Enhance RopePhysics with improved collision handling and constraint application

Enhances rope physics for collision and constraints.

Improves collision detection by using precise raycasting for all rope segments and updates the response to accurately halt segments at impact.

Introduces an iterative constraint relaxation method that ensures the rope maintains its target total length. This method correctly anchors rope ends and handles coincident segment points for greater stability.

Refactors and enhances rope physics simulation

Refactors rope physics logic, centralizing it into a dedicated module.
Enhances collision detection with precise raycasting for all segments, ensuring segments halt accurately at impact and rebound to prevent phasing.
Introduces an iterative constraint relaxation method to maintain target rope length. This includes spring damping to prevent extreme tension forces on actors and improve stability, particularly for anchored ends.
Adds light rope smoothing to reduce jaggedness and refines rope length management.
Rope rendering now features a color gradient, and debug information is updated.
Adjusts various physics parameters, including segment limits and pull ratios, for improved grappling behavior.

Author: OpenTools-run

Data/Base.rte/Devices/Tools/GrappleGun/Grapple.lua

@@ -27,7 +27,7 @@ function Create(self)
 
     self.limitReached = false
     self.stretchMode = false   -- Alternative elastic pull mode a là Liero
-    self.stretchPullRatio = 0.1
+    self.stretchPullRatio = 0.01 -- How much the rope stretches when pulling in stretch mode
     self.pieSelection = 0  -- 0 is nothing, 1 is full retract, 2 is partial retract, 3 is partial extend, 4 is full extend
 
     self.climbDelay = 8    -- Faster climbing for shorter rope
@@ -48,8 +48,8 @@ function Create(self)
     self.cablespring = 0.15 -- VelvetGrapple constraint stiffness
 
     -- Dynamic rope segment calculation variables
-    self.minSegments = 4   -- Minimum number of segments
-    self.maxSegments = 50  -- Maximum number of segments
+    self.minSegments = 1   -- Minimum number of segments
+    self.maxSegments = 500  -- Maximum number of segments
     self.segmentLength = 12 -- Target length per segment (increased for better performance)
     self.currentSegments = self.minSegments -- Current number of segments
 
@@ -137,11 +137,17 @@ function Update(self)
 					self.lineLength = self.lineVec.Magnitude
 					self.currentLineLength = self.lineLength
 
-					-- Update rope anchor points directly
+					-- Update rope anchor points directly for flight mode
 					self.apx[0] = self.parent.Pos.X
 					self.apy[0] = self.parent.Pos.Y
 					self.apx[self.currentSegments] = self.Pos.X
 					self.apy[self.currentSegments] = self.Pos.Y
+					
+					-- Set all lastX/lastY positions to prevent velocity inheritance from previous mode
+					for i = 0, self.currentSegments do
+						self.lastX[i] = self.apx[i]
+						self.lastY[i] = self.apy[i]
+					end
 				end
 
 				-- Calculate optimal number of segments based on rope length using our module function
@@ -155,75 +161,46 @@ function Update(self)
 					end
 				end
 
-				-- Rope physics simulation using VelvetGrapple approach
-				local cablelength = self.currentLineLength / math.max(1, self.currentSegments) -- Dynamic per-segment length
+				-- Proper rope physics simulation using the RopePhysics module
+				local endPos = self.Pos
 
