There are many possibilities to store user data inside a Nova Scene. That's why I've just added a new sample on Nova Wiki.

If you are interested, just have a look here.

Sometimes, it may be useful to create a kind of panel perpendicular to the active camera. That's why, I've added a new page to demonstrate it on our wiki. 

Enjoy!

Maybe you wonder why it may be useful to run on CLR 4.0?

Well, I will say mainly for many Microsoft .NET Framework 4.0 news. As an example (it’s not the only one), if you want to use Windows Communication Foundation 4.0 in Nova Studio Plugins.

If you want to know more about this tip, just go to our wiki.

Class Script

    Private slider As NovaSlider
    Private currentScene As NovaScene 
    
    Public Sub New(scene As NovaScene)
        currentScene = scene
        slider = Scene.CreateSlider()

        slider.Top = 10
        slider.Left = 10

        slider.Min = 0.0
        slider.Max = 3.0
        slider.Value = slider.Max
        slider.Width = 300
        slider.ID = "SliderQualitySensor"
        slider.Text = "Quality Sensor"
        slider.RelativeWidth = False
        slider.Visible = True
        
        AddHandler slider.ValueChanged, AddressOf manageValueChanged
    End Sub

    Private Sub manageValueChanged(ByVal o As Object, e As EventArgs)
        If  slider.Value >= 0.0 AndAlso slider.Value < 1.0 Then
            changeToLowQuality()                
        ElseIf  slider.Value >= 1.0 AndAlso slider.Value < 2.0 Then
            changeToMediumQuality()
        Else
            changeToHighQuality()
        End If
    End Sub
    
    Private Sub changeToLowQuality()
        currentScene.Engine.QualityLevel = 0
        NovaEngine.Shadows = False
                
        NovaEngine.BumpChannel = False
        NovaEngine.SpecularChannel = False
        NovaEngine.ReflectionChannel = False
        NovaEngine.RefractionChannel = False
        Novaengine.EmissiveChannel = False
        Novaengine.AmbientChannel = False 
        NovaEngine.ParticleSystems = False
        NovaEngine.MirrorMatrixActivated = False
    End Sub
    
    Private Sub changeToMediumQuality()
        currentScene.Engine.QualityLevel = 1
        NovaEngine.Shadows = False
                
        NovaEngine.BumpChannel = True
        NovaEngine.SpecularChannel = True
        NovaEngine.ReflectionChannel = True
        NovaEngine.RefractionChannel = False
        Novaengine.EmissiveChannel = False
        Novaengine.AmbientChannel = False 
        NovaEngine.ParticleSystems = True
        NovaEngine.MirrorMatrixActivated = False
    End Sub
    
    Private Sub changeToHighQuality()
        currentScene.Engine.QualityLevel = 3
        NovaEngine.Shadows = True

        NovaEngine.BumpChannel = True
        NovaEngine.SpecularChannel = True
        NovaEngine.ReflectionChannel = True
        NovaEngine.RefractionChannel = True
        Novaengine.EmissiveChannel = True
        Novaengine.AmbientChannel = True 
        NovaEngine.ParticleSystems = True
        NovaEngine.MirrorMatrixActivated = True
    End Sub
    
    Protected Overrides Sub Finalize()
        RemoveHandler slider.ValueChanged, AddressOf manageValueChanged
        currentScene.Widgets.Clear()
    End Sub
End Class

SliderManager.nsr (2.83 kb)

I've just published a new tip on Vertice wiki. It will allow you change the active novaCamera on the fly using a joystick.

Do you know also you can publish on our wiki? So don't hesitate to contact me if you need further informations and if you think it's too difficult, you should know that everyone has talent, it's my leitmotiv! 

If you are a little bit afraid about publishing, I will help you on your first article by an author-reader cycle, so join us in the Vertice community!

  Private myScene As NovaScene
    Private epsilon As Single = 0.0001
    Private cameraLastGlobalPosition As Vector3
    Private cameraLastRotationPosition As Vector3
    Private camera As NovaCamera
    
    Public Sub New(ByVal scene As NovaScene)
        myScene = scene
        
        camera = myScene.GetCamera("MainCamera")
        StoreCameraPostion()

        AddHandler myScene.AfterRender, AddressOf manageAfterRender
    End Sub

    Private Sub manageAfterRender
        If Math.Abs(CType((camera.GlobalPosition - cameraLastGlobalPosition).Length, Single)) 
> epsilon OrElse Math.Abs(CType((camera.Rotation - cameraLastRotationPosition).Length, Single)) 
> epsilon Then    
            StoreCameraPostion()
            
            PluginHelper.LogInfo("it moves!")
        End If
    End Sub

    Public Sub StoreCameraPostion()
        cameraLastGlobalPosition = camera.GlobalPosition
        cameraLastRotationPosition = camera.Rotation 
    End Sub

    Protected Overrides Sub Finalize()
        RemoveHandler myScene.AfterRender, AddressOf ManageAfterRender
    End Sub
End Class 

I've just published a new tip on our new wiki documentation that will allow you to extend Nova Studio Scripts.

I think, this tip will be very useful to all developers that use Nova scripting model. 

