Add joystick input

src/sdl.c

@@ -21,8 +21,6 @@ float x = 0, y = 0, z = 0;
 static Uint32 drive_timer_handler(Uint32 interval, void* param) {
     robot_drive((Robot)param, x, y, z);
     robot_aim((Robot)param, pitch, yaw);
-    yaw *= 0.80;
-    pitch *= 0.80;
     return 75;
 }
 static Uint32 heartbeat_timer_handler(Uint32 interval, void* param) {
@@ -31,10 +29,15 @@ static Uint32 heartbeat_timer_handler(Uint32 interval, void* param) {
 }
 
 int main(int argc, char* argv[]) {
-    if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_GAMECONTROLLER) < 0) {
+    if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK) < 0) {
         fprintf(stderr, "%s", SDL_GetError());
         return 1;
     }
+    printf("Detected %d joysticks\n", SDL_NumJoysticks());
+    SDL_Joystick* joystick = NULL;
+    if(SDL_NumJoysticks() > 0) {
+        joystick = SDL_JoystickOpen(0);
+    }
     SDL_Window* win = SDL_CreateWindow(
 		    "Robomaster",
 		    SDL_WINDOWPOS_UNDEFINED,
@@ -94,6 +97,28 @@ int main(int argc, char* argv[]) {
                     yaw = (float)event.motion.xrel;
                     pitch = (float)event.motion.yrel;
                     break;
+                case SDL_JOYAXISMOTION:
+                    switch(event.jaxis.axis) {
+                        case 0:
+                            x = (float)event.jaxis.value / 32767;
+                            break;
+                        case 1:
+                            y = (float)event.jaxis.value / 32767;
+                            break;
+                        case 4:
+                            z = (float)event.jaxis.value / 32767 / 2;
+                            break;
+                        case 2:
+                            yaw = (float)event.jaxis.value / 32767;
+                            break;
+                        case 3:
+                            pitch = (float)event.jaxis.value / 32767;
+                            break;
+                        default:
+                            printf("axis: %d\n", event.jaxis.axis);
+                            break;
+                    }
+                    break;
                 case SDL_WINDOWEVENT:
                     if(event.window.event != SDL_WINDOWEVENT_CLOSE) break;
                 case SDL_QUIT:
@@ -103,6 +128,7 @@ int main(int argc, char* argv[]) {
 	    }
     }
 
+    SDL_JoystickClose(joystick);
     SDL_Quit();
     return 0;
 }