[PD-dev] dsp_tick() in d_ugen.c

Hello, brothers! Tudo beleza?

I'm trying to understand the DSP scheduling. I think my questions are similar to Tim Blechmann ones two years before: http://lists.puredata.info/pipermail/pd-dev/2004-04/002407.html

Please, help me:

someone calls canvas_dodsp function (question 1: who? when?)

g_canvas.c canvas_dodsp (...) { /* create a new "DSP graph" object to use in sorting this canvas. dc = ugen_start_graph(...);

/* finally, sort them and add them to the DSP chain */ ugen_done_graph(dc); }

d_ugen.c ugen_done_graph (...) { ugendoit() for each unit }

ugen_doit (...) {

calls mess1(&u->u_obj->ob_pd, gensym("dsp"), insig) --> question 2: This is calling dsp_add() to add each dsp object perform function in dsp_chain. Isnt it?

question 3: So, does it call "canvas_dodsp" when the object is the canvas? (If yes this answers question 1). :D

}

But my main doubt is:

question 4: where is the code which finally execute the dsp calculations, i. e. the code which call the perform functions of each object?

I think is this one, called by Pd main loop: m_scheduler() which calls sched_tick() which calls dsp_tick()

void dsp_tick(void) { if (dsp_chain) { t_int *ip; for (ip = dsp_chain; *ip; ) ip = (*(t_perfroutine)(*ip))(ip); ---> chain execution? dsp_phase++; } }

is it correct?

THANX, BRO!

j.jR.