Enjoy!

In my last post on this subject, I suggested that deploying MySQL ODBC drivers on client PC was not a good design. I spoke about Service Oriented Architecture or more specifically about Rest Services. There will be so many things to write about SOA and Rest Services but it's not the subject. I will just technically describe how I created a Rest service that returns records from my MySql Database.

First of all a small architecture picture:

In my sample, a Web Site on IIS is exposing REST Services over HTTP. These services expose data from my database called "bCatalog" and specifically from my table tProducts. The return data are xml formatted, more specifically in an atom format. Data may be accessed through specific urls such as:

• "http://localhost:2522/ProductService.svc/tproducts: get all records from the table "tProducts". I highlighted the important tags in resulting xml document:

• "http://localhost:2522/ProductService.svc/tproducts('Box01WithLabel')": get the specific product from de table "tProducts" where "objectID" (the primary key) is equal to "Box01WithLabel".

In the solution you can download (at the end of the post), you will see I used two Microsoft technologies: ADO.NET Data Services to create Rest Services and ADO.NET Entity Framework to request data from my sql database. Moreover, this time I used the managed MySql driver you can download here.

The next step was to update my Nova Script in VB.NET to request data on http. So I just proceeded as follow:

• I replaced my database Connection String by a simple URL to request all data from "tProducts" table.
• I completely rewrote the existing "LoadObjectsFromDatabase" method to take into account an http query. Technically, the .NET Framework offers all you need to make http requests and to interpret resulting XML data. The class to use to request is "HttpWebRequest" and the class to use to manipulate XML is "XmlDocument":

The harder task was to manipulate the atom XML Document. I lost a couple of minutes thinking why my xpath request (to get all entry tags, i.e. database records) didn't return anything. In fact, it was quite simple! Indeed, in atom format, there are default namespaces that must prefix all tags. The rest of the job was just finding nodes, route nodes and gatting and storage of values (database fields).

So, with this solution, my database is no more directly exposed to the web and especially I have not to deploy MySql ODBC drivers on each client. In the following zip, you will find:

• the mxb file I used,
• the corresponding nss file,
• the nsr file that contains the previous scripting in case,
• MySql database scripting.
• the web exposing Rest Services (you will need Visual Studio 2008 SP1 to load the project)

VerticeSample-Last.zip (66.48 kb)

Enjoy!

Let me know if you are interested with the code to load data only on user interaction (with cache store) by leaving me a comment for this post. Moreover if you have any questions about SOA, please contact me.

It's now time to analyze the solution. We do not yet know very well (joke), but when I see a code or an architecture, I used to have a critical eye over. I confess that it is the same for the code I produce. So, here are my thoughts about the developed solution:

• Deploying MySQL ODBC driver may be acceptable for an small intranet solution but is not acceptable for a full web compliant environment.
• The direct use of a database from a Web Plugin may be dangerous for the database server since it forces administrators to openthe firewall for a specific port. That's unsecure and it's not the state of the art even if we place the database server in a DMZ. So we should use secured Web Services or Rest Services, i.e. on a standard protocol (http or https). this is what is called a Service-Oriented Architecture (SOA).
• It will be better to only store the url of the services layer on http instead of a connection string. Url that can be set by the http server that manages the Web Page including the web plugin tag object.
• I use the root account to access the catalog that I use to store my information. It's dangerous from a security point of view. We should use a dedicated account with less privileges.
• You'll notice in my script, I hard stored the culture to format the price. On the other hand, we should not make this as a dynamic part since in my database I store Euros and not Dollars. And with the price of the dollar right now, it won't be interesting, except if we manage changes according to the user culture.
• If you take a look at the database schema, you will notice it is simplistic. Indeed, products may have more data such as categories, keywords, etc. and we should use an integer as a primary key to perform powerful tables joins.
• The last thing is the way to load once all data from database. What happens if data change in the database after web Plugin loading? Well, nothing in fact because data are not collected when the user interaction is executed.
• Last but not least, the Web Plugin had to be updated to reference the missing "System.Data.dll" assembly to access "System.Data.Odbc" namespace. This update will be available soon with Nova Explorer auto-update.

Well, you are going to tell me that I coded with my feets ;-). In fact I responded directly to a need that I have been asked for. Moreover, any script may always be improved with time. I develop this solution in a couple of hours (in fact 3 hours). This partly explains it... Now I will attach myself to do things in the rules of art, anyway, as I believe they should be :-)

So in my next post I will show you how to develop a REST Architecture to expose my data and to consume it in a Nova script.

See you soon!

Well, last but not least post on this topic, let's use this scene with differents clients.

• Nova Explorer, certainly the most used:

• A specific Windows Form application that use the .NET Web Player control:

• The Web Plugin inside Internet Explorer:

The first step is to generate the mxc and the html files by using Nova Explorer Publish menu:

Then, you have just to open the generated Html page:

Just one more thing like will say a friend of mine: since the trust does not exclude some form of control, below here are of the database contents I used.

In my next post, I will talk about architecture and specifically the one that is induced by this complete sample. In other terms, I will talk about its pros and cons.