Special Variables

Some variables have special meaning to the interpreter:

Var	Name in defines.txt	Description
v0	room_no	Number of the current room
v1	prev_room_no	Number of the previous room
v2	ego_edge_code	Which edge of the screen ego is touching 0 = not touching edge 1 = horizon 2 = right edge 3 = bottom edge 4 = left edge
v3	score	Current score
v4	object_touching_edge	Number of an object other than ego that is touching the edge
v5	object_edge_code	See ego_edge_code
v6	ego_dir	Direction of ego's motion (see Moving objects for a list of directions)
v7	max_score	Maximum score
v8	free_memory	The number of 256-byte lots of free memory available for resources
v9	unknown_word_no	If the player has entered an unknown word, this is set to the number of that word (i.e., 2 if it's the second word entered). Otherwise, this is 0.
v10	cycle_delay	Delay between interpreter cycles, in 1/20 second increments.
v11	clock_seconds	Number of seconds on the interpreter's clock (the clock is reset when the game starts)
v12	clock_minutes	Number of minutes on the interpreter's clock
v13	clock_hours	Number of hours on the interpreter's clock
v14	clock_days	Number of days on the interpreter's clock
v15	joystick_sensitivity	Sensitivity of the joystick
v16	ego_view_no	Number of the view assigned to ego
v17	error_code	What type of error has occurred
v18	error_information	Extra information about the error
v19	key_pressed	The ASCII code of the key that has just been pressed, if any
v20	computer_type	Type of computer (0 = PC)
v21	window_close_time	Number of half-seconds to wait before closing a window (if 0, the window remains on screen until the user presses a key)
v22	sound_type	Number of sound channels (PC = 1, Tandy = 3)
v23	sound_volume	Volume of the sound (0 = loudest, 15 = quietest)
v24	(not defined)	Specifies the maximum number of characters that the player may enter on the input line. Defaults to 41.
v25	selected_inventory_item	If the player has selected an inventory item from the inventory screen, this is set to the number of that item (or 255 if ESC was pressed)
v26	video_mode	Video mode: 0 = CGA (black-cyan-magenta-white CGA palette)(see note) 1 = RGB (blue-yellow-red--green CGA palette) 2 = Hercules 3 = EGA 4 = MCGA Note: In real CGA with composite monitor, the game displays 160x200 with 16 color but the texts are weird. It's more like playing an AGI game on apple2. On CGA with color monitor, the game displays black and white. On EGA and more recent graphic card, CGA displays black-cyan-magenta-white CGA palette.

See also

• Special flags
• Variable

Sources

• AGI Studio help file

Data types

• Data types
  • Numbers
  • Variables
    • Special variables
  • Flags
    • Special flags
  • Messages
  • Animated objects
  • Inventory items
  • Strings
  • Words
  • Controllers