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main
...
hud-update
356
old_readme.md
356
old_readme.md
@ -1,356 +0,0 @@
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This file contains text that used to be in the cartridge itself, but
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I'm getting increasingly anxious about cartridge space so I'm moving
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it out ot a separate file.
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---
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main loop sequence
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==================
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1. level_frame
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2. events
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3. merge new_events into events
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4. update bg intangibles
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5. move ships (player first)
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6. move bullets (player first)
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7. calculate collisions
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1. pship on eship
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2. ebullet on pship
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3. pbullet on eship
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8. update fg intangibles
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9. check for end of level
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draw order
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----------
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bottom to top:
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1. intangibles_bg
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2. player bullets
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3. player ships
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4. enemy ships
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5. enemy bullets
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6. intangibles_fg
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notes
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-----
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intangibles_fg move()s after
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all collisions and other moves
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are processed. if an intangible
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is added to the list as a result
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of a collision or move, it will
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itself be move()d before it is
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drawn.
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data-driven items
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=================
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guns and bullets both allow the
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most common behaviors to be
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expressed with data alone.
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ships only need a movement
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algorithm expressed.
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guns
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----
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* t - metatable for bullet type.
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fired once in the bullet's
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default direction per shot.
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* enemy - if true, fired bullets
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are flagged as enemy bullets.
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* icon - sprite index of an
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8x8 sprite to display in the
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hud when the player has this
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gun. default is 20, a generic
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crosshair bullseye thing.
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* cooldown - min frames between
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shots.
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* ammo, maxammo - permitted
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number of shots. 0 is empty
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and unfireable. maxammo = 0
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will cause a divide by zero
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so don't do that. if nil,
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ammo is infinite.
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default guns manage ammo and
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cooldown in shoot, then call
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actually_shoot to create the
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projectile. override only
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actually_shoot to change
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projectile logic while keeping
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cooldown and ammo logic.
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bullets
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-------
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* dx, dy - movement per frame.
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player bullets use -dy
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instead.
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* enemyspd - multiplier for dx
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and dy on enemy bullets.
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default is 0.5, making enemy
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shots much easier to dodge
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* damage - damage per hit;
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used by ships
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* sprite - sprite index.
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* x_off, y_off - renamed for
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the next two vars. may revert
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* center_off_x - the horizontal
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centerpoint of the bullet,
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for positioning when firing.
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assume a pixel's coordinates
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refer to the upper left corner
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of the pixel; the center of
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a 2-width bullet with an
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upper left corner at 0 is 1,
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not 0.5.
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* top_off_y, bottom_off_y -
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also for positioning when
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firing. positive distance from
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top or bottom edge to image.
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top_off_y will usually be 0,
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bottom_off_y will not be when
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bullets are smaller than
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the sprite box.
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* width, height - measured in
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full sprites (8x8 boxes), not
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pixels. used for drawing.
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bullets despawn when above or
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below the screen (player or
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enemy bullets, respectively).
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by default, bullets despawn
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when they hit something.
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override hitship to change this.
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ships
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____
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ships move by calculating
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momentum, then offsetting their
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position by that momentum, then
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clamping their position to the
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screen (horizontally only for
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ships that autoscroll). ships
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that autoscroll (slip==true)
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then slide down by scrollspeed.
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fractional coordinates are ok.
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after movement, ships lose
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momentum (ship.drag along each
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axis). abs(momentum) can't
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exceed ship.maxspeed.
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ships gain momentum by acting
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like a player pushing buttons.
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the player ship actually reads
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buttons for this.
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act -- returns new acceleration:
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dx, dy, shoot_spec, shoot_main.
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dx and dy are change in momentum
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in px/frame. this is controls
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only -- friction is handled in
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ship:move (`drag` value).
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ships hitting another ship take
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1 damage per frame of overlap.
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ships hitting a bullet check
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bullet.damage to find out how
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much damage they take. damage
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is applied to shields, then hp.
