Tutorial Screenshot Updates

When working with tutorial screenshot review or updates, consult ai/docs/screenshot-update-workflow.md.

Quick Reference

ImageComparer location: pwiz_tools/Skyline/Executables/DevTools/ImageComparer/

Diff images saved to: ai\.tmp\{Tutorial}-{Locale}-s-{Number}-diff-{PixelCount}px.png

Key shortcuts: Ctrl+S save diff, Ctrl+Alt+C copy diff, F11 next diff, F12 revert

Decisions: Accept (valid change), Revert (restore original), Fix (BUG-XXX)

Short-Form Conventions

When developer says things like:

• s-06 has an issue. look at the diff → Read diff image from ai\.tmp, analyze change
• DIA s-10 accepted → Update TODO, mark as accepted
• s-06, s-08 BUG-001 → Document bug affecting multiple screenshots

When Developer References Diff Image

Check ai\.tmp\ for recently saved diff images matching the screenshot pattern and analyze them.

Cover Shots

Cover shots (cover.png) are composite images generated by TakeCoverShot() in tutorial tests.

Key pattern: Tests override ProcessCoverShot(Bitmap bmp) to overlay images. The base calls bmp.CleanupBorder(). On Win11, CleanupBorder() returns a new Bitmap — overrides MUST capture and return base.ProcessCoverShot(bmp), not the original bmp.

Tests with overrides: DdaTutorialTest, DiaUmpireTutorialTest, DiaSearchTutorialTest, AcquisitionComparisonTutorialTest, ExistingExperimentsTutorialTest.

Key files: TestUtil/TestFunctional.cs (ProcessCoverShot, TakeCoverShot), TestUtil/ScreenshotManager.cs (TakeShot).

See ai/docs/screenshot-update-workflow.md § "Cover Shot System" for full details.

Win11 Machine Setup

For consistent screenshots on Windows 11:

• Transparency effects: OFF (Settings > Personalization > Colors) — prevents desktop color bleeding into titlebar
• Display scaling: 100% (96 DPI) — corner radii scale with DPI
• Choose your mode: Light

Win11 Corner Rendering

ScreenshotProcessingExtensions.CleanupBorder11() redraws rounded corners on a white background. Uses GraphicsPath.AddArc with 8px radius (forms) or 4px (tool windows). A CONSIDER comment in the code notes that Gdi32.CreateRoundRectRgn() exists as a potential alternative but produced no meaningful visual difference when tested.