagnifierApp 
{ 
    public sealed partial class MainPage : Page 
    { 
     private double zoomScale = 2; 
     private double pointerX = 0; 
     private double pointerY = 0; 
     private const double MinZoomScale = .25; 
     private const double MaxZoomScale = 32; 
     private bool isFirst = true; 

     public MainPage() 
     { 
      this.InitializeComponent(); 

      var bi = (BitmapImage)BigImage.Source; 
      bi.ImageOpened += bi_ImageOpened; 
      this.SizeChanged += MainPage_SizeChanged; 
     } 

     void MainPage_SizeChanged(object sender, Windows.UI.Xaml.SizeChangedEventArgs e) 
     { 
      this.UpdateImageLayout(); 
     } 

     void bi_ImageOpened(object sender, Windows.UI.Xaml.RoutedEventArgs e) 
     { 
      this.UpdateImageLayout(); 
     } 

     private void UpdateImageLayout() 
     { 
      var bi = (BitmapImage)BigImage.Source; 

      if (bi.PixelWidth < this.LayoutGrid.ActualWidth && 
       bi.PixelHeight < this.LayoutGrid.ActualHeight) 
      { 
       this.BigImage.Stretch = Stretch.None; 
      } 
      else 
      { 
       this.BigImage.Stretch = Stretch.Uniform; 
      } 

      this.UpdateMagnifier(); 
     } 

     private void LayoutGrid_OnPointerMoved(object sender, PointerRoutedEventArgs e) 
     { 
      if (!e.Pointer.IsInContact) 
      { 
       return; 
      } 

      var point = e.GetCurrentPoint(this.LayoutGrid); 
      this.pointerX = point.Position.X; 
      this.pointerY = point.Position.Y; 
      this.UpdateMagnifier(); 
     } 

     private void LayoutGrid_OnPointerWheelChanged(object sender, PointerRoutedEventArgs e) 
     { 
      if (e.GetCurrentPoint(this.LayoutGrid).Properties.MouseWheelDelta > 0) 
      { 
       zoomScale = Math.Max(MinZoomScale, Math.Min(MaxZoomScale, zoomScale * 1.2)); 
      } 
      else 
      { 
       zoomScale = Math.Max(MinZoomScale, Math.Min(MaxZoomScale, zoomScale/1.2)); 
      } 

      this.UpdateMagnifier(); 
     } 

     private void LayoutGrid_OnPointerPressed(object sender, PointerRoutedEventArgs e) 
     { 
      if (!e.Pointer.IsInContact) { return; } 

      var point = e.GetCurrentPoint(this.LayoutGrid); 

      this.pointerX = point.Position.X; 
      this.pointerY = point.Position.Y; 
      this.UpdateMagnifier(); 
      MagnifierTip.Visibility = Windows.UI.Xaml.Visibility.Visible; 
     } 

     private void LayoutGrid_OnPointerReleased(object sender, PointerRoutedEventArgs e) 
     { 
      MagnifierTip.Visibility = Windows.UI.Xaml.Visibility.Collapsed; 
     } 

     private void UpdateMagnifier() 
     { 
      var bi = (BitmapImage)BigImage.Source; 

      double offsetX; 
      double offsetY; 
      double imageScale; 
      CalculateImageScaleAndOffsets(bi, out offsetX, out offsetY, out imageScale); 

      MagnifierTip.PositionTransform.X = (-this.pointerX + offsetX)/imageScale; 
      MagnifierTip.PositionTransform.Y = (-this.pointerY + offsetY)/imageScale; 
      MagnifierTip.ZoomTransform.ScaleX = imageScale * zoomScale; 
      MagnifierTip.ZoomTransform.ScaleY = imageScale * zoomScale; 

      MagnifierTip.CenterTransform.X = MagnifierTip.MagnifierEllipse.ActualWidth/2 - MagnifierTip.MagnifierEllipse.StrokeThickness/2; 
      MagnifierTip.CenterTransform.Y = MagnifierTip.MagnifierEllipse.ActualHeight/2 - MagnifierTip.MagnifierEllipse.StrokeThickness/2; 

