Keep cursor on original spot(of tile) clicked while dragging

diff --git a/kub.c b/kub.c
index d878ecdc9acc16abf1d8fff1d1c30a61ed518b61..6a2a3a5903e7ca4a51590430747e1bd5a325ca16 100644 (file)
--- a/kub.c
+++ b/kub.c
@@ -92,6 +92,7 @@ typedef struct game {
     RsvgHandle *blanktile;
 
     int current_tile;
+    int diff_x, diff_y;
 } game_t;
 
 static void
@@ -390,6 +391,11 @@ static void hand_print(game_t *game)
     }
 }
 
+/* static void hand_draw(game_t *game) */
+/* { */
+    
+/* } */
+
 static void game_init(game_t *game)
 {
     int i;
@@ -412,6 +418,7 @@ static void game_init(game_t *game)
        FATAL_ERROR (error->message);
 
     game->current_tile = game->deck.num_tiles - 1;
+    game->diff_x = game->diff_y = 0;
 }
 
 static gboolean on_expose_event (GtkWidget *widget, GdkEventExpose *event, game_t *game)
@@ -444,8 +451,11 @@ static gboolean on_button_press_event (GtkWidget *widget, GdkEventButton *event,
        tile_y = game->deck.tiles[i].y;
        if (event->x >= tile_x && event->x <= (tile_x + TILE_WIDTH) &&
            event->y >= tile_y && event->y <= (tile_y + TILE_HEIGHT) )
-
+       {
            game->current_tile = i;
+           game->diff_x = event->x - tile_x;
+           game->diff_y = event->y - tile_y;
+       }
     }
 
     return TRUE;
@@ -470,8 +480,8 @@ static gboolean on_button_motion_event (GtkWidget *widget, GdkEventMotion *event
     gtk_widget_queue_draw_area (widget, tile->x - 1, tile->y - 1, TILE_WIDTH + 1, TILE_HEIGHT + 2);
     
     /* Then, move the tile */
-    tile->x = event->x;
-    tile->y = event->y;
+    tile->x = event->x - game->diff_x;
+    tile->y = event->y - game->diff_y;
     
     /* Finally, invalidate the region where the tile is now. */
     gtk_widget_queue_draw_area (widget, tile->x - 1, tile->y - 1, TILE_WIDTH + 1, TILE_HEIGHT + 2);