Random Bits

Updates

2010-04-24T19:51:00.001+05:30

Finally got time to update the expired video links (silverlight streaming) in my previous posts.

Setting into my new job , the future looks exciting, hopefully I will have time for some good posts.

ItemsControlMouseDragElementBehavior

2009-08-19T23:17:00.001+05:30

This is a Behavior I created to allow Drag and reposition items in WPF Control that extend ItemsControl. After applying this behavior the user can at runtime click and drag any item while holding the control key.

I created this behavior to support a application which required ability for the users to reposition items like icons on a desktop.

Here is the screen cast of the sample application demonstrating this.

Selective Debugging for WPF Binding

2009-08-17T18:49:00.001+05:30

Have you ever pulled out your hair trying to figure out why / why not a particular value is (or not) being set on your control , what was wrong with the binding?

I have seen people suggest exotic solutions where in there used a special converter so that they can debug the value being bound, or turn-on WPF tracing which generates a huge volume of trace statements that you will have to filter, well i found a easier way to debug just the one binding that matters by specifying a binding attribute.

        1: <UserControl

       2:     xmlns:diag="clr-namespace:System.Diagnostics;assembly=WindowsBase">

       3: ...

       4: ...

       5: <Grid>

       6:   <TextBlock VerticalAlignment="Center" Text="{Binding Name,diag:PresentationTraceSources.TraceLevel=High}"/>

       7: </Grid>

this produces following output in your trace log

       1: System.Windows.Data Warning: 54 :   Path: 'Name'

       2: System.Windows.Data Warning: 56 : BindingExpression (hash=42296571): Default mode resolved to OneWay

       3: System.Windows.Data Warning: 57 : BindingExpression (hash=42296571): Default update trigger resolved to PropertyChanged

       4: System.Windows.Data Warning: 58 : BindingExpression (hash=42296571): Attach to System.Windows.Controls.TextBlock.Text (hash=56437836)

       5: System.Windows.Data Warning: 63 : BindingExpression (hash=42296571): Resolving source 

       6: System.Windows.Data Warning: 66 : BindingExpression (hash=42296571): Found data context element: TextBlock (hash=56437836) (OK)

       7: System.Windows.Data Warning: 74 : BindingExpression (hash=42296571): Activate with root item CPUPlugin (hash=28857250)

       8: System.Windows.Data Warning: 104 : BindingExpression (hash=42296571):   At level 0 - for CPUPlugin.Name found accessor ReflectPropertyDescriptor(Name)

       9: System.Windows.Data Warning: 100 : BindingExpression (hash=42296571): Replace item at level 0 with CPUPlugin (hash=28857250), using accessor ReflectPropertyDescriptor(Name)

      10: System.Windows.Data Warning: 97 : BindingExpression (hash=42296571): GetValue at level 0 from CPUPlugin (hash=28857250) using ReflectPropertyDescriptor(Name): 'CPU'

      11: System.Windows.Data Warning: 76 : BindingExpression (hash=42296571): TransferValue - got raw value 'CPU'

      12: System.Windows.Data Warning: 85 : BindingExpression (hash=42296571): TransferValue - using final value 'CPU'

Cool Stop motion video made with Post it notes

2009-06-12T11:16:00.001+05:30

and here is how it was made…

Sliverlight Application Framework

2009-06-10T16:36:00.000+05:30

Here is the screen cast of demo which was built on top of the sliverlight application framework that I was working on for sapient labs. we will be hosting this application on the cloud (azure) shortly…

Part 1

Part 2

Expression Blend 3 Preview

2009-04-12T11:21:00.001+05:30

Looks like VS 2010 editor and the blend editor have some code base.. I was pleasantly surprised to see C# intellisense in blend, I was only expecting XAML intellisense.

Hug a Developer :)

2008-08-30T03:59:00.001+05:30

Windows 7

2008-08-17T03:28:00.001+05:30

Check this out "Engineering Windows 7" blog ... this reminds of the start of the longhorn blogs... and this is the 3rd time I am seeing the words "open and honest" in articles on Windows 7 :)

C# 3.0 for Linux

2008-08-13T20:14:00.001+05:30

This is awesome Mono implements the complete C# 3.0 spec with full support for LINQ

Add to that have a Parallel LINQ bits too...

ShaderEffect Templates & Build Tasks

2008-08-12T20:16:00.001+05:30

Checkout the ShaderEffect Build Tasks as part of WPF Futures release...

http://www.codeplex.com/wpf/Release/ProjectReleases.aspx?ReleaseId=14962

D3DImage

2008-08-12T09:18:00.003+05:30

With .NET 3.5 SP1 RTM we get a new class called D3DImage this allows for Direct3D surface to act as a Image

Checkput some of the samples that I found so far..

