destroyulator/game/scripts/Splat.gd

extends Node
class_name Splat

## Produce doesn't break. It bursts.
##
## Everything else in this game shatters into shards, which is the wrong verb entirely
## for a tomato. So `produce` gets its own death: a wet burst of pulp in the fruit's own
## colour, a puddle left on the floor that STAYS, a squelch, and a litre counter — because
## "how much juice did you make" is a far better score for a greengrocer than "how many
## objects did you destroy".
##
## Two knock-ons that make the level play itself:
##   * Anything heavy enough landing on produce squashes it, so a collapsing pyramid
##     crushes its own bottom layer without any special code. Knock one melon off the top
##     and the pile does the rest.
##   * Puddles are SLIPPERY. Make enough juice and the floor stops cooperating, which is
##     a self-inflicted hazard — the more fun you have, the worse the footing gets.
##
## Godot 4.7 GDScript 2.0.

## Litres per item, roughly by size. A watermelon is worth a lot of tomatoes.
const YIELD := {
	"apple": 0.18, "orange": 0.22, "tomato": 0.12, "melon": 2.40,
	"cabbage": 0.35, "banana": 0.14, "generic": 0.20,
}

## Juice colour per item. This is the whole visual identity of the level's mess.
const JUICE := {
	"apple": Color(0.86, 0.78, 0.34),
	"orange": Color(0.94, 0.52, 0.08),
	"tomato": Color(0.68, 0.10, 0.07),
	"melon": Color(0.88, 0.24, 0.30),
	"cabbage": Color(0.72, 0.82, 0.48),
	"banana": Color(0.92, 0.85, 0.52),
	"generic": Color(0.85, 0.55, 0.25),
}

## A body must land at least this hard to squash what it lands on.
const CRUSH_SPEED := 2.2
## Puddles beyond this are recycled oldest-first, so a long session stays bounded.
const MAX_PUDDLES := 90
## How close to a puddle counts as standing in it.
const PUDDLE_R := 0.55

var litres := 0.0
var squashed := 0

var _host: Node3D
var _player: Node3D
var _puddles: Array = []           # [{node, pos, r}]
var _snd: Array[AudioStreamWAV] = []
var _players: Array[AudioStreamPlayer3D] = []
var _next_player := 0

func setup(host: Node3D, player: Node3D) -> void:
	_host = host
	_player = player
	for i in 3:
		_snd.append(_squelch(0.9 + i * 0.15))
	# a small pool, because a collapsing pyramid squashes a dozen things in one frame
	for i in 8:
		var p := AudioStreamPlayer3D.new()
		p.unit_size = 5.0
		p.max_db = 2.0
		host.add_child(p)
		_players.append(p)

func reset() -> void:
	litres = 0.0
	squashed = 0
	for e in _puddles:
		var n = e["node"]
		if is_instance_valid(n):
			n.queue_free()
	_puddles.clear()

## Which produce is this? Derived from the node name, which Main sets from the GLB
## filename (`produce-apple` -> `apple`).
static func kind_of(n: Node) -> String:
	var s := String(n.name).to_lower()
	for k in YIELD.keys():
		if s.contains(k):
			return k
	return "generic"

# ---------------------------------------------------------------- the burst
## Called instead of the usual shard spawn when a `produce` Smashable dies.
func burst(at: Vector3, item: String, host: Node3D) -> void:
	var col: Color = JUICE.get(item, JUICE["generic"])
	var vol: float = YIELD.get(item, YIELD["generic"])
	litres += vol
	squashed += 1
	_pulp(at, col, host, vol)
	_puddle(at, col, vol)
	_squelch_at(at)

