`long double` support for ImageIO, MeshIO pixels?

[blowekamp (Bradley Lowekamp)]

@Niels_Dekker

Currently IOComponent has distinct enum values for two char types: CHAR and UCHAR. I think it would be easier if we would have an extra enum value for SIGNED_CHAR, because in C++ char and signed char are distinct type. And then unconditionally map char to CHAR, and signed char to SIGNED_CHAR, right? Or would that break too much legacy code?

It sounds like you are thinking the CHAR enum is describing the char C type ( which is incorrect). The actual usage of it is to describe a signed char/8-bit type. Changing the definition of the CHAR enum would not be good. Perhaps adding an alias of “SIGNED_CHAR == CHAR” would be descriptive and useful.

Also 8-bit integers are only signed or unsigned. The three states of C’s “char” types is an artifact of C and not data. The ImageIO interface really should be describing what is stored on the disk and not the state of types and sizes at programming language level, IMHO. That is to say I have a long term frustration with this interface not providing fixed width integer types.