THotPDF.RenderLoadedPageBandsParallel Method
使用整宽水平 band,并沿用与并行 tile 渲染相同的有序 callback、共享缓存、取消和内存预算契约
声明
function RenderLoadedPageBandsParallel(PageIndex, DPI,
BandHeightPixels, MaxConcurrency: Integer; MaxWorkingBytes: Int64;
Callback: THPDFRenderTileEvent): Integer; overload;
function RenderLoadedPageBandsParallel(PageIndex, DPI,
BandHeightPixels, MaxConcurrency: Integer; MaxWorkingBytes: Int64;
Callback: THPDFRenderTileEvent;
out Info: THPDFParallelTileRenderInfo): Integer; overload;
band 自上而下交付,每个 callback 收到自己的 user-space 边界和借出的 bitmap;触发取消时,所有尚未发布的 worker 与预留都会被释放