Rule ID: SOL/250/1.0
This article describes how the Component Visibility Rule Rule works and how you can configure the rule.
The article covers the following topics:
This rule checks whether selected components are visible or hidden from a defined start component within a given distance and eye-level height. It considers obstacles and their transparency to support design objectives such as ensuring privacy, maintaining clear sightlines to exits and signage, and achieving visual separation in open or sensitive spaces.
The rule casts sightlines from each start component (viewpoint) toward the selected target components within the specified visibility radius and at the defined eye-level height. It then evaluates, using the obstacle and transparency settings, whether each target is visible or hidden, and reports any cases that do not meet the selected visibility requirement (must be visible or must be hidden).
Choose start components:
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Defines the components that act as viewpoints from which visibility is checked.
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Use filters (class, type, properties) to restrict these to relevant elements, such as entrance doors, exit doors, reception desks, key standing positions,...
Choose visibility targets:
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Defines which components the rule attempts to see/not see from each start component.
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Typical targets include doors, sanitary fixtures, signage, workstations, or any other objects whose visibility, concealment is important.
Choose obstacles:
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Defines which components are allowed to block visibility between starts and targets.
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Obstacles usually include solid or partially transparent elements such as walls, partitions, furniture, storage units, facades...; you can also set this to “Any” if all components should be considered.
All target components should be hidden
In this mode, the rule enforces visual privacy by requiring that no target components are visible from each start component.
(1) Visibility radius:
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As above, sets the 3D radius around the start component within which the rule searches for visible targets and obstacles in any direction (front, back, above, below, etc.)
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Targets outside this radius are ignored, so the rule focuses on the local context around the viewpoint.
(2) Visibility height:
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Defines the eye‑level height at which sightlines are calculated, usually representing a standing observer.
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The rule projects visibility in a horizontal plane at this height from each start component toward the targets.
Transparency threshold:
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Defines how transparent an obstacle may be before it stops blocking visibility.
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Defines how transparent an obstacle must be before it stops blocking visibility.The transparency value used for a component is the one specified in its original colour within the source model graphics. Any later modifications to transparency—such as those applied through classifications, paints, or similar features—are ignored.
If any target component within the radius is still visible from a start component after considering obstacles and transparency, the rule reports an issue, indicating that visual privacy is not satisfied.
Some target components should be visible
In this mode, the rule verifies that a minimum required number of targets remain visible from each start component, supporting safety, supervision, and way‑finding use cases.
Minimum number of visible target components:
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Specifies how many target components must be visible from each start component for the requirement to pass.
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If fewer targets are visible than this value, the rule creates an issue for that start component.
(1) Visibility radius:
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As above, sets the 3D radius around the start component within which the rule searches for visible targets and obstacles in any direction (front, back, above, below, etc.)
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Only targets inside this radius can contribute to meeting the minimum visibility requirement.
(2) Visibility height:
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As above, defines the eye‑level height at which visibility is evaluated.
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The rule counts only those targets intersected by sightlines at this height that are not blocked by obstacles.
Transparency threshold:
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As above, controls when obstacles are treated as blocking elements in the visibility calculation.
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Semi‑transparent partitions or glazing can be tuned to either block or allow visibility depending on the chosen threshold.
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Found forbidden visible components
Some target components are visible from the start component even though they should be hidden. This indicates a privacy or shielding problem.
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All target components are hidden from the start component
All targets within the visibility radius are fully blocked by obstacles, so none of them are visible from the start component.
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Less than minimum number of visible target components
In “Some target components should be visible” mode, fewer targets than the required minimum (for example 1) are visible from the start component, so the visibility requirement is not met.
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Protecting views into private spaces, such as toilets, changing rooms, or confidential areas, by making sure those targets are fully hidden from doors or circulation points.
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Ensuring that exits, refuge areas, and important signs remain visible from key locations in an accessible circulation route, in line with the principles used in other accessibility rules.
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Checking visual connections in open‑plan areas, for example verifying that reception staff can see a minimum number of doors or workstations while preventing direct views into sensitive back‑of‑house spaces.