Glass Effect Silverlight Charts

I was working on developing a dashboard where I had to use Microsoft Silverlight Toolkit to create bar charts, but none of the charts would give Glass look or effect, so I had to search a way to create the same on top of existing toolkit charts.

After so much of goggling about Slverlight styles & themes, finally I managed to get glass & cylinder effect on the bars like below.

Therefore I have written this article to help developers who are in need of this.

In Microsoft Silverlight Toolkit, every Bar ColumnSeries class has child called DataPointStyle which can be customized to get this effect.

Basically, there would be two layers for each datapoint, one to render the original color and second is to get the glass mask on top of it.

Here are the few samples with source code.



Glass Effect



Source Code :

  
   
    
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      105,2001
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      93,2006
      112,2007
      145,2008
      165,2009
     
   
   
    
 

Cylinder Effect



Source Code :

  
   
    
      100,2000
      105,2001
      10,2002
      88,2003
      150,2004
      125,2005
      93,2006
      112,2007
      145,2008
      165,2009
     
   
   
    
 

You can reach me at srikanthvemulapally@gmail.com for any queries.
Thanks.

Windows Logon API for .NET

When you are developing windows or web applications and there is need for validating user credentials (either local or domain), the 'LogonUser' API helps alot and it makes developers life much easier.

This API function accepts five parameters and one of them is 'out' parameter.

Public Declare Auto Function LogonUser Lib "advapi32.dll" (ByVal lpszUsername As [String], _
ByVal lpszDomain As [String], ByVal lpszPassword As [String], _
ByVal dwLogonType As Integer, ByVal dwLogonProvider As Integer, _
ByRef phToken As IntPtr) As Boolean

This function returns 'true' if the authentication was success and 'false' if failed. The good part about it is that, it returns a valid exception with relevant error message when it fails to authenticate provided credentials.

After successful authentication, the phToken parameter(ByRef phToken As IntPtr)would give handle to the token and it can be used to create any process from that context. If you just want to use this API for authentication, you can ignore it.

Here is the usage.

Public Declare Auto Function LogonUser Lib "advapi32.dll" (ByVal lpszUsername As [String], _
ByVal lpszDomain As [String], ByVal lpszPassword As [String], _
ByVal dwLogonType As Integer, ByVal dwLogonProvider As Integer, _
ByRef phToken As IntPtr) As Boolean

Private Function LoginUser(ByVal UserName As String, ByVal Password As String, ByVal Domain As String) As Boolean
Try
Dim tokenHandle As New IntPtr(0)
' Call LogonUser to obtain a handle to an access token.
Dim returnValue As Boolean = Authorization.LogonUser(UserName, Password, Domain, 2, 0, tokenHandle)

'check if logon successful
If returnValue = False Then
Dim ret As Integer = Marshal.GetLastWin32Error()
Throw New System.ComponentModel.Win32Exception(ret)
Exit Function
End If

Return True

Catch ex As Exception
'Here is where it returns relevant error message when the API fails to authenticate user.
'ex.Message
End Try
Return False
End Function

Kinect - Remove background of person

Microsoft Kinect SDK for Windows is now available as a free download via Microsoft Research, which will allow developers to create new uses for the motion-based system beyond gaming.

This is my first article on Kinect SDK. I have come up with a simple application created on C# using Kinect SDK.

You can check the prerequisites here for developing Kinect based application.

This application automatically identifies foreground object structure (human/any moving object) and removes its background and displays only object on the canvas.



I have attached the source code for your reference.

