Add first version of joystick test program.

Makefile

@@ -0,0 +1,7 @@
+
+CFLAGS = $(shell sdl-config --cflags)
+LDFLAGS = $(shell sdl-config --libs)
+
+joytest : joytest.c
+	$(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
+

joytest.c

@@ -0,0 +1,151 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "SDL.h"
+
+void ProcessAxisMotion(SDL_Event *ev)
+{
+    static int lastjoy = -1, lastaxis, lastdirection;
+    int direction;
+
+    direction = ev->jaxis.value > 0;
+
+    if (ev->jaxis.which == lastjoy && ev->jaxis.axis == lastaxis
+     && direction == lastdirection)
+    {
+        return;
+    }
+
+    // Only print a message when pushed to the extreme
+    if (abs(ev->jaxis.value) < 30000)
+    {
+        return;
+    }
+
+    printf("%i: Axis %i pushed to extreme: %i\n",
+           ev->jaxis.which, ev->jaxis.axis, ev->jaxis.value);
+
+    lastjoy = ev->jaxis.which;
+    lastaxis = ev->jaxis.axis;
+    lastdirection = direction;
+}
+
+void ProcessBallMotion(SDL_Event *ev)
+{
+    printf("%i: Ball %i motion: %i, %i\n",
+           ev->jball.which, ev->jball.ball, ev->jball.xrel, ev->jball.yrel);
+}
+
+char *HatDirection(int value)
+{
+    switch (value)
+    {
+        case SDL_HAT_UP:
+            return "UP";
+        case SDL_HAT_DOWN:
+            return "DOWN";
+        case SDL_HAT_LEFT:
+            return "LEFT";
+        case SDL_HAT_RIGHT:
+            return "RIGHT";
+        default:
+            return NULL;
+    }
+}
+
+void ProcessHatMotion(SDL_Event *ev)
+{
+    char *dirstr;
+
+    dirstr = HatDirection(ev->jhat.value);
+
+    if (dirstr != NULL)
+    {
+        printf("%i: Hat %i moved to %s", ev->jhat.which, ev->jhat.hat,
+               dirstr);
+    }
+}
+
+void ProcessButtonDown(SDL_Event *ev)
+{
+    printf("%i: Button %i pressed\n", ev->jbutton.which, ev->jbutton.button);
+}
+
+void StartJoysticks(void)
+{
+    SDL_Joystick *js;
+    int i;
+
+    // Open all joysticks.
+
+    printf("%i joysticks:\n", SDL_NumJoysticks());
+
+    for (i = 0 ; i < SDL_NumJoysticks(); ++i)
+    {
+        printf("\t#%i: '%s'\n", i, SDL_JoystickName(i));
+
+        js = SDL_JoystickOpen(i);
+        printf("\t\taxes: %i\n", SDL_JoystickNumAxes(js));
+        printf("\t\tbuttons: %i\n", SDL_JoystickNumButtons(js));
+        printf("\t\tballs: %i\n", SDL_JoystickNumBalls(js));
+        printf("\t\thats: %i\n", SDL_JoystickNumHats(js));
+    }
+}
+
+int main(int argc, char *argv[])
+{
+    SDL_Event ev;
+
+    SDL_Init(SDL_INIT_JOYSTICK|SDL_INIT_VIDEO);
+
+    if (SDL_NumJoysticks() == 0)
+    {
+        fprintf(stderr, "Found no joysticks to configure!\n");
+        return 1;
+    }
+
+    SDL_SetVideoMode(400, 200, 0, 0);
+    SDL_WM_SetCaption("Close this window to quit.", NULL);
+
+    StartJoysticks();
+
+    for (;;)
+    {
+        SDL_PumpEvents();
+        SDL_WaitEvent(&ev);
+        switch (ev.type)
+        {
+            case SDL_QUIT:
+                goto exitloop;
+
+            case SDL_KEYDOWN:
+                if (ev.key.keysym.sym == SDLK_ESCAPE)
+                {
+                    goto exitloop;
+                }
+                break;
+
+            case SDL_JOYAXISMOTION:
+                ProcessAxisMotion(&ev);
+                break;
+
+            case SDL_JOYBALLMOTION:
+                ProcessBallMotion(&ev);
+                break;
+
+            case SDL_JOYHATMOTION:
+                ProcessHatMotion(&ev);
+                break;
+
+            case SDL_JOYBUTTONDOWN:
+                ProcessButtonDown(&ev);
+                break;
+        }
+    }
+exitloop:
+
+    SDL_Quit();
+
+    return 0;
+}
+