717 lines
23 KiB
Standard ML
717 lines
23 KiB
Standard ML
structure Player =
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struct
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open PlayerPatch
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open EntityType
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open PlayerType
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(* helper functions checking input *)
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fun getXAxis (lh, rh) =
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case (lh, rh) of
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(false, false) => STAY_STILL
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| (false, true) => MOVE_RIGHT
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| (true, false) => MOVE_LEFT
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| (true, true) => STAY_STILL
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fun getFacing (facing, xAxis) =
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case xAxis of
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STAY_STILL => facing
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| MOVE_LEFT => FACING_LEFT
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| MOVE_RIGHT => FACING_RIGHT
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(* function returns default yAxis when neither up/down are pressed
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* or both are pressed.
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*
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* In the case where the user was previously jumping,
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* we enter the floating stage, because it's normal for games
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* to have a very brief floating/gliding period before applying gravity.
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*
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* In the case where the user was previously floating, we want the player to
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* keep floating at this point (another function will apply gravity if we
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* floated enough).
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*
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* In every other case, we return the FALLING variant,
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* which has the same effect as returning the ON_GROUND variant,
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* except that it means gravity is applied if we walk off a platform.
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* *)
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fun defaultYAxis prevAxis =
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case prevAxis of
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JUMPING _ => FLOATING 0
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| FLOATING _ => prevAxis
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| DROP_BELOW_PLATFORM => prevAxis
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| _ => FALLING
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(* We want to prevent a double jump
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* or jumping while the player is falling
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* so we only switch to the JUMPING case if the player
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* is on the ground. *)
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fun onJumpPressed (prevAxis, jumpPressed) =
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case prevAxis of
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ON_GROUND =>
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if jumpPressed then (* apply gravity *) FALLING else JUMPING 0
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| _ => prevAxis
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fun getJumpPatches (player, jumpHeld, downHeld, acc) =
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let
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val {yAxis, jumpPressed, ...} = player
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in
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case (jumpHeld, downHeld) of
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(false, false) =>
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let
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val yAxis = defaultYAxis yAxis
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val jumpPressed = false
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in
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W_JUMP_PRESSED jumpPressed :: W_Y_AXIS yAxis :: acc
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end
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| (true, true) =>
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let val yAxis = defaultYAxis yAxis
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in W_Y_AXIS yAxis :: acc
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end
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| (true, false) =>
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let
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val yAxis = onJumpPressed (yAxis, jumpPressed)
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val jumpPressed = true
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in
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W_Y_AXIS yAxis :: W_JUMP_PRESSED jumpPressed :: acc
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end
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| (false, true) =>
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let
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val jumpPressed = false
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val yAxis = DROP_BELOW_PLATFORM
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in
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W_Y_AXIS yAxis :: W_JUMP_PRESSED jumpPressed :: acc
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end
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end
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(* called only when player has no projectiles or was not previously attacking *)
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fun helpGetMainAttackPatches (attackHeld, mainAttackPressed, charge, acc) =
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let
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val attack =
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if attackHeld andalso not mainAttackPressed then
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MAIN_ATTACKING {length = 3, growing = true}
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else
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MAIN_NOT_ATTACKING
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in
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W_MAIN_ATTACK_PRESSED (attackHeld andalso mainAttackPressed)
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:: W_MAIN_ATTACK attack :: acc
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end
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fun degreesToRadians degrees = Real32.fromInt degrees * Constants.projectilePi
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fun defeatedEnemiesToProjectiles
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(pos, defeteadEnemies, player as {x, y, facing, ...}, acc) =
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if pos = Vector.length defeteadEnemies then
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Vector.fromList acc
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else
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let
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val halfProjectileSize = Constants.projectileSize / 2.0
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val diffX = Constants.halfPlayerWidthReal - halfProjectileSize
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val diffY = Constants.halfPlayerHeightReal - halfProjectileSize
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val x = Real32.fromInt x + diffX
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val y = Real32.fromInt y + diffY
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val {angle} = Vector.sub (defeteadEnemies, pos)
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val angle = degreesToRadians angle
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val x = ((Real32.Math.cos angle) * Constants.projectileDistance) + x
