jetpac: Routines

Address	Description
6000	PC starts here, after game load.
6064	Reset the screen to its default state.
6083	Initialises a new level.
6094	Initialise the level.
60a7	Reset all rocket module states to their defaults.
60b7	End of turn for the current player.
6144	Swap current/inactive player/rocket states.
6174	Initialise player for new turn.
6197	Flash 1UP or 2UP score label for active player.
61a0	Set flash state for the 3-attributes of the score label.
61ad	Turn off flashing of 1UP or 2UP score label for active player.
61ba	Flash 2UP score label.
61bf	Game initialisation for first run.
61c9	Reset system and show menu screen.
61d5	Show menu screen and handle menu selection.
6234	Display the main menu items to the screen.
62ca	Write a single line of text on the main menu screen.
62da	Reset current and inactive player data on new game.
62fe	Start a new game.
6310	Reset stack pointer and enable interrupts before running main loop.
631c	The main game loop.
6334	Performs a main loop update jump.
6361	Update the high score.
63a3	Update Jet Fighter.
6456	Alien SFX when killed by collision.
6461	Jetman collects a collectible item.
648b	Drop a new collectible item.
64a0	Drop a gold bar collectible item.
64a4	Display a collectible sprite.
64ae	Sprite offset using colour attribute.
64b1	Get address for collectible sprite.
64bc	Drop a Plutonium collectible item.
64c2	Drop a chemical based item, flashing items radiation and plutonium.
64d7	Drop a random coloured collectible item.
64e8	Collision detection for collectible items / rocket modules.
6508	Increment Y position and draw sprite.
650e	Redraw a sprite.
6514	Gets collectible ID based on the current user level.
6523	Collect Rocket module or fuel pod.
6541	Carry a collected rocket module/fuel pod.
6565	Pick up and carry a rocket module/fuel pod.
65a8	Release new collectible item.
65db	Calculate column on which to drop a new collectible item/fuel pod.
65f9	Drop a new fuel pod collectible.
6624	Reset the Rocket modules state data ready for next level.
6629	Set objects as inactive.
6632	Animate the rocket flame sprites.
6690	Rocket ship is taking off.
66b4	Rocket ship is landing.
66d0	Update the rocket ship.
66fc	Update Rocket ship colour.
67b6	Rocket thruster SFX, and Jet Fighter explosions.
67c6	SFX for ship building.
67cc	SFX for collecting a fuel cell.
67d2	SFX for collecting an item, and when Jetman appears on-screen.
67d6	Play square wave sound.
67db	Play square wave sound, starting with silence.
67e7	SFX for Laser Fire.
67fd	Set the default explosion SFX params.
6814	Play Jetman death SFX.
681d	Play enemy death SFX.
6828	Plays the explosion sound effect.
6839	Sound has finished playing.
683e	Animate explosion after killing an alien.
685d	Enable animation, state false.
6868	Enable animation and reset frame count.
6874	Enable animation, state true.
687a	Animates the explosion sprites.
68e4	Frame rate limiter.
68f2	Copy the two sprites for an alien to the buffers.
692e	Frame update and disabled item drop.
6954	New actor: reset the modified code to original values.
6966	Reset the modified code within the current frame.
6971	Generate new game actor: alien, fuel, or collectible item.
6a35	Update Squidgy Alien.
6ab8	Update UFO alien -- this alien is a chaser!
6beb	Add points for UFO kill.
6bf1	When alien was killed by laser fire, reset anim state, set explosion SFX params. Used by the routine at 6a35.
6bf8	Update Sphere alien.
6cb0	Update Actor direction.
6cbe	Update crossed space ship.
6d43	Draw an alien sprite to the screen.
6d59	Add score for crossed space ship kill.
6d5c	Alien Killed SFX #2.
6d67	Change alien direction flag to up, and other updates.
6d9c	Update the meteor.
6de9	Alien Collision.
6e1b	Fire a laser beam.
6e66	Reads 2 bytes of pixel data from a sprite.
6e7c	Reverse all bits in Accumulator.
6e87	Flip byte pair of an alien sprite so it faces opposite direction.
6ea5	Write all sprite pixel bytes to buffer.
6ec2	Copy Rocket sprites for current level to the buffers.
6eef	Initialise rocket build state for new level.
6f0b	Copy Rocket sprite pixel data to the buffer.
6f16	Set the rocket building state on Jetman.
