From a4b7de996b11bfda6dc9e240537f92e68fa72815 Mon Sep 17 00:00:00 2001
From: Mono <mono@nekolize.moe>
Date: Sun, 21 Nov 2021 13:44:46 +0100
Subject: [PATCH] Implemented buggy free hand canvas transform for
 touchscreens.

---
 .../tools/general_use/free_transform.gd       | 51 +++++++++++++++++--
 1 file changed, 48 insertions(+), 3 deletions(-)

diff --git a/addons/summer_day/tool/canvas/tools/general_use/free_transform.gd b/addons/summer_day/tool/canvas/tools/general_use/free_transform.gd
index 5c2a4c0..77defe5 100644
--- a/addons/summer_day/tool/canvas/tools/general_use/free_transform.gd
+++ b/addons/summer_day/tool/canvas/tools/general_use/free_transform.gd
@@ -2,15 +2,60 @@ extends SummerDayTool
 class_name SummerDayFreeTransformCanvasTool
 
 
+var touch_dict = {}
+var initial_touches
+var current_touches
+var initial_transform: Transform2D
+
+
 func _init():
 	priority = 1
 
 
 func _check_for_use(event: InputEvent, tool_context: SummerDayToolContext):
+	if event is InputEventScreenTouch:
+		if event.pressed:
+			touch_dict[event.index] = event.position
+		else:
+			touch_dict.erase(event.index)
+		if touch_dict.size() == 2:
+			initial_transform = tool_context.canvas_state.canvas_transform
+			
+			var keys = touch_dict.keys()
+			initial_touches = [touch_dict[keys[0]], touch_dict[keys[1]]]
+		print(touch_dict)
+	
 	if event is InputEventScreenDrag:
-		return true
+		touch_dict[event.index] = event.position
+		if touch_dict.size() == 2:
+			var keys = touch_dict.keys()
+			current_touches = [touch_dict[keys[0]], touch_dict[keys[1]]]
+			return true
+	
+	return false
 
 func _run(event: InputEvent, tool_context: SummerDayToolContext):
-	var transform := tool_context.canvas_state.canvas_transform
-	transform = transform.translated(event.relative)
+	var jump := Transform2D.IDENTITY
+	
+	# Calculate scale.
+	var initial_distance = initial_touches[0].distance_to(initial_touches[1])
+	var current_distance = current_touches[0].distance_to(current_touches[1])
+	var scale = current_distance / initial_distance
+	
+	# Calculate rotation.
+	var initial_angle = initial_touches[0].angle_to_point(initial_touches[1])
+	var current_angle = current_touches[0].angle_to_point(current_touches[1])
+	var rotation = current_angle - initial_angle
+	
+	jump = jump.scaled(Vector2(scale, scale)).rotated(rotation)
+	
+	# Calculate origin.
+	var transformed_initial_touch = jump.basis_xform(initial_touches[0])
+	var offset = current_touches[0] - transformed_initial_touch
+	
+	print(jump)
+	jump = Transform2D(Vector2.RIGHT, Vector2.DOWN, offset) * jump
+	print(jump)
+	
+	var transform = jump * initial_transform
 	tool_context.canvas_state.canvas_transform = transform