Re: [gdal-dev] Update on RFC 62: Raster algebra

2016-09-23 Thread Alex HighViz
>> Richard Barnes: >>In building tile/block managers, I too have found it difficult to use >>iterators or design algorithms without specifically considering both >>tiles/blocks >>and cells. Without doing so, it is very easy to write code >>which is (extremely) cache inefficient. I think that

Re: [gdal-dev] Update on RFC 62: Raster algebra

2016-09-22 Thread Richard Barnes
In building tile/block managers, I too have found it difficult to use iterators or design algorithms without specifically considering both tiles/blocks and cells. Without doing so, it is very easy to write code which is (extremely) cache inefficient. I'm not sure if flow algebras have arisen i

Re: [gdal-dev] Update on RFC 62: Raster algebra

2016-09-22 Thread Ari Jolma
13.09.2016, 15:40, alex kirjoitti: Ari Wrote: At FOSS4G my conclusion was that my first approach was not good for many reasons, most >importantly because it did not scale to several bands in one operation. So I've trying with the >following ideas/decisions: The problem is to compute y=f(x1, x2

Re: [gdal-dev] Update on RFC 62: Raster algebra

2016-09-13 Thread alex
>Ari Wrote: >At FOSS4G my conclusion was that my first approach was not good for many >reasons, most >importantly because it did not scale to several bands in one >operation. So I've trying with the >following ideas/decisions: > >The problem is to compute y=f(x1, x2, ...), where y is a new datase

Re: [gdal-dev] Update on RFC 62: Raster algebra

2016-09-13 Thread Ari Jolma
13.09.2016, 13:14, Even Rouault kirjoitti: Le mardi 13 septembre 2016 10:15:42, Ari Jolma a écrit : There's been some discussion here about doing pixel function calculations in VRT derived bands, so I thought I'd let you know what are my thoughts and what I've done regarding RFC 62. At FOSS4G m

Re: [gdal-dev] Update on RFC 62: Raster algebra

2016-09-13 Thread Even Rouault
Le mardi 13 septembre 2016 10:15:42, Ari Jolma a écrit : > There's been some discussion here about doing pixel function > calculations in VRT derived bands, so I thought I'd let you know what > are my thoughts and what I've done regarding RFC 62. > > At FOSS4G my conclusion was that my first appro

[gdal-dev] Update on RFC 62: Raster algebra

2016-09-13 Thread Ari Jolma
There's been some discussion here about doing pixel function calculations in VRT derived bands, so I thought I'd let you know what are my thoughts and what I've done regarding RFC 62. At FOSS4G my conclusion was that my first approach was not good for many reasons, most importantly because it