6f20	Set rocket module state that Jetman was carrying.
6f23	Get address to sprite pixel data then copy to the buffer.
6f2a	Copies the sprite pixel data to a buffer.
6f5a	Create new laser beam.
6f70	Initialise laser beam slot, and draw graphics.
6f86	Draw laser beam.
6fb6	Shoots a laser beam to the right.
6fc5	Animate a laser beam.
706d	Display the remaining player lives in the status bar.
70ac	Gets the remaining lives for player 1.
70b2	Reads the current player lives.
70b6	Reads inactive player lives.
70ba	Gets the remaining lives for player 2.
70c2	Add points to the active player's score.
70e5	Updates display to show player 1 score.
70ed	Updates display to show player 2 score.
70f5	Updates display to show high score.
70fb	Display a score.
7115	Display an ASCII character from the Font.
7124	Characters are 8 rows of pixels.
7126	Draw the pixels for an ASCII character on screen
7134	Display string (with colour) on the screen.
7140	Write a list of ASCII characters to the screen.
7151	Write an EOL character to the screen.
715a	Displays score labels at top of screen.
7180	Clears the entire ZX Spectrum display file.
7185	Clear memory block with null.
7187	Fill a memory block with a byte value.
718e	Clears the entire ZX Spectrum attribute file.
7197	Colourize a sprite.
71d6	Convert a Y,X pixel coordinate to an ATTRIBUTE_FILE address.
71ec	Generic jump routine for finding actor pos/dir.
71ef	Get location of Actor.
71f2	Get sprite position and dimensions.
7200	Increment DE to beginning of next sprite header.
7204	Find actor sprite address and update actor.
7207	Update actor state.
7226	Update Actor X/Y positions.
7232	Now update and erase the actor.
7239	Erase an actor sprite - after an it's been moved.
7263	Find animation sprite position and erase its pixels.
7268	Find Actor position, then erase its sprite.
726d	Find an Actor and destroy it.
7270	Erase a destroyed Actor.
727d	Unused?
7280	Erase an animation sprite.
7289	Find position and direction of an Actor.
7292	Get actor sprite address.
72ab	Move an actor's sprite to it's current position.
72b6	Calculate screen address one pixel above current position.
72d0	Convert a Y,X pixel coordinate to a DISPLAY_FILE address.
72ef	Copy actor position/direction values to Actor.
7302	Joystick Input (Interface 2)
7309	Read input from the keyboard port.
733f	Check if fire button is pressed.
735e	Check if thrust (up) button is pressed.
737d	Game play starts, or prepare new turn, or check Jetman thrust input.
739e	Airborne Jetman update.
73c3	Increase Jetman horizontal speed.
73d1	Update Jetman X speed with new value.
73d6	Set Jetman X speed to the max flying speed.
73da	Fly Jetman horizontally.
73f1	Apply gravity to Jetman if no thrust button detected.
7412	Check if Jetman is moving falling downward.
7425	Increase Jetman vertical speed.
7433	Update Jetman vertical speed with new value.
7438	Set Jetman vertical speed to zero.
743e	Check joystick input for FIRE or THRUST.
7448	Set Jetman vertical speed to maximum.
744c	Fly Jetman vertically.
7463	Check vertical position while in mid-flight.
7473	Jetman flight collision detection.
7492	Redraw Jetman sprite on the screen.
74a1	Jetman hits the underneath of a platform.
74a7	Jetman lands on a platform.
74bf	Reset Jetman movement direction.
74c5	Jetman hits the top of the screen.
74d5	Jetman is falling.
74e0	Flip vertical direction Jetman is flying.
74fa	Decrease Jetman X position.
7501	Jetman THRUST-LEFT input.
750c	Flip Jetman left/right flying direction.
7526	Move Jetman up: decrease Y position.
752d	Calculate new Jetman horizontal speed.
753c	Jetman walking.
75d1	Related to horizontal platform collision detection - possibly flipping between sprite X position collision and Jetman direction collision...needs more work!
75e8	Jetman/platform collision detection.
75ed	Horizontal platform collision detection for Jetman/Alien.
75fc	Vertical platform collision detection for Jetman/Aliens.
7638	Displays platforms on screen.
76a6	Draws the pixels for a platform sprite to the screen.
7705	Erase sprite pixels when actor/sprite moves.
7747	EXX then update Actor.
7748	Update Actor height related values.
775b	Update Actor sprite height, then mask the sprite.