Update scaling math to land on 100% consistently.

[hipsterusername]

Summary

This pull request updates the zooming functionality in the CanvasStageModule to improve user experience by refining the scale factor and introducing snapping to common zoom levels. The changes ensure smoother scaling and better precision when zooming in and out.

Zooming Improvements:

• Refined Scale Factor: Updated the SCALE_FACTOR in the DEFAULT_CONFIG from 0.999 to 0.9995 for finer zoom adjustments. (invokeai/frontend/web/src/features/controlLayers/konva/CanvasStageModule.ts, invokeai/frontend/web/src/features/controlLayers/konva/CanvasStageModule.tsL34-R34)
• Enhanced Scale Constraining: Modified the constrainScale method to:
  • Round the scale to two decimal places to address floating-point precision issues.
  • Snap the scale to 1.0 (100%) with a tolerance of 0.05 for a better user experience.
  • Introduce snapping to other common zoom levels (e.g., 0.25, 0.5, 0.75, 1.5, 2, etc.) with a tolerance of 0.03. (invokeai/frontend/web/src/features/controlLayers/konva/CanvasStageModule.ts, invokeai/frontend/web/src/features/controlLayers/konva/CanvasStageModule.tsL233-R250)

Related Issues / Discussions

Some miscellaneous discord discussions.

QA Instructions

Scroll around on the canvas.

Merge Plan

Should be good to go on review.

Checklist

• The PR has a short but descriptive title, suitable for a changelog
• Tests added / updated (if applicable)
• Documentation added / updated (if applicable)
• Updated What's New copy (if doing a release after this PR)

[psychedelicious]

Good idea!

[ufuksarp]

Thank you.