#93 Slant view movement should be pinned to local altitude

[Anonymous]

When slanting the view by right-click-drag, the crosshair
cursor should behave at all altitudes as it does at sea
level - the view should appear to rotate/slant around the
crosshairs, and the crosshairs should be "pinned" at the
local altitude, not at sea level. When looking at terrain
above sea level, the crosshair position acts as if it is still
at sea level and so it is harder and different to do right-
click-drag at altitude than it is at sea level, the view
moves in a way that is not consistent.

[Nobody/Anonymous]

Logged In: NO

Duplicate / Alternate explanation of [ 1174388 ] Alternate
control mode: First Person / Flying / Tripod

[Nobody/Anonymous]

Logged In: NO

Duplicate of
[ 1174480 ] base view angle & rotation on terrain not sea level

which is posted 9 requests down the page, and only 10 days
ago. Though this request is somewhat better worded. Good
work redundant submitter.

[Denis Flament]

Logged In: YES
user_id=1255815

Said another way : there should be two "crosshairs" : first
like now, which is at displayed position *at sea level*, and
a second to be added, which would be at the same
latitude/longitude but at the elevation of the terrain.

The distance between the two crosshairs would be equal to
the terrain elevation and "visualize" it.

The second crosshair (red cross on this picture
http://df2.free.fr/crosshairs.jpg\) may be use to visualize
the center of rotation on the ground while right-click
dragging, therefore it would respond to this feature request
for the case of heading change.

When the terrain elevation is higher than half of the
screen, and to respond to this request in the case of bank
or tilt angle changes, there should be an option to keep the
second crosshair at the centre of the screen.

When using motion, this option might induce a "shaky"
movement when passing over a valley or a peak... therefore
it would be better to maintain a constant height, or to
filter the height not to follow each terrain variations but
to tend smoothly towards the terrain height.

PS : I don't think this be a duplicate of [ 1174388 ] Alternate
control mode: First Person / Flying / Tripo which asks for a
rotation around the camera position, not around the ground
target.