/[editor]/freecam/freecam.lua

-- state variables

local speed = 0

local strafespeed = 0

local rotX, rotY = 0,0

local velocityX, velocityY, velocityZ



-- configurable parameters

local options = {

	invertMouseLook = false,

	normalMaxSpeed = 2,

	slowMaxSpeed = 0.2,

	fastMaxSpeed = 12,

	smoothMovement = true,

	acceleration = 0.3,

	decceleration = 0.15,

	mouseSensitivity = 0.3,

	maxYAngle = 188,

	key_fastMove = "lshift",

	key_slowMove = "lalt",

	key_forward = "forwards",

	key_backward = "backwards",

	key_left = "left",

	key_right = "right",

	key_forward_veh = "accelerate",

	key_backward_veh = "brake_reverse",

	key_left_veh = "vehicle_left",

	key_right_veh = "vehicle_right"

}



local controlToKey = {

	["forwards"] = "w",

	["backwards"] = "s",

	["left"] = "a",

	["right"] = "d",

	["accelerate"] = "w",

	["brake_reverse"] = "s",

	["vehicle_left"] = "a",

	["vehicle_right"] = "d",

}



local mouseFrameDelay = 0



local mta_getKeyState = getKeyState

function getKeyState(key)

	if isMTAWindowActive() then

		return false

	end

	if key == "lshift" or key == "lalt" or key == "arrow_u" or key == "arrow_d" or key == "arrow_l" or key == "arrow_r" then

		return mta_getKeyState(key)

	end

	if isPedDead(localPlayer) then

		-- We must use getKeyState when dead we also have to hope they're using WASD

		return mta_getKeyState(controlToKey[key])

	else

		-- We can use getControlState

		return getControlState(key)

	end

end



-- PRIVATE



local function freecamFrame ()

    -- work out an angle in radians based on the number of pixels the cursor has moved (ever)

    local cameraAngleX = rotX

    local cameraAngleY = rotY



    local freeModeAngleZ = math.sin(cameraAngleY)

    local freeModeAngleY = math.cos(cameraAngleY) * math.cos(cameraAngleX)

    local freeModeAngleX = math.cos(cameraAngleY) * math.sin(cameraAngleX)

    local camPosX, camPosY, camPosZ = getCameraMatrix()



    -- calculate a target based on the current position and an offset based on the angle

    local camTargetX = camPosX + freeModeAngleX * 100

    local camTargetY = camPosY + freeModeAngleY * 100

    local camTargetZ = camPosZ + freeModeAngleZ * 100



	-- Calculate what the maximum speed that the camera should be able to move at.

    local mspeed = options.normalMaxSpeed

    if getKeyState ( options.key_fastMove ) then

        mspeed = options.fastMaxSpeed

	elseif getKeyState ( options.key_slowMove ) then

		mspeed = options.slowMaxSpeed

    end

	

	if options.smoothMovement then

		local acceleration = options.acceleration

		local decceleration = options.decceleration

	

	    -- Check to see if the forwards/backwards keys are pressed

	    local speedKeyPressed = false

	    if ( getKeyState ( options.key_forward ) or getKeyState ( options.key_forward_veh ) ) and not getKeyState("arrow_u") then

			speed = speed + acceleration 

	        speedKeyPressed = true

	    end

		if ( getKeyState ( options.key_backward ) or getControlState ( options.key_backward_veh ) ) and not getKeyState("arrow_d") then

			speed = speed - acceleration 

	        speedKeyPressed = true

	    end



	    -- Check to see if the strafe keys are pressed

	    local strafeSpeedKeyPressed = false

		if ( getKeyState ( options.key_right ) or getKeyState ( options.key_right_veh ) ) and not getKeyState("arrow_r") then

	        if strafespeed > 0 then -- for instance response

	            strafespeed = 0

	        end

	        strafespeed = strafespeed - acceleration / 2

	        strafeSpeedKeyPressed = true

	    end

		if ( getKeyState ( options.key_left ) or getKeyState ( options.key_left_veh ) ) and not getKeyState("arrow_l") then

