Shader type in VB.NET

Encoder QR Code in VB.NET Shader type

(Unused in Silverlight)

The member names for the individual floats depend on their usage. For example, a color has the properties r, g, b, and a. HLSL is interesting in that it can perform multiplication and other operations on whole structures. In that way, the number of instructions is reduced, but it can be hard to understand when you first look at it. For example, the exmple multiplies together two float4 values.

With the shader compiled and the wrapper class in place, it s time to try the shader in your own application. Like any other element used in XAML, you must either include an implicit namespace in your application settings or map a namespace in the XAML file. In this case, because the shader is in the project with the XAML, you ll use an explicit map in the XAML. Listing 18.28 shows the effect of using the shader with a red tint. It ll look gray in print, but you can tell there s a tint over the whole image.

Result:

Code:

<UserControl x:Class="SilverlightApplication61.MainPage" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:local="clr-namespace:SilverlightApplication61" mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="400"> <Grid x:Name="LayoutRoot"> <Grid Background="White" Width="180" Margin="25"> <StackPanel x:Name="Elements" Margin="10"> <TextBlock Text="Hello World" Margin="10" /> <TextBox Text="This is a textbox" Margin="10" /> <Button x:Name="Button" Content="Button" Margin="10" /> </StackPanel> <Grid.Effect> <local:ShaderEffect1 ColorFilter="Red" /> </Grid.Effect> </Grid> </Grid> </UserControl>

This is the same example used in previous sections, but instead of a drop-shadow, it uses the pixel shader with a parameter of Red for the ColorFilter property B. The end result is an angry red form. As was the case in the other examples, the use of a pixel shader has reverted the text back to grayscale font smoothing. Pixel shaders are a great way to provide your own custom effects or to use effects developed by others. Learning HLSL can be difficult at times, but the payoff is worth it: you can use pixel shaders in Silverlight, in WPF, and, of course, in DirectX and XNA. Pixel shaders, even the software-rendered ones in Silverlight, are extremely efficient as well. When considering pixel-manipulation strategies in an application, the creation of a pixel shader should be high on your list of options.

18.5 Summary

Silverlight s inherent graphical capabilities go far beyond cartoons and visual fireworks. By shaping these elements into illustrations, graphics can provide a bridge to your users to help them connect with difficult concepts. These valuable illustrations can be composed of a series of shapes compiled from arcs, curves, and lines. These shapes can then be filled with gradient colors or textured visuals such as images and videos. Effects augment both graphics and controls. The use of a subtle drop shadow or a blur can help users focus their attention on a specific part of the screen. If those effects aren t sufficient, you also have the option to create your own effects in the form of pixel shaders.

Summary

Vector graphics and effects are definitely some of the strong points in Silverlight. Previous technologies had no equivalents; you had to write everything from scratch or use primitive drawing options. Silverlight also has rich support for images and media, another of its strong points. We ll discuss that in chapters 20 and 21. Before we get there, let s put our newfound vector graphics skills to use on that oldest of modern media: paper.

An overview of the printing API How to print onscreen content How to scale content for print Getting data from a service for a report Creating headers, footers, and more

Silverlight 4 is the first release that can be considered truly ready for business. The support for binding and validation, WCF RIA Services, and out-of-browser trusted applications are all major factors in this. One equally important reason is the added support for printing. Many business applications need to print paper forms and reports as a standard part of their process. Very large-scale applications typically farm that functionality out to a server somewhere with centralized print systems. Most other applications use printers directly mapped and available on the client workstation. For those applications, platform support for printing is essential. Printing support opens up other nonbusiness scenarios as well. Now you can make that coloring-book creator or recipe application you ve had in your cool app ideas folder. I joke about printing, but I used to print directions before I had a GPS,