This is cool, check out D3DImage type sample by Dr. WPF in .NET 3.5 SP1, this opens up world of possibilities...
Also check this code shows how to map Web Cam video onto a WPF Brush using D3DImage
XNA meets WPF - by Jeremiah Morrill

Blending Modes in WPF using ShaderEffect's

2008-08-12T08:15:00.005+05:30

With the RTM of .NET 3.5 SP1 , we can now create hardware accelerated layer blending effects in WPF like those available in Image Editing tools & Photoshop & GIMP

some of the common blending modes are

Darken, Darker Colors preferred.	sampler2D input : register(s0); sampler2D tex1 : register(s1); float4 main(float2 uv : TEXCOORD) : COLOR { float4 clr1; clr1= tex2D(tex1, uv.xy); float4 Color; Color= tex2D( input , uv.xy); if (Color.r>clr1.r) Color.r=clr1.r; if (Color.g>clr1.g) Color.g=clr1.g; if (Color.b>clr1.b) Color.b=clr1.b; return Color; }
Lighten, Lighter Colors preferred.	sampler2D input : register(s0); sampler2D tex1 : register(s1); float4 main(float2 uv : TEXCOORD) : COLOR { float4 clr1; clr1= tex2D(tex1, uv.xy); float4 Color; Color= tex2D( input , uv.xy); if (Color.r<clr1.r) Color.r=clr1.r; if (Color.g<clr1.g) Color.g=clr1.g; if (Color.b<clr1.b) Color.b=clr1.b; return Color; }
Difference, Simple Arithmetic difference on color components.	sampler2D input : register(s0); sampler2D tex1 : register(s1); float4 main(float2 uv : TEXCOORD) : COLOR { float4 clr1; clr1= tex2D(tex1, uv.xy); float4 Color; Color= tex2D( input , uv.xy); Color.r=clr1.r - Color.r; Color.g=clr1.g - Color.g; Color.b=clr1.b - Color.b; return Color; }
Multiply, Simple Arithmetic Multiplication on color components.	sampler2D input : register(s0); sampler2D tex1 : register(s1); float4 main(float2 uv : TEXCOORD) : COLOR { float4 clr1; clr1= tex2D(tex1, uv.xy); float4 Color; Color= tex2D( input , uv.xy); Color.r=clr1.r * Color.r; Color.g=clr1.g * Color.g; Color.b=clr1.b * Color.b; return Color; }
NegationDifference, opposite or negative of difference	sampler2D input : register(s0); sampler2D tex1 : register(s1); float4 main(float2 uv : TEXCOORD) : COLOR { float4 clr1; clr1= tex2D(tex1, uv.xy); float4 Color; Color= tex2D( input , uv.xy); Color.r=1-(1-clr1.r - Color.r); Color.g=1-(1-clr1.g - Color.g); Color.b=1-(1-clr1.b - Color.b); return Color; }
Overlay Hardlight, Combination of Multiply for darer colors and NegationDifference for Lighter colors.	sampler2D input : register(s0); sampler2D tex1 : register(s1); float4 main(float2 uv : TEXCOORD) : COLOR { float4 clr1; clr1= tex2D(tex1, uv.xy); float4 Color; Color= tex2D( input , uv.xy); if (Color.r<0.5) Color.r=clr1.r * Color.r; else Color.r=1-((1-Color.r)(1-clr1.r)); if (Color.g<0.5) Color.g=clr1.g Color.g; else Color.g=1-((1-Color.g)(1-clr1.g)); if (Color.b<0.5) Color.b=clr1.b Color.b; else Color.b=1-((1-Color.b)*(1-clr1.b)); return Color; }
Overlay SoftLight, Variation on Overlay for Lighter colors.	sampler2D input : register(s0); sampler2D tex1 : register(s1); float4 main(float2 uv : TEXCOORD) : COLOR { float c=0; float4 clr1; clr1= tex2D(tex1, uv.xy); float4 Color; Color= tex2D( input , uv.xy); c=clr1.r * Color.r; Color.r=c+Color.r(1-((1-Color.r)(1-clr1.r)-c)); c=clr1.g * Color.g; Color.g=c+Color.g(1-((1-Color.g)(1-clr1.g)-c)); c=clr1.b * Color.b; Color.b=c+Color.b(1-((1-Color.b)(1-clr1.b)-c)); return Color; }
Exclusion	sampler2D input : register(s0); sampler2D tex1 : register(s1); float4 main(float2 uv : TEXCOORD) : COLOR { float4 clr1; clr1= tex2D(tex1, uv.xy); float4 Color; Color= tex2D( input , uv.xy); Color.r+=clr1.r-clr1.r * Color.r; Color.g+=clr1.g-clr1.g * Color.g; Color.b+=clr1.b-clr1.b * Color.b; return Color; }

Download ShaderPad and play with these effects..