      MagnifierTip.MagnifierTranslateTransform.X = this.pointerX - (MagnifierTip.ActualWidth/2); 
      MagnifierTip.MagnifierTranslateTransform.Y = this.pointerY - (MagnifierTip.ActualHeight); 

      bool tooHigh = MagnifierTip.MagnifierTranslateTransform.Y < 0; 
      bool tooLeft = MagnifierTip.MagnifierTranslateTransform.X < 0; 
      bool tooRight = MagnifierTip.MagnifierTranslateTransform.X + MagnifierTip.ActualWidth > this.LayoutGrid.ActualWidth; 

      if (tooHigh || tooLeft || tooRight) 
      { 
       double angle = 0.0; 

       if (tooLeft && !tooHigh) 
       { 
        var dx = -MagnifierTip.MagnifierTranslateTransform.X; 
        var r = MagnifierTip.ActualHeight - MagnifierTip.ActualWidth/2; 
        var arad = Math.Asin(dx/r); 
        angle = arad * 180/Math.PI; 
       } 
       else if (tooLeft && tooHigh) 
       { 
        var dx = -MagnifierTip.MagnifierTranslateTransform.X; 
        var dy = -MagnifierTip.MagnifierTranslateTransform.Y; 
        var r = MagnifierTip.ActualHeight - MagnifierTip.ActualWidth/2; 
        var arad1 = Math.Asin(dx/r); 
        var arad2 = Math.Acos((r - dy)/r); 
        var arad = Math.Max(arad1, arad2); 
        angle = arad * 180/Math.PI; 
       } 
       else if (tooHigh && !tooRight) 
       { 
        var dy = -MagnifierTip.MagnifierTranslateTransform.Y; 
        var r = MagnifierTip.ActualHeight - MagnifierTip.ActualWidth/2; 
        var arad = Math.Acos((r - dy)/r); 

        if (MagnifierTip.MagnifierTranslateTransform.X + Math.Sin(arad) * r + MagnifierTip.ActualWidth > this.LayoutGrid.ActualWidth) 
        { 
         arad = -arad; 
        } 

        angle = arad * 180/Math.PI; 
       } 
       else if (tooHigh) 
       { 
        var dy = -MagnifierTip.MagnifierTranslateTransform.Y; 
        var dx = MagnifierTip.MagnifierTranslateTransform.X + MagnifierTip.ActualWidth - this.LayoutGrid.ActualWidth; 
        var r = MagnifierTip.ActualHeight - MagnifierTip.ActualWidth/2; 
        var arad1 = -Math.Acos((r - dy)/r); 
        var arad2 = -Math.Asin(dx/r); 
        var arad = Math.Min(arad1, arad2); 
        angle = arad * 180/Math.PI; 
       } 
       else //if (tooRight) 
       { 
        var dx = MagnifierTip.MagnifierTranslateTransform.X + MagnifierTip.ActualWidth - this.LayoutGrid.ActualWidth; 
        var r = MagnifierTip.ActualHeight - MagnifierTip.ActualWidth/2; 
        var arad = -Math.Asin(dx/r); 
        angle = arad * 180/Math.PI; 
       } 

       MagnifierTip.RotateTransform.Angle = angle; 
       MagnifierTip.LensRotateTransform.Angle = -angle; 
      } 
      else 
      { 
       MagnifierTip.RotateTransform.Angle = 0; 
       MagnifierTip.LensRotateTransform.Angle = 0; 
      } 
     } 

     private void CalculateImageScaleAndOffsets(BitmapImage bi, out double offsetX, out double offsetY, out double imageScale) 
     { 
      var imageRatio = (double)bi.PixelWidth/bi.PixelHeight; 
      var gridRatio = this.LayoutGrid.ActualWidth/this.LayoutGrid.ActualHeight; 

      if (bi.PixelWidth < this.LayoutGrid.ActualWidth && 
       bi.PixelHeight < this.LayoutGrid.ActualHeight) 
      { 
       offsetX = 0.5 * (this.LayoutGrid.ActualWidth - bi.PixelWidth); 
       offsetY = 0.5 * (this.LayoutGrid.ActualHeight - bi.PixelHeight); 
       imageScale = 1; 
      } 
      else if (imageRatio < gridRatio) 
      { 
       offsetX = 0.5 * (this.LayoutGrid.ActualWidth - imageRatio * this.LayoutGrid.ActualHeight); 
       offsetY = 0; 
       imageScale = BigImage.ActualHeight/bi.PixelHeight; 
      } 
      else 
      { 
       offsetX = 0; 
       offsetY = 0.5 * (this.LayoutGrid.ActualHeight - this.LayoutGrid.ActualWidth/imageRatio); 
       imageScale = BigImage.ActualWidth/bi.PixelWidth; 
      } 
     } 
    } 
} 

