Scroll wheel support

- All areas with scroll wheels can be scrolled using the scroll wheel if the mouse is in the area
- In addition, the terrain view is scrollable with the scroll wheel (hold Control for horizontal scrolling)
- The above applies in the game too, whenever the scroll arrows are visible

src/scenedit/scen.actions.cpp

@@ -59,7 +59,7 @@ cTown::cItem store_place_item;
 short flood_count = 0;
 
 rectangle terrain_rects[256],terrain_rect_base = {0,0,16,16},command_rects[21];
-
+extern rectangle terrain_buttons_rect;
 
 extern short cen_x, cen_y, cur_town;
 extern eScenMode overall_mode;
@@ -1515,6 +1515,30 @@ void handle_keystroke(sf::Event event) {
 	mouse_button_held = false;
 }
 
+bool handle_scroll(sf::Event& event) {
+	rectangle pal_rect = terrain_buttons_rect, right_area_rect = {0,0,RIGHT_AREA_HEIGHT,RIGHT_AREA_WIDTH};
+	right_area_rect.offset(RIGHT_AREA_UL_X, RIGHT_AREA_UL_Y);
+	pal_rect.offset(RIGHT_AREA_UL_X,RIGHT_AREA_UL_Y);
+	pal_rect.height() = 16 * 17 + 2;
+	fill_rect(mainPtr, right_area_rect, sf::Color::Magenta);
+	location pos(event.mouseWheel.x, event.mouseWheel.y);
+	int amount = event.mouseWheel.delta;
+	if(right_sbar->isVisible() && pos.in(right_area_rect)) {
+		right_sbar->setPosition(right_sbar->getPosition() - amount);
+		redraw_screen();
+	} else if(pal_sbar->isVisible() && pos.in(pal_rect)) {
+		pal_sbar->setPosition(pal_sbar->getPosition() - amount);
+		set_up_terrain_buttons(false);
+		redraw_screen();
+	} else if(overall_mode < MODE_MAIN_SCREEN && pos.in(world_screen)) {
+		if(sf::Keyboard::isKeyPressed(sf::Keyboard::LControl) || sf::Keyboard::isKeyPressed(sf::Keyboard::RControl))
+			cen_x -= amount;
+		else cen_y -= amount;
+		redraw_screen();
+	}
+	return true;
+}
+
 void shy_change_circle_terrain(location center,short radius,ter_num_t terrain_type,short probability) {
 	// prob is 0 - 20, 0 no, 20 always
 	location l;

src/scenedit/scen.actions.h

@@ -5,6 +5,7 @@ void flash_rect(rectangle to_flash);
 void swap_terrain();
 void set_new_terrain(ter_num_t selected_terrain);
 void handle_keystroke(sf::Event event);
+bool handle_scroll(sf::Event& event);
 void get_wandering_monst();
 void get_town_info();
 void get_sign_resource();

src/scenedit/scen.btnmg.cpp

@@ -16,7 +16,6 @@ extern rectangle right_sbar_rect;
 rectangle left_button[NLS];
 extern rectangle right_buttons[NRSONPAGE];
 rectangle right_scrollbar_rect;
-rectangle right_area_rect;
 extern short current_rs_top;
 
 bool left_buttons_active = 1,right_buttons_active = 0;

src/scenedit/scen.graphics.cpp

@@ -48,7 +48,6 @@ extern sf::Texture bg_gworld;
 extern rectangle left_button[NLS];
 extern rectangle right_buttons[NRSONPAGE];
 extern rectangle right_scrollbar_rect;
-extern rectangle right_area_rect;
 extern std::shared_ptr<cScrollbar> right_sbar, pal_sbar;
 
 extern bool left_buttons_active,right_buttons_active;

src/scenedit/scen.main.cpp

@@ -169,6 +169,10 @@ void Handle_One_Event() {
 			update_mouse_spot(loc(event.mouseMove.x,event.mouseMove.y));
 			break;
 			
+		case sf::Event::MouseWheelMoved:
+			handle_scroll(event);
+			break;
+			
 		case sf::Event::MouseButtonReleased:
 			mouse_button_held = false;
 			break;