Banded Software :: Development For The Senses

Rem Project: MultiCameras Tutorial
Rem Created: 4/24/2003 9:37:56 PM
Rem Created By: Alasdair Macleod (newbi2basic)
Rem Enhanced Comments: Dan Heenan (Silent)
Rem ***** Main Source File *****

Rem Use Timer() as our Randomize Seed will almost ensure that
Rem each run will result in a different set of numbers. It is
Rem good practice to use this anytime you need random numbers
Randomize timer()

Rem Set Display Mode can be set in the Side Control Panel, but
Rem some users may not realise that they've defaulted to some-
Rem thing else, and this will ensure that the screen will show
Rem the same way we originally set it up.
Set display mode 800,600,32

Rem This is the General Game Setup, nearly all games will use
Rem the same style, turning on manual Sync to try and get the
Rem best refresh rate possible, or just to display certain
Rem items whenever we want. The Sync Rate has been set to a
Rem maximum of 30 to ensure that users with 'Super-Computers'
Rem and most other computers will run at the same speed. This
Rem is useful for many reasons, but it mostly to stop the
Rem advantage/disadvantages some users may have. Autocam Off
Rem is used so that the Field Of View(FOV) is not changed by
Rem the loading of media and therefore we will not had a
Rem stretched viewing angle, beyond the normal range of the
Rem eye.
Sync on
Sync rate 30
Autocam off

Rem Set up our World. Certain user will require a different
Rem set of manipulation options for their land/sea, and can
Rem choose which suits them out of an Object or a Matrix.
Rem In this case we are using a simple to create Matrix,
Rem with a size of 1000 units horizontally(X-Axis), and 1000
Rem units 'into the screen'(Z-Axis), this is then split into
Rem 52 tiles by 52 tiles, all equally sized.
Make matrix 1,1000,1000,52,52

Rem We have created our Matrix, now we need to give it some
Rem character. In this case we will use the Random(Rnd)
Rem command to generate a height value between 0 and 13.
Rem This is run in a loop, 1 to 52 in both the X and Z axis
Rem so that each tile is set to the height of that Random
Rem Number, this will give us a 'bumpy' Matrix.
For x = 1 to 52
   For Z = 1 to 52
      Set matrix height 1,x,z,Rnd(13)
   Next z
Next X

Rem This command is simply used to update ANY changes we
Rem have made to our Matrix, in our case it's our height
Rem changes.
Update matrix 1

Rem Here we will create our Multiple Cameras. We run this in
Rem a loop to save on typing, and/or to make out code neater
Rem This loop will create 3 cameras, all with the default
Rem settings.
For i = 1 to 3
   Make camera i
next i

Rem Currently, our newly created cameras are all covering
Rem each other, so we will now set their Viewport, that is,
Rem the area in which our specific camera will render to
Rem the screen. We have to specify the camera number we
Rem want to change the viewport of, and also the left,top,
Rem right, and bottom co-ordinates of the viewing area.
Rem So this code will set, Camera 0 (Default) to the Upper
Rem Left corner of the screen, Camera 1 (User Created) to
Rem the Lower Left, Camera 2 (User Created) to the Upper
Rem Right, and Camera 3 (User Created) to the Lower Right.
Set camera view 0,0,0,400,300
Set camera view 1,0,300,400,600
Set Camera view 2,400,0,800,300
Set Camera view 3,400,300,800,600

Rem We will now re-position each of the cameras, as currently
Rem they are all at the same position (0,0,0). There's not much
Rem to explain here, but we set the X-Axis(Horizontal), Y-Axis
Rem (Vertical), and Z-Axis('Into the Screen'). In general the
Rem Cameras are positioned to show off your scene, and multiple
Rem cameras are positioned in different areas to show it from a
Rem different angle, eg. In a racer you could use your default
Rem camera for normal view, and a second camera for a rear-view
Rem mirror effect.
Position Camera 0,0,15,0
Position Camera 1,0,15,0
Position Camera 2,1000,15,1000
Position Camera 3,1000,15,0

Rem We now start our main loop. This is a Do...Loop loop, where
Rem we will run the code inside forever, unless the user quits
Rem or the Exit command is sent. The rest of the commands will
Rem be explained as we come across them.
Do