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damaged ships flash briefly -
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blue (12) if all damage was
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shielded, white (7) if hp was
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damaged. a ship that then has 0
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or less hp calls self:die() and
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tells the main game loop to
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remove it.
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shieldcooldown is the interval
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between restoring shield points.
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shieldpenalty is the delay
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before restoring points after
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any damage, reset to this value
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on every damaging hit (whether
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it is absorbed by the shield or
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not) -- shield behaves like
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halo and other shooters in its
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heritage, where it recovers if
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you avoid damage for a while.
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not that there is any safe cover
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in this kind of game.
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ships do not repair hp on their
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own. negative-damage bullets
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are treated as 0, but a bullet
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can choose to repair the ship
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it hits in its own hitship
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method, or otherwise edit it
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(changing weapons, refilling
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weapon ammo). powerups are
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therefore a kind of bullet.
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levels
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======
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a level is a table mapping
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effective frame number to
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functions. when a level starts,
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it sets lframe ("level frame")
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and distance to 0.
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every frame, level_frame
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increments lframe by 0x0.0001.
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then if the level is not frozen,
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it increments distance by 1.0
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and runs the function in the
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level table for exactly that
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frame number (if any). distance
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is therefore "nonfrozen frames",
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and is used to trigger level
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progress. lframe always
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increments. ships are encouraged
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to use lframe to control
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animation and movement, and may
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use distance to react to level
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progress separately from overall
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time. remember to multiply
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lframe-related stuff by 0x0001.
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a special sentinel value, eol,
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marks the end of the level.
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(the level engine doesn't know
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when it's out of events, so
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without eol, the level will
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simply have no events forever.)
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when it finds eol, level_frame
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throws away the current level
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and tells the main loop that it
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might be done. the main loop
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agrees the level is over and the
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player has won when the level
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has reached eol and there are
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no more enemy ships, enemy
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bullets, or background events
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remaining. player ships, player
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bullets, and intangibles are
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not counted.
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level freezing
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--------------
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the level is frozen when the
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global value freeze > 0.
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generally, something intending
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to block level progress (a
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miniboss, a minigame, etc.)
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increments freeze and prepares
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some means of decrementing it
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when it no longer wants to block
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level progress.
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most commonly, we want to block
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until some specific ship or
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group of ships has died. for
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these ships, override ship:die
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to decrement freeze. make sure
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to set ship.dead in any new
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ship:die method so anything else
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looking at it can recognize
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the ship as dead.
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for anything else, you probably
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want an event to figure out when
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to unfreeze.
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levels start at 1
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-----------------
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distance is initialized to 0
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but gets incremented before the
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first time the engine looks for
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events. therefore, the first
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frame of the level executes
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level[1]. since levelframe
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executes before anything else,
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level[1] sets up the first frame
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drawn in the level. the player
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does not see a blank world
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before level[1] runs.
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level[1] can therefore be used
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to reconfigure the player ship,
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set up backgrounds, start music,
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kick off some kind of fade-in
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animation, etc.
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events
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======
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the global list "events" stores
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0-argument functions which are
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called every frame. if they
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return true, they are removed
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from the list and not run again;
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if they return false, they stay
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and will be called in later
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frames. the level does not end
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while the events table is
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nonempty.
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events are most commonly used
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to set up something for later
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(for example, blip uses an event
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to remove the fx_pallete from
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the flashing ship when the blip
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expires), but can also be used
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to implement a "level within a
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level" that does something
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complicated until it's done. if
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you froze the level when
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creating the event, remember
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to thaw it (freeze -= 1) on all
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paths that return true.
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to do complex stuff in events,
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use a closure or a metatable
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that specifies __call.
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to avoid editing the events
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list while it is being iterated,
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events that create new events
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must add those events to
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new_events rather than events.
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new_events is only valid during
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the "event execution" stage, so
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events created at any other time
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must go directly on events
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without using new_events.
