Pass an object and/or camera number to the functions to facilitate basic mouse and keyboard movement.

I made this program so I could pass it along to other projects. Users should call function InitializeMovement() before the main loop, and call either function MoveCamera(CamNo) for just a free floating camera or function MoveToon(ToonNo, CamNo) to control an object with a follow camera. With Toon Movement, hold the Left Mouse Button to move the camera around the toon without turning the toon. Hold the Right Mouse Button to turn the toon itself. Hold both buttons to move the object forward. The arrow keys will also move the object/camera. I used scancodes to map the arrowkeys, so that the defaults can be changed. There is a full set of Get and Set functions for all the variables. Note that this program does not do anything with collisions. Probably a lot of this kind of code out there, but let me know if it is useful.

                                    ` This code was downloaded from The Game Creators
                                    ` It is reproduced here with full permission
                                    ` http://www.thegamecreators.com
                                    
                                    `Toon and Camera movement functions

`*** Test parameter declarations ***
`camno = 0
`toon = 1

`*** Direction constants ***
#constant _STOP = 0
#constant _FORWARD = 1
#constant _BACK = 2
#constant _RIGHT = 3
#constant _LEFT = 4

`*** Global variables used by CamToonMovement ***
global movespeed as float
global upperlimit as integer
global lowerlimit as integer
global zoomdistance as integer
global zoominterval as float
global maxzoom as integer
global minzoom as integer
global currentzoom as integer
global toonmoving as byte
global FKey as byte
global BKey as byte
global LKey as byte
global RKey as byte

`*** Test objects ***
`make object cube toon,100
`make object plain 100,1000,1000
`xrotate object 100, 90

`do
`   MoveToonWithMouse(toon, camno, movespeed, upperlimit, lowerlimit, zoominterval, maxzoom, minzoom)
`   MoveToonWithKeyboard(toon, movespeed)
`   Diagnose(toon, camno, movespeed, upperlimit, lowerlimit, zoominterval, maxzoom, minzoom)
`loop
`end

`*** Call this function to initialize all variables ***
function InitializeMovement()
   movespeed = 0.1
   upperlimit = 270
   lowerlimit = 90
   zoomdistance = 500
   zoominterval = 1.0
   maxzoom = 1000
   minzoom = 0
   currentzoom = zoomdistance
   toonmoving = _STOP
   FKey = 200
   BKey = 208
   LKey = 203
   RKey = 205
endfunction

`*** Call this function in main loop to control camera only ***
function MoveCamera(camno)
   `*** Reset movement ***
   toonmoving = _STOP

   MoveCameraWithMouse(camno)
   MoveWithKeyboard()

   if toonmoving = _FORWARD
      move camera camno, movespeed
   endif

   if toonmoving = _BACK
      move camera camno, -movespeed
   endif

   if toonmoving = _LEFT
      move camera left camno, movespeed
   endif

   if toonmoving = _RIGHT
      move camera right camno, movespeed
   endif
endfunction

`*** Sub-function controlling the camera with mouse ***
function MoveCameraWithMouse(camno)
   `*** If no Mouse Buttons are pressed, soak mousemove(), (prevents jerkiness)
   if mouseclick() = 0
      y = mousemovey()
      x = mousemovex()
   endif
   `*** Turn Camera if Right Mouse Button is pressed ***
   if mouseclick() = 2
      PointCameraUsingMouse(camno)
   else
      hide mouse
   endif
   `*** Move and Turn Camera if both mouse buttons are pressed ***
   if mouseclick() = 3
      PointCameraUsingMouse(camno)
      toonmoving = _FORWARD
   else
      hide mouse
   endif
endfunction

`*** Sub-function adjusting the angle of the camera ***
function PointCameraUsingMouse(camno)
   `*** Get current camera angles ***
   XcurrentAngle# = camera angle x(camno)
   YcurrentAngle# = camera angle y(camno)
   `*** Calculate the new angle based on mouse movement ***
   XnewAngle# = wrapvalue(XcurrentAngle# + mousemovey())
   YnewAngle# = wrapvalue(YcurrentAngle# + mousemovex())

   `*** Ensure XnewAngle is within upper and lower limit ***
   TestX#=WrapValue(XnewAngle#-180)
   if TestX# > (lowerlimit+180) then XnewAngle#=lowerlimit
   if TestX# < (upperlimit-180) then XnewAngle#=upperlimit

   `*** Rotate camera ***
   xrotate camera camno, XnewAngle#
   yrotate camera camno, YnewAngle#
endfunction

`*** Call this function in Main Loop to control selected toon and camera with both mouse and keyboard ***
function MoveToon(toon, camno)
   `*** Reset movement ***
   toonmoving = _STOP

   MoveToonWithMouse(toon, camno)
   MoveWithKeyboard()

   if toonmoving = _FORWARD
      move object toon, movespeed
   endif

   if toonmoving = _BACK
      move object toon, -movespeed
   endif

   if toonmoving = _LEFT
      move object left toon, movespeed
   endif

   if toonmoving = _RIGHT
      move object right toon, movespeed
   endif
endfunction

