Added an initial implementation of WWFirstPersonNavigator to the Navigate group.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1298 1c351a6f-456c-4935-88af-207f26c224cf
Made WWNavigator and its implementations implement the WWDisposable protocol.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1299 1c351a6f-456c-4935-88af-207f26c224cf
Made WorldWindView's navigator property settable. Modified WorldWindView to dispose of its navigator when the view itself is disposed.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1300 1c351a6f-456c-4935-88af-207f26c224cf
Added the capability to seamlessly switch between the first person and look at navigators. Refactored the WWNavigator goto animation interface in order to accommodate both the first person and look at navigators. Modified PathFollower to place the navigator at the aircraft position when using a first person navigator.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1301 1c351a6f-456c-4935-88af-207f26c224cf
Modified WWFirstPersonNavigator to support gotoRegionWithCenter:radius.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1302 1c351a6f-456c-4935-88af-207f26c224cf
Repaired an issue where the WWiOS navigator occasionally failed to redraw the view in response to the last update in a sequence of gesture updates.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1303 1c351a6f-456c-4935-88af-207f26c224cf
Modified the WWiOS navigator implementations to eliminate an unnecessary call to Core Location when switching between two navigators.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1304 1c351a6f-456c-4935-88af-207f26c224cf
Modified WWFirstPersonNavigator to improve the responsiveness of one- and two-finger pan gestures.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1305 1c351a6f-456c-4935-88af-207f26c224cf
Added heading, pitch and roll properties to the WWNavigator protocol. Modified WWFirstPersonNavigator and WWLookAtNavigator to correctly handle roll when switching navigators.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1306 1c351a6f-456c-4935-88af-207f26c224cf
Added initializers and setter methods to WWPosition that enable conversion from Core Location coordinates.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1307 1c351a6f-456c-4935-88af-207f26c224cf
Repaired a typo in the documentation for WWMatrix's extractViewingParameters method.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1308 1c351a6f-456c-4935-88af-207f26c224cf
Added methods to WWNavigator that enable setting a position of interest or an region of interest. Modified components in WorldWindExamples to use these methods.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1309 1c351a6f-456c-4935-88af-207f26c224cf
Repaired an exception in WWFirstPersonNavigator's implementation of the position of interest and area of interest methods.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1310 1c351a6f-456c-4935-88af-207f26c224cf
Addd the capability to switch between first person and look at navigators in the WorldWindExamples app. Modified WorldWindExamples to handle navigator switching when location tracking or path following are enabled.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1311 1c351a6f-456c-4935-88af-207f26c224cf
Added a method to WWMath to interpolate between two angles using the shortest path. Modified the navigator implementations to correctly interpolate their heading, tilt and roll values during an animation. Refactored C functions in WWMath as Objective-C class methods.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1312 1c351a6f-456c-4935-88af-207f26c224cf
Modified the WorldWindExample app's path following capability to track the path's current heading.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1313 1c351a6f-456c-4935-88af-207f26c224cf
Repaired an issue where WWSphere throws an exception when its center point is equal to the eye point.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1314 1c351a6f-456c-4935-88af-207f26c224cf
Interim checkin of terrain picking code.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1315 1c351a6f-456c-4935-88af-207f26c224cf
More interim picking changes.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1316 1c351a6f-456c-4935-88af-207f26c224cf
Modified WWTexture, WWElevationImage and WWRetriever to clean up dangling references held after loading or retrieval completes.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@1317 1c351a6f-456c-4935-88af-207f26c224cf