Changeset 2430:cd4e4e0562a4 in roaraudio

Timestamp:

08/19/09 06:02:58 (15 years ago)

Author:

phi

Branch:

default

Phase:

public

Message:

added some basic SYNFs

Files:

• include/libroardsp/synth.h (modified) (2 diffs)
• libroardsp/synth.c (modified) (1 diff)

include/libroardsp/synth.h

@@ -43 +43 @@
 // SYNF -> Synthesis Function
 #define ROAR_SYNTH_SYNF_SINE ROAR_SYNTH_FUNC_CAST(sinf)
+#define ROAR_SYNTH_SYNF_RECT ROAR_SYNTH_FUNC_CAST(roar_synth_synf_rect)
+#define ROAR_SYNTH_SYNF_SAW  ROAR_SYNTH_FUNC_CAST(roar_synth_synf_saw)
+#define ROAR_SYNTH_SYNF_TRI  ROAR_SYNTH_FUNC_CAST(roar_synth_synf_tri)
+#define ROAR_SYNTH_SYNF_TRAP ROAR_SYNTH_FUNC_CAST(roar_synth_synf_trap)
 
 struct roar_synth_state {
@@ -58 +62 @@
 int roar_synth_pcmout_i161(struct roar_synth_state * state, int16_t * out, size_t frames);
 
+// some basic SYNFs:
+float roar_synth_synf_rect (float t, struct roar_synth_state * state);
+float roar_synth_synf_saw  (float t, struct roar_synth_state * state);
+float roar_synth_synf_tri  (float t, struct roar_synth_state * state);
+float roar_synth_synf_trap (float t, struct roar_synth_state * state);
+
 #endif
 

libroardsp/synth.c

@@ -98 +98 @@
 }
 
+// basic SINFs:
+float roar_synth_synf_rect (float t, struct roar_synth_state * state) {
+ t /= 2*M_PI;
+ t -= (int)t;
+
+ if ( t < 0.5 )
+  return  1;
+ else
+  return -1;
+}
+
+float roar_synth_synf_saw  (float t, struct roar_synth_state * state) {
+ t /= 2*M_PI;
+ t -= (int)t;
+
+ return 2*t - 1;
+}
+
+float roar_synth_synf_tri  (float t, struct roar_synth_state * state) {
+ t /= 2*M_PI;
+ t -= (int)t;
+
+ if ( t < 0.5 )
+  return   4* t      - 1;
+ else
+  return  -4*(t-0.5) + 1;
+}
+
+float roar_synth_synf_trap (float t, struct roar_synth_state * state) {
+ t /= 2*M_PI;
+ t -= (int)t;
+
+ if ( t < 0.125 || t > 0.875 ) {
+  return -1;
+ } else if ( t < 0.625 && t > 0.375 ) {
+  return  1;
+ } else if ( t < 0.5 ) {
+  return  8*(t-0.375) + 1;
+ } else {
+  return -8*(t-0.625) + 1;
+ }
+}
 
 //ll