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val y = ((Real32.Math.sin angle) * Constants.projectileDistance) + y
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val x = Real32.toInt IEEEReal.TO_NEAREST x
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val y = Real32.toInt IEEEReal.TO_NEAREST y
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val acc = {x = x, y = y, facing = facing} :: acc
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in
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defeatedEnemiesToProjectiles (pos + 1, defeteadEnemies, player, acc)
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end
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fun getThrowPatches (defeteadEnemies, projectiles, player, acc) =
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let
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val newProjectiles =
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defeatedEnemiesToProjectiles (0, defeteadEnemies, player, [])
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(* concatenate new projectiles with previous projectiles *)
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val allProjectiles = Vector.concat [newProjectiles, projectiles]
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(* remove defeated enemies from player record *)
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val enemies = Vector.fromList []
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in
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W_MAIN_ATTACK MAIN_THROWING :: W_PROJECTILES allProjectiles
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:: W_ENEMIES enemies :: acc
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end
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fun getMainAttackPatches
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( prevAttack
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, defeteadEnemies
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, projectiles
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, attackHeld
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, charge
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, player
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, acc
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, mainAttackPressed
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) =
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case prevAttack of
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MAIN_NOT_ATTACKING =>
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if
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attackHeld andalso not mainAttackPressed
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andalso Vector.length defeteadEnemies > 0
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then
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(* shoot projectiles if player was not attacking previously,
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* and there is more than one enemy *)
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getThrowPatches (defeteadEnemies, projectiles, player, acc)
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else
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helpGetMainAttackPatches (attackHeld, mainAttackPressed, charge, acc)
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| MAIN_ATTACKING {length, growing} =>
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let
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val mainAttack =
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if growing then
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if length < Constants.attackLengthLimit then
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let val newLength = length + Constants.moveProjectileBy
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in MAIN_ATTACKING {length = newLength, growing = true}
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end
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else
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let
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val newLength = length - Constants.moveProjectileBy
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in
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if newLength <= 0 then MAIN_NOT_ATTACKING
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else MAIN_ATTACKING {length = newLength, growing = false}
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end
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else
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let
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val newLength = length - Constants.moveProjectileBy
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in
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if newLength <= 0 then MAIN_NOT_ATTACKING
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else MAIN_ATTACKING {length = newLength, growing = false}
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end
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in
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W_MAIN_ATTACK_PRESSED true :: W_MAIN_ATTACK mainAttack :: acc
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end
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| MAIN_THROWING =>
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if attackHeld then
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acc
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else
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helpGetMainAttackPatches (attackHeld, mainAttackPressed, charge, acc)
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fun getInputPatches (player: player, input: FrameInputType.t) =
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let
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val
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{ x
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, y
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, yAxis
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, jumpPressed
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, facing
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, mainAttack
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, mainAttackPressed
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, charge
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, enemies
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, projectiles
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, ...
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} = player
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val {leftHeld, rightHeld, upHeld, downHeld, attackHeld, jumpHeld, ...} =
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input
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val xAxis = getXAxis (leftHeld, rightHeld)
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val facing = getFacing (facing, xAxis)
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val charge = (* todo: rework charge *) charge
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val acc = [W_X_AXIS xAxis, W_FACING facing, W_CHARGE charge]
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val acc = getMainAttackPatches
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( mainAttack
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, enemies
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, projectiles
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, attackHeld
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, charge
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, player
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, acc
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, mainAttackPressed
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)
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val acc = getJumpPatches (player, jumpHeld, downHeld, acc)
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in
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acc
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end
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fun getRecoilPatches (player: player, patches) =
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case #recoil player of
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NO_RECOIL => patches
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| RECOIL_LEFT recoiled =>
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(* if player is recoiling, don't accept or adjust any input.
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* However, if player has reached the recoil limit, exit the recoil
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* state and accept input.