`*** Sub-function for controlling toon with mouse ***
function MoveToonWithMouse(toon, camno)
   `*** If no Mouse Buttons are pressed, soak mousemove(), (prevents jerkiness)
   if mouseclick() = 0
      camlock = 0
      y = mousemovey()
      x = mousemovex()
   endif

   `*** Free spin camera around Toon when left mouse button pressed ***
   if mouseclick() = 1
      camlock = 0
      hide mouse
      PointCameraUsingMouse(camno)
   else
      show mouse
   endif

   `*** Turn Toon if Right Mouse Button is pressed ***
   if mouseclick() = 2
      camlock = 1
      hide mouse
      PointToonWithMouse(toon, camno)
   else
      show mouse
   endif

   `*** Move and Turn Toon if both mouse buttons are pressed ***
   if mouseclick() = 3
      camlock = 1
      hide mouse
      PointToonWithMouse(toon, camno)
      toonmoving = _FORWARD
   else
      show mouse
   endif
   FollowCam(toon, camno, camlock)
   FollowCamZoom(camno)
endfunction

`*** Sub-function adjusting look direction for toon ***
function PointToonWithMouse(toon, camno)
   `*** Turn Toon in same direction as camera
   yrotate object toon, camera angle y(camno)
   `*** Get current toon angles ***
   XcurrentAngle# = camera angle x(camno)
   YcurrentAngle# = object angle y(toon)

   XnewAngle# = wrapvalue(XcurrentAngle# + mousemovey())
   YnewAngle# = wrapvalue(YcurrentAngle# + mousemovex())

   `*** Ensure XnewAngle is within upper and lower limit ***
   TestX#=WrapValue(XnewAngle#-180)
   if TestX# > (lowerlimit+180) then XnewAngle#=lowerlimit
   if TestX# < (upperlimit-180) then XnewAngle#=upperlimit

   yrotate object toon, YnewAngle#
   xrotate camera camno, XnewAngle#
endfunction

`*** Sub-function keeping the camera following the toon ***
function FollowCam(toon,camno,camlock)
   `*** Set the camera to follow the toon and face the same direction ***
   tX#= object position x(toon)
   tY#= object position y(toon)
   tZ#= object position z(toon)
   tA#= object angle y(toon)

   position camera camno,tX#,tY#,tZ#
   `*** If camera is not free spinning, set camera angle same as toon angle
   if camlock = 1
      yrotate camera tA#
   endif
endfunction

`*** Sub-function controlling camera zoon ***
function FollowCamZoom(camno)
   `*** Camera zoom function on toon ***
   mz = mousemovez()
   if mz <> 0
      zoomdistance = zoomdistance-(mz/zoominterval)
      if zoomdistance > maxzoom then zoomdistance = maxzoom
      if zoomdistance < minzoom then zoomdistance = minzoom
   endif

   If currentzoom < zoomdistance
      currentzoom = currentzoom + 1
   endif

   If currentzoom > zoomdistance
      currentzoom = currentzoom - 1
   endif

   move camera camno, -currentzoom
endfunction

`*** Sub-function controlling movement with keyboard ***
function MoveWithKeyboard()
   KeyCode = scancode()
   if KeyCode = FKey
      toonmoving = _FORWARD
   endif

   if KeyCode = BKey
         toonmoving = _BACK
   endif

   if KeyCode = LKey
         toonmoving = _LEFT
   endif

   if KeyCode = RKey
         toonmoving = _RIGHT
   endif
endfunction

`*** Get functions ***
function GetMoveSpeed()
   ms = movespeed
endfunction ms

function GetUpperLimit()
   ul = upperlimit
endfunction ul

function GetLowerLimit()
   ll = lowerlimit
endfunction ll

function GetZoom()
   zoom = zoomdistance
endfunction zoom

function GetZoomInterval()
   zi = zoominterval
endfunction zi

function GetMaxZoom()
   mz = maxzoom
endfunction mz

function GetMinZoom()
   mz = minzoom
endfunction mz

function GetCurrentZoom()
   cz = currentzoom
endfunction cz

`*** Set functions ***
function SetMoveSpeed(ms as float)
   movespeed = ms
endfunction

function SetUpperLimit(ul as integer)
   upperlimit = ul
endfunction

function SetLowerLimit(ll as integer)
   lowerlimit = ll
endfunction

function SetZoom(zoom)
   zoomdistance = zoom
endfunction

function SetZoomInterval(zi as float)
   zoominterval = zi
endfunction

function SetMaxZoom(mz as integer)
   maxzoom = mz
endfunction

function SetMinZoom(mz as integer)
   minzoom = mz
endfunction

function SetCurrentZoom(cz as integer)
   zoomdistance = cz
   currentzoom = cz
endfunction

function SetFKey(key as byte)
   FKey = key
endfunction

function SetBKey(key as byte)
   BKey = key
endfunction

function SetLKey(key as byte)
   LKey = key
endfunction

function SetRKey(key as byte)
   RKey = key
endfunction