bytemedia

commit: d76bf60d58c72a65c018fe6335d6b8e2cae8dd59
parent 186129564113e2d3996b5f94ead92ecbf8a7e8a9
Author: Haelwenn (lanodan) Monnier <contact@hacktivis.me>
Date:   Sun,  9 Jan 2022 12:31:44 +0100

c/kagome_kagome: Sinusoidal version

Diffstat:
M
C/kagome_kagome.c
60
++++++++++++++++++++++++++++++++++++++++++++++++++++++------

1 file changed, 54 insertions(+), 6 deletions(-)
diff --git a/C/kagome_kagome.c b/C/kagome_kagome.c
@@ -1,19 +1,61 @@
-#define _POSIX_C_SOURCE 200809L
+//#define _POSIX_C_SOURCE 200809L
+#define _XOPEN_SOURCE 700
 #include <stdio.h>
 #include <inttypes.h> // uint32_t
+#include <math.h> // sinf(), M_PI, pow()
+#include <stdlib.h> // abort()
 
 #include "au.h"
 
 #define TICK 3600
-#define NOTE (TICK*1)
-#define GAP (TICK*0)
+#define NOTE (TICK*0.99)
+#define GAP (TICK*0.01)
+
+// taken from beep(1) manpage
+#define MID_C_C  261.63
+#define MID_C_CS 277.18
+#define MID_C_DB 277.18
+#define MID_C_D  293.66
+#define MID_C_DS 311.13
+#define MID_C_EB 311.13
+#define MID_C_E  329.63
+#define MID_C_F  349.23
+#define MID_C_FS 369.99
+#define MID_C_FB 369.99
+#define MID_C_G  392.00
+#define MID_C_GS 415.30
+#define MID_C_AB 415.30
+#define MID_C_A  440.00
+#define MID_C_AS 466.16
+#define MID_C_BB 466.16
+#define MID_C_B  493.88
+
+// https://pages.mtu.edu/~suits/NoteFreqCalcs.html
+#define TWELTH_ROOT_2 1.059463094359
+double
+note_to_hertz(double ref_tune, int steps) {
+	return ref_tune*pow(TWELTH_ROOT_2,steps);
+}
+
+void
+sin_note(int dur, struct au_header *header, int hertz, float volume, float delay) {
+	char buf[4];
+
+	for(int t = 0;t<dur;t++) {
+		putchar((uint8_t)(sinf((delay + t) * 2*M_PI*hertz/header->samplerate) * volume));
+	}
+}
 
+#if 0
 void
 note(int dur, int pitch) {
 	for(int t = 0;t<dur;t++) {
 		putchar( t*pitch );
 	}
 }
+#else
+#define note(dur,pitch) sin_note(dur, header, note_to_hertz(440, pitch-8), 75, 0)
+#endif
 
 void
 silence(int dur) {
@@ -21,7 +63,7 @@ silence(int dur) {
 }
 
 void
-kagome() {
+kagome(struct au_header *header) {
 	note(NOTE*2, 8); silence(GAP*2);
 
 	note(NOTE*1, 8); silence(GAP);
@@ -162,8 +204,14 @@ main(void)
 	// fd 1 is stdout
 	write_au_header(1, &header);
 
-	kagome();
-	kagome();
+	kagome(&header);
+	kagome(&header);
+
+	//       dur    pt  vol del
+	//sin_note(header.samplerate, &header, 440, 150, 0);
+	//sin_note(header.samplerate/2, &header, note_to_hertz(440, 0), 150, 0);
+	//sin_note(header.samplerate/4, &header, note_to_hertz(440, 1), 150, 0);
+	//sin_note(header.samplerate/4, &header, note_to_hertz(440, 1), 150, 0);
 
 	return 0;
 }