view src/joystick/SDL_joystick.c @ 2661:d38309be5178 gsoc2008_audio_resampling

The windowed sinc filter generation code seems to be working fine. The FIR filtering code is also now working reasonably well. Occasionally the FIR filter will pop, but setting the normalization factor lower seems to help this. I suspect the problem is in the fixed point multiply/add. I also have a hunch the zero stuffing/sample discarding code is not correct, and I'll look at that soon to get it sorted out.
author Aaron Wishnick <schnarf@gmail.com>
date Wed, 02 Jul 2008 08:04:50 +0000
parents c121d94672cb
children 96adc8025331
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library 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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* This is the joystick API for Simple DirectMedia Layer */

#include "SDL_events.h"
#include "SDL_sysjoystick.h"
#include "SDL_joystick_c.h"
#if !SDL_EVENTS_DISABLED
#include "../events/SDL_events_c.h"
#endif

/* This is used for Quake III Arena */
#if SDL_EVENTS_DISABLED
#define SDL_Lock_EventThread()
#define SDL_Unlock_EventThread()
#endif

Uint8 SDL_numjoysticks = 0;
SDL_Joystick **SDL_joysticks = NULL;
static SDL_Joystick *default_joystick = NULL;

int
SDL_JoystickInit(void)
{
    int arraylen;
    int status;

    SDL_numjoysticks = 0;
    status = SDL_SYS_JoystickInit();
    if (status >= 0) {
        arraylen = (status + 1) * sizeof(*SDL_joysticks);
        SDL_joysticks = (SDL_Joystick **) SDL_malloc(arraylen);
        if (SDL_joysticks == NULL) {
            SDL_numjoysticks = 0;
        } else {
            SDL_memset(SDL_joysticks, 0, arraylen);
            SDL_numjoysticks = status;
        }
        status = 0;
    }
    default_joystick = NULL;
    return (status);
}

/*
 * Count the number of joysticks attached to the system
 */
int
SDL_NumJoysticks(void)
{
    return SDL_numjoysticks;
}

/*
 * Get the implementation dependent name of a joystick
 */
const char *
SDL_JoystickName(int device_index)
{
    if ((device_index < 0) || (device_index >= SDL_numjoysticks)) {
        SDL_SetError("There are %d joysticks available", SDL_numjoysticks);
        return (NULL);
    }
    return (SDL_SYS_JoystickName(device_index));
}

/*
 * Open a joystick for use - the index passed as an argument refers to
 * the N'th joystick on the system.  This index is the value which will
 * identify this joystick in future joystick events.
 *
 * This function returns a joystick identifier, or NULL if an error occurred.
 */
SDL_Joystick *
SDL_JoystickOpen(int device_index)
{
    int i;
    SDL_Joystick *joystick;

    if ((device_index < 0) || (device_index >= SDL_numjoysticks)) {
        SDL_SetError("There are %d joysticks available", SDL_numjoysticks);
        return (NULL);
    }

    /* If the joystick is already open, return it */
    for (i = 0; SDL_joysticks[i]; ++i) {
        if (device_index == SDL_joysticks[i]->index) {
            joystick = SDL_joysticks[i];
            ++joystick->ref_count;
            return (joystick);
        }
    }

