Create bigger rooms with a single click

[Loobinex]

When placing a room type, the player can use LSHIFT, LCTRL, and the NUMKEYS to place multiple room slabs with a single click. The bounding box displays this multi-slab room, to show the player the slabs that the current room type will be placed in.

These new features are described in the following sections:

• Room Detection mode: Overview
• Fixed Room Size mode: Overview
• Bridge Painting mode: Overview
• Room Detection mode: Brief Technical Description

Summary of code changes in this Pull Request:

Code additions for the "find best room algorithm" (list to be completed):

• Created slab_room_detection.c and slab_room_detection.h. These contain the algorithm for finding the "best" room, based on the current cursor position.
• ...

Function changes/additions to support "box rooms" and "fancy rooms":

• _lots of stuff in slabdata.c
• render_room is used publicly to enable the drawing of a "fancy" bounding box. A Fancy bounding box is only drawn around the slabs that are in the room, and can be any shape.
• create_map_volume_box() and create_frontview_map_volume_box() updated to work with varying sizes of boxes.
• create_accurate_map_volume_box() and create_accurate_frontview_map_volume_box() created to allow for drawing "fancy" bounding boxes.
• draw_frontview_engine() and draw_view() now detect if the current room is a fancy room or a box room, and call the correct volume box function accordingly.
• tag_cursor_blocks_place_room() can now use a room of a chosen width/height, or a "fancy" room, and set up the bounding box correctly.
• tag_cursor_blocks_sell_area() can now use a room of a chosen width/height, and set up the bounding box correctly.
• process_dungeon_control_packet_dungeon_build_room() now sets the width/height of a "room" based on what input the player uses. get_biggest_room() is called from here, which runs the "find best room algorithm".
• process_dungeon_control_packet_sell_operation() now sets the width/height of a "room" based on what input the player uses.
• gui_area_big_room_button() uses the number of slabs in a room to display the correct total price.
• player_build_room_at() now uses the total room cost, rather the cost of a single slab.

Additional supporting function changes:

• floor_height_for_volume_box() moved from thing_traps.c to engine_render.c, so that it can be used by other scripts. Duplicate code was removed from tag_cursor_blocks_sell_area(), tag_cursor_blocks_place_door(), and tag_cursor_blocks_place_room() in main.cpp and replaced with a call to floor_height_for_volume_box().
• create_line_element() now contains a check for space in the poly pool, this is so the check doesn't have to be done outside of this function.

DK variable name changes:

• field_2 of struct PlayerInfo renamed to boxsize. This is the number of slabs in a room/box.
• temp_cluedo_mode described (should maybe be renamed?) - 4891d95.
• field_13 of struct MapVolumeBox renamed to floor_height_z this stores the height of a slab's lowest point. floor_height_for_volume_box() is used to set a height of 0 for water/lava, 1 for floors, and 5 for walls. If cluedo mode is used a wall will have a height of 2.
• Can map_volume_box.field_17 be renamed too? To something like box_length, box_diameter, box_longest_side etc

[eddebaby]

This follows from #161

[eddebaby]

Room Detection mode: Overview

• Hold LEFT SHIFT on the keyboard, after selecting a room type to place, to use Room Detection mode.
• A "room" of a defined width and height can be detected/chosen when placing any room type, except bridges.
• Its boundaries are indicated by an appropriate bounding box around the cursor.
• Room Detection is based on the position of the cursor, if the correct room is not detected, move the cursor towards the centre of the room you want to fill.
• When the player clicks, the chosen room type is placed on all of the indicated tiles.
• If the player doesn't have enough funds to place all of the slabs, the bounding box is red, and the slabs will not be placed when the player clicks.

[eddebaby]

Room Detection mode: Brief Technical Description

Rooms can either be:

• A "box" - i.e. they are square/rectangular, and all of the tiles within the rooms area are valid locations for the selected room type. It only needs to be described by a centre and a width/height - the left,right,top,bottom extents are then derived from these.
• A "fancy room" - this is any room that contains tiles that are invalid locations for the selected room type. Fancy rooms are expressed as a 2D array of booleans, where a value of true means that the current tile is a valid location for the selected room type, and false means the opposite.