New Properties in ShaderEffect Class

2008-08-12T05:55:00.001+05:30

With .NET 3.5 RTM release today, I see that there are following new properties added to the ShaderEffect class.

for setting the register index that contains the size of the image to which the effect is being applied to. documentation on web is complete with examples on this.

int DdxUvDdyUvRegisterIndex

For specifying the boundaries of the effect, this can be used to create glow like effects when so that the platform knows that the effect can determine output color outside the bounds of the UIElement. No Samples in the documentation.

double PaddingBottom
double PaddingLeft
double PaddingRight
double PaddingTop
ShaderRenderMode property on PixelShader

I shall be adding support for these in the ShaderPad shortly.

ShaderPad - WPF ShaderEffect's Workbench

2008-08-12T04:31:00.004+05:30

ShaderPad is a application like XamlPad / LinqPad , it is meant to server as WPF ShaderEffect Workbench. The ShaderEffect is a PixelShader based Effect that an be applied to any UIElement in WPF. This feature is available only in WPF 3.5 SP1

This release also includes the ability to animate the input variables that are passed to the ShaderEffect. This is a quick and dirty release :) , so expect some instability...

In next release will add the ability to load effects from a common location on web, and save to web, this allow people to more freely share their effects.

Pre Requisites
.NET 3.5 SP1 : Download.
Direct X SDK : Download June 2008.

Download the Releases and source code at CodePlex.

Lookout for Effects releases soon....

Update: Example Blending Effects here

Wave Reflection Effect New Video

2008-07-25T21:42:00.001+05:30

Added a new video to shows that this effect is not just a image effect . Original Post

Wave Reflection Shader Effect in WPF

2008-07-25T07:52:00.004+05:30

WPF 3.5 SP1 (Beta) introduces the ability to apply Pixel Shader effects to any UIElement, these will executed by GPU by compatible cards. Greg Schechter's blog is an excellent place to start learning about these features.

Shader Effects have long been used in rendering pipeline, to create great special effects. And nowadays are used by almost every game engine to enhance the visual aspects of the game play.

Another good tutorial and Check out the HLSLTester code , it is helpful in creating new effects here. I have used the Shader code from this page and added some dynamic properties to create the following effect.

Download the full code for this demo from here.

Download the compiled effect.

'The Dark Knight'

2008-07-20T05:11:00.005+05:30

Yesterday night I got to watch "The Dark Knight" and I loved it, the best part was Heath Ledger's portrayal of the Joker character.and off course the bat-pod I felt the batman character could have been portrayed a little bit more 'darker'. The dialog of the movie ...

"I'm not a monster. I'm just ahead of the curve." :)

More complete review here...

Windows Experience Index after SP1

2008-07-17T08:21:00.001+05:30

After installing Windows Vista SP1 the windows experience index shot up from 3.8 to 5.1 :) hmm..

Test Post with Windows Live Writer

2008-07-15T08:02:00.002+05:30

This is a test post using Windows Live Writer

Future of C# & C# 4.0

2008-07-13T10:10:00.006+05:30

Good discussion on Channel 9 on the future of C# and some rational behind features that might make it in C# 4.0 .(We'll see what those features are at PDC )
"Concurrency features by far are game changing aspects.." - Andres

C# 4.0: Meet the Design Team

Won a Windows Mobile!

2008-07-10T23:59:00.006+05:30

Won a BlackJack II at World Microsoft Partner Conference .

Now I have to Load Windows Mobile 6.1 on it and may be pre-beta versions of Silverlight Mobile :)

Update to SilverCarrom

2008-07-10T22:33:00.002+05:30

Fixed the Resize Bug, check out the latest version

Update to SilverCarrom

2008-07-09T23:30:00.000+05:30

Had to roll back the previous version as I had a Resizing Bug..

Update to SilverCarrom

2008-07-05T02:02:00.000+05:30

Minor update v1.1 to SilverCarrom

Increase the MaxFrameRate to 120 , this make the physics more accurate
Implemented ReSize Handlers to scale the Game fit the current Browser Size.

Getting the Required FPS in Silverlight

2008-07-04T07:18:00.000+05:30

One the first code for any game will be setup a game loop. Here are some of the posts on how to achieve this in Silverlight applications:
Creating a Game Loop - Silverlight Games 101
Tip of the Day #5: Timers and the Main Game Loop - Mike Snows Silverlight Blog
Silverlight-Speed Loop

You can see that there are two ways, one using the DispatchTimer and one using Storyboard. However I found that "The DispatcherTimer is a lower resolution timer than the timer behind the Storyboard class, which causes loss in fidelity. Additionally, the Storyboard execution is more stable across the different supported OSs and Browsers. I'll put together a sample to show the comparision." as stated in post Procedural Animation in Silverlight 2 | Adam Kinney, Continuum Explorer

So for my game I started using the empty storyboard method. But then I noticed that I getting only 60-62 FPS (frames per second) even when doing zero computations. This was causing some edge conditions manifest in collision detection like the objects passing through each other. One way to get rid of these was to increase the number of steps by increasing the FPS which I found can be by setting the EnableFrameRateCounter property to 120 in my case.
More Silverlight performance tips here.