MCP: add viewer.* namespace (camera, screenshots, input events)#5980
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… MRUiMcp.cpp Prep for viewer.* namespace: the existing MRViewerMcp.cpp hosts ui.* tools, rename to MRUiMcp.cpp so the new viewer.* TU can take the old name. resolveId is about to get a second caller (viewer.fit), so lift it and idOf to a shared MRMcpCommon.h/.cpp.
- viewer.fit takes optional objectIds and/or 3D points and unions their boxes; falls back to whole-scene fitData when neither is given. - viewer.setupCamera takes mandatory forwardDir + upDir, orthogonalizes upDir against forwardDir, and always refits after reorientation.
One tool, two modes: default captures just the 3D viewport via the sync captureSceneScreenShot path; `includeUi: true` captures the whole window via captureUIScreenShot, blocking on a promise until the async callback fires on the next frame. Dual output: `filePath` -> write server-side and return the path; omitted -> return inline base64 PNG bytes.
preciseFitDataToScreenBorder / preciseFitBoxToScreenBorder give exact framing to the viewport edges. Both default to snapView=false, so the camera angle is preserved — setupCamera's direction is no longer silently snapped to canonical. Drops the snapView tool param entirely.
Unified per-domain event injection. `sendMouseEvent` dispatches on `type` (down/up/click/move/scroll); `click` = down+up with an optional pre-hover move. `sendKeyboardEvent` takes a string key — single printable char or a named key like `Escape` / `ArrowUp` / `F5`. Modifiers are string arrays (`["ctrl","shift"]`). All events go through Viewer::emplaceEvent (the same path Python UI tests use) with skipFramesAfterInput between steps to give plugins a frame to react.
Fedr
approved these changes
Apr 24, 2026
oitel
approved these changes
Apr 24, 2026
…creenshots # Conflicts: # source/MRViewer/MRViewerMcp.cpp
This was referenced Apr 27, 2026
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Summary
Adds the
viewer.*MCP namespace: camera control, screenshots, and input-event injection. Extends issue MeshInspector/MeshInspectorCode#7205.New tools:
viewer.fit— frame objects/points/whole scene (usespreciseFit*ToScreenBorder, preserves camera angle)viewer.setupCamera— set camera forward/up direction; auto-orthogonalizes upDir via Gram-Schmidtviewer.captureScreenshot— 3D viewport (sync) or whole window (async, blocks on promise/future); dual output mode (server-sidefilePathor inline base64 bytes)viewer.sendMouseEvent— unified mouse injection (down/up/click/move/scroll)viewer.sendKeyboardEvent— unified keyboard injection (down/up/press/repeat); string key names (\"a\",\"Escape\",\"F5\",\"ArrowUp\"); modifiers as string arrayAlso extracts
resolveId/idOffromMRSceneMcp.cppinto a sharedMRMcpCommon.h/.cppnow that a second caller (viewer.fit) needs them, and renames the existingMRViewerMcp.cpp(which hostsui.*) toMRUiMcp.cppso the new viewer-namespace TU can take the clearer name.Commits
resolveId/idOfintoMRMcpCommon.h/.cpp; renameMRViewerMcp.cpp→MRUiMcp.cpp.viewer.fit+viewer.setupCamera.viewer.captureScreenshot.preciseFit*ToScreenBorder; drop thesnapViewparam (always false now).viewer.sendMouseEvent+viewer.sendKeyboardEvent— all events go throughViewer::emplaceEvent(same pattern astest_ui/scenarios/scenario_helpers.py), withskipFramesAfterInputbetween steps.Test plan
All 6 tools verified live via MCP:
viewer.captureScreenshotfile-mode → PNG on disk with89 50 4E 47magicviewer.captureScreenshotbytes-mode at custom resolution → base64 PNGviewer.captureScreenshotwithincludeUi: true→ full window including ribbon/scene tree/panels (async promise path)viewer.setupCameratop/left/isometric (forwardDir=[-1,-1,-1]) directions — camera angle preserved, navigation cube matchesviewer.setupCamerarejects zeroforwardDirandupDirparallel toforwardDirwith typed errorsviewer.fitwhole-scene, per-object, per-point, mixed — all frame correctly; unknown object id → typed errorviewer.sendMouseEventtype=scroll → view zoom changed; error paths (unknown type, missing button fordown, missingscrollDeltaforscroll, unknown modifier)viewer.sendKeyboardEventCtrl+Z → undoes last scene mutation; unknown key name → typed error🤖 Generated with Claude Code