Promote auto-zoom to production: configurable intensity, sensitivity, and dead zone by bytemines · Pull Request #1646 · CapSoftware/Cap

bytemines · 2026-03-05T14:36:30Z

newshowcase.mp4

Context

Auto-zoom has existed since PR #558 (Aug 2025) and was refined in
#1090 and #1106, but it remained experimental and hard to discover.
Users have been asking for it (issues #352, #758) — some citing it
as the reason they'd switch from Screen Studio or FocuSee to Cap.

The feature was gated behind:

custom_cursor_capture2 experimental setting (must enable first)
DEV-only context menu (generate button hidden in production)
No user-facing controls for zoom amount or sensitivity

This PR makes auto-zoom accessible, configurable, and production-ready.

Changes

Recording setup

Add "Auto Zoom" toggle in Studio Mode recording controls
Remove the toggle from experimental settings (moved to main UI)
Increase main window height to fit the new control

Editor

Remove DEV guard from "Generate zoom segments from clicks" context menu
Remove custom_cursor_capture2 gate from Auto zoom mode tab
Add Auto Zoom section in sidebar with Generate/Remove buttons
Add zoom intensity slider (1.0–3.0x, was hardcoded 1.5x)
Add sensitivity slider (0.0–1.0, controls how many segments are generated)
Add "Remove all zoom segments" to zoom track context menu
Clear zoom selection state when removing all segments
Centralize zoom actions in shared projectActions

Zoom algorithm

Remove movement-based zoom triggering — zoom now triggers only on clicks, matching industry standard (Screen Studio, ScreenArc, FocuSee)
Cursor movement still drives the focal point during active zoom segments
Filter cursor events to trimmed time ranges when generating zoom segments
Remap event timestamps from recording-time to timeline-time for trimmed videos
Guard against zero/NaN timescale in remap math
Validate input parameters (clamp zoom amount, sensitivity)

Rendering

Add dead_zone_radius to ScreenMovementSpring (default 0.03)
Suppress micro-jitter in spring focus interpolation during zoom playback
Use squared distance comparison instead of sqrt in hot loop
Old project files without this field load correctly via serde defaults

Backend

Add auto_zoom_amount and auto_zoom_sensitivity to GeneralSettingsStore
Pass configurable settings through to segment generation algorithm
Sensitivity scales click grouping thresholds
Avoid unnecessary clone of project config when reading timeline segments

What we did NOT change

Rendering pipeline (spring physics, viewport interpolation)
Cursor capture pipeline (custom_cursor_capture2 still experimental)
ZoomSegment struct, ZoomMode enum

Closes #758

… and dead zone Add "Auto Zoom" toggle to Studio Mode recording setup, replacing the experimental settings toggle. Add zoom intensity and sensitivity sliders in the editor sidebar with generate/remove controls. Add dead zone radius to spring focus interpolation to suppress viewport jitter. Increase main window height to fit the new control.

apps/desktop/src-tauri/src/lib.rs

apps/desktop/src-tauri/src/recording.rs

crates/rendering/src/zoom_focus_interpolation.rs

crates/project/src/configuration.rs

apps/desktop/src/routes/(window-chrome)/new-main/index.tsx

…t fix - Propagate GeneralSettingsStore::get errors instead of swallowing them - Clamp base_zoom_amount and sensitivity before threshold math - Compare squared distance instead of computing sqrt every sample - Fix dead_zone_zero test to verify actual cursor tracking behavior

- Use Self::default_dead_zone_radius() in Default impl instead of hardcoded 0.03 - Change cursor-default to cursor-pointer on auto-zoom toggle button

Auto-zoom now triggers exclusively on click events, matching the industry standard (Screen Studio, ScreenArc, FocuSee). Cursor movement data is still used to determine zoom focal point during active segments, but no longer independently creates zoom intervals.

apps/desktop/src/routes/editor/context.ts

Auto-zoom now filters cursor events to trimmed time ranges and remaps timestamps to timeline-time before generating segments. Previously it used the full raw recording duration and all events.

apps/desktop/src-tauri/src/lib.rs

apps/desktop/src-tauri/src/recording.rs

- Guard against zero/NaN/negative timescale in remap logic - Borrow project_config instead of cloning - Clear zoom selection when removing all zoom segments

crates/rendering/src/zoom_focus_interpolation.rs

0xFloyd · 2026-03-06T01:36:21Z

anything blocking this from being merged? @richiemcilroy happy to do whatever to push this over the line