Move the pcsound library to the top level, alongside textscreen.

Subversion-branch: /trunk/chocolate-doom
Subversion-revision: 849

5 files changed, 463 insertions, 0 deletions

diff --git a/pcsound/Makefile.am b/pcsound/Makefile.am
new file mode 100644
index 00000000..77957d72
--- /dev/null
+++ b/pcsound/Makefile.am
@@ -0,0 +1,10 @@
+
+AM_CFLAGS= @SDL_CFLAGS@ @SDLMIXER_CFLAGS@
+
+noinst_LIBRARIES=libpcsound.a
+
+libpcsound_a_SOURCES =                            \
+        pcsound.c           pcsound.h             \
+        pcsound_sdl.c                             \
+        pcsound_win32.c     
+
diff --git a/pcsound/pcsound.c b/pcsound/pcsound.c
new file mode 100644
index 00000000..9c18eb01
--- /dev/null
+++ b/pcsound/pcsound.c
@@ -0,0 +1,114 @@
+// Emacs style mode select   -*- C++ -*- 
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2007 Simon Howard
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either version 2
+// of the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+//
+// DESCRIPTION:
+//    PC speaker interface.
+//
+//-----------------------------------------------------------------------------
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "pcsound.h"
+
+#ifdef _WIN32
+extern pcsound_driver_t pcsound_win32_driver;
+#endif
+extern pcsound_driver_t pcsound_sdl_driver;
+
+static pcsound_driver_t *drivers[] = 
+{
+#ifdef _WIN32
+    &pcsound_win32_driver,
+#endif
+    &pcsound_sdl_driver,
+    NULL,
+};
+
+static pcsound_driver_t *pcsound_driver = NULL;
+
+int PCSound_Init(pcsound_callback_func callback_func)
+{
+    char *driver_name;
+    int i;
+
+    if (pcsound_driver != NULL)
+    {
+        return 1;
+    }
+
+    // Check if the environment variable is set
+
+    driver_name = getenv("PCSOUND_DRIVER");
+
+    if (driver_name != NULL)
+    {
+        for (i=0; drivers[i] != NULL; ++i)
+        {
+            if (!strcasecmp(drivers[i]->name, driver_name))
+            {
+                // Found the driver!
+
+                if (drivers[i]->init_func(callback_func))
+                {
+                    pcsound_driver = drivers[i];
+                }
+                else
+                {
+                    printf("Failed to initialise PC sound driver: %s\n",
+                           drivers[i]->name);
+                    break;
+                }
+            }
+        }
+    }
+    else
+    {
+        // Try all drivers until we find a working one
+
+        for (i=0; drivers[i] != NULL; ++i)
+        {
+            if (drivers[i]->init_func(callback_func)) 
+            {
+                pcsound_driver = drivers[i];
+                break;
+            }
+        }
+    }
+    
+    if (pcsound_driver != NULL)
+    {
+        printf("Using PC sound driver: %s\n", pcsound_driver->name);
+        return 1;
+    }
+    else
+    {
+        printf("Failed to find a working PC sound driver.\n");
+        return 0;
+    }
+}
+
+void PCSound_Shutdown(void)
+{
+    pcsound_driver->shutdown_func();
+    pcsound_driver = NULL;
+}
+
diff --git a/pcsound/pcsound.h b/pcsound/pcsound.h
new file mode 100644
index 00000000..1adee416
--- /dev/null
+++ b/pcsound/pcsound.h
@@ -0,0 +1,45 @@
+// Emacs style mode select   -*- C++ -*- 
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2007 Simon Howard
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either version 2
+// of the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+//
+// DESCRIPTION:
+//    PC speaker interface.
+//
+//-----------------------------------------------------------------------------
+
+#ifndef PCSOUND_H
+#define PCSOUND_H
+
+typedef struct pcsound_driver_s pcsound_driver_t;
+typedef void (*pcsound_callback_func)(int *duration, int *frequency);
+typedef int (*pcsound_init_func)(pcsound_callback_func callback);
+typedef void (*pcsound_shutdown_func)(void);
+
+struct pcsound_driver_s
+{
+    char *name;
+    pcsound_init_func init_func;
+    pcsound_shutdown_func shutdown_func;
+};
+
+int PCSound_Init(pcsound_callback_func callback_func);
+void PCSound_Shutdown(void);
+
+#endif /* #ifndef PCSOUND_H */
+
diff --git a/pcsound/pcsound_sdl.c b/pcsound/pcsound_sdl.c
new file mode 100644
index 00000000..50820394
--- /dev/null
+++ b/pcsound/pcsound_sdl.c
@@ -0,0 +1,179 @@
+// Emacs style mode select   -*- C++ -*- 
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2007 Simon Howard
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either version 2
+// of the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+//
+// DESCRIPTION:
+//    PC speaker interface.
+//
+//-----------------------------------------------------------------------------
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "SDL.h"
+#include "SDL_mixer.h"
+
+#include "pcsound.h"
+
+#define SQUARE_WAVE_AMP 0x2000
+
+static pcsound_callback_func callback;
+
+// Output sound format
+
+static int mixing_freq;
+static Uint16 mixing_format;
+static int mixing_channels;
+
+// Currently playing sound
+// current_remaining is the number of remaining samples that must be played
+// before we invoke the callback to get the next frequency.
+
+static int current_remaining;
+static int current_freq;
+
+static int phase_offset = 0;
+
+// Mixer function that does the PC speaker emulation
+