Link to project --> http://goo.gl/LB3LL

Source Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using Microsoft.Research.Kinect.Audio;
using Microsoft.Research.Kinect.Nui;
namespace KinectSample
{
/// 

/// Interaction logic for MainWindow.xaml
/// 
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}

private Runtime kinect;
private void OnWindowsLoaded(object sender, RoutedEventArgs e)
{
kinect = new Runtime();
kinect.Initialize(RuntimeOptions.UseColor | RuntimeOptions.UseSkeletalTracking | RuntimeOptions.UseDepthAndPlayerIndex);
kinect.DepthStream.Open(ImageStreamType.Depth, 2, ImageResolution.Resolution320x240, ImageType.DepthAndPlayerIndex);
kinect.VideoStream.Open(ImageStreamType.Video, 2, ImageResolution.Resolution640x480, ImageType.Color);
this.Person.Source = kinect.CreateLivePlayerRenderer();
}

private void OnWindowUnloaded(object sender, RoutedEventArgs e)
{
kinect.Uninitialize();
Environment.Exit(0);
}


}


public static class RuntimeExtensions
{
public static WriteableBitmap CreateLivePlayerRenderer(this Runtime runtime)
{
if (runtime.DepthStream.Width == 0)
throw new InvalidOperationException("Either open the depth stream before calling this method or use the overload which takes in the resolution that the depth stream will later be opened with.");
return runtime.CreateLivePlayerRenderer(runtime.DepthStream.Width, runtime.DepthStream.Height);
}
public static WriteableBitmap CreateLivePlayerRenderer(this Runtime runtime, int depthWidth, int depthHeight)
{
PlanarImage depthImage = new PlanarImage();
WriteableBitmap target = new WriteableBitmap(depthWidth, depthHeight, 96, 96, PixelFormats.Bgra32, null);
var depthRect = new System.Windows.Int32Rect(0, 0, depthWidth, depthHeight);

runtime.DepthFrameReady += (s, e) =>
{
depthImage = e.ImageFrame.Image;
//Debug.Assert(depthImage.Height == depthHeight && depthImage.Width == depthWidth);
};

runtime.VideoFrameReady += (s, e) =>
{
// don't do anything if we don't yet have a depth image
if (depthImage.Bits == null) return;

byte[] color = e.ImageFrame.Image.Bits;

byte[] output = new byte[depthWidth * depthHeight * 4];

// loop over each pixel in the depth image
int outputIndex = 0;
for (int depthY = 0, depthIndex = 0; depthY < depthHeight; depthY++)                 {                     for (int depthX = 0; depthX < depthWidth; depthX++, depthIndex += 2)                     {                         // combine the 2 bytes of depth data representing this pixel                         short depthValue = (short)(depthImage.Bits[depthIndex] | (depthImage.Bits[depthIndex + 1] << 8));                          // extract the id of a tracked player from the first bit of depth data for this pixel                         int player = depthImage.Bits[depthIndex] & 7;                          // find a pixel in the color image which matches this coordinate from the depth image                         int colorX, colorY;                         runtime.NuiCamera.GetColorPixelCoordinatesFromDepthPixel(                             e.ImageFrame.Resolution,                             e.ImageFrame.ViewArea,                             depthX, depthY, // depth coordinate                             depthValue,  // depth value                             out colorX, out colorY);  // color coordinate                          // ensure that the calculated color location is within the bounds of the image                         colorX = Math.Max(0, Math.Min(colorX, e.ImageFrame.Image.Width - 1));                         colorY = Math.Max(0, Math.Min(colorY, e.ImageFrame.Image.Height - 1));                          output[outputIndex++] = color[(4 * (colorX + (colorY * e.ImageFrame.Image.Width))) + 0];                         output[outputIndex++] = color[(4 * (colorX + (colorY * e.ImageFrame.Image.Width))) + 1];                         output[outputIndex++] = color[(4 * (colorX + (colorY * e.ImageFrame.Image.Width))) + 2];                         output[outputIndex++] = player > 0 ? (byte)255 : (byte)0;
}
}
target.WritePixels(depthRect, output, depthWidth * PixelFormats.Bgra32.BitsPerPixel / 8, 0);
};
return target;
}
}

}

Please feel free to contact me incase of any queries.