Mastering the OrbitMode T1.4

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I. Fixes
Fix 1 - My Fix - Make the orbit camera able to zoom in through script.
Fix 2 - Chris Shark (Nov 24, 2005) - Fix jittery movement when following moving objects.
Fix 3 - My Fix - Make it possible to orbit a point rather than an object.
Fix 4 - Orion Elenzil (Jul 03, 2006) - Fix initial OrbitMode camera orientation.

II. Examples
Option 1 - Refer to document - Use two keyboard keys to move the camera in and out.
Option 2 - Refer to document - Use the mouse y axis plus the right button to move the camera in and out.
Quickly Set the Orbit Mode - One example of setting up the orbit camera.

III. Notes About the Camera
God Mode - Diablo style view
Orbit Mode - Fly around an object always looking at it
Static Mode - A fixed camera
Free Fly Mode - Standard editing camera
First Person Mode - Standard First Person Mode
Third Person Mode - Standard Third Person Mode


I. Fixes
Fix 1
There are two options to completing this task. The first would be to make a setCurOrbitDist() console function. The second (the one I outline) is to make mCurOrbitDist accessible to the the script directly. This is done with camera speed and I have seen no ill effects by doing the same with mCurOrbitDist.
camera.h
1.1 - at line 53

// FIX: OrbitMode - 1.1 - This is now a static variable so that it can be exposed
//      to the script.
// F32 mCurOrbitDist;
   static F32 mCurOrbitDist;

camera.cc
1.2 - at line 48

// FIX: OrbitMode - 1.2 - Initialize the variable
F32 Camera::mCurOrbitDist = 0;

1.3 - void Camera::consoleInit() - around line 456

// FIX: OrbitMode - 1.3 - Expose the mCurOrbitDist to the script
   Con::addVariable("Camera::curOrbitDist",TypeF32,&mCurOrbitDist);

1.4 - void Camera::validateEyePoint(F32 pos, MatrixF *mat) - around line 584

EDIT: another option is to pass mCurOrbitDist into the pos variable for validateEyePoint but I haven't tested this.

// FIX: OrbitMode - 1.4 - The default calculation gives a distance base
   // upon mMaxOrbitDist and mMinOrbitDist to decide the distance of the
   // camera from the object.  Now that the mCurOrbitDist is exposed to the
   // script we can make a new calculation based upon the mCurOrbitDist.
   // validateEyePoint is called twice from within camera.cc and both times
   // pos is passed in as 1.0f.  Looking at further calculations it appears
   // that pos is a scaler value so any calculation involving mCurOrbitDist
   // will work.  The added lines also make sure to limit the value of
   // mCurOrbitDist within the parameters set up by calling the setOrbitMode
   // function from within script.
   // pos *= mMaxOrbitDist - mMinOrbitDist;
      if(mCurOrbitDist > mMaxOrbitDist)
         mCurOrbitDist = mMaxOrbitDist;
      if(mCurOrbitDist <= mMinOrbitDist)
         mCurOrbitDist = mMinOrbitDist + 0.1f; // <-- 0.1 is your choice to add.
      pos *= mCurOrbitDist; // <-- put any calculation with mCurOrbitDist.

Now that you made those fixes you can recompile and set up a key binding to change $Camera::curOrbitDist in the scripts.
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Fix 2
camera.cc
2.1 - void Camera::interpolateTick(F32 dt) - around line 280

// FIX: OrbitMode - 2.1 - was getting jittery movement for moving objects
// setRenderPosition(mPosition, rot);
// validateEyePoint(1.0f, &mRenderObjToWorld);
   setPosition(mPosition, rot);
   validateEyePoint(1.0f, &mObjToWorld);

2.2 - void Camera::interpolateTick(F32 dt) - around line 285

// FIX: OrbitMode - 2.2 - was getting jittery movement for moving objects
// setRenderPosition(pos,rot);
   setPosition(pos,rot);

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Fix 3
camera.cc
3.1 - ConsoleMethod( Camera, setOrbitMode ...) - around line 479

//  Either make the changes listed or just comment out the old function and past this one in
ConsoleMethod( Camera, setOrbitMode, void, 7, 8, "(GameBase orbitObject, transform mat, float minDistance,"
                                           " float maxDistance, float curDistance, bool ownClientObject)"
              "Set the camera to orbit around some given object.\n\n"
              "@param   orbitObject  Object we want to orbit.\n"
              "@param   mat          A set of fields: posX posY posZ aaX aaY aaZ aaTheta\n"
              "@param   minDistance  Minimum distance to keep from object.\n"
              "@param   maxDistance  Maximum distance to keep from object.\n"
              "@param   curDistance  Distance to set initially from object.\n"
              "@param   ownClientObj Are we observing an object owned by us?")
{
   Point3F pos;
   AngAxisF aa;
   F32 minDis, maxDis, curDis;