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* *)
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if recoiled = Constants.recoilLimit then
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W_RECOIL NO_RECOIL :: patches
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else
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let
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val {x, y, health, attacked, facing, xAxis, ...} = player
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(* difference between RECOIL_LEFT and RECOIL_RIGHT
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* is the direction player moves back in *)
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val x = x - 5
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val xAxis = STAY_STILL
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val yAxis = FALLING
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val jumpPressed = false
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val recoiled = recoiled + 1
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val recoil = RECOIL_LEFT recoiled
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val facing = getFacing (facing, xAxis)
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in
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W_X x :: W_X_AXIS xAxis :: W_Y_AXIS yAxis
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:: W_JUMP_PRESSED jumpPressed :: W_RECOIL recoil :: W_FACING facing
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:: patches
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end
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| RECOIL_RIGHT recoiled =>
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if recoiled = Constants.recoilLimit then
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W_RECOIL NO_RECOIL :: patches
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else
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let
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val {x, y, health, attacked, facing, xAxis, ...} = player
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val x = x + 5
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val xAxis = STAY_STILL
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val yAxis = FALLING
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val jumpPressed = false
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val recoiled = recoiled + 1
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val recoil = RECOIL_RIGHT recoiled
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val facing = getFacing (facing, xAxis)
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in
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W_X x :: W_X_AXIS xAxis :: W_Y_AXIS yAxis
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:: W_JUMP_PRESSED jumpPressed :: W_RECOIL recoil :: W_FACING facing
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:: patches
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end
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fun helpMoveProjectiles (pos, projectiles, acc) =
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if pos < 0 then
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Vector.fromList acc
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else
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let
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val {x, y, facing} = Vector.sub (projectiles, pos)
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in
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if x <= 0 orelse x >= Constants.worldWidth then
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(* filter out since projectile is not visible *)
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helpMoveProjectiles (pos - 1, projectiles, acc)
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else
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let
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val x =
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case facing of
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FACING_LEFT => x - Constants.moveProjectileBy
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| FACING_RIGHT => x + Constants.moveProjectileBy
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val newTile = {x = x, y = y, facing = facing}
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val acc = newTile :: acc
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in
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helpMoveProjectiles (pos - 1, projectiles, acc)
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end
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end
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fun getProjectilePatches ({projectiles, ...}: player) =
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let
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val newProjectiles = helpMoveProjectiles
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(Vector.length projectiles - 1, projectiles, [])
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in
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[W_PROJECTILES newProjectiles]
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end
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structure FoldEnemies =
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MakeQuadTreeFold
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(struct
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type env = EnemyMap.t * player
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type state = PlayerPatch.player_patch list
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fun getEnemyRecoilPatches (player, playerOnRight, acc) =
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if playerOnRight then
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let
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val newRecoil = RECOIL_RIGHT 0
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val newAttacked = ATTACKED 0
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in
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W_RECOIL newRecoil :: W_ATTACKED newAttacked
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:: W_FACING FACING_LEFT :: W_Y_AXIS FALLING
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:: W_X_AXIS STAY_STILL :: acc
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end
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else
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let
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val newRecoil = RECOIL_LEFT 0
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val newAttacked = ATTACKED 0
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in
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W_RECOIL newRecoil :: W_ATTACKED newAttacked
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:: W_FACING FACING_RIGHT :: W_Y_AXIS FALLING
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:: W_X_AXIS STAY_STILL :: acc
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end
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fun fold (enemyID, (enemies, player: player), patches) =
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let
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val playerOnRight =
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(* check if collision is closer to left side of enemy or right
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* and then chose appropriate direction to recoil in *)
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let
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val {x, ...} = player
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val pFinishX = x + Constants.playerWidth
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val pHalfW = Constants.playerWidth div 2
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val pCentreX = x + pHalfW
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in
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case EnemyMap.get (enemyID, enemies) of
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SOME {x = ex, y = ey, ...} =>
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let
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val eFinishX = ex + Constants.enemySize
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val eHalfW = Constants.enemySize div 2
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val eCentreX = ex + eHalfW
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in
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eCentreX < pCentreX
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end
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| NONE => false
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end
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val patches =
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getEnemyRecoilPatches (player, playerOnRight, patches)
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in
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W_ATTACKED (ATTACKED 0) :: patches
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end
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end)
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structure AttackEnemies =
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MakeQuadTreeFold
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(struct
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type env = unit
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type state = defeated_enemies list
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fun fold (_, (), defeatedList) = {angle = 1} :: defeatedList
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end)
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fun runPhysicsAndInput (game: LevelType.level_type, input) =
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let
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val player = #player game
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val patches = getProjectilePatches player
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val patches = getRecoilPatches (player, patches)
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val player = PlayerPatch.withPatches (player, patches)
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val patches =
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(* we only accept and handle input if player is not recoiling.
