README

SkiaGalleryFlow

A Card Stack / Coverflow control prototype for Delphi FMX. Built entirely on Skia4Delphi.

SkiaGalleryFlow (Async Coverflow v0.1)

Features:

[ Async Loading Pipeline ]

• Background Image Decoding : Loads files off the main UI thread.
• Offscreen Thumbnail Raster : Pre-scales to target size via TSkSurface.
• Thread-Safe Sync : Safely injects ISkImage back into the UI.
• Anti-Duplicate Locking : State flags prevent double-loading.
• Smart Proximity Loader : Spawns threads only for visible items.

[ Rendering Pipeline ]

• Cached Skia Objects : Reuses ISkPaint to prevent memory overhead.
• Painter's Algorithm (Z-Order): Sorts slides by offset for correct overlap.
• Canvas Transformations : Combines Translate, Rotate, Scale in one stack.

[ Animation & Performance ]

• Idle-Skip Physics : Skips heavy interpolation math if no slide is dirty (IsDirty flag), saving CPU when idle. (0% cpu/gpu)
• Exponential Interpolation : Frame-rate independent easing.
• Smooth Alpha Crossfading : Fades old selected out while new glides in.
• Continuous Render Loop : Dedicated background physics thread.

[ Memory & Layout Management ]

• Auto-Scale Caching : Clears and reloads thumbnails on form Resize.
• Critical Sections : Locks arrays to prevent UI/Worker race conditions.

[ Input & Interaction ]

• Advanced Hit Testing : Differentiates clicks on center vs. side images.
• Inertia & Velocity : Swipe physics with smooth snap-to-grid.
• Full Input Support : Keyboard (Arrows, Home/End) and Mouse Wheel.

Sample project and zipped exe included.

Latest Changes:

v0.1 (First Release):
  - Implemented async threaded image loading (ported from Flowmotion).
  - Added smart proximity loading (only loads images near scroll center).
  - Added auto-scale resize handling (reloads thumbnails on resize).
  - Added smooth alpha crossfading for selected items.
  - Fixed thread initialization exceptions.