move demo files into subdir demo

1 files changed, 36 insertions, 0 deletions

diff --git a/demo/Camera.gd b/demo/Camera.gd
new file mode 100644
index 0000000..0dc6074
--- /dev/null
+++ b/demo/Camera.gd
@@ -0,0 +1,36 @@
+extends Camera2D
+
+var margin :Vector2
+var window : Vector2
+var map_center : Vector2
+var texture_size : Vector2
+var zoom_boundaries : Vector2
+
+func _ready():
+	margin = Vector2(0, 0)
+
+func configure(w : Vector2, c : Vector2, ts : Vector2) -> void:
+	window = w
+	map_center = c
+	texture_size = ts
+	var zout : float = max((texture_size.x + margin.x) / window.x, (texture_size.y + margin.y) / window.y)
+	zoom_boundaries = Vector2(zout - 0.5, zout)
+	update_camera(0, 0, zoom_boundaries.y)
+
+func update_camera(x : float, y : float, z : float) -> void:
+	if z != 0:
+		zoom.x = clamp(zoom.x + z, zoom_boundaries.x, zoom_boundaries.y)
+		zoom.y = zoom.x
+	position.x += x
+	position.y += y
+	var delta = texture_size + margin - (window * zoom.x)
+	if (delta.x <= 0):
+		position.x = map_center.x
+	else:
+		var dx = int(delta.x / 2)
+		position.x = clamp(position.x, map_center.x - dx, map_center.x + dx)
+	if (delta.y <= 0):
+		position.y = map_center.y
+	else:
+		var dy = int(delta.y / 2)
+		position.y = clamp(position.y, map_center.y - dy, map_center.y + dy)