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* It's important to apply the recoil patches after handling input
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* because we want to act on the latest recoil state straight away. *)
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case #recoil player of
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NO_RECOIL => getInputPatches (player, input)
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| _ => []
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val patches =
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(* control timer for how long player should be immune to damage
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* after being attacked *)
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case #attacked player of
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ATTACKED amt =>
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if amt >= Constants.attackedLimit then
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W_ATTACKED NOT_ATTACKED :: patches
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else
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W_ATTACKED (ATTACKED (amt + 1)) :: patches
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| _ => patches
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(* animate projectiles *)
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val player =
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let
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val e = #enemies player
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val e =
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Vector.map
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(fn {angle} => {angle = if angle < 360 then angle + 5 else 0}) e
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val patches = W_ENEMIES e :: patches
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in
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PlayerPatch.withPatches (player, patches)
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end
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val patches = PlayerPhysics.getPhysicsPatches player
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val player = PlayerPatch.withPatches (player, patches)
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val {walls, wallTree, platforms, platformTree, ...} = game
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val patches = PlayerPhysics.getEnvironmentPatches
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(player, walls, wallTree, platforms, platformTree)
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in
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PlayerPatch.withPatches (player, patches)
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end
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(* player reaction to collisions with enemies.
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* We only detect collisions if player is not in invincibility period
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* after being previously attacked. *)
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fun checkEnemyCollisions (player: PlayerType.player, enemies, enemyTree) =
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case #attacked player of
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ATTACKED _ => player
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| _ =>
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let
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val {x, y, ...} = player
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val ew = Constants.playerWidth
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val eh = Constants.playerHeight
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val env = (enemies, player)
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val state = []
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val patches = FoldEnemies.foldRegion
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(x, y, ew, eh, env, state, enemyTree)
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in
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PlayerPatch.withPatches (player, patches)
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end
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(* todo: check which enemies are being attacked by player,
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* updating player's 'defeatedEnemies' field (if enemy's health would reach 0)
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* and updating enemy (if enemy's health wouldn't reach 0, decrement health)
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val patches =
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(* if player is attacking, check if enemies collide with attack *)
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case #mainAttack player of
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MAIN_ATTACKING {length, ...} =>
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let