Magnifier.xaml

<UserControl 
    x:Class="MagnifierApp.Magnifier" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:local="using:MagnifierApp" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    mc:Ignorable="d" 
    Height="227" 
    Width="170"> 
    <Grid 
     Height="227" 
     Width="170" 
     RenderTransformOrigin="0.5,1"> 
     <Grid.RenderTransform> 
      <TransformGroup> 
       <RotateTransform 
        x:FieldModifier="public" 
        x:Name="RotateTransform" 
        Angle="0" /> 
       <TranslateTransform 
        x:Name="MagnifierTranslateTransform" 
        x:FieldModifier="public" /> 
      </TransformGroup> 
     </Grid.RenderTransform> 
     <Ellipse 
      HorizontalAlignment="Left" 
      VerticalAlignment="Top" 
      IsHitTestVisible="False" 
      Width="152" 
      Height="152" 
      Fill="{ThemeResource ApplicationPageBackgroundThemeBrush}" 
      Margin="9,10,0,0" 
      RenderTransformOrigin="0.5,0.5" 
      StrokeThickness="0"> 
     </Ellipse> 
     <Ellipse 
      x:Name="MagnifierEllipse" 
      x:FieldModifier="public" 
      HorizontalAlignment="Left" 
      VerticalAlignment="Top" 
      IsHitTestVisible="False" 
      Width="152" 
      Height="152" 
      Stroke="White" 
      Margin="9,10,0,0" 
      RenderTransformOrigin="0.5,0.5" 
      StrokeThickness="0"> 
      <Ellipse.RenderTransform> 
       <RotateTransform 
        x:FieldModifier="public" 
        x:Name="LensRotateTransform" 
        Angle="0" /> 
      </Ellipse.RenderTransform> 
      <Ellipse.Fill> 
       <ImageBrush 
        ImageSource="http://blog.al.com/space-news/2009/04/iss015e22574.jpg" 
        Stretch="None" 
        AlignmentX="Left" 
        AlignmentY="Top"> 
        <ImageBrush.Transform> 
         <TransformGroup> 
          <TranslateTransform 
           x:FieldModifier="public" 
           x:Name="PositionTransform" /> 
          <ScaleTransform 
           x:FieldModifier="public" 
           x:Name="ZoomTransform" /> 
          <TranslateTransform 
           x:FieldModifier="public" 
           x:Name="CenterTransform" /> 
         </TransformGroup> 
        </ImageBrush.Transform> 
       </ImageBrush> 
      </Ellipse.Fill> 
     </Ellipse> 
     <Path 
      Data="M85,11 C43.8548,11 10.5,44.3548 10.5,85.5 C10.5,126.645 43.8548,160 85,160 C126.145,160 159.5,126.645 159.5,85.5 C159.5,44.3548 126.145,11 85,11 z M85,0.5 C131.668,0.5 169.5,38.3319 169.5,85 C169.5,103.959 163.256,121.459 152.713,135.558 L151.895,136.625 L152,136.625 L84.2999,226 L18,136.625 L18.1054,136.625 L17.2872,135.558 C6.74375,121.459 0.5,103.959 0.5,85 C0.5,38.3319 38.3319,0.5 85,0.5 z" 
      Margin="0,0.5,0,0" 
      Stretch="Fill" 
      Stroke="Black" 
      UseLayoutRounding="False" 
      StrokeThickness="0" 
      Fill="White" /> 
    </Grid> 
</UserControl> 

Answer 2

1 için düzeltme burada

LayoutGrid_OnPointerPressed 

içinde bile Yani güncellenen yöntem

private void LayoutGrid_OnPointerPressed(object sender, PointerRoutedEventArgs e) 
     { 
      MagnifierTip.Visibility = Windows.UI.Xaml.Visibility.Visible; 

      var point = e.GetCurrentPoint(this.LayoutGrid); 
      this.pointerX = point.Position.X; 
      this.pointerY = point.Position.Y; 
      this.UpdateMagnifier(); 
     } 

Bu size bahsediyorsun istenilen davranışı verir benziyor büyüteç güncelleyin etmektir. sınırları sorunu

çözme için

BitImage yerine LayoutGrid ile ilgili olarak yukarıda işaretçi değerlerini hesaplar.

(this.pointerX < 0.0 || this.pointerY < 0.0) dönüş ise; (this.pointerX> BigImage.ActualWidth || this.pointerY> BigImage.ActualHeight) dönüş; var bi = (BitmapImage) BigImage.Source;

Kenarları kapatırken döndürme, dönme açısının kenara ulaştığı ve dönme dönüşümünü uygulayarak dikkatle hesaplanmasıyla ilgilidir.

MagnifierTip.RenderTransform = new RotateTransform{Angle=<CalculatedValue>, CenterX=<CalculatedValue>, CenterY=<CalculatedValue>}; 

Bu yardımcı olur umarım.