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intangibles
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===========
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the intangibles_fg and
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intangibles_bg lists contain
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items with :move and :draw.
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like ships and bullets, they
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move during _update60 and
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draw during _draw. they are
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not checked for collisions.
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intangibles_bg moves/draws
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before anything else moves or
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draws. intangibles_fg
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moves/draws last. this controls
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whether your intangible object
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draws in front of or behind
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other stuff. you probably want
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intangibles_bg for decorative
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elements and intangibles_fg
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for explosions, score popups,
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etc.
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there's no scrolling background
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engine but intangibles_bg could
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be used to create one, including
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using the map (otherwise unused
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in this engine) for the purpose.
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intangibles do not prevent the
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level from ending. like bullets
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and ships, if :move returns
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true, they are dropped.
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@ -1,87 +0,0 @@
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pico-8 cartridge // http://www.pico-8.com
|
||||
version 42
|
||||
__lua__
|
||||
-- vacuum gambit
|
||||
-- by kistaro windrider
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||||
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function _draw()
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cls()
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draw_hud_placeholder()
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draw_weap_opt(0,0,frame_col(item==1),1,"hull","\n +1\n max\nhealth")
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draw_weap_opt(56,0,frame_col(item==2),2,"vulc"," rate\n\n faster\n firing\n rate")
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draw_rearm(frame_col(item<0))
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end
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function _init()
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item=1
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bfm=1
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end
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|
||||
function _update()
|
||||
if (btn(3) and item > 0 or btn(2) and item < 0) item = -item
|
||||
if (btn(0)) item = 1
|
||||
if (btn(1)) item = 2
|
||||
if (btn() & 0xF ~= 0) and bfm >= 10 or bfm >= 30 then
|
||||
bfm = 1
|
||||
else
|
||||
bfm += 1
|
||||
end
|
||||
end
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||||
|
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function draw_hud_placeholder()
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||||
rectfill(112, 0, 127, 127,0x56)
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||||
rect(112,0,127,127,7)
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||||
line(127,1,127,127,5)
|
||||
line(113,127)
|
||||
end
|
||||
|
||||
function glow_box(x0, y0, x1, y1, c, cf)
|
||||
rect(x0, y0, x1, y1, c[1])
|
||||
rect(x0+1, y0+1, x1-1, y1-1, c[2])
|
||||
rect(x0+2, y0+2, x1-2, y1-2, c[1])
|
||||
if cf then
|
||||
-- todo: animate "dot crawl" background
|
||||
fillp(…)
|
||||
rectfill(x0+3, y0+3, x1-3, y1-3, cf)
|
||||
fillp()
|
||||
end
|
||||
end
|
||||
|
||||
function frame_col(hot)