+static void PCSound_Mix_Callback(void *udata, Uint8 *stream, int len)
+{
+    Sint16 *leftptr;
+    Sint16 *rightptr;
+    Sint16 this_value;
+    int oldfreq;
+    int i;
+    int nsamples;
+
+    // Number of samples is quadrupled, because of 16-bit and stereo
+
+    nsamples = len / 4;
+
+    leftptr = (Sint16 *) stream;
+    rightptr = ((Sint16 *) stream) + 1;
+    
+    // Fill the output buffer
+
+    for (i=0; i<nsamples; ++i)
+    {
+        // Has this sound expired? If so, invoke the callback to get 
+        // the next frequency.
+
+        while (current_remaining == 0) 
+        {
+            oldfreq = current_freq;
+
+            // Get the next frequency to play
+
+            callback(&current_remaining, &current_freq);
+
+            if (current_freq != 0)
+            {
+                // Adjust phase to match to the new frequency.
+                // This gives us a smooth transition between different tones,
+                // with no impulse changes.
+
+                phase_offset = (phase_offset * oldfreq) / current_freq;
+            }
+
+            current_remaining = (current_remaining * mixing_freq) / 1000;
+        }
+
+        // Set the value for this sample.
+        
+        if (current_freq == 0)
+        {
+            // Silence
+
+            this_value = 0;
+        }
+        else 
+        {
+            int frac;
+
+            // Determine whether we are at a peak or trough in the current
+            // sound.  Multiply by 2 so that frac % 2 will give 0 or 1 
+            // depending on whether we are at a peak or trough.
+
+            frac = (phase_offset * current_freq * 2) / mixing_freq;
+
+            if ((frac % 2) == 0) 
+            {
+                this_value = SQUARE_WAVE_AMP;
+            }
+            else
+            {
+                this_value = -SQUARE_WAVE_AMP;
+            }
+
+            ++phase_offset;
+        }
+
+        --current_remaining;
+
+        // Use the same value for the left and right channels.
+
+        *leftptr += this_value;
+        *rightptr += this_value;
+
+        leftptr += 2;
+        rightptr += 2;
+    }
+}
+
+static int PCSound_SDL_Init(pcsound_callback_func callback_func)
+{
+    // Check that SDL_mixer has been opened already
+    // If not, fail
+
+    if (!Mix_QuerySpec(&mixing_freq, &mixing_format, &mixing_channels))
+    {
+        return 0;
+    }
+
+    // Only supports AUDIO_S16SYS
+
+    if (mixing_format != AUDIO_S16SYS || mixing_channels != 2)
+    {
+        fprintf(stderr, 
+                "PCSound_SDL only supports native signed 16-bit LSB, "
+                "stereo format!\n");
+        return 0;
+    }
+
+    callback = callback_func;
+    current_freq = 0;
+    current_remaining = 0;
+
+    Mix_SetPostMix(PCSound_Mix_Callback, NULL);
+
+    return 1;
+}
+
+static void PCSound_SDL_Shutdown(void)
+{
+}
+
+pcsound_driver_t pcsound_sdl_driver = 
+{
+    "SDL",
+    PCSound_SDL_Init,
+    PCSound_SDL_Shutdown,
+};
+
diff --git a/pcsound/pcsound_win32.c b/pcsound/pcsound_win32.c
new file mode 100644
index 00000000..090c0bbd
--- /dev/null
+++ b/pcsound/pcsound_win32.c
@@ -0,0 +1,115 @@
+// Emacs style mode select   -*- C++ -*- 
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2007 Simon Howard
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either version 2
+// of the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+//
+// DESCRIPTION:
+//    PC speaker interface.
+//
+//-----------------------------------------------------------------------------
+
+#ifdef _WIN32
+
+#include <SDL.h>
+#include <windows.h>
+
+#include "pcsound.h"
+
+static SDL_Thread *sound_thread_handle;
+static int sound_thread_running;
+static pcsound_callback_func callback;
+
+static int SoundThread(void *unused)
+{
+    int frequency;
+    int duration;
+    
+    while (sound_thread_running)
+    {
+        callback(&duration, &frequency);
+
+        if (frequency != 0) 
+        {
+            Beep(frequency, duration);
+        }
+        else
+        {
+            Sleep(duration);
+        }
+    }
+    
+    return 0;    
+}
+
+static int PCSound_Win32_Init(pcsound_callback_func callback_func)
+{
+    OSVERSIONINFO osvi;
+    BOOL result;
+
+    // Temporarily disabled - the Windows scheduler is strange and 
+    // stupid.
+   
+    return 0;
+
+    // Find the OS version
+
+    osvi.dwOSVersionInfoSize = sizeof(osvi);
+
+    result = GetVersionEx(&osvi);
+
+    if (!result)
+    {
+        return 0;
+    }
+
+    // Beep() ignores its arguments on win9x, so this driver will
+    // not work there.
+
+    if (osvi.dwPlatformId != VER_PLATFORM_WIN32_NT)
+    {
+        // TODO: Use _out() to write directly to the PC speaker on
+        // win9x: See PC/winsound.c in the Python standard library.
+
+        return 0;
+    }
+    
+    // Start a thread to play sound.
+
+    callback = callback_func;
+    sound_thread_running = 1;
+
+    sound_thread_handle = SDL_CreateThread(SoundThread, NULL);
+
+    return 1;
+}
+
+static void PCSound_Win32_Shutdown(void)
+{
+    sound_thread_running = 0;
+    SDL_WaitThread(sound_thread_handle, NULL);
+}
+
+pcsound_driver_t pcsound_win32_driver = 
+{
+    "Windows",
+    PCSound_Win32_Init,
+    PCSound_Win32_Shutdown,
+};
+
+#endif /* #ifdef _WIN32 */
+