-				-- Set anchor points and update physics for all segments
-				local i = self.currentSegments
-				-- HANDLE ALL LINE JOINTS (from n down to 0)
-				while i > -1 do
-					if i == 0 or (i == self.currentSegments and self.limitReached == false and (self.actionMode == 1 or self.actionMode > 1)) then
-						-- Anchor points: 0 (player) and n (hook)
-						if i == 0 then -- POINT 0: ANCHOR TO GUN
-							local usepos = self.parent.Pos
-							self.apx[i] = usepos.X
-							self.apy[i] = usepos.Y
-							self.lastX[i] = self.lastPos.X
-							self.lastY[i] = self.lastPos.Y
-						else -- POINT n: ANCHOR TO GRAPPLE if IN FLIGHT
-							local usepos = self.Pos
-							self.apx[i] = usepos.X
-							self.apy[i] = usepos.Y
-							self.lastX[i] = usepos.X
-							self.lastY[i] = usepos.Y
-						end
-					else
-						if not (i == self.currentSegments and self.actionMode == 2) then
-							-- CALCULATE BASIC PHYSICS
-							local accX = 0
-							local accY = 0.05
-
-							local velX = self.apx[i] - self.lastX[i]
-							local velY = self.apy[i] - self.lastY[i]
-
-							local ufriction = self.usefriction
-							if i == self.currentSegments then 
-								ufriction = 0.99
-								accY = 0.5
-							end
-
-							local nextX = (velX + accX) * ufriction
-							local nextY = (velY + accY) * ufriction
-
-							self.lastX[i] = self.apx[i]
-							self.lastY[i] = self.apy[i]
-
-							-- Use physics module for collision handling
-							RopePhysics.verletCollide(self, i, nextX, nextY)
-						end
-						
-						if i == self.currentSegments and self.actionMode == 3 then
-							if self.target and self.target.ID ~= rte.NoMOID then
-								local target = self.target
-								if target.ID ~= target.RootID then
-									local mo = target:GetRootParent()
-									if mo.ID ~= rte.NoMOID and IsAttachable(target) then
-										target = mo
-									end
-								end
-
-								self.lastX[i] = self.apx[i]-target.Vel.X
-								self.lastY[i] = self.apy[i]-target.Vel.Y
-							else    -- Our MO has been destroyed, return hook
-								self.ToDelete = true
-							end
+				-- Choose physics simulation based on rope mode
+				if self.actionMode == 1 then
+					-- Flight mode - keep rope tight and straight
+					RopePhysics.updateRopeFlightPath(self)
+				else
+					-- Attached mode - run full physics simulation
+					RopePhysics.updateRopePhysics(self, startPos, endPos, self.currentLineLength)
+					
+					-- Apply constraints to maintain rope structure and length
+					RopePhysics.applyRopeConstraints(self, self.currentLineLength)
+				end
+				
+				-- Special handling for attached targets (MO grabbing)
+				if self.actionMode == 3 and self.target and self.target.ID ~= rte.NoMOID then
+					local target = self.target
+					if target.ID ~= target.RootID then
+						local mo = target:GetRootParent()
+						if mo.ID ~= rte.NoMOID and IsAttachable(target) then
+							target = mo
 						end
 					end
 
-					-- Get optimized iteration count based on rope conditions
-					local maxIterations = RopePhysics.optimizePhysicsIterations(self)
-
-					i = i-1
+					-- Update hook position to follow the target
+					self.Pos = target.Pos
+					self.apx[self.currentSegments] = target.Pos.X
+					self.apy[self.currentSegments] = target.Pos.Y
+					
+					-- Apply target velocity to the hook anchor for physics continuity
+					self.lastX[self.currentSegments] = self.apx[self.currentSegments] - target.Vel.X
+					self.lastY[self.currentSegments] = self.apy[self.currentSegments] - target.Vel.Y
+				else
+					-- Update hook position from rope physics when not attached to MO
+					if self.actionMode > 1 then -- Hook is stuck to terrain
+						-- Let the rope physics determine hook position constraints
+						self.Pos.X = self.apx[self.currentSegments]
+						self.Pos.Y = self.apy[self.currentSegments]
+					end
 				end
 
 				-- Draw the rope using the renderer module
@@ -236,19 +213,23 @@ function Update(self)
 				local debugPos = self.Pos + Vector(10, -30) -- Define a position for debug text
 				RopeRenderer.showDebugInfo(self, player, debugPos)
 
-				-- Update hook position based on rope physics
+				-- Update lineVec and lineLength based on current positions
+				self.lineVec = SceneMan:ShortestDistance(self.parent.Pos, self.Pos, self.mapWrapsX)
+				self.lineLength = self.lineVec.Magnitude
+
+				-- Update hook position if length limit is reached during flight
 				if self.actionMode == 1 and self.limitReached == true then
 					self.Pos.X = self.apx[self.currentSegments]
 					self.Pos.Y = self.apy[self.currentSegments]
 				end
 
-				self.lineVec = SceneMan:ShortestDistance(self.parent.Pos, self.Pos, self.mapWrapsX)
-				self.lineLength = self.lineVec.Magnitude
-
-				-- Update current line length
+				-- Update current line length based on action mode
 				if self.actionMode == 1 and self.limitReached == false then 
-					-- Always update rope length while in flight
+					-- Always update rope length while in flight - rope should be tight
 					self.currentLineLength = self.lineLength 
+				elseif self.actionMode > 1 then
+					-- When attached, maintain set line length for physics constraints
+					-- currentLineLength should only be updated by player input or automatic climbing
 				end
 
 				-- Check if line length exceeds maximum