Interactive 3D View Panning

Enables camera panning in an rgl 3D scene, allowing the user to move the view freely within the graphics window by dragging the mouse with the specified button.

Usage

pan3d(button, dev = rgl::cur3d(), subscene = rgl::currentSubscene3d(dev))

Arguments

button

Integer indicating the mouse button used for panning:

1: left button
2: right button
3: middle button (wheel)

dev

RGL device ID (default rgl::cur3d()).

subscene

Subscene to which the movement is applied (default is the active subscene from rgl::currentSubscene3d()).

Value

No value is returned; the function sets mouse callbacks to pan the 3D view interactively.

Details

By default, rgl only allows rotation and zoom of 3D objects, but not camera translation. This function extends the interaction by enabling the user to translate the entire scene in any direction without altering the model orientation.

Internally, the function uses mouse callbacks via rgl::rgl.setMouseCallbacks(), so that when the mouse button is pressed and dragged, the projection matrix (userProjection) is dynamically updated to simulate smooth movement within the scene.

When the specified button is pressed, the function records the initial cursor position (begin event). During mouse movement (update event), it calculates the relative displacement and applies a translation transformation on userProjection using rgl::translationMatrix(), allowing the camera to move in the drag direction and enabling free movement of the scene in the graphics window.

Note

The original code was developed by Duncan Murdoch as part of the rgl package, where it is not exported. It is included here without modifications to facilitate use within this