Merge pull request #327 from norrbotten/menu-improvement-3dpanning

Menu improvement: Allow user to rotate and zoom the 3d preview models

lua/vgui/acf_panel.lua

@@ -229,17 +229,83 @@ function PANEL:AddCollapsible(Text, State)
 	return Base, Category
 end
 
+-- Lerps linearly between two matrices
+-- This is in no way correct, but works fine for this purpose
+-- Matrices need to be affine, shear is not preserved
+local function LerpMatrix(A, B, t)
+	if not A:IsRotationMatrix() or not B:IsRotationMatrix() then
+		return B
+	end
+
+	t = math.Clamp(t, 0, 1)
+
+	local Pos = A:GetTranslation() * (1 - t) + B:GetTranslation() * t
+
+	-- rotate A angle towards B angle
+	local Ang = A:GetAngles()
+	local A_Dir = A:GetForward()
+	local B_Dir = B:GetForward()
+
+	local Dot = A_Dir:Dot(B_Dir)
+	if Dot < 0.999999 then
+		RotAxis = A_Dir:Cross(B_Dir)
+		RotAxis:Normalize()
+
+		RotAngle = 180 / math.pi * math.acos(Dot)
+		Ang:RotateAroundAxis(RotAxis, RotAngle * t)
+	end
+
+	local Scale = A:GetScale() * (1 - t) + B:GetScale() * t
+
+	local C = Matrix()
+	C:SetTranslation(Pos)
+	C:SetAngles(Ang)
+	C:SetScale(Scale)
+
+	return C
+end
+
+-- Rotates the matrix roll towards zero
+local function RotateMatrixRollToZero(A, t)
+	local Angles = A:GetAngles()
+	Angles:RotateAroundAxis(A:GetForward(), -t * Angles.r)
+
+	local B = Matrix(A)
+	B:SetAngles(Angles)
+
+	return B
+end
+
+-- Returns the distance from P to the closest point on a box
+-- From https://iquilezles.org/articles/distfunctions/
+local function BoxSDF(P, Box)
+	local Q = Vector(math.abs(P.x), math.abs(P.y), math.abs(P.z)) - Box
+
+	local D1 = Vector(math.max(0, Q.x), math.max(0, Q.y), math.max(0, Q.z)):Length()
+	local D2 = math.min(math.max(Q.x, math.max(Q.y, Q.z)), 0)
+
+	return D1 + D2
+end
+
 function PANEL:AddModelPreview(Model, Rotate)
 	local Settings = {
-		Height = 120,
-		FOV    = 90,
+		Height   = 120,
+		FOV      = 60,
+
+		Pitch    = 15,				-- Default pitch angle, camera will kinda bob up and down with nonzero setting
+		Rotation = Angle(0, -35, 0) -- Default rotation rate
 	}
 
 	local Panel    = self:AddPanel("DModelPanel")
 	Panel.Rotate   = tobool(Rotate)
-	Panel.Rotation = Angle(0, -75)
 	Panel.Settings = Settings -- Storing the default settings
 
+	Panel.IsMouseDown = false
+	Panel.InitialMouseOffset = Vector(0, 0)
+	Panel.LastMouseOffset = Vector(0, 0)
+
+	Panel.RotationDirection = 1
+
 	function Panel:SetRotateModel(Bool)
 		self.Rotate = tobool(Bool)
 	end
@@ -256,7 +322,7 @@ function PANEL:AddModelPreview(Model, Rotate)
 
 	function Panel:UpdateModel(Path)
 		if not isstring(Path) then
-			Path = "models/props_junk/PopCan01a.mdl"
+			return self:DrawEntity(false)
 		end
 
 		local Center = ModelData.GetModelCenter(Path)
@@ -273,14 +339,31 @@ function PANEL:AddModelPreview(Model, Rotate)
 
 		local Size = ModelData.GetModelSize(Path)
 
+		local StartMatrix = Matrix()
+
+		-- looks a bit nicer with this
+		if string.find(Path, "engines") ~= nil then
+			StartMatrix:Rotate(Angle(self.Settings.Pitch, 0, 0))
+		elseif string.find(Path, "reciever") ~= nil then
+			StartMatrix:Rotate(Angle(self.Settings.Pitch, 180, 0))
+		else
+			StartMatrix:Rotate(Angle(self.Settings.Pitch, -90, 0))
+		end
+
+		self.RotMatrix = Matrix(StartMatrix)
+		self.TargetRotMatrix = Matrix(StartMatrix)
+
 		self.CamCenter = Center
-		self.CamOffset = Vector(0, Size:Length())
-		self.LastTime  = RealTime()
+		self.CamDistance = 1.2 * math.max(Size.x, math.max(Size.y, Size.z))
+
+		self.BoxSize = Vector(Size) -- Used for zooming
+
+		self.CamDistanceMul = 1
+		self.CamDistanceMulTarget = 1
 
 		self:DrawEntity(true)
 		self:SetModel(Path)
-		self:SetLookAt(Center)
-		self:SetCamPos(Center + self.CamOffset)
+		self:SetCamPos(Center + Vector(-self.CamDistance, 0, 0))
 	end
 
 	function Panel:UpdateSettings(Data)
@@ -290,6 +373,35 @@ function PANEL:AddModelPreview(Model, Rotate)
 		self:SetFOV(Data and Data.FOV or Settings.FOV)
 	end
 
+	function Panel:OnMousePressed(Button)
+		if Button ~= MOUSE_LEFT then return end
+
+		local MouseOffset = Vector(self:ScreenToLocal(input.GetCursorPos()))
+
+		if MouseOffset:WithinAABox(Vector(0, 0, -1), Vector(self:GetWide(), self:GetTall(), 1)) then
+			self.IsMouseDown = true
+			self.InitialMouseOffset = MouseOffset
+			self.LastMouseOffset = MouseOffset
+		end
+	end
+
+	function Panel:OnMouseReleased_impl(Button)
+		if Button ~= MOUSE_LEFT then return end
+
+		self.IsMouseDown = false
+
+		-- Reset target angles
+		self.TargetRotMatrix:SetAngles(Angle(self.Settings.Pitch, self.TargetRotMatrix:GetAngles().y, 0))
+
+		-- Find what direction user was rotating, and keep rotating in the same direction
+		local YawDiff = self.TargetRotMatrix:GetAngles().y - self.RotMatrix:GetAngles().y
+		self.RotationDirection = (YawDiff <= 0) and 1 or -1
+	end
+
+	function Panel:OnMouseReleased(Button)
+		self:OnMouseReleased_impl(Button)
+	end
+
 	function Panel:LayoutEntity()
 		if self.NotDrawn then return end
 
@@ -298,18 +410,61 @@ function PANEL:AddModelPreview(Model, Rotate)
 		end
 
 		if not self.Rotate then return end
-		if not self.CamOffset then return end
+		if not self.RotMatrix then return end
 
-		local Time     = RealTime()
-		local Delta    = Time - self.LastTime
-		local Rotation = self.Rotation * Delta
-		local Offset   = self.CamOffset
+		-- Handle mouse movement
+		if self.IsMouseDown then
+			local MouseOffset = Vector(self:ScreenToLocal(input.GetCursorPos()))
+			local Delta = MouseOffset - self.LastMouseOffset
 
-		Offset:Rotate(Rotation)
+			-- Rotate towards mouse movement
+			local Rotation = Angle(Delta.y * 0.7, -Delta.x, 0) * FrameTime() * 48
 
-		self:SetCamPos(self.CamCenter + Offset)
+			Rotation.p = math.Clamp(Rotation.p, -5, 5)
+			Rotation.y = math.Clamp(Rotation.y, -15, 15)
 
-		self.LastTime = Time
+			self.TargetRotMatrix:Rotate(Rotation)
+
+			self.LastMouseOffset = MouseOffset
+		else
+			-- Spin around like normal when not panning
+			self.TargetRotMatrix:Rotate(self.Settings.Rotation * FrameTime() * self.RotationDirection)
+		end
+
+		-- Lerp rotation towards target
+		local LerpT = math.Clamp(FrameTime() * 4, 0.05, 0.3)
+		self.RotMatrix = LerpMatrix(self.RotMatrix, self.TargetRotMatrix, LerpT)
+
+		-- Rotate roll towards zero when not panning
+		if not self.IsMouseDown then
+			self.RotMatrix = RotateMatrixRollToZero(self.RotMatrix, LerpT * 0.25)
+		end
+
+		-- Compute zoom distance
+		if self.IsMouseDown and input.IsMouseDown(MOUSE_RIGHT) then
+			local DistToBox = BoxSDF(self.RotMatrix * Vector(-self.CamDistance, 0, 0), self.BoxSize)
+			local Fraction = math.pow(1 - DistToBox / self.CamDistance, 0.5)
+
+			self.CamDistanceMulTarget = Fraction
+		else
+			self.CamDistanceMulTarget = 1
+		end
+
+		-- Lerp distance towards target
+		self.CamDistanceMul = self.CamDistanceMul + (self.CamDistanceMulTarget - self.CamDistanceMul) * LerpT * 0.5
+
+		local CamTransform = Matrix()
+		CamTransform:Translate(self.CamCenter)
+		CamTransform:Rotate(self.RotMatrix:GetAngles())
+		CamTransform:Translate(Vector(-self.CamDistance * self.CamDistanceMul, 0, 0))
+
+		self:SetLookAng(CamTransform:GetAngles())
+		self:SetCamPos(CamTransform:GetTranslation())
+
+		-- Mousedown state gets "stuck" if cursor is outside the panel when releasing, so, adding this
+		if self.IsMouseDown and not input.IsMouseDown(MOUSE_LEFT) then
+			self:OnMouseReleased_impl(MOUSE_LEFT)
+		end
 	end
 
 	Panel:UpdateModel(Model)