Stefano D'Angelo wrote: > I do totally agree, and in fact what I was suggesting looks like: > > struct { > float value; > const char *name; > } ladspa_port_label; > struct ladspa_port_label ** ladspa_get_port_labels(unsigned long > descriptor_index, unsigned long port_index);
We are talking about two different things here. You've described an API to return specific, named points within a range. Kind of tick marks on a slider, with associated labels. So that you can have a slider that has "cold" at zero value, "cool" at 25% and "hot" at 100%. Is that right? The same API could also be used for returning values and descriptions for enum ports (but not continuous ports, as it would require about 2^32 port labels :) ). On the other hand, I'm talking about a basic custom float-to-string function. Something I could implement so that cutoff frequency for my plugin could be formatted as "%0.0f Hz", while the delay time could be formatted as "%0.2fms" for small values and "%0.0fms" for large values. Also, I could use it to format 0 as "Lowpass", 1 as "Highpass", etc., in an integer port that I use for filter type. Which I could, also, mark as "this is enum" with a sort of new hint we were talking about previously. So far, I've seen more uses for formatting continuous values (a little label next to a knob) than providing tick marks for continuous values. However, there's a relatively simple solution to have both: // this gives us text-to-string for arbitrary floats (side effect of which is being able to implement enums) const char *ladspa_format_value(LADSPA_Descriptor *descriptor, int port, float value); // this tells us which float values have "interesting" meaning void ladspa_get_scalepoints(LADSPA_Descriptor *descriptor, int port, /* [out] */ float **values, /* [out] */ int *values_count); It may seem *very slightly* less efficient, but that should be OK, as it's a microseconds-range difference in non-RT code. For "normal" enums and custom-rendered parameters you'd only need the first function anyway. For completeness (I'm probably starting a flamewar here) we might also have a reverse function, like: float ladspa_parse_value(LADSPA_Descriptor *descriptor, int port, const char *value, const char **error); which would allow to convert user-entered values (like delay times in seconds, milliseconds, centuries, Hertz etc. - or frequency ratios in cents, semitones, octaves...) to a float value expected by given port, optionally returning an error message if the text value is illegal. Krzysztof _______________________________________________ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev