# How to: Transform the Scale of a 3-D Model

This example shows how to scale a 3-D object. To scale a 3-D object, use a ScaleTransform3D. The ScaleX, ScaleY, and ScaleZ properties resize the element by the factor you specify. For example, a ScaleX value of 1.5 stretches an object to 150 percent of its original width. A ScaleY value of 0.5 shrinks the height of an object by 50 percent. The code below shows using a ScaleTransform3D as the transform for a GeometryModel3D.

<!-- Apply a scale transform to the object. You can transform the scale of the object
for the X, Y, or Z axis. The ScaleX, ScaleY, and ScaleZ properties resize the object
by the factor you specify. For example, a ScaleX value of 1.5 stretches the object to
150 percent of its original width. A ScaleY value of 0.5 shrinks the height of an object
by 50 percent. -->
<GeometryModel3D.Transform>

<!-- This Scale Transform stretches the object horizontally by 200 percent and shrinks it
vertically by 50 percent. -->
<ScaleTransform3D ScaleX="2" ScaleY="0.5" ScaleZ="1" CenterX="0" CenterY="0" CenterZ="0" />
</GeometryModel3D.Transform>


## Example

The following code shows the entire sample.

<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" >
<DockPanel>
<Viewbox>
<Canvas Width="321" Height="201">

<!-- The Viewport3D provides a rendering surface for 3-D visual content. -->
<Viewport3D ClipToBounds="True" Width="150" Height="150" Canvas.Left="0" Canvas.Top="10">

<!-- Defines the camera used to view the 3D object. -->
<Viewport3D.Camera>
<PerspectiveCamera Position="0,0,2" LookDirection="0,0,-1" FieldOfView="60" />
</Viewport3D.Camera>

<!-- The ModelVisual3D children contain the 3D models -->
<Viewport3D.Children>

<!-- This ModelVisual3D defines the light cast in the scene. Without light, the 3D
object cannot be seen. Also, the direction of the lights affect shadowing. If desired,
you can create multiple lights with different colors that shine from different directions. -->
<ModelVisual3D>
<ModelVisual3D.Content>
<DirectionalLight Color="#FFFFFF" Direction="-0.612372,-0.5,-0.612372" />
</ModelVisual3D.Content>
</ModelVisual3D>
<ModelVisual3D>
<ModelVisual3D.Content>
<GeometryModel3D>

<!-- The geometry specifies the shape of the 3D plane. In this sample, a flat sheet is created. -->
<GeometryModel3D.Geometry>
<MeshGeometry3D
TriangleIndices="0,1,2 3,4,5 "
Normals="0,0,1 0,0,1 0,0,1 0,0,1 0,0,1 0,0,1 "
TextureCoordinates="0,0 1,0 1,1 1,1 0,1 0,0 "
Positions="-0.5,-0.5,0.5 0.5,-0.5,0.5 0.5,0.5,0.5 0.5,0.5,0.5 -0.5,0.5,0.5 -0.5,-0.5,0.5 " />
</GeometryModel3D.Geometry>

<!-- The material specifies the material applied to the 3D object. In this sample a linear gradient
covers the surface of the 3D object.-->
<GeometryModel3D.Material>
<MaterialGroup>
<DiffuseMaterial>
<DiffuseMaterial.Brush>
<LinearGradientBrush StartPoint="0,0.5" EndPoint="1,0.5">
<LinearGradientBrush.GradientStops>
<GradientStop Color="Yellow" Offset="0" />
<GradientStop Color="Red" Offset="0.25" />
<GradientStop Color="Blue" Offset="0.75" />
<GradientStop Color="LimeGreen" Offset="1" />
</LinearGradientBrush.GradientStops>
</LinearGradientBrush>
</DiffuseMaterial.Brush>
</DiffuseMaterial>
</MaterialGroup>
</GeometryModel3D.Material>
<!-- Apply a scale transform to the object. You can transform the scale of the object
for the X, Y, or Z axis. The ScaleX, ScaleY, and ScaleZ properties resize the object
by the factor you specify. For example, a ScaleX value of 1.5 stretches the object to
150 percent of its original width. A ScaleY value of 0.5 shrinks the height of an object
by 50 percent. -->
<GeometryModel3D.Transform>

<!-- This Scale Transform stretches the object horizontally by 200 percent and shrinks it
vertically by 50 percent. -->
<ScaleTransform3D ScaleX="2" ScaleY="0.5" ScaleZ="1" CenterX="0" CenterY="0" CenterZ="0" />
</GeometryModel3D.Transform>
</GeometryModel3D>
</ModelVisual3D.Content>
</ModelVisual3D>
</Viewport3D.Children>

</Viewport3D>
</Canvas>
</Viewbox>
</DockPanel>
</Page>