_Graphical representation of a "fancy room", a 2D array of booleans, e.g. TbBool best_room[][]:_

• a value of 1 is a slab that is part of the room ("room" tiles)
• a value of 0 is a slab that is not part of the room ("air" tiles)
• the green border represents the bounding box that will be drawn around the room

Drawing bounding boxes:

• create_map_volume_box() / create_frontview_map_volume_box() have been expanded, and are used to draw the bound boxes for box rooms. They use the width and height of the room.
• create_accurate_map_volume_box() / create_accurate_frontview_map_volume_box() are new, and are used to draw the bound boxes for fancy rooms. They use the 2D array that describes the room. The correct edges are drawn, based on the presence of surrounding false ("air") tiles, so that the accurate outline of the room is displayed.

Slab validity:

• Both the Room Detection and Fixed Room Size modes validate the slabs that are within the room. can_build_room_at_slab() is used to make sure nothing would block the placing of the chosen room type at a particular slab.
• Any slabs that are found to be not valid by can_build_room_at_slab(), will be set to false in the 2D array. They will then be excluded from the bounding box, and there will be no attempt to place a room slab at these invalid locations.

Finding the biggest room:

• Starting at the current cursor position, and working outwards from there, each tile is considered as the centre of a potential room.
  • For each room centre, the biggest possible box room (largest area) is found (by testing the validity of the tiles for placing the current room type). At this point in time a box room can contain invalid tiles, if this option is set by the player.
  • This cursor must fall within the extents of the room. This ensures it is a room that the player wants, rather than a seemingly random one somewhere else on the screen.
  • If a corridor (a room that is too wide/tall) is found, then the biggest square room is returned instead.
• This search is repeated 5 times, each time search for wider/taller rooms, these rooms are composited together to produce the final room. There is also an additional check for a perfectly square room, that helps to fill it awkwardly shaped rooms.
• A composite room will ignore any found corridors, and if a composite room is found, it will take precedence over any "corridor room".

[eddebaby]

Fixed Room Size mode: Overview

• Hold LEFT CONTROL on the keyboard, after selecting a room type to place, to use Fixed Room Size mode.
• By default a 5x5 room, centred at the cursor, will be used. If the player scrolls the mouse wheel up and down, they can increase/decrease the size of the square room between 1x1 and 9x9 tiles.
• The player can also hold a numkey between 2 and 9 to select a square room of that size - e.g. hold numkey 5 for a 5x5 room.
• Only the tiles that are able to have the chosen room type placed on them will be surrounded by a green bounding box.
• When the player clicks, the chosen room type is placed on all of the indicated tiles.
• If the player doesn't have enough funds to place all of the slabs, the bounding box is red, and the slabs will not be placed when the player clicks.
• Can be used with any room type, except for Bridges.

[eddebaby]

Bridge Painting mode: Overview

• Hold LEFT CONTROL or LEFT SHIFT on the keyboard, after selecting the Bridge room type, to use Bridge Painting mode.
• Hold the left mouse button to continuously place Bridges. Move the mouse cursor around to "paint" a long bridge.

[eddebaby]

Reorganisation:

• new roomspace scripts(roomspace.c/.h and roomspace_detection.c/.h) house the new functionality for dealing with roomspaces.
• engine_render.c contains the new fancy boundboxes, and improvements to the boundbox rendering in frontview
• All other scripts (apart from the new roomspace ones) either now call functions from the roomspace scripts, or have been tidied up

Needed work pushed to version 2:

• roomspace.c needs some improvements, especially for handling the user input
• roomspace_detection.c could be completely reworked, as the existing algorithm is slow, and not ideal. However, it works well. If it is to be kept, the code layout should be refined.
• more new features

[Loobinex]

1) Boundbox colors are not right for selling. It's always colored for the slab beneath the cursor, so it could be a red boundbox but you still sell when clicking if there's other tiles below. 2) Ctrl+Scroll still both changes the size of the boundbox AND scrolls the objective message at the same time.