   Rem Here will spin the camera on the spot, we are only going to
   Rem rotate on the Y-Axis(Vertical), so we will use the command
   Rem YRotate Camera, rather than the XRotate/ZRotate/Rotate Camera
   Rem command. As we are spinning, we can only spin 360°, so we
   Rem use the Wrapvalue command, as this will automatically 'wrap'
   Rem the value we give it around back to 0+ if we give it a value
   Rem more than 360°. The value we pass it here, is the current
   Rem camera Y angle, plus the speed we want it to rotate at,
   Rem basically how many degrees per frame.
   YRotate Camera 0,Wrapvalue(Camera Angle Y(0) + 1)

   Rem We are now going to rotate Camera 2 (Although it's numbered 1)
   Rem around the Y-axis, but this time based on the horizontal move-
   Rem ment of the mouse, using MouseMoveX(). Here we have to divide
   Rem the value returned by 2, otherwise we will be given a value too
   Rem large resulting in an uncontrollable camera. We will also check
   Rem for a Left Mouseclick using MouseClick(). This function will
   Rem return a value based on which mouse buttons, if any are being
   Rem pressed, in the following way:
   Rem      Returns        Why?
   Rem         0           No Buttons Pressed
   Rem         1           Left Mouse Button
   Rem         2           Right Mouse Button
   Rem         3           Left and Right Buttons (Returned values added)
   Rem         4           Middle Mouse Button
   Rem         5+          Other buttons your mouse may have, although
   Rem                     these are not normally used in games due to
   Rem                     varying configurations.
   YRotate Camera 1,Wrapvalue(Camera Angle Y(1) + (MouseMoveX() / 2.0))
   If MouseClick() = 1 then Move Camera 1,2

   Rem With Camera 3, we will raise and lower it based on the value in
   Rem our height# variable. We will also modify our height# value based
   Rem on the value in our direction variable, this being -1 for going
   Rem down or anything(<> but -1) else for going up. We do a quick check
   Rem before moving the camera to see if we are too high or low and then
   Rem change the direction varible based on the results. We check whether
   Rem the height# is more than(>)50 and if so, change the direction to -1
   Rem we also check for height# being less than(<) 15, and if so, change
   Rem direction to 1, although this doesn't really matter and could be
   Rem anything but -1. After our checks we finally re-position our camera.
   Rem Using Camera Position X(), and Camera Position Z() to retrieve the
   Rem X and Z position of the camera as we are not modifying this, and set
   Rem the Y position to the value of height#.
   If direction <> -1 then height# = height# + 0.5
   If direction = -1 then height# = height# - 0.5
   If height# > 75.0 then direction = -1
   If height# < 15.0 then direction = 1
   Position Camera 2,Camera Position X(2),height#,Camera Position Z(2)

   Rem Our Fourth and Last Camera will be controlled by use using the Arrow
   Rem Keys. Although there is a command in DarkBasic Professional that will
   Rem do this for us, it is more flexible if we use our own code. Using the
   Rem commands Upkey(), Downkey(), Leftkey(), and Rightkey(), we can check
   Rem which of the arrowkeys are currently being pressed. They will return
   Rem 1 if True, or 0 if False. We pass 1 to the Move Camera command so
   Rem that it will move 1 unit in whatever direction it is facing, we pass
   Rem -1 when checking the Downkey so that we move back 1 unit. We are
   Rem again using Wrapvalue and Camera Angle Y() to turn/rotate the camera.
   Rem In the Leftkey() check we use -1 as if you are turning left, you will
   Rem turn Anti-Clockwise. The Rightkey() uses +1 to turn in a clockwise
   Rem direction.
   If Upkey() = 1 then Move Camera 3,1
   If Downkey() = 1 then Move Camera 3,-1
   If Leftkey() = 1 then YRotate Camera 3,Wrapvalue(Camera Angle Y(3) - 1)
   If Rightkey() = 1 then YRotate Camera 3,Wrapvalue(Camera Angle Y(3) + 1)

   Rem This is the end of our loop, here we Sync so that all the changes we
   Rem have made, except for Matrix manipulation are displayed. It is best
   Rem to only have 1 or as little as possible Sync's in your code, as this
   Rem will provide an optimal running rate. This is due to the whole scene
   Rem not having to be rendered over and over. We then get to the loop,
   Rem where the whole process after the Do command is run again. This will
   Rem continue till the user pressed the Escape[Esc] key.
   Sync
Loop