When Clusters are created in PADS4 CTRL Center, system-defined Viewer Variables are automatically available. These variables help control content distribution across Clustered Viewers based on their position and availability.

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System-Defined Cluster Viewer Variables

VariableDescription
ClusterWidthTotal number of horizontal Viewers in the Cluster.
ClusterHeightTotal number of vertical Viewers in the Cluster.
HorizontalPositionDefines the current page number that should be displayed based on viewer availability in a horizontally aligned Cluster. Adjusts dynamically when Viewers go offline.
VerticalPositionDefines the current page number that should be displayed based on viewer availability in a vertically aligned Cluster. Adjusts dynamically when Viewers go offline.
IndexXThe designed horizontal position of this Viewer within the Cluster.
IndexYThe designed vertical position of this Viewer within the Cluster.

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Example Cluster Configuration

The example below illustrates a 2x2 Cluster with 4 Viewers.
Cluster ViewersHorizontal PositionVertical PositionIndexXIndexY
Cluster Viewer 11100
Cluster Viewer 22310
Cluster Viewer 33201
Cluster Viewer 44411

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How These Variables Work in a Cluster

  1. Dynamic Page Assignment:
    • If Viewer 2 goes offline, Viewer 3 or Viewer 4 will automatically take over its content.
    • If a Viewer is removed or disabled, PADS4 automatically reassigns the correct page positions.
  2. Intelligent Content Distribution:
    • HorizontalPosition ensures content is evenly distributed when a Viewer is removed.
    • VerticalPosition helps determine which upper Viewers’ content moves down if a screen fails.
  3. Flexible Layout Customization:
    • IndexX/IndexY allow precise control over the placement of Viewers within a Cluster.
    • Adjustments can be rule-based, ensuring smooth failover handling.

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Practical Use Cases

  • Airport Flight Information Displays: Ensures continuous flight listings across multiple screens.
  • Menu Boards in Restaurants: Automatically shifts menu content if one screen fails.
  • Retail Digital Signage: Prevents content gaps and adjusts layout dynamically.
By utilizing these Cluster Viewer Variables, you can optimize digital signage layouts, reduce downtime, and automate content distribution across your PADS4 system.