	        if strafespeed < 0 then -- for instance response

	            strafespeed = 0

	        end

	        strafespeed = strafespeed + acceleration / 2

	        strafeSpeedKeyPressed = true

	    end



	    -- If no forwards/backwards keys were pressed, then gradually slow down the movement towards 0

	    if speedKeyPressed ~= true then

			if speed > 0 then

				speed = speed - decceleration

			elseif speed < 0 then

				speed = speed + decceleration

			end

	    end



	    -- If no strafe keys were pressed, then gradually slow down the movement towards 0

	    if strafeSpeedKeyPressed ~= true then

			if strafespeed > 0 then

				strafespeed = strafespeed - decceleration

			elseif strafespeed < 0 then

				strafespeed = strafespeed + decceleration

			end

	    end



	    -- Check the ranges of values - set the speed to 0 if its very close to 0 (stops jittering), and limit to the maximum speed

	    if speed > -decceleration and speed < decceleration then

	        speed = 0

	    elseif speed > mspeed then

	        speed = mspeed

	    elseif speed < -mspeed then

	        speed = -mspeed

	    end

	 

	    if strafespeed > -(acceleration / 2) and strafespeed < (acceleration / 2) then

	        strafespeed = 0

	    elseif strafespeed > mspeed then

	        strafespeed = mspeed

	    elseif strafespeed < -mspeed then

	        strafespeed = -mspeed

	    end

	else

		speed = 0

		strafespeed = 0

		if getKeyState ( options.key_forward ) or getKeyState ( options.key_forward_veh ) then

			speed = mspeed

		end

		if getKeyState ( options.key_backward ) or getKeyState ( options.key_backward_veh ) then

			speed = -mspeed

		end

		if getKeyState ( options.key_left ) or getKeyState ( options.key_left_veh ) then

			strafespeed = mspeed

		end

		if getKeyState ( options.key_right ) or getKeyState ( options.key_right_veh ) then

			strafespeed = -mspeed

		end

	end



    -- Work out the distance between the target and the camera (should be 100 units)

    local camAngleX = camPosX - camTargetX

    local camAngleY = camPosY - camTargetY

    local camAngleZ = 0 -- we ignore this otherwise our vertical angle affects how fast you can strafe



    -- Calulcate the length of the vector

    local angleLength = math.sqrt(camAngleX*camAngleX+camAngleY*camAngleY+camAngleZ*camAngleZ)



    -- Normalize the vector, ignoring the Z axis, as the camera is stuck to the XY plane (it can't roll)

    local camNormalizedAngleX = camAngleX / angleLength

    local camNormalizedAngleY = camAngleY / angleLength

    local camNormalizedAngleZ = 0



    -- We use this as our rotation vector

    local normalAngleX = 0

    local normalAngleY = 0

    local normalAngleZ = 1



    -- Perform a cross product with the rotation vector and the normalzied angle

    local normalX = (camNormalizedAngleY * normalAngleZ - camNormalizedAngleZ * normalAngleY)

    local normalY = (camNormalizedAngleZ * normalAngleX - camNormalizedAngleX * normalAngleZ)

    local normalZ = (camNormalizedAngleX * normalAngleY - camNormalizedAngleY * normalAngleX)



    -- Update the camera position based on the forwards/backwards speed

    camPosX = camPosX + freeModeAngleX * speed

    camPosY = camPosY + freeModeAngleY * speed

    camPosZ = camPosZ + freeModeAngleZ * speed



    -- Update the camera position based on the strafe speed

    camPosX = camPosX + normalX * strafespeed

    camPosY = camPosY + normalY * strafespeed

    camPosZ = camPosZ + normalZ * strafespeed

	

