[fpc-pascal] Usage of TFPCustomImage

[Juha Manninen]

On Tue, Jun 13, 2017 at 5:20 PM, Michael Van Canneyt
<michael at freepascal.org> wrote:
> However, this method of loading an image depends on the order of the uses
> statements: each registered reader is asked in turn whether it recognizes
> the stream.

The unit IntfGraphics in LCL does not have unit FPReadPNM in its uses clause.
It has: FPReadBMP,  FPReadPNG, FPReadTiff


> The first to answer 'yes' will be used to read the stream. If PNM 'falsely'
> recognizes a PNG stream as PNM, there is nothing you can do except tell the
> reader which format to use...

Ok, I don't know how to do that. I don't even know how TFPCustomImage
should be used without LCL + TLazIntfImage.
"Custom" in its name hints that a derived class should be used.
Somebody else can study what happens in the code.

Juha