Switch slides from screenspace to unit circle space

Makes Curve2D calculations much nicer, at the potential cost of adding multiplies to the Chord path.
Also added an optimisation of sorts for Complex slides.

scripts/NoteHandler.gd

@@ -180,8 +180,9 @@ func make_slide_trail_mesh(note) -> ArrayMesh:
 	var size := GameTheme.sprite_size2 * sqrt(2)
 	var color := GameTheme.COLOR_DOUBLE_SLIDE if note.double_hit else GameTheme.COLOR_SLIDE
 
-	# First we need to determine how many arrows to leave.
+	match note.get_points():
-	var trail_length : int = int(floor(note.get_slide_length() * slide_arrows_per_unit_length))
+		[var positions, var angles]:
+			var trail_length : int = len(positions)
 			vertices.resize(3*trail_length)
 			uvs.resize(3*trail_length)
 			colors.resize(3*trail_length)
@@ -190,10 +191,8 @@ func make_slide_trail_mesh(note) -> ArrayMesh:
 				for j in 3:
 					uvs[i*3+j] = u[j]
 					colors[i*3+j] = Color(color.r, color.g, color.b, (1.0+float(i))/float(trail_length))
-
+				var angle : float = angles[i]
-	for i in trail_length:
+				var offset : Vector2 = positions[i] * GameTheme.receptor_ring_radius
-		var angle : float = note.get_angle((i+1)/float(trail_length))
-		var offset : Vector2 = note.get_position((i+1)/float(trail_length))
 				vertices[i*3] = offset
 				vertices[i*3+1] = offset + polar2cartesian(size, angle+PI*0.75)
 				vertices[i*3+2] = offset + polar2cartesian(size, angle-PI*0.75)
@@ -381,7 +380,7 @@ func _draw():
 					trail_alpha = min(1.0, (position-GameTheme.INNER_NOTE_CIRCLE_RATIO)/(1-GameTheme.INNER_NOTE_CIRCLE_RATIO*2))
 				else:
 					var trail_progress : float = clamp((t - note.time_hit - GameTheme.SLIDE_DELAY)/(note.duration - GameTheme.SLIDE_DELAY), 0.0, 1.0)
-					var star_pos : Vector2 = note.get_position(trail_progress)
+					var star_pos : Vector2 = note.get_position(trail_progress) * GameTheme.receptor_ring_radius
 					var star_angle : float = note.get_angle(trail_progress)
 					make_star_mesh(mesh, star_pos, 1.33, star_angle)
 					if note.progress != INF:
@@ -417,8 +416,8 @@ func _input(event):
 
 	for i in range(len(active_slide_trails)-1, -1, -1):  # Iterate backwards as we are potentially deleting entries
 		var note = active_slide_trails[i]
-		var center = note.get_position(note.progress)
+		var center = note.get_position(note.progress) * GameTheme.receptor_ring_radius
-		var center2 = note.get_position(min(note.progress+0.06, 1.0))
+		var center2 = note.get_position(min(note.progress+0.06, 1.0)) * GameTheme.receptor_ring_radius
 		if ((pos - center).length_squared() < Rules.SLIDE_RADIUS2) or ((pos - center2).length_squared() < Rules.SLIDE_RADIUS2):
 			note.progress += 0.09
 			if note.progress >= 1.0:

singletons/Note.gd

@@ -123,8 +123,8 @@ class NoteSlide extends NoteBase:  # Fancy charts have naked slides which necess
 	func update_slide_variables():
 		match slide_type:
 			Note.SlideType.CHORD, Note.SlideType.CHORD_TRIPLE:
-				values.start = GameTheme.RADIAL_UNIT_VECTORS[column] * GameTheme.receptor_ring_radius
+				values.start = GameTheme.RADIAL_UNIT_VECTORS[column]
-				values.end = GameTheme.RADIAL_UNIT_VECTORS[column_release] * GameTheme.receptor_ring_radius
+				values.end = GameTheme.RADIAL_UNIT_VECTORS[column_release]
 				values.angle = (values.end - values.start).angle()
 			Note.SlideType.ARC_CW:
 				values.start_a = GameTheme.RADIAL_COL_ANGLES[column]
@@ -138,23 +138,42 @@ class NoteSlide extends NoteBase:  # Fancy charts have naked slides which necess
 					values.end_a -= TAU
 			Note.SlideType.COMPLEX:
 				values.curve2d = Curve2D.new()
-				values.curve2d.bake_interval = 0.005  # TODO: play around with this
+				values.curve2d.bake_interval = 0.1  # TODO: play around with this
 
 	func get_position(progress: float) -> Vector2:
 		match slide_type:
 			Note.SlideType.CHORD, Note.SlideType.CHORD_TRIPLE:
 				return lerp(values.start, values.end, progress)
-			Note.SlideType.ARC_CW:
+			Note.SlideType.ARC_CW, Note.SlideType.ARC_ACW:
 				var circle_angle : float = lerp(values.start_a, values.end_a, progress)
-				return polar2cartesian(GameTheme.receptor_ring_radius, circle_angle)
+				return polar2cartesian(1.0, circle_angle)
-			Note.SlideType.ARC_ACW:
-				var circle_angle : float = lerp(values.start_a, values.end_a, progress)
-				return polar2cartesian(GameTheme.receptor_ring_radius, circle_angle)
 			Note.SlideType.COMPLEX:
 				progress *= values.curve2d.get_baked_length()
-				return values.curve2d.interpolate_baked(progress) * GameTheme.receptor_ring_radius
+				return values.curve2d.interpolate_baked(progress)
 		return Vector2(0.0, 0.0)
 
+	func get_points(per_radius: float = 10.0) -> Array:
+		# Returns PoolVector2Array positions, PoolRealArray angles
+		match slide_type:
+			Note.SlideType.COMPLEX:
+				var interval = 1.0/per_radius
+				if values.curve2d.bake_interval != interval:
+					values.curve2d.set_bake_interval(interval)  # Setting this, even to the same value triggers a new bake
+				var positions: PoolVector2Array = values.curve2d.get_baked_points()
+				var angles = []
+				for i in len(positions)-1:
+					angles.append((positions[i+1]-positions[i]).angle())
+				positions.remove(0)  # Don't need an arrow pointing at the start position
+				return [positions, PoolRealArray(angles)]
+			_:
+				var trail_length : int = int(floor(get_slide_length() * per_radius))
+				var angles = []
+				var positions = []
+				for i in trail_length:
+					angles.append(get_angle((i+1)/float(trail_length)))
+					positions.append(get_position((i+1)/float(trail_length)))
+				return [PoolVector2Array(positions), PoolRealArray(angles)]
+
 	func get_angle(progress: float) -> float:
 		match slide_type:
 			Note.SlideType.CHORD, Note.SlideType.CHORD_TRIPLE: