view test/testjoystick.c @ 2675:5e4274591163 gsoc2008_nds

Started minor changes to the coordinate system used by the touchscreen API as discussed on the mailing list. Also beginning to separate the 'Pressed' and 'Moved' event handling on the private level.
author Darren Alton <dalton@stevens.edu>
date Sun, 29 Jun 2008 21:32:31 +0000
parents 6280c111ee80
children 450a9bf50c37 f55c87ae336b
line wrap: on
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/* Simple program to test the SDL joystick routines */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "SDL.h"

#define SCREEN_WIDTH	640
#define SCREEN_HEIGHT	480

void
WatchJoystick(SDL_Joystick * joystick)
{
    SDL_Surface *screen;
    const char *name;
    int i, done;
    SDL_Event event;
    int x, y, draw;
    SDL_Rect axis_area[6][2];

    /* Set a video mode to display joystick axis position */
    screen = SDL_SetVideoMode(SCREEN_WIDTH, SCREEN_HEIGHT, 16, 0);
    if (screen == NULL) {
        fprintf(stderr, "Couldn't set video mode: %s\n", SDL_GetError());
        return;
    }

    /* Print info about the joystick we are watching */
    name = SDL_JoystickName(SDL_JoystickIndex(joystick));
    printf("Watching joystick %d: (%s)\n", SDL_JoystickIndex(joystick),
           name ? name : "Unknown Joystick");
    printf("Joystick has %d axes, %d hats, %d balls, and %d buttons\n",
           SDL_JoystickNumAxes(joystick), SDL_JoystickNumHats(joystick),
           SDL_JoystickNumBalls(joystick), SDL_JoystickNumButtons(joystick));

    /* Initialize drawing rectangles */
    memset(axis_area, 0, (sizeof axis_area));
    draw = 0;

    /* Loop, getting joystick events! */
    done = 0;
    while (!done) {
        while (SDL_PollEvent(&event)) {
            switch (event.type) {
            case SDL_JOYAXISMOTION:
                printf("Joystick %d axis %d value: %d\n",
                       event.jaxis.which,
                       event.jaxis.axis, event.jaxis.value);
                break;
            case SDL_JOYHATMOTION:
                printf("Joystick %d hat %d value:",
                       event.jhat.which, event.jhat.hat);
                if (event.jhat.value == SDL_HAT_CENTERED)
                    printf(" centered");
                if (event.jhat.value & SDL_HAT_UP)
                    printf(" up");
                if (event.jhat.value & SDL_HAT_RIGHT)
                    printf(" right");
                if (event.jhat.value & SDL_HAT_DOWN)
                    printf(" down");
                if (event.jhat.value & SDL_HAT_LEFT)
                    printf(" left");
                printf("\n");
                break;
            case SDL_JOYBALLMOTION:
                printf("Joystick %d ball %d delta: (%d,%d)\n",
                       event.jball.which,
                       event.jball.ball, event.jball.xrel, event.jball.yrel);
                break;
            case SDL_JOYBUTTONDOWN:
                printf("Joystick %d button %d down\n",
                       event.jbutton.which, event.jbutton.button);
                break;
            case SDL_JOYBUTTONUP:
                printf("Joystick %d button %d up\n",
                       event.jbutton.which, event.jbutton.button);
                break;
            case SDL_KEYDOWN:
                if (event.key.keysym.sym != SDLK_ESCAPE) {
                    break;
                }
                /* Fall through to signal quit */
            case SDL_QUIT:
                done = 1;
                break;
            default:
                break;
            }
        }
        /* Update visual joystick state */
        for (i = 0; i < SDL_JoystickNumButtons(joystick); ++i) {
            SDL_Rect area;

            area.x = i * 34;
            area.y = SCREEN_HEIGHT - 34;
            area.w = 32;
            area.h = 32;
            if (SDL_JoystickGetButton(joystick, i) == SDL_PRESSED) {
                SDL_FillRect(screen, &area, 0xFFFF);
            } else {
                SDL_FillRect(screen, &area, 0x0000);
            }
            SDL_UpdateRects(screen, 1, &area);
        }

        for (i = 0;
             i < SDL_JoystickNumAxes(joystick) / 2
             && i < SDL_arraysize(axis_area); ++i) {
            /* Erase previous axes */
            SDL_FillRect(screen, &axis_area[i][draw], 0x0000);

            /* Draw the X/Y axis */
            draw = !draw;
            x = (((int) SDL_JoystickGetAxis(joystick, i * 2 + 0)) + 32768);
            x *= SCREEN_WIDTH;
            x /= 65535;
            if (x < 0) {
                x = 0;
            } else if (x > (SCREEN_WIDTH - 16)) {
                x = SCREEN_WIDTH - 16;
            }
            y = (((int) SDL_JoystickGetAxis(joystick, i * 2 + 1)) + 32768);
            y *= SCREEN_HEIGHT;
            y /= 65535;
            if (y < 0) {
                y = 0;
            } else if (y > (SCREEN_HEIGHT - 16)) {
                y = SCREEN_HEIGHT - 16;
            }
            axis_area[i][draw].x = (Sint16) x;
            axis_area[i][draw].y = (Sint16) y;
            axis_area[i][draw].w = 16;
            axis_area[i][draw].h = 16;
            SDL_FillRect(screen, &axis_area[i][draw], 0xFFFF);

            SDL_UpdateRects(screen, 2, axis_area[i]);
        }
    }
}

int
main(int argc, char *argv[])
{
    const char *name;
    int i;
    SDL_Joystick *joystick;

    /* Initialize SDL (Note: video is required to start event loop) */
    if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK) < 0) {
        fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());
        exit(1);
    }

    /* Print information about the joysticks */
    printf("There are %d joysticks attached\n", SDL_NumJoysticks());
    for (i = 0; i < SDL_NumJoysticks(); ++i) {
        name = SDL_JoystickName(i);
        printf("Joystick %d: %s\n", i, name ? name : "Unknown Joystick");
        joystick = SDL_JoystickOpen(i);
        if (joystick == NULL) {
            fprintf(stderr, "SDL_JoystickOpen(%d) failed: %s\n", i,
                    SDL_GetError());
        } else {
            printf("       axes: %d\n", SDL_JoystickNumAxes(joystick));
            printf("      balls: %d\n", SDL_JoystickNumBalls(joystick));
            printf("       hats: %d\n", SDL_JoystickNumHats(joystick));
            printf("    buttons: %d\n", SDL_JoystickNumButtons(joystick));
            SDL_JoystickClose(joystick);
        }
    }

    if (argv[1]) {
        joystick = SDL_JoystickOpen(atoi(argv[1]));
        if (joystick == NULL) {
            printf("Couldn't open joystick %d: %s\n", atoi(argv[1]),
                   SDL_GetError());
        } else {
            WatchJoystick(joystick);
            SDL_JoystickClose(joystick);
        }
    }
    SDL_QuitSubSystem(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK);

    return (0);
}