From 74af58587359206ef92249d18e4830c40cac0bc5 Mon Sep 17 00:00:00 2001
From: Jedidiah Barber <contact@jedbarber.id.au>
Date: Mon, 19 Jun 2023 22:15:44 +1200
Subject: Initial commit

---
 example/aao_example.adb | 101 ++++++++++++++++++++++++++++++++++++++++++++++++
 example/ao_example.c    |  87 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 188 insertions(+)
 create mode 100644 example/aao_example.adb
 create mode 100644 example/ao_example.c

(limited to 'example')

diff --git a/example/aao_example.adb b/example/aao_example.adb
new file mode 100644
index 0000000..7d12b56
--- /dev/null
+++ b/example/aao_example.adb
@@ -0,0 +1,101 @@
+
+
+--  Programmed by Jedidiah Barber
+--  Released into the public domain
+
+--  This program opens the default libao driver and plays a 440 Hz tone for one second
+
+
+with
+
+    Ada.Command_Line,
+    Ada.Numerics.Elementary_Functions,
+    Ada.Text_IO,
+    Libao;
+
+
+procedure AAO_Example is
+
+    package ACom renames Ada.Command_Line;
+    package Math renames Ada.Numerics.Elementary_Functions;
+    package TIO renames Ada.Text_IO;
+
+    My_Device : Libao.Device;
+    My_Format : Libao.Sample_Format;
+
+    Default_Driver : Libao.Driver_ID_Number;
+
+begin
+
+    --  Initialize
+
+    TIO.Put_Line ("libao example program");
+
+    Libao.Startup;
+
+
+    --  Setup for default driver
+
+    Default_Driver := Libao.Default_Driver_ID;
+
+    My_Format := Libao.Create
+       (Bits           => 16,
+        Rate           => 44100,
+        Channels       => 2,
+        Byte_Format    => Libao.Little_Endian,
+        Channel_Matrix => Libao.Stereo);
+
+
+    --  Open driver
+
+    begin
+        My_Device := Libao.Open_Live
+           (Driver_ID => Default_Driver,
+            Format    => My_Format,
+            Options   => Libao.Empty_Options);
+    exception
+        when Libao.Open_Device_Error | Libao.General_Failure =>
+            TIO.Put_Line ("Error opening device.");
+            ACom.Set_Exit_Status (ACom.Failure);
+            return;
+    end;
+
+
+    --  Play some stuff
+
+    --  This sine wave generation was directly translated from the C example,
+    --  but it ends up being a little messy playing fast and loose like this.
+
+    declare
+        Buffer : Libao.Data_Buffer (1 .. 16 / 8 * 2 * 44100);
+
+        type Wraparound is mod 65536;
+        Sample : Wraparound;
+    begin
+        for I in Integer range 0 .. 44100 - 1 loop
+            Sample := Wraparound (Integer (0.75 * 32768.0 *
+                Math.Sin (2.0 * Ada.Numerics.Pi * 440.0 * Float (I) / 44100.0)) mod 65536);
+
+            --  Put the same stuff in left and right channel
+            Buffer (4 * I + 1) := Character'Val (Sample and 16#FF#);
+            Buffer (4 * I + 2) := Character'Val ((Sample / 256) and 16#FF#);
+            Buffer (4 * I + 3) := Character'Val (Sample and 16#FF#);
+            Buffer (4 * I + 4) := Character'Val ((Sample / 256) and 16#FF#);
+        end loop;
+
+        Libao.Play (My_Device, Buffer);
+    end;
+
+
+    --  Close and shutdown
+
+    --  Technically the binding will take care of closing open devices at shutdown,
+    --  but it is always good practice to close them anyway.
+
+    Libao.Close (My_Device);
+
+    Libao.Shutdown;
+
+end AAO_Example;
+
+
diff --git a/example/ao_example.c b/example/ao_example.c
new file mode 100644
index 0000000..a5642a0
--- /dev/null
+++ b/example/ao_example.c
@@ -0,0 +1,87 @@
+/*
+ *
+ * ao_example.c
+ *
+ *     Written by Stan Seibert - July 2001
+ *
+ * Legal Terms:
+ *
+ *     This source file is released into the public domain.  It is
+ *     distributed without any warranty; without even the implied
+ *     warranty * of merchantability or fitness for a particular
+ *     purpose.
+ *
+ * Function:
+ *
+ *     This program opens the default driver and plays a 440 Hz tone for
+ *     one second.
+ *
+ * Compilation command line (for Linux systems):
+ *
+ *     gcc -o ao_example ao_example.c -lao -ldl -lm
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <ao/ao.h>
+#include <math.h>
+
+#define BUF_SIZE 4096
+
+int main()
+{
+	ao_device *device;
+	ao_sample_format format;
+	int default_driver;
+	char *buffer;
+	int buf_size;
+	int sample;
+	float freq = 440.0;
+	int i;
+
+	/* -- Initialize -- */
+
+	fprintf(stderr, "libao example program\n");
+
+	ao_initialize();
+
+	/* -- Setup for default driver -- */
+
+	default_driver = ao_default_driver_id();
+
+        memset(&format, 0, sizeof(format));
+	format.bits = 16;
+	format.channels = 2;
+	format.rate = 44100;
+	format.byte_format = AO_FMT_LITTLE;
+
+	/* -- Open driver -- */
+	device = ao_open_live(default_driver, &format, NULL /* no options */);
+	if (device == NULL) {
+		fprintf(stderr, "Error opening device.\n");
+		return 1;
+	}
+
+	/* -- Play some stuff -- */
+	buf_size = format.bits/8 * format.channels * format.rate;
+	buffer = calloc(buf_size,
+			sizeof(char));
+
+	for (i = 0; i < format.rate; i++) {
+		sample = (int)(0.75 * 32768.0 *
+			sin(2 * M_PI * freq * ((float) i/format.rate)));
+
+		/* Put the same stuff in left and right channel */
+		buffer[4*i] = buffer[4*i+2] = sample & 0xff;
+		buffer[4*i+1] = buffer[4*i+3] = (sample >> 8) & 0xff;
+	}
+	ao_play(device, buffer, buf_size);
+
+	/* -- Close and shutdown -- */
+	ao_close(device);
+
+	ao_shutdown();
+
+  return (0);
+}
-- 
cgit