Implement smooth scroll and smooth zoom

config.c

@@ -315,16 +315,18 @@ config_load_default(zathura_t* zathura)
   girara_shortcut_add(gsession, 0,                0,                  "zZ", sc_zoom,                    (mode),     ZOOM_SPECIFIC,          NULL);
 
 #define DEFAULT_MOUSE_EVENTS(mode) \
-  girara_mouse_event_add(gsession, 0, 0,                                   sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_UP,      UP,    NULL); \
-  girara_mouse_event_add(gsession, 0, 0,                                   sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_DOWN,    DOWN,  NULL); \
-  girara_mouse_event_add(gsession, 0, 0,                                   sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_LEFT,    LEFT,  NULL); \
-  girara_mouse_event_add(gsession, 0, 0,                                   sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_RIGHT,   RIGHT, NULL); \
+  girara_mouse_event_add(gsession, 0, 0,                                   sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_UP,            UP,            NULL); \
+  girara_mouse_event_add(gsession, 0, 0,                                   sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_DOWN,          DOWN,          NULL); \
+  girara_mouse_event_add(gsession, 0, 0,                                   sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_LEFT,          LEFT,          NULL); \
+  girara_mouse_event_add(gsession, 0, 0,                                   sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_RIGHT,         RIGHT,         NULL); \
+  girara_mouse_event_add(gsession, 0, 0,                                   sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_BIDIRECTIONAL, BIDIRECTIONAL, NULL); \
 \
   girara_mouse_event_add(gsession, GDK_SHIFT_MASK, 0,                      sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_UP,      LEFT,  NULL); \
   girara_mouse_event_add(gsession, GDK_SHIFT_MASK, 0,                      sc_mouse_scroll, (mode),     GIRARA_EVENT_SCROLL_DOWN,    RIGHT, NULL); \
 \
-  girara_mouse_event_add(gsession, GDK_CONTROL_MASK, 0,                    sc_mouse_zoom,   (mode),     GIRARA_EVENT_SCROLL_UP,      UP,   NULL); \
-  girara_mouse_event_add(gsession, GDK_CONTROL_MASK, 0,                    sc_mouse_zoom,   (mode),     GIRARA_EVENT_SCROLL_DOWN,    DOWN, NULL); \
+  girara_mouse_event_add(gsession, GDK_CONTROL_MASK, 0,                    sc_mouse_zoom,   (mode),     GIRARA_EVENT_SCROLL_UP,            UP,            NULL); \
+  girara_mouse_event_add(gsession, GDK_CONTROL_MASK, 0,                    sc_mouse_zoom,   (mode),     GIRARA_EVENT_SCROLL_DOWN,          DOWN,          NULL); \
+  girara_mouse_event_add(gsession, GDK_CONTROL_MASK, 0,                    sc_mouse_zoom,   (mode),     GIRARA_EVENT_SCROLL_BIDIRECTIONAL, BIDIRECTIONAL, NULL); \
   girara_mouse_event_add(gsession, 0,                GIRARA_MOUSE_BUTTON2, sc_mouse_scroll, (mode),     GIRARA_EVENT_BUTTON_PRESS,   0,    NULL); \
   girara_mouse_event_add(gsession, GDK_BUTTON2_MASK, GIRARA_MOUSE_BUTTON2, sc_mouse_scroll, (mode),     GIRARA_EVENT_BUTTON_RELEASE, 0,    NULL); \
   girara_mouse_event_add(gsession, GDK_BUTTON2_MASK, 0,                    sc_mouse_scroll, (mode),     GIRARA_EVENT_MOTION_NOTIFY,  0,    NULL); \

shortcuts.c

@@ -285,6 +285,7 @@ sc_mouse_scroll(girara_session_t* session, girara_argument_t* argument, girara_e
     case GIRARA_EVENT_SCROLL_DOWN:
     case GIRARA_EVENT_SCROLL_LEFT:
     case GIRARA_EVENT_SCROLL_RIGHT:
+    case GIRARA_EVENT_SCROLL_BIDIRECTIONAL:
       return sc_scroll(session, argument, NULL, t);
 
       /* drag */
@@ -339,6 +340,9 @@ sc_mouse_zoom(girara_session_t* session, girara_argument_t* argument, girara_eve
     case GIRARA_EVENT_SCROLL_DOWN:
       argument->n = ZOOM_OUT;
       break;
+    case GIRARA_EVENT_SCROLL_BIDIRECTIONAL:
+      argument->n = ZOOM_SMOOTH;
+      break;
     default:
       return false;
   }
@@ -589,6 +593,13 @@ sc_scroll(girara_session_t* session, girara_argument_t* argument,
     case RIGHT:
       pos_x += direction * t * scroll_hstep / (double)doc_width;
       break;
+
+    case BIDIRECTIONAL: {
+      double* movement = (double*)argument->data;
+      pos_x += movement[0] * t * scroll_hstep / (double)doc_width;
+      pos_y += movement[1] * t * scroll_step / (double)doc_height;
+      break;
+    }
   }
 
   /* handle boundaries */
@@ -1367,6 +1378,9 @@ sc_zoom(girara_session_t* session, girara_argument_t* argument, girara_event_t*
     } else {
       zathura_document_set_scale(zathura->document, t / 100.0);
     }
+  } else if (argument->n == ZOOM_SMOOTH) {
+     double dy = ((double*)argument->data)[1];
+     zathura_document_set_scale(zathura->document, old_zoom + zoom_step * dy);
   } else {
     zathura_document_set_scale(zathura->document, 1.0);
   }

zathura.h

@@ -60,7 +60,9 @@ enum {
   ROTATE_CW,
   ROTATE_CCW,
   PAGE_BOTTOM,
-  PAGE_TOP
+  PAGE_TOP,
+  BIDIRECTIONAL,
+  ZOOM_SMOOTH
 };
 
 /* unspecified page number */