[gdal-dev] Overriding IRasterIO in class derived from GDALRasterBand

Tamas Szekeres szekerest at gmail.com
Fri Aug 7 16:32:56 EDT 2009


Just thinking out loadly;

Wouldn't it be easier to implement that cache at the driver level, just by
composing the raster in a temp image buffer and feed that image in the
subsequent IReadBlock calls? I think we should also think about the non
regular and overlapping blocks which should also be covered by the
implementation here.

Best regards,

Tamas




2009/8/7 Tamas Szekeres <szekerest at gmail.com>

>
>
> 2009/8/7 Jorge Arévalo <jorge.arevalo at gmail.com>
>
>>
>> > One issue with this concept would be related to the limited memory size
>> of
>> > the particular machine, it may be more reasonable to copy the retrieved
>> > blocks directly onto the output buffer if possible. In this case you
>> cannot
>> > much rely on the base RasterIO implementation.
>>
>> So, you suggest to copy the block data into the buffer without calling
>> base implementation of IRasterIO, do you? This implies take care of
>> the endianess and pixel size "by hand".
>>
>
> And many more... I agree this wouldn't be that straightforward. Populating
> the block buffer would be much easier.
>
> Best regards,
>
> Tamas
>
>
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