Configuring distance-based texture downscaling

Distance-based texture downscaling is a performance improvement technique where the displayed quality of textures (images) on the outside of multipatch features is automatically adjusted based on the distance of the feature to the camera.

Texture downscaling is a display property and does not impact the source data. This method is only available in ArcGlobe.

The process of texture downscaling is not a seamless, or continuous, scaling of the texture imagery but, rather, is applied in three distinct zones. For example, the zones include a full-resolution band and two downscaled resolution bands. The viewing distance from the camera to the feature will determine which texture resolution is displayed on the screen.

The image here depicts a 3D view using distance-based texture downscaling.

The configurable factors

There are two configurable factors involved with distance-based texture downscaling:

Configurable element	Description
The view distance at which texture downscaling is applied	This value is in meters and is the direct 3D distance from the camera object (observer position) to the 3D placement (target) location of the multipatch. For building features, this distance is represented as a virtual sphere around the 3D object. See Understanding the observer and target for more information.
The amount of downscaling to apply	Texture resolution adjusts both the width and height of the image by half for each drop in resolution, resulting in a texture that is one-quarter of the previous resolution. For example, a 1,000 x 1,000 (1,000,000 pixel) texture image would be reduced to a 500 x 500 (250,000 pixel) texture image when downscaled one level. There are five texture reductions available, from Low (1/4) to Extreme (1/1024).

The image below is an example of reducing the multipatch texture resolution for a layer starting from no downscaling through to extreme.

Considerations

By default, texture downscaling is enabled for all multipatch layers, and the settings are designed to work well with relatively small objects with many textures, such as buildings or 3D models. Here are some reasons why other settings may be more appropriate:

• Your textured data is low quality and texture downscaling is not required.
• You have optimized hardware and can increase the texture quality display without losing performance.
• Your textured data includes geographically large features so the default downscaling distances of 250 meters and 1,000 meters are too small. For example, a seismic image pasted onto a 5-kilometer-wide frame would be better defined with much larger downscaling distances.

Whether you choose to disable or change the settings for automatic distance-based texture downscaling, it does not invalidate the cache for the layer.

Steps to disable distance-based texture downscaling

Follow the steps below to disable distance-based texture downscaling for a multipatch feature class layer:

Steps:

1. Right-click the multipatch layer in the table of contents and click Properties.
The Layer Properties dialog box appears.
2. Click the Globe Display tab and go to the Rendering section.
3. Click Advanced.
The Texture Downscaling Properties box appears.
4. Check Disable texture downscaling and click OK.
5. Click OK to close the Layer Properties dialog box.

   The layer now always displays the highest texture resolution.

Steps to configure the two factors of distance-based downscaling

Repeat steps 1–3 from above, then follow the steps below to configure the two factors of distance-based texture downscaling for a multipatch feature class layer using the Texture Downscaling Properties dialog box.

Steps:

1. Set Distance to begin downscaling (in meters) for Level 1.
2. Choose a value for Downscaling factor for Level 1. You can choose from the following:
   • Low (1/4)
   • Medium (1/16)
   • High (1/64)
   • Very High (1/256)
   • Extreme (1/1024)
3. Set Distance to begin downscaling (in meters) for Level 2.
4. Choose a value for Downscaling factor for Level 2.
5. Click OK.
6. Click OK to close the Texture Downscaling Properties dialog box.

   The layer now adjusts the texture resolution using the updated distances and downscaling factors.

Tip:

You can also lower the highest resolution of your textures by adjusting the Material texture resolution slider on the Globe Display tab of the Layer Properties dialog box. The use of distance-based texture downscaling will operate as an additional factor to this base setting. See Downscaling textures for a multipatch layer.