Re: [gdal-dev] Thread-safe raster access

2024-06-05 Thread Andrew Bell via gdal-dev
Hi all, Thanks for the thoughts. >From an algorithmic perspective, it's frustrating to have to wait to read/write data. There are ways, up to a point, to avoid some of this with the current interface, but it can make applications complicated and for algorithms that can process blocks separately,

Re: [gdal-dev] Thread-safe raster access

2024-06-05 Thread Deyan Vasilev via gdal-dev
Hi, I've written a piece of software that fetches tiles out of a single MBTiles raster done by multiple threads. Tiles go to a common cache which can be used by a "view" thread that assembles tiles on the screen in a seamless map. Each fetcher thread uses GDALOpenEx() and then RasterIO(GF_Read,,,)

Re: [gdal-dev] gdaladdo slowness for VRTs

2024-06-05 Thread Rahkonen Jukka via gdal-dev
Hi, A better reference file can be created by materializing the VRT. The one created by gdal_create has the same raster values on all the pixels but the materialized one contains the same original image data. Maybe in your test case with uncompressed outputs the difference is not so big, but pl