add relative mouse movement

diff --git a/in_sdl.c b/in_sdl.c
index 148a09f..64df96d 100644 (file)
--- a/in_sdl.c
+++ b/in_sdl.c
@@ -400,8 +400,11 @@ static int collect_events(struct in_sdl_state *state, int *one_kc, int *one_down
                                                        if (event->button.state == SDL_PRESSED)
                                                                state->mevent.motion.state |= mask;
                                                        else    state->mevent.motion.state &= ~mask;
-                                               } else if (event->type == SDL_MOUSEMOTION)
+                                               } else if (event->type == SDL_MOUSEMOTION) {
+                                                       event->motion.xrel += state->mevent.motion.xrel;
+                                                       event->motion.yrel += state->mevent.motion.yrel;
                                                        state->mevent = *event;
+                                               }
                                                else if (ext_event_handler != NULL)
                                                        ext_event_handler(event);
                                                break;
@@ -494,16 +497,30 @@ static int in_sdl_update_analog(void *drv_data, int axis_id, int *result)
        struct in_sdl_state *state = drv_data;
        int max;
 
-       if (axis_id >= 2 || axis_id < -1)
-               return -1;
-
        *result = 0;
-       if (axis_id < 0)
-               *result = state->mevent.motion.state;
-       else if (axis_id && (max = state->revent.resize.h))
-               *result = state->mevent.motion.y * 2*1024/max - 1024;
-       else if (!axis_id && (max = state->revent.resize.w))
-               *result = state->mevent.motion.x * 2*1024/max - 1024;
+
+       switch (axis_id) {
+       // absolute position, clipped at the window/screen border
+       case 0: if ((max = state->revent.resize.w))
+                       *result = state->mevent.motion.x * 2*1024/max - 1024;
+               break;
+       case 1: if ((max = state->revent.resize.h))
+                       *result = state->mevent.motion.y * 2*1024/max - 1024;
+               break;
+       // relative mouse movements since last query
+       case 2: if ((max = state->revent.resize.w))
+                       *result = state->mevent.motion.xrel * 2*1024/max;
+               state->mevent.motion.xrel = 0;
+               break;
+       case 3: if ((max = state->revent.resize.h))
+                       *result = state->mevent.motion.yrel * 2*1024/max;
+               state->mevent.motion.yrel = 0;
+               break;
+       // buttons
+       case -1: *result = state->mevent.motion.state;
+               break;
+       default: return -1;
+       }
 
        return 0;
 }