How a TileScheduler cuts pages into tiles, how far it renders ahead and how much memory it may use.
public sealed class TileSchedulerOptions
Spec #33 viewer capabilities 1, 3 and 13. Mutable and fluent like the other options objects: Use* selects an implementation,
With* sets a value. A scheduler copies the values when it is created.
kind:method, kind:property, kind:ctor. Press Esc to clear.DefaultMemoryBudgetThe default MemoryBudget: 256 MiB.DefaultPlaceholderScaleThe default PlaceholderScale: a quarter of a pixel per point (18 DPI).DefaultTileSizeThe default TileSize: 256 pixels.MaxConcurrencyGets or sets how many tiles render at once on a multi-threaded host (by default one less than the processor count, at least one, so the UI thread keeps a core). A cooperative session draws one tile at a time.MemoryBudgetGets or sets the one memory budget in bytes covering the tiles the surface holds, the tiles being drawn, and the document's render caches with their display lists (CachedBytes; DefaultMemoryBudget by default). Choose at least twice the pixels of a screenful of tiles.NearMarginGets or sets the pixels around the viewport, on every side, whose tiles are rendered after the visible ones (one tile by default).ObserverGets or sets a receiver of the scheduler's trace: every tile started, presented, cancelled, evicted or failed, with the bytes accounted right after; null (the default) traces nothing. Called synchronously while the scheduler holds its lock, so keep it short.PlaceholderScaleGets or sets the scale, in pixels per point, of the low-resolution whole-page tile drawn before a page's sharp tiles (DefaultPlaceholderScale by default; 0 turns placeholders off). Placeholders are drawn only at zooms above it and do not depend on the zoom, so a surface can stretch them while the sharp tiles of a new zoom arrive.RenderAheadGets or sets how many viewports beyond the visible one, in the scroll direction, are rendered last (1 by default; 0 turns look-ahead off).SeparateOverlaysGets or sets whether the annotation and form-field layers render as their own transparent tiles over content-only tiles (false by default: one tile holds every shown layer). Separate overlays cost a second tile per region, and in return SetLayers(DisplayLayers) and annotation edits redraw only the overlays.TileSizeGets or sets the side of a tile in device pixels (DefaultTileSize by default).