|
||||
if (not hot) return {4,10}
|
||||
if (bfm<=16) return {14,7}
|
||||
return {2,8}
|
||||
end
|
||||
|
||||
function draw_weap_opt(x, y, c, s, hdr, body)
|
||||
camera(-x,-y)
|
||||
glow_box(0,0,55,100,c,1)
|
||||
spr(s,5, 5)
|
||||
print(hdr, 13, 8, 7)
|
||||
print(body, 5, 15, 6)
|
||||
camera()
|
||||
end
|
||||
|
||||
function draw_rearm(c)
|
||||
glow_box(0,101,111,127,c,1)
|
||||
spr(5,15,107,4,2)
|
||||
print("full ammo\nfull shield\n+50% health",54, 106, 6)
|
||||
end
|
||||
|
||||
__gfx__
|
||||
000000000b00000000000a0007700770000aa0000444440004444444000000000000000000000000000000000000000000000000000000000000000000000000
|
||||
00000000bba80880000008000aa00aa00a0880a0447777700477777a000000000000000000000000000000000000000000000000000000000000000000000000
|
||||
007007000aaa28780a0000000990099008000080477aaa7a0477aaaa000000000000000000000000000000000000000000000000000000000000000000000000
|
||||
0007000008a8887808000000099009900080080047a0047a047a0000000000000000000000000000000000000000000000000000000000000000000000000000
|
||||
00007000088888820000a000088008800000000047a0447a047a0000000000000000000000000000000000000000000000000000000000000000000000000000
|
||||
00700700008888200000800008800880a000000a47a4477a047a4440000000000000000000000000000000000000000000000000000000000000000000000000
|
||||
000000000008820000a0000008800880080aa080477777a00477777a000000000000000000000000000000000000000000000000000000000000000000000000
|
||||
0000000000002000008000000880088000088000477770000422aaaa222200020000020000000000000000000000000000000000000000000000000000000000
|
||||
000000000000000000000000000000000000000047a77700022ee0002eeee002e00022e000000000000000000000000000000000000000000000000000000000
|
||||
000000000000000000000000000000000000000047a4777002ea2e002e002e02ee022ee000000000000000000000000000000000000000000000000000000000
|
||||
000000000000000000000000000000000000000047a0477a22ea2e002e002e02e2e2e2e000000000000000000000000000000000000000000000000000000000
|
||||
000000000000000000000000000000000000000047a0047a2e2222e02e222e02e02e02e000000000000000000000000000000000000000000000000000000000
|
||||
000000000000000000000000000000000000000047a0047a2eeeeeea2eeee002e02e02e000000000000000000000000000000000000000000000000000000000
|
||||
00000000000000000000000000000000000000000aa000aa2e7aa2ea2e00e002e02e02e000000000000000000000000000000000000000000000000000000000
|
||||
0000000000000000000000000000000000000000000000002e0002e02e002e02e02e02e000000000000000000000000000000000000000000000000000000000
|
||||
0000000000000000000000000000000000000000000000000e0000e00e000e00e00e00e000000000000000000000000000000000000000000000000000000000
|
||||
366
vacuum_gambit.p8
366
vacuum_gambit.p8
@ -340,11 +340,11 @@ function drawhud()
|
||||
draw_gun_info("🅾️",1,116,29,primary_ship.special_gun)
|
||||
|
||||
inset(114,57,119,118)
|
||||
rectfill(119,57,124,58,13)
|
||||
rectfill(119,57,125,58,13)
|
||||
inset(120,64,125,125)
|
||||
rectfill(114,124,120,125,7)
|
||||
print("XP",119,55,1)
|
||||
print("HP",114,122,1)
|
||||
rectfill(114,124,120,125,13)
|
||||
print("XP",120,56,1)
|
||||
print("HP",113,121,1)
|
||||
fillp(0x5a5a)
|
||||
vertmeter(115,58,118,117,primary_ship.xp, primary_ship.xptarget, powcols)
|
||||
-- 59 px vertically
|
||||
@ -409,7 +409,7 @@ function inset(x0,y0,x1,y1)
|
||||
-- fillp
|
||||
rect(x0,y0,x1,y1,119)
|
||||
line(x1,y0,x0,y0,85)
|
||||
line(x0,y1-1,85)
|
||||
line(x0,y1,85)
|
||||
end
|
||||
|
||||
function dropshadow(str, x, y, col)
|
||||
@ -1415,6 +1415,362 @@ example_level_csv=[[1,spawn_frownie
|
||||
720,spawn_blocking_boss_chasey
|
||||
721,eol]]
|
||||
|
||||
-->8
|
||||
-- readme.md
|
||||
|
||||
--[[
|
||||
|
||||
main loop sequence
|
||||
==================
|
||||
1. level_frame
|
||||
2. events
|
||||
3. merge new_events into events
|
||||
4. update bg intangibles
|
||||
5. move ships (player first)
|
||||
6. move bullets (player first)
|
||||
7. calculate collisions
|
||||
1. pship on eship
|
||||
2. ebullet on pship
|
||||
3. pbullet on eship
|
||||
8. update fg intangibles
|
||||
9. check for end of level
|
||||
|
||||
draw order
|
||||
----------
|
||||
bottom to top:
|
||||
1. intangibles_bg
|
||||
2. player bullets
|
||||
3. player ships
|
||||
4. enemy ships
|
||||
5. enemy bullets
|
||||
6. intangibles_fg
|
||||
|
||||
notes
|
||||
-----
|
||||
intangibles_fg move()s after
|
||||
all collisions and other moves
|
||||
are processed. if an intangible
|
||||
is added to the list as a result
|
||||
of a collision or move, it will
|
||||
itself be move()d before it is
|
||||
drawn.