    /* Create and initialize the joystick */
    joystick = (SDL_Joystick *) SDL_malloc((sizeof *joystick));
    if (joystick != NULL) {
        SDL_memset(joystick, 0, (sizeof *joystick));
        joystick->index = device_index;
        if (SDL_SYS_JoystickOpen(joystick) < 0) {
            SDL_free(joystick);
            joystick = NULL;
        } else {
            if (joystick->naxes > 0) {
                joystick->axes = (Sint16 *) SDL_malloc
                    (joystick->naxes * sizeof(Sint16));
            }
            if (joystick->nhats > 0) {
                joystick->hats = (Uint8 *) SDL_malloc
                    (joystick->nhats * sizeof(Uint8));
            }
            if (joystick->nballs > 0) {
                joystick->balls = (struct balldelta *) SDL_malloc
                    (joystick->nballs * sizeof(*joystick->balls));
            }
            if (joystick->nbuttons > 0) {
                joystick->buttons = (Uint8 *) SDL_malloc
                    (joystick->nbuttons * sizeof(Uint8));
            }
            if (((joystick->naxes > 0) && !joystick->axes)
                || ((joystick->nhats > 0) && !joystick->hats)
                || ((joystick->nballs > 0) && !joystick->balls)
                || ((joystick->nbuttons > 0) && !joystick->buttons)) {
                SDL_OutOfMemory();
                SDL_JoystickClose(joystick);
                joystick = NULL;
            }
            if (joystick->axes) {
                SDL_memset(joystick->axes, 0,
                           joystick->naxes * sizeof(Sint16));
            }
            if (joystick->hats) {
                SDL_memset(joystick->hats, 0,
                           joystick->nhats * sizeof(Uint8));
            }
            if (joystick->balls) {
                SDL_memset(joystick->balls, 0,
                           joystick->nballs * sizeof(*joystick->balls));
            }
            if (joystick->buttons) {
                SDL_memset(joystick->buttons, 0,
                           joystick->nbuttons * sizeof(Uint8));
            }
        }
    }
    if (joystick) {
        /* Add joystick to list */
        ++joystick->ref_count;
        SDL_Lock_EventThread();
        for (i = 0; SDL_joysticks[i]; ++i)
            /* Skip to next joystick */ ;
        SDL_joysticks[i] = joystick;
        SDL_Unlock_EventThread();
    }
    return (joystick);
}

/*
 * Returns 1 if the joystick has been opened, or 0 if it has not.
 */
int
SDL_JoystickOpened(int device_index)
{
    int i, opened;

    opened = 0;
    for (i = 0; SDL_joysticks[i]; ++i) {
        if (SDL_joysticks[i]->index == (Uint8) device_index) {
            opened = 1;
            break;
        }
    }
    return (opened);
}

static int
ValidJoystick(SDL_Joystick ** joystick)
{
    int valid;

    if (*joystick == NULL) {
        *joystick = default_joystick;
    }
    if (*joystick == NULL) {
        SDL_SetError("Joystick hasn't been opened yet");
        valid = 0;
    } else {
        valid = 1;
    }
    return valid;
}

/*
 * Get the device index of an opened joystick.
 */
int
SDL_JoystickIndex(SDL_Joystick * joystick)
{
    if (!ValidJoystick(&joystick)) {
        return (-1);
    }
    return (joystick->index);
}

/*
 * Get the number of multi-dimensional axis controls on a joystick
 */
int
SDL_JoystickNumAxes(SDL_Joystick * joystick)
{
    if (!ValidJoystick(&joystick)) {
        return (-1);
    }
    return (joystick->naxes);
}

/*
 * Get the number of hats on a joystick
 */
int
SDL_JoystickNumHats(SDL_Joystick * joystick)
{
    if (!ValidJoystick(&joystick)) {
        return (-1);
    }
    return (joystick->nhats);
}

/*
 * Get the number of trackballs on a joystick
 */
int
SDL_JoystickNumBalls(SDL_Joystick * joystick)
{
    if (!ValidJoystick(&joystick)) {
        return (-1);
    }
    return (joystick->nballs);
}

/*
 * Get the number of buttons on a joystick
 */
int
SDL_JoystickNumButtons(SDL_Joystick * joystick)
{
    if (!ValidJoystick(&joystick)) {
        return (-1);
    }
    return (joystick->nbuttons);
}

/*
 * Get the current state of an axis control on a joystick
 */
Sint16
SDL_JoystickGetAxis(SDL_Joystick * joystick, int axis)
{
    Sint16 state;

    if (!ValidJoystick(&joystick)) {
        return (0);
    }
    if (axis < joystick->naxes) {
        state = joystick->axes[axis];
    } else {
        SDL_SetError("Joystick only has %d axes", joystick->naxes);
        state = 0;
    }
    return (state);
}

/*
 * Get the current state of a hat on a joystick
 */
Uint8
SDL_JoystickGetHat(SDL_Joystick * joystick, int hat)
{
    Uint8 state;

    if (!ValidJoystick(&joystick)) {
        return (0);
    }
    if (hat < joystick->nhats) {
        state = joystick->hats[hat];
    } else {
        SDL_SetError("Joystick only has %d hats", joystick->nhats);
        state = 0;
    }
    return (state);
}

