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authorFlorian Jung <flo@thinkpad.(none)>2011-01-14 13:38:54 +0100
committerFlorian Jung <flo@thinkpad.(none)>2011-01-14 13:38:54 +0100
commitb2d0c97e0ca7b7eb0a7195ddbf263b9953171e66 (patch)
tree00ecb19be6f349196b8c14085ff3325b074677c2 /synth/lfos.cpp
parenta43a4e27a2ba3c34bac5a215ce49175b22913bd4 (diff)
Moved lfos and sample-and-hold in own source file
Diffstat (limited to 'synth/lfos.cpp')
-rw-r--r--synth/lfos.cpp77
1 files changed, 77 insertions, 0 deletions
diff --git a/synth/lfos.cpp b/synth/lfos.cpp
new file mode 100644
index 0000000..5916937
--- /dev/null
+++ b/synth/lfos.cpp
@@ -0,0 +1,77 @@
+#include <math.h>
+#include <stdlib.h>
+
+#include "lfos.h"
+#include "globals.h"
+#include "fixed.h"
+#include "defines.h"
+
+void uninit_lfo(int i)
+{
+ if (lfo[i])
+ {
+ for (int j=0;j<lfo_res[i];j++)
+ delete [] lfo[i][j];
+
+ delete [] lfo[i];
+ lfo[i]=NULL;
+ }
+}
+
+void init_lfo(int i)
+{
+ //two possible divisions by zero are avoided, because
+ //values <= 0 will make the program use the default
+ //(nonzero) values.
+ lfo_res[i]=samp_rate/lfo_freq_hz[i]/lfo_update_frames;
+
+ lfo[i]=new fixed_t* [lfo_res[i]];
+ for (int j=0;j<lfo_res[i];j++)
+ {
+ lfo[i][j]=new fixed_t [N_LFO_LEVELS];
+ float temp=sin(j*2.0*3.141592654/lfo_res[i]);
+ for (int k=0;k<N_LFO_LEVELS;k++)
+ lfo[i][j][k]= (1.0 + temp*(float(LFO_MAX)*k/N_LFO_LEVELS)) * ONE;
+ }
+
+}
+
+void init_snh()
+{
+ sample_and_hold_frames=samp_rate/snh_freq_hz;
+}
+
+void maybe_calc_lfos()
+{
+ static int lfocnt=0;
+ static int snhcnt=0;
+
+ if (lfocnt==0)
+ {
+ lfocnt=lfo_update_frames;
+
+ for (int i=0;i<N_LFOS;i++)
+ {
+ lfo_phase[i]=(lfo_phase[i]+1)%lfo_res[i];
+ curr_lfo[i]=lfo[i][lfo_phase[i]];
+ }
+ }
+
+ if (snhcnt==0)
+ {
+ snhcnt=sample_and_hold_frames;
+
+ //temp ranges between -ONE and ONE
+ fixed_t temp = (float(rand())/(RAND_MAX/2) - 1.0) * ONE;
+
+ for (int i=0;i<N_LFO_LEVELS;i++)
+ sample_and_hold[i]= temp*i/(N_LFO_LEVELS-1) + ONE;
+
+ curr_lfo[SNH_LFO]=sample_and_hold;
+ // could be moved to some init function, but looks clearer and
+ // does not eat up the cpu too much ;)
+ }
+
+ lfocnt--;
+ snhcnt--;
+}