|
||||
|
||||
data-driven items
|
||||
=================
|
||||
guns and bullets both allow the
|
||||
most common behaviors to be
|
||||
expressed with data alone.
|
||||
ships only need a movement
|
||||
algorithm expressed.
|
||||
|
||||
guns
|
||||
----
|
||||
* t - metatable for bullet type.
|
||||
fired once in the bullet's
|
||||
default direction per shot.
|
||||
* enemy - if true, fired bullets
|
||||
are flagged as enemy bullets.
|
||||
* icon - sprite index of an
|
||||
8x8 sprite to display in the
|
||||
hud when the player has this
|
||||
gun. default is 20, a generic
|
||||
crosshair bullseye thing.
|
||||
* cooldown - min frames between
|
||||
shots.
|
||||
* ammo, maxammo - permitted
|
||||
number of shots. 0 is empty
|
||||
and unfireable. maxammo = 0
|
||||
will cause a divide by zero
|
||||
so don't do that. if nil,
|
||||
ammo is infinite.
|
||||
|
||||
default guns manage ammo and
|
||||
cooldown in shoot, then call
|
||||
actually_shoot to create the
|
||||
projectile. override only
|
||||
actually_shoot to change
|
||||
projectile logic while keeping
|
||||
cooldown and ammo logic.
|
||||
|
||||
bullets
|
||||
-------
|
||||
* dx, dy - movement per frame.
|
||||
player bullets use -dy
|
||||
instead.
|
||||
* enemyspd - multiplier for dx
|
||||
and dy on enemy bullets.
|
||||
default is 0.5, making enemy
|
||||
shots much easier to dodge
|
||||
* damage - damage per hit;
|
||||
used by ships
|
||||
* sprite - sprite index.
|
||||
* x_off, y_off - renamed for
|
||||
the next two vars. may revert
|
||||
* center_off_x - the horizontal
|
||||
centerpoint of the bullet,
|
||||
for positioning when firing.
|
||||
assume a pixel's coordinates
|
||||
refer to the upper left corner
|
||||
of the pixel; the center of
|
||||
a 2-width bullet with an
|
||||
upper left corner at 0 is 1,
|
||||
not 0.5.
|
||||
* top_off_y, bottom_off_y -
|
||||
also for positioning when
|
||||
firing. positive distance from
|
||||
top or bottom edge to image.
|
||||
top_off_y will usually be 0,
|
||||
bottom_off_y will not be when
|
||||
bullets are smaller than
|
||||
the sprite box.
|
||||
* width, height - measured in
|
||||
full sprites (8x8 boxes), not
|
||||
pixels. used for drawing.
|
||||
|
||||
bullets despawn when above or
|
||||
below the screen (player or
|
||||
enemy bullets, respectively).
|
||||
|
||||
by default, bullets despawn
|
||||
when they hit something.
|
||||
override hitship to change this.
|
||||
|
||||
ships
|
||||
____
|
||||
|
||||
ships move by calculating
|
||||
momentum, then offsetting their
|
||||
position by that momentum, then
|
||||
clamping their position to the
|
||||
screen (horizontally only for
|
||||
ships that autoscroll). ships
|
||||
that autoscroll (slip==true)
|
||||
then slide down by scrollspeed.