/*
 * Get the ball axis change since the last poll
 */
int
SDL_JoystickGetBall(SDL_Joystick * joystick, int ball, int *dx, int *dy)
{
    int retval;

    if (!ValidJoystick(&joystick)) {
        return (-1);
    }

    retval = 0;
    if (ball < joystick->nballs) {
        if (dx) {
            *dx = joystick->balls[ball].dx;
        }
        if (dy) {
            *dy = joystick->balls[ball].dy;
        }
        joystick->balls[ball].dx = 0;
        joystick->balls[ball].dy = 0;
    } else {
        SDL_SetError("Joystick only has %d balls", joystick->nballs);
        retval = -1;
    }
    return (retval);
}

/*
 * Get the current state of a button on a joystick
 */
Uint8
SDL_JoystickGetButton(SDL_Joystick * joystick, int button)
{
    Uint8 state;

    if (!ValidJoystick(&joystick)) {
        return (0);
    }
    if (button < joystick->nbuttons) {
        state = joystick->buttons[button];
    } else {
        SDL_SetError("Joystick only has %d buttons", joystick->nbuttons);
        state = 0;
    }
    return (state);
}

/*
 * Close a joystick previously opened with SDL_JoystickOpen()
 */
void
SDL_JoystickClose(SDL_Joystick * joystick)
{
    int i;

    if (!ValidJoystick(&joystick)) {
        return;
    }

    /* First decrement ref count */
    if (--joystick->ref_count > 0) {
        return;
    }

    /* Lock the event queue - prevent joystick polling */
    SDL_Lock_EventThread();

    if (joystick == default_joystick) {
        default_joystick = NULL;
    }
    SDL_SYS_JoystickClose(joystick);

    /* Remove joystick from list */
    for (i = 0; SDL_joysticks[i]; ++i) {
        if (joystick == SDL_joysticks[i]) {
            SDL_memcpy(&SDL_joysticks[i], &SDL_joysticks[i + 1],
                       (SDL_numjoysticks - i) * sizeof(joystick));
            break;
        }
    }

    /* Let the event thread keep running */
    SDL_Unlock_EventThread();

    /* Free the data associated with this joystick */
    if (joystick->axes) {
        SDL_free(joystick->axes);
    }
    if (joystick->hats) {
        SDL_free(joystick->hats);
    }
    if (joystick->balls) {
        SDL_free(joystick->balls);
    }
    if (joystick->buttons) {
        SDL_free(joystick->buttons);
    }
    SDL_free(joystick);
}

void
SDL_JoystickQuit(void)
{
    /* Stop the event polling */
    SDL_Lock_EventThread();
    SDL_numjoysticks = 0;
    SDL_Unlock_EventThread();

    /* Quit the joystick setup */
    SDL_SYS_JoystickQuit();
    if (SDL_joysticks) {
        SDL_free(SDL_joysticks);
        SDL_joysticks = NULL;
    }
}


/* These are global for SDL_sysjoystick.c and SDL_events.c */

int
SDL_PrivateJoystickAxis(SDL_Joystick * joystick, Uint8 axis, Sint16 value)
{
    int posted;

    /* Update internal joystick state */
    joystick->axes[axis] = value;

    /* Post the event, if desired */
    posted = 0;
#if !SDL_EVENTS_DISABLED
    if (SDL_ProcessEvents[SDL_JOYAXISMOTION] == SDL_ENABLE) {
        SDL_Event event;
        event.type = SDL_JOYAXISMOTION;
        event.jaxis.which = joystick->index;
        event.jaxis.axis = axis;
        event.jaxis.value = value;
        if ((SDL_EventOK == NULL)
            || (*SDL_EventOK) (SDL_EventOKParam, &event)) {
            posted = 1;
            SDL_PushEvent(&event);
        }
    }
#endif /* !SDL_EVENTS_DISABLED */
    return (posted);
}

int
SDL_PrivateJoystickHat(SDL_Joystick * joystick, Uint8 hat, Uint8 value)
{
    int posted;