	--Store the velocity

	velocityX = (freeModeAngleX * speed) + (normalX * strafespeed)

	velocityY = (freeModeAngleY * speed) + (normalY * strafespeed)

	velocityZ = (freeModeAngleZ * speed) + (normalZ * strafespeed)



    -- Update the target based on the new camera position (again, otherwise the camera kind of sways as the target is out by a frame)

    camTargetX = camPosX + freeModeAngleX * 100

    camTargetY = camPosY + freeModeAngleY * 100

    camTargetZ = camPosZ + freeModeAngleZ * 100



    -- Set the new camera position and target

    setCameraMatrix ( camPosX, camPosY, camPosZ, camTargetX, camTargetY, camTargetZ )

end



local function freecamMouse (cX,cY,aX,aY)

	--ignore mouse movement if the cursor or MTA window is on

	--and do not resume it until at least 5 frames after it is toggled off

	--(prevents cursor mousemove data from reaching this handler)

	if isCursorShowing() or isMTAWindowActive() then

		mouseFrameDelay = 5

		return

	elseif mouseFrameDelay > 0 then

		mouseFrameDelay = mouseFrameDelay - 1

		return

	end

	

	-- how far have we moved the mouse from the screen center?

    local width, height = guiGetScreenSize()

    aX = aX - width / 2 

    aY = aY - height / 2

	

	--invert the mouse look if specified

	if options.invertMouseLook then

		aY = -aY

	end

	

    rotX = rotX + aX * options.mouseSensitivity * 0.01745

    rotY = rotY - aY * options.mouseSensitivity * 0.01745

	

	local PI = math.pi

	if rotX > PI then

		rotX = rotX - 2 * PI

	elseif rotX < -PI then

		rotX = rotX + 2 * PI

	end

	

	if rotY > PI then

		rotY = rotY - 2 * PI

	elseif rotY < -PI then

		rotY = rotY + 2 * PI

	end

    -- limit the camera to stop it going too far up or down - PI/2 is the limit, but we can't let it quite reach that or it will lock up

	-- and strafeing will break entirely as the camera loses any concept of what is 'up'

    if rotY < -PI / 2.05 then

       rotY = -PI / 2.05

    elseif rotY > PI / 2.05 then

        rotY = PI / 2.05

    end

end



-- PUBLIC



function getFreecamVelocity()

	return velocityX,velocityY,velocityZ

end



-- params: x, y, z  sets camera's position (optional)

function setFreecamEnabled (x, y, z)

	if isFreecamEnabled() then

		return false

	end

	

	if (x and y and z) then

	    setCameraMatrix ( x, y, z )

	end

	addEventHandler("onClientRender", root, freecamFrame)

	addEventHandler("onClientCursorMove",root, freecamMouse)

	setElementData(localPlayer, "freecam:state", true)

	

	return true

end



-- param:  dontChangeFixedMode  leaves toggleCameraFixedMode alone if true, disables it if false or nil (optional)

function setFreecamDisabled()

	if not isFreecamEnabled() then

		return false

	end

	

	velocityX,velocityY,velocityZ = 0,0,0

	speed = 0

	strafespeed = 0

	removeEventHandler("onClientRender", root, freecamFrame)

	removeEventHandler("onClientCursorMove",root, freecamMouse)

	setElementData(localPlayer, "freecam:state", false)

	

	return true

end



function isFreecamEnabled()

	return getElementData(localPlayer,"freecam:state")

end



function getFreecamOption(theOption, value)

	return options[theOption]

end



function setFreecamOption(theOption, value)

	if options[theOption] ~= nil then

		options[theOption] = value

		return true

	else

		return false

	end

end



addEvent("doSetFreecamEnabled", true)

addEventHandler("doSetFreecamEnabled", root, setFreecamEnabled)



addEvent("doSetFreecamDisabled", true)

addEventHandler("doSetFreecamDisabled", root, setFreecamDisabled)



addEvent("doSetFreecamOption")

addEventHandler("doSetFreecamOption", root, setFreecamOption)