moin all,
fwiw, I'll add my vote in favor of getting Martin's [str] / blob patch into pd vanilla. iirc, Miller has indicated in the past that he feels this sort of thing should be done using arrays. There are a couple of proof-of-concept objects (not compiled by default) in pdstring (moocow/pdstring for pd-extended users) that use arrays, but I wasn't satisfied with this approach for two reasons:
- If you treat the array internally as a string of bytes (e.g. char*),
then: (A) you must constantly cast and re-cast the data (B) you must scale all size attributes (e.g. for re-allocation) by 1.0/sizeof(t_float), so to get an accurate byte length that is not a multiple of sizeof(t_float), you need to actually store that length additionally somewhere else (C) saving array data with a patch and re-loading can cause data loss (float truncation may mess up raw byte values) (D) it's not really portable (byte order problems with load/save)
- If otoh you let the array remain a t_float* and just assign the
floats byte ((unsigned) char) or even wide character (wchar) values, then: (A) you potentially waste a lot of memory (strlen(str)*(sizeof(float)-1) bytes) (B) I/O: if you read a string as a (char*) -- e.g. from a file, socket, external library, etc. -- or if you need a pd-array-string as a (char*) -- e.g. for an external API call -- then you have to explicitly convert it, which means allocating some memory (maybe defining a static local buffer to avoid malloc() calls), and iterating over the string (rsp. over the array), which is O(N) time and space, and is annoying for long strings and/or frequent calls (C) if you really want to store your string data in an array, you can use [str] or [pdstring] together with e.g. [tabdump] and [tabset] from zexy, which just makes the conversion overhead explicit.
I think there are workarounds for both techniques, but not without patching the pd core code, and if we're going to patch the core code, we might as well take a patch that does the job "right" (i.e. Martin's)...
just my €0.02 ...
marmosets, Bryan
On 2011-01-28 09:59:39, Roman Haefeli reduzent@gmail.com appears to have written:
On Wed, 2011-01-26 at 22:54 +0100, João Pais wrote:
For converting, I like moocow/any2bytes and moocow/bytes2any.
I think I had a look at it as well. do you have any comparative reason for
that one instead of the other? or it was just the first one to get to you?One important thing to know is that [mrpeach/str] only works with Pd-extended, but not with Pd-vanilla as it requires some modifications to m_pd.h.
Btw.... @Martin: Do you think it's time again to to try to get the blob support into Pd-vanilla? I think that [str] would be utterly useful also in vanilla and it didn't seem to have caused any problem in Pd-extended, did it?
Roman
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