|
||||
fractional coordinates are ok.
|
||||
after movement, ships lose
|
||||
momentum (ship.drag along each
|
||||
axis). abs(momentum) can't
|
||||
exceed ship.maxspeed.
|
||||
|
||||
ships gain momentum by acting
|
||||
like a player pushing buttons.
|
||||
the player ship actually reads
|
||||
buttons for this.
|
||||
|
||||
act -- returns new acceleration:
|
||||
dx, dy, shoot_spec, shoot_main.
|
||||
dx and dy are change in momentum
|
||||
in px/frame. this is controls
|
||||
only -- friction is handled in
|
||||
ship:move (`drag` value).
|
||||
|
||||
ships hitting another ship take
|
||||
1 damage per frame of overlap.
|
||||
ships hitting a bullet check
|
||||
bullet.damage to find out how
|
||||
much damage they take. damage
|
||||
is applied to shields, then hp.
|
||||
damaged ships flash briefly -
|
||||
blue (12) if all damage was
|
||||
shielded, white (7) if hp was
|
||||
damaged. a ship that then has 0
|
||||
or less hp calls self:die() and
|
||||
tells the main game loop to
|
||||
remove it.
|
||||
|
||||
shieldcooldown is the interval
|
||||
between restoring shield points.
|
||||
shieldpenalty is the delay
|
||||
before restoring points after
|
||||
any damage, reset to this value
|
||||
on every damaging hit (whether
|
||||
it is absorbed by the shield or
|
||||
not) -- shield behaves like
|
||||
halo and other shooters in its
|
||||
heritage, where it recovers if
|
||||
you avoid damage for a while.
|
||||
not that there is any safe cover
|
||||
in this kind of game.
|
||||
|
||||
ships do not repair hp on their
|
||||
own. negative-damage bullets
|
||||
are treated as 0, but a bullet
|
||||
can choose to repair the ship
|
||||
it hits in its own hitship
|
||||
method, or otherwise edit it
|
||||
(changing weapons, refilling
|
||||
weapon ammo). powerups are
|
||||
therefore a kind of bullet.
|
||||
|
||||
levels
|
||||
======
|
||||
|
||||
a level is a table mapping
|
||||
effective frame number to
|
||||
functions. when a level starts,
|
||||
it sets lframe ("level frame")
|
||||
and distance to 0.
|
||||
|
||||
every frame, level_frame
|
||||
increments lframe by 0x0.0001.
|
||||
then if the level is not frozen,
|
||||
it increments distance by 1.0
|
||||
and runs the function in the
|
||||
level table for exactly that
|
||||
frame number (if any). distance
|
||||
is therefore "nonfrozen frames",
|
||||
and is used to trigger level
|
||||
progress. lframe always
|
||||
increments. ships are encouraged
|
||||
to use lframe to control
|
||||
animation and movement, and may
|
||||
use distance to react to level
|
||||
progress separately from overall
|
||||
time. remember to multiply
|
||||
lframe-related stuff by 0x0001.
|
||||
|
||||
a special sentinel value, eol,
|
||||
marks the end of the level.
|
||||
(the level engine doesn't know
|
||||
when it's out of events, so
|
||||
without eol, the level will
|
||||
simply have no events forever.)
|
||||
when it finds eol, level_frame
|
||||
throws away the current level
|
||||
and tells the main loop that it
|
||||
might be done. the main loop
|
||||
agrees the level is over and the
|
||||
player has won when the level
|
||||
has reached eol and there are
|
||||
no more enemy ships, enemy
|
||||
bullets, or background events
|
||||
remaining. player ships, player
|
||||
bullets, and intangibles are
|
||||
not counted.
|
||||
|
||||
level freezing
|
||||
--------------
|
||||
the level is frozen when the
|
||||
global value freeze > 0.