func _pulp(at: Vector3, col: Color, host: Node3D, vol: float) -> void:
	var p := GPUParticles3D.new()
	p.one_shot = true
	p.explosiveness = 1.0
	p.amount = clampi(int(28 + vol * 40.0), 24, 140)
	p.lifetime = 1.5
	p.local_coords = false
	var pm := ParticleProcessMaterial.new()
	pm.emission_shape = ParticleProcessMaterial.EMISSION_SHAPE_SPHERE
	pm.emission_sphere_radius = 0.05
	pm.direction = Vector3(0, 1, 0)
	pm.spread = 80.0
	pm.initial_velocity_min = 1.4
	pm.initial_velocity_max = 4.6 + vol
	pm.gravity = Vector3(0, -12.0, 0)
	pm.scale_min = 0.5
	pm.scale_max = 1.6
	pm.angular_velocity_min = -500.0
	pm.angular_velocity_max = 500.0
	p.process_material = pm
	var mesh := BoxMesh.new()
	mesh.size = Vector3(0.028, 0.028, 0.028)
	var mat := StandardMaterial3D.new()
	mat.albedo_color = col
	mat.roughness = 0.35
	mesh.material = mat
	p.draw_pass_1 = mesh
	host.add_child(p)
	p.global_position = at
	p.emitting = true
	p.finished.connect(p.queue_free)

## A flat quad on the floor. Not a decal projector — this is one unshaded quad slightly
## above the carpet, which is cheap, and at grazing angles it reads exactly the same.
func _puddle(at: Vector3, col: Color, vol: float) -> void:
	var r := clampf(0.22 + vol * 0.30, 0.22, 0.95)
	var mi := MeshInstance3D.new()
	var q := QuadMesh.new()
	q.size = Vector2(r * 2.0, r * 2.0)
	mi.mesh = q
	var m := StandardMaterial3D.new()
	m.albedo_color = Color(col.r, col.g, col.b, 0.72)
	m.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
	m.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
	m.cull_mode = BaseMaterial3D.CULL_DISABLED
	m.render_priority = -1
	mi.material_override = m
	mi.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
	_host.add_child(mi)
	mi.global_position = Vector3(at.x, 0.012, at.z)
	mi.rotation = Vector3(-PI * 0.5, randf_range(0.0, TAU), 0.0)
	_puddles.append({"node": mi, "pos": mi.global_position, "r": r})
	while _puddles.size() > MAX_PUDDLES:
		var old = _puddles.pop_front()
		if is_instance_valid(old["node"]):
			old["node"].queue_free()

func _squelch_at(at: Vector3) -> void:
	if _players.is_empty():
		return
	var p := _players[_next_player]
	_next_player = (_next_player + 1) % _players.size()
	p.stream = _snd[randi() % _snd.size()]
	p.pitch_scale = randf_range(0.86, 1.18)
	p.global_position = at
	p.play()

# ---------------------------------------------------------------- slipping
## How slippery the ground is under the player, 0..1. Player reads this to cut its
## acceleration — the more juice you've made, the less the floor cooperates.
func slip_under_player() -> float:
	if _player == null:
		return 0.0
	var here := _player.global_position
	var worst := 0.0
	for e in _puddles:
		var p: Vector3 = e["pos"]
		var d := Vector2(here.x - p.x, here.z - p.z).length()
		var reach: float = float(e["r"]) + PUDDLE_R * 0.5
		if d < reach:
			worst = maxf(worst, 1.0 - d / reach)
	return worst

func hud_line() -> String:
	if squashed <= 0:
		return ""
	var slip := slip_under_player()
	return "%.1f litres   ·   %d squashed%s" % [
		litres, squashed, "   ·   SLIPPERY" if slip > 0.35 else ""]

# ---------------------------------------------------------------- audio
## Wet, short, and low. Noise through a falling low-pass, roughly.
func _squelch(pitch: float) -> AudioStreamWAV:
	var rate := 22050
	var dur := 0.30
	var n := int(rate * dur)
	var out := PackedFloat32Array()
	out.resize(n)
	var lp := 0.0
	for i in n:
		var t := float(i) / float(rate)
		var env := exp(-t * 14.0) * (1.0 - exp(-t * 200.0))
		var raw := (randf() * 2.0 - 1.0)
		# sweep the filter closed so it goes from a splat to a glop
		var k := clampf(0.55 - t * 1.4, 0.06, 0.55)
		lp += (raw - lp) * k
		var s := lp * 1.5 * env
		s += sin(TAU * 120.0 * pitch * t) * 0.22 * env
		out[i] = clampf(s, -1.0, 1.0)
	var w := AudioStreamWAV.new()
	w.format = AudioStreamWAV.FORMAT_16_BITS
	w.mix_rate = rate
	w.stereo = false
	var b := PackedByteArray()
	b.resize(n * 2)
	for i in n:
		b.encode_s16(i * 2, int(out[i] * 32767.0))
	w.data = b
	return w