   GameBase *orbitObject = NULL;

// FIX: OrbitMode - 3.1 - Move the line that parses the transformation
   dSscanf(argv[3],"%g %g %g %g %g %g %g",
       &pos.x,&pos.y,&pos.z,&aa.axis.x,&aa.axis.y,&aa.axis.z,&aa.angle);
// END

   if(Sim::findObject(argv[2],orbitObject) == false)
   {
      Con::warnf("Invalid object. Attempting to orbit point.");
   // FIX: OrbitMode - 3.2 - Check to see if we have a valid point
      if(!bool(pos))
      {
               // Tell the player that we have an invalid point
         Con::warnf("Invalid point. Setting Fly Mode.");
         object->setFlyMode();
         return;
      }
   // END
   }

// FIX:  OrbitMode - 3.3 - comment out the line of code that we moved.
// dSscanf(argv[3],"%g %g %g %g %g %g %g",
//     &pos.x,&pos.y,&pos.z,&aa.axis.x,&aa.axis.y,&aa.axis.z,&aa.angle);
// END
   minDis = dAtof(argv[4]);
   maxDis = dAtof(argv[5]);
   curDis = dAtof(argv[6]);

   object->setOrbitMode(orbitObject, pos, aa, minDis, maxDis, curDis, (argc == 8) ? dAtob(argv[7]) : false);
}

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Fix 4
camera.cc
4.1 - void Camera::setOrbitMode([...]) - around line 573

// FIX: OrbitMode - 4.1 - initial orientation fix
// Point3F dir;                                        //<- new variable
// tempMat.getColumn(1, &dir);          //<- grabbing garbage data
   EulerF dir = tempMat.toEuler();       //<- computes a Euler for tempMat

II. examples
Quickly Set the Orbit Mode
default.bind.cs

// This should be a command to the server but for
// a simple example this will do

// Track if we are in orbitMode
$orbitMode = false;

// Toggle the Orbit Mode by pushing a button
function toggleOrbitMode(%val)
{
   // If the button is pushed
   if (%val)
   {
      // If we ar not in orbit mode
      if (!$orbitMode)
      {
         // The camera can be a bit fickle so we have to
         // pay attention to what we are doing with it

         // Put the camera object into orbit mode around the player
         // This mode takes a game base object, transform, min distance,
         // max distance, current distance, and if the client owns the object
         LocalClientConnection.camera.setOrbitMode(
            LocalClientConnection.player,
            LocalClientConnection.player.getTransform(),
            2, 20, 10, 0);
         // We need to tell the client that the camera object is now the
         // camera versus the player object
         LocalClientConnection.setCameraObject(
            LocalClientConnection.camera);
         // We want to be able to control the camera so we will tell the client
         // the control object is the camera
         LocalClientConnection.setControlObject(
            LocalClientConnection.camera);
         // we have just set up the orbit mode so set the variable to true.
         $orbitMode = true;
      }
      else
      {
         // We are in orbit mode so we want to set things back to normal.
         // Set the camera into fly mode
         LocalClientConnection.camera.setFlyMode();
         // Tell the client we want to view the scene through the player.
         LocalClientConnection.setCameraObject(
            LocalClientConnection.player);
         // Tell the client we want to control the player again.
         LocalClientConnection.setControlObject(
            LocalClientConnection.player);
         // We are now out of orbit mode.
         $orbitMode = false;
      }
   }
}

// Middle Mouse Button
moveMap.bind(mouse0, button1, toggleOrbitRadiusChange);

config.cs

moveMap.bind(mouse0, "button2", toggleOrbitMode);

III. Notes About the Camera

The camera that comes with Torque 1.4 can be a bit funky at times. I will try to list some possible combinations and how to get things working again if you happen to mess with something.

God mode
camera.setOrbitMode() - Set the orbit mode to be above the player
client.setControlObject(player) - Set the control object to the player
client.setCameraObject(camera) - Set the camera object to the camera

The result will be a fixed camera above the player. It's not going to orbit because we are controlling the player. (at least not without some extra altering)

Orbit Mode
camera.setOrbitMode(object, object.getTransform(), min, max, cur, 0)
client.setCameraObject(camera)
client.setControlObject(camera)

The result will be a camera that orbits around the object. You will not be controlling the player

Static Mode
camera.setFlyMode()
client.setCameraObject(camera)
client.setControlObject(player)
client.setFirstPerson(false)
EDIT: camera.setTransform(object.getTransform()) - I believe there is more proper because it marks the information as dirty so the ghosts are updated.

The result will be a camera that cannot be controlled and will be at whatever position you tell it to be at.

EDIT: See File for more information. Also if anybody needs me to, I'll change the format to PDF... however Open Office is free and a nice substitute for Microsoft Office