On Thu, 21 Apr 2011, Marco van de Voort wrote:
In our previous episode, Michael Van Canneyt said:
The best we can do is create a memory class with some pre-defined memory
storages,
with appropriate getscanline/setscanline routines and make sure the reader
classes
can
a) detect them
b) make use of them if they find one matching the file storage format.
c) fall back on the current mechanism if no fitting format is found.
If well-chosen, this approach should cover most cases.
Something like that yes. Still duplication for the various formats though.
I don't see where the duplication comes in.
It allows to address multiple points in the imagesize vs reader/writer class
matrix (that you described) in one source.
There may be duplication in your classes (I don't know, but I suspect it is
delegation classes I think there is no need for duplication...
Basically I use delegation for the slow case, where you operate on the base
type.
However when implemented using generics you can also directly use the
specialized type, and have fairly quick direct access.
You don't need generics for that. Any form of an array of bytes will do,
since that's what it amounts to in the end anyway.
The thing will be to parametrize the needed storage formats, and then implement
the reader support for them.
How will you implement reader support for many memory layouts?
I am not that definite in my design. But I'm willing to listen to ideas.
(barring the ones relying on the use of generics)
Michael.
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