    /* Update internal joystick state */
    joystick->hats[hat] = value;

    /* Post the event, if desired */
    posted = 0;
#if !SDL_EVENTS_DISABLED
    if (SDL_ProcessEvents[SDL_JOYHATMOTION] == SDL_ENABLE) {
        SDL_Event event;
        event.jhat.type = SDL_JOYHATMOTION;
        event.jhat.which = joystick->index;
        event.jhat.hat = hat;
        event.jhat.value = value;
        if ((SDL_EventOK == NULL)
            || (*SDL_EventOK) (SDL_EventOKParam, &event)) {
            posted = 1;
            SDL_PushEvent(&event);
        }
    }
#endif /* !SDL_EVENTS_DISABLED */
    return (posted);
}

int
SDL_PrivateJoystickBall(SDL_Joystick * joystick, Uint8 ball,
                        Sint16 xrel, Sint16 yrel)
{
    int posted;

    /* Update internal mouse state */
    joystick->balls[ball].dx += xrel;
    joystick->balls[ball].dy += yrel;

    /* Post the event, if desired */
    posted = 0;
#if !SDL_EVENTS_DISABLED
    if (SDL_ProcessEvents[SDL_JOYBALLMOTION] == SDL_ENABLE) {
        SDL_Event event;
        event.jball.type = SDL_JOYBALLMOTION;
        event.jball.which = joystick->index;
        event.jball.ball = ball;
        event.jball.xrel = xrel;
        event.jball.yrel = yrel;
        if ((SDL_EventOK == NULL)
            || (*SDL_EventOK) (SDL_EventOKParam, &event)) {
            posted = 1;
            SDL_PushEvent(&event);
        }
    }
#endif /* !SDL_EVENTS_DISABLED */
    return (posted);
}

int
SDL_PrivateJoystickButton(SDL_Joystick * joystick, Uint8 button, Uint8 state)
{
    int posted;
#if !SDL_EVENTS_DISABLED
    SDL_Event event;

    switch (state) {
    case SDL_PRESSED:
        event.type = SDL_JOYBUTTONDOWN;
        break;
    case SDL_RELEASED:
        event.type = SDL_JOYBUTTONUP;
        break;
    default:
        /* Invalid state -- bail */
        return (0);
    }
#endif /* !SDL_EVENTS_DISABLED */

    /* Update internal joystick state */
    joystick->buttons[button] = state;

    /* Post the event, if desired */
    posted = 0;
#if !SDL_EVENTS_DISABLED
    if (SDL_ProcessEvents[event.type] == SDL_ENABLE) {
        event.jbutton.which = joystick->index;
        event.jbutton.button = button;
        event.jbutton.state = state;
        if ((SDL_EventOK == NULL)
            || (*SDL_EventOK) (SDL_EventOKParam, &event)) {
            posted = 1;
            SDL_PushEvent(&event);
        }
    }
#endif /* !SDL_EVENTS_DISABLED */
    return (posted);
}

void
SDL_JoystickUpdate(void)
{
    int i;

    for (i = 0; SDL_joysticks[i]; ++i) {
        SDL_SYS_JoystickUpdate(SDL_joysticks[i]);
    }
}

int
SDL_JoystickEventState(int state)
{
#if SDL_EVENTS_DISABLED
    return SDL_IGNORE;
#else
    const Uint8 event_list[] = {
        SDL_JOYAXISMOTION, SDL_JOYBALLMOTION, SDL_JOYHATMOTION,
        SDL_JOYBUTTONDOWN, SDL_JOYBUTTONUP,
    };
    unsigned int i;

    switch (state) {
    case SDL_QUERY:
        state = SDL_IGNORE;
        for (i = 0; i < SDL_arraysize(event_list); ++i) {
            state = SDL_EventState(event_list[i], SDL_QUERY);
            if (state == SDL_ENABLE) {
                break;
            }
        }
        break;
    default:
        for (i = 0; i < SDL_arraysize(event_list); ++i) {
            SDL_EventState(event_list[i], state);
        }
        break;
    }
    return (state);
#endif /* SDL_EVENTS_DISABLED */
}

/* vi: set ts=4 sw=4 expandtab: */