|
||||
generally, something intending
|
||||
to block level progress (a
|
||||
miniboss, a minigame, etc.)
|
||||
increments freeze and prepares
|
||||
some means of decrementing it
|
||||
when it no longer wants to block
|
||||
level progress.
|
||||
|
||||
most commonly, we want to block
|
||||
until some specific ship or
|
||||
group of ships has died. for
|
||||
these ships, override ship:die
|
||||
to decrement freeze. make sure
|
||||
to set ship.dead in any new
|
||||
ship:die method so anything else
|
||||
looking at it can recognize
|
||||
the ship as dead.
|
||||
|
||||
for anything else, you probably
|
||||
want an event to figure out when
|
||||
to unfreeze.
|
||||
|
||||
levels start at 1
|
||||
-----------------
|
||||
|
||||
distance is initialized to 0
|
||||
but gets incremented before the
|
||||
first time the engine looks for
|
||||
events. therefore, the first
|
||||
frame of the level executes
|
||||
level[1]. since levelframe
|
||||
executes before anything else,
|
||||
level[1] sets up the first frame
|
||||
drawn in the level. the player
|
||||
does not see a blank world
|
||||
before level[1] runs.
|
||||
level[1] can therefore be used
|
||||
to reconfigure the player ship,
|
||||
set up backgrounds, start music,
|
||||
kick off some kind of fade-in
|
||||
animation, etc.
|
||||
|
||||
|
||||
events
|
||||
======
|
||||
the global list "events" stores
|
||||
0-argument functions which are
|
||||
called every frame. if they
|
||||
return true, they are removed
|
||||
from the list and not run again;
|
||||
if they return false, they stay
|
||||
and will be called in later
|
||||
frames. the level does not end
|
||||
while the events table is
|
||||
nonempty.
|
||||
|
||||
events are most commonly used
|
||||
to set up something for later
|
||||
(for example, blip uses an event
|
||||
to remove the fx_pallete from
|
||||
the flashing ship when the blip
|
||||
expires), but can also be used
|
||||
to implement a "level within a
|
||||
level" that does something
|
||||
complicated until it's done. if
|
||||
you froze the level when
|
||||
creating the event, remember
|
||||
to thaw it (freeze -= 1) on all
|
||||
paths that return true.
|
||||
|
||||
to do complex stuff in events,
|
||||
use a closure or a metatable
|
||||
that specifies __call.
|
||||
|
||||
to avoid editing the events
|
||||
list while it is being iterated,
|
||||
events that create new events
|
||||
must add those events to
|
||||
new_events rather than events.
|
||||
new_events is only valid during
|
||||
the "event execution" stage, so
|
||||
events created at any other time
|
||||
must go directly on events
|
||||
without using new_events.
|
||||
|
||||
intangibles
|
||||
===========
|
||||
|
||||
the intangibles_fg and
|
||||
intangibles_bg lists contain
|
||||
items with :move and :draw.
|
||||
like ships and bullets, they
|
||||
move during _update60 and
|
||||
draw during _draw. they are
|
||||
not checked for collisions.
|
||||
|
||||
intangibles_bg moves/draws
|
||||
before anything else moves or
|
||||
draws. intangibles_fg
|
||||
moves/draws last. this controls
|
||||
whether your intangible object
|
||||
draws in front of or behind
|
||||
other stuff. you probably want
|
||||
intangibles_bg for decorative
|
||||
elements and intangibles_fg
|
||||
for explosions, score popups,
|
||||
etc.
|
||||
|
||||
there's no scrolling background
|
||||
engine but intangibles_bg could
|
||||
be used to create one, including
|
||||
using the map (otherwise unused
|
||||
in this engine) for the purpose.
|
||||
|
||||
intangibles do not prevent the
|
||||
level from ending. like bullets
|
||||
and ships, if :move returns
|
||||
true, they are dropped.
|
||||
]]
|
||||
-->8
|
||||
-- standard events
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user