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val height = Constants.playerSize
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val {x, y, facing, enemies, ...} = player
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val x =
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(case facing of
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FACING_RIGHT => x + Constants.playerSize
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| FACING_LEFT => x - length)
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val state = []
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(* detect collisions from enemies who are hit by attack *)
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val newDefeated = AttackEnemies.foldRegion
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(x, y, length, height, (), state, enemyTree)
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(* detect collisions from falling enemies too *)
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val fallingTree =
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FallingEnemies.generateTree (#fallingEnemies game)
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val newDefeated = AttackEnemies.foldRegion
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(x, y, length, height, (), newDefeated, fallingTree)
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val allDefeated =
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Vector.concat [Vector.fromList newDefeated, enemies]
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in
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W_ENEMIES allDefeated :: patches
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end
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| _ => patches
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in
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PlayerPatch.withPatches (player, patches)
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end
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*)
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(* todo: add attacked enemies to player's 'enemies' field *)
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fun concatAttackedEnemies (player: player, enemyCollisions) =
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let
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val newDefeated = Vector.map (fn id => {angle = 360}) enemyCollisions
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val oldDefeated = #enemies player
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val allDefeated = Vector.concat [oldDefeated, newDefeated]
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in
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PlayerPatch.withPatch (player, W_ENEMIES allDefeated)
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end
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(*** DRAWING FUNCTIONS ***)
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(* block is placeholder asset *)
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fun helpGetDrawVec
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(x, y, realWidth, realHeight, width, height, attacked, mainAttack) =
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let
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val (r, g, b) =
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case attacked of
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NOT_ATTACKED => (1.0, 1.0, 1.0)
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| ATTACKED amt =>
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if amt mod 5 = 0 then (1.0, 1.0, 1.0) else (1.0, 0.75, 0.75)
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in
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PlayerSprite.lerp (x, y, realWidth, realHeight, width, height, r, g, b)
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end
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fun getDrawVec (player: player, width, height) =
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let
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val {x, y, attacked, mainAttack, ...} = player
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val wratio = width / Constants.worldWidthReal
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val hratio = height / Constants.worldHeightReal
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in
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if wratio < hratio then
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let
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val scale = Constants.worldHeightReal * wratio
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val yOffset =
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if height > scale then (height - scale) / 2.0
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else if height < scale then (scale - height) / 2.0
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else 0.0
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val x = Real32.fromInt x * wratio
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val y = Real32.fromInt y * wratio + yOffset
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val realWidth = Constants.playerWidthReal * wratio
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val realHeight = Constants.playerHeightReal * wratio
|
|
in
|
|
helpGetDrawVec
|
|
(x, y, realWidth, realHeight, width, height, attacked, mainAttack)
|
|
end
|
|
else
|
|
let
|
|
val scale = Constants.worldWidthReal * hratio
|
|
val xOffset =
|
|
if width > scale then (width - scale) / 2.0
|
|
else if width < scale then (scale - width) / 2.0
|
|
else 0.0
|
|
|
|
val x = Real32.fromInt x * hratio + xOffset
|
|
val y = Real32.fromInt y * hratio
|
|
|
|
val realWidth = Constants.playerWidthReal * hratio
|
|
val realHeight = Constants.playerHeightReal * hratio
|
|
in
|
|
helpGetDrawVec
|
|
(x, y, realWidth, realHeight, width, height, attacked, mainAttack)
|
|
end
|
|
end
|
|
|
|
fun getFieldVec (player: player, width, height) =
|
|
case #mainAttack player of
|
|
MAIN_ATTACKING {length, ...} =>
|
|
let
|
|
val {x, y, facing, ...} = player
|
|
val wratio = width / Constants.worldWidthReal
|
|
val hratio = height / Constants.worldHeightReal
|
|
val x =
|
|
case #facing player of
|
|
FACING_RIGHT => x + Constants.playerWidth
|
|
| FACING_LEFT => x - length
|
|
in
|
|
if wratio < hratio then
|
|
let
|
|
val scale = Constants.worldHeightReal * wratio
|
|
val yOffset =
|
|
if height > scale then (height - scale) / 2.0
|
|
else if height < scale then (scale - height) / 2.0
|
|
else 0.0
|
|
|
|
val x = Real32.fromInt x * wratio
|
|
val y = Real32.fromInt y * wratio + yOffset
|
|
|
|
val realLength = Real32.fromInt length * wratio
|
|
val realHeight = Constants.playerHeightReal * wratio
|
|
|
|
val {charge, ...} = player
|
|
val alpha = Real32.fromInt charge / 60.0
|
|
in
|
|
case facing of
|
|
FACING_RIGHT =>
|
|
ChainEdgeRight.lerp
|
|
(x, y, realLength, realHeight, width, height, 0.5, 0.5, 0.5)
|
|
| FACING_LEFT =>
|
|
ChainEdgeLeft.lerp
|
|
(x, y, realLength, realHeight, width, height, 0.5, 0.5, 0.5)
|
|
end
|
|
else
|
|
let
|
|
val scale = Constants.worldWidthReal * hratio
|
|
val xOffset =
|
|
if width > scale then (width - scale) / 2.0
|
|
else if width < scale then (scale - width) / 2.0
|
|
else 0.0
|
|
|
|
val x = Real32.fromInt x * hratio + xOffset
|
|
val y = Real32.fromInt y * hratio
|
|
|
|
val realLength = Real32.fromInt length * hratio
|
|
val realHeight = Constants.playerHeightReal * hratio
|
|
|
|
val {charge, ...} = player
|
|
val alpha = Real32.fromInt charge / 60.0
|
|
in
|
|
case facing of
|
|
FACING_RIGHT =>
|
|
ChainEdgeRight.lerp
|
|
(x, y, realLength, realHeight, width, height, 0.5, 0.5, 0.5)
|
|
| FACING_LEFT =>
|
|
ChainEdgeLeft.lerp
|
|
(x, y, realLength, realHeight, width, height, 0.5, 0.5, 0.5)
|
|
end
|
|
end
|
|
| _ => Vector.fromList []
|
|
|
|
fun helpGetPelletVec
|
|
( playerX
|
|
, playerY
|
|
, pos
|
|
, enemies
|
|
, width
|
|
, height
|
|
, ratio
|
|
, xOffset
|
|
, yOffset
|
|
, acc
|
|
) =
|
|
if pos = Vector.length enemies then
|
|
Vector.concat acc
|
|
else
|
|
let
|
|
val {angle} = Vector.sub (enemies, pos)
|
|
(* convert degrees to radians *)
|
|
val angle = degreesToRadians angle
|
|
|
|
(* calculate pellet's x and y *)
|
|
val pelletX =
|
|
((Real32.Math.cos angle) * Constants.projectileDistance) + playerX
|
|
val pelletX = pelletX * ratio + xOffset
|
|
|
|
val pelletY =
|
|
((Real32.Math.sin angle) * Constants.projectileDistance) + playerY
|
|
val pelletY = pelletY * ratio + yOffset
|
|
|
|
val defeatedSize = Constants.projectileSize * ratio
|
|
|
|
val vec = Field.lerp
|
|
( pelletX
|
|
, pelletY
|
|
, defeatedSize
|
|
, defeatedSize
|
|
, width
|
|
, height
|
|
, 0.3
|
|
, 0.9
|
|
, 0.3
|
|
, 1.0
|
|
)
|
|
val acc = vec :: acc
|
|
in
|
|
helpGetPelletVec
|
|
( playerX
|
|
, playerY
|
|
, pos + 1
|
|
, enemies
|
|
, width
|
|
, height
|
|
, ratio
|
|
, xOffset
|
|
, yOffset
|
|
, acc
|
|
)
|
|
end
|
|
|
|
fun getPelletVec (player: player, width, height) =
|
|
if Vector.length (#enemies player) = 0 then
|
|
Vector.fromList []
|
|
else
|
|
let
|
|
val {x, y, enemies, ...} = player
|
|
|
|
(* get centre (x, y) coordinates of player *)
|
|
val halfProjectileSize = Constants.projectileSize / 2.0
|
|
val diffX = Constants.halfPlayerWidthReal - halfProjectileSize
|
|
val diffY = Constants.halfPlayerHeightReal - halfProjectileSize
|
|
val x = Real32.fromInt x + diffX
|
|
val y = Real32.fromInt y + diffY
|
|
|
|
val wratio = width / Constants.worldWidthReal
|
|
val hratio = height / Constants.worldHeightReal
|
|
in
|
|
if wratio < hratio then
|
|
let
|
|
val scale = Constants.worldHeightReal * wratio
|
|
val yOffset =
|
|
if height > scale then (height - scale) / 2.0
|
|
else if height < scale then (scale - height) / 2.0
|
|
else 0.0
|
|
in
|
|
helpGetPelletVec
|
|
(x, y, 0, enemies, width, height, wratio, 0.0, yOffset, [])
|
|
end
|
|
else
|
|
let
|
|
val scale = Constants.worldWidthReal * hratio
|
|
val xOffset =
|
|
if width > scale then (width - scale) / 2.0
|
|
else if width < scale then (scale - width) / 2.0
|
|
else 0.0
|
|
in
|
|
helpGetPelletVec
|
|
(x, y, 0, enemies, width, height, hratio, xOffset, 0.0, [])
|
|
end
|
|
end
|
|
end
|