Display Topology Switching

RigSwitch controls your monitors through low-level Windows Connecting and Configuring Displays (CCD) Win32 driver APIs rather than generic display emulation.

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Why Win32 CCD?

Standard multi-monitor tools often rely on virtual display drivers or Windows shell shortcuts (Win + P). These approaches suffer from severe drawbacks:

• Windows continues treating disabled screens as connected video sinks, allowing windows and mouse pointers to vanish off-screen.
• DirectX and Vulkan games often query the GPU adapter and launch on the inactive monitor.
• Virtual display drivers introduce display latency and require test-signing or kernel-mode driver certificates.

RigSwitch invokes QueryDisplayConfig and SetDisplayConfig directly:

1. Enumerates all active and inactive path descriptors on the GPU adapter.
2. Identifies target and inactive monitors using their hardware EDID, monitor name, or Windows display path.
3. Sets DISPLAYCONFIG_PATH_ACTIVE on the target display while explicitly stripping the flag from the inactive screen.
4. Commits the changes atomically using SDC_APPLY | SDC_SAVE_TO_DATABASE | SDC_ALLOW_CHANGES.

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Fail-Safe Safety Gates

Changing display topology carries an inherent risk of a black-screen lockout if the target monitor is turned off, unplugged, or entering a deep power-saving sleep state.

RigSwitch eliminates this risk using a multi-step Display Reachability Gate:

[Profile Switch Requested]
            │
            ▼
[QueryDisplayConfig (QDC_ALL_PATHS)]
            │
            ├─► Is Target Monitor physically reachable?
            │         │
            │         ├─► NO  ──► [ABORT SWITCH & ALERT USER]
            │         │           Current display remains 100% active.
            │         ▼
            │        YES
            ▼
[Apply SDC_APPLY Atomically]

If the target display cannot be reached:

• The current active display is never disabled.
• The switch halts immediately.
• A Windows balloon notification alerts you: "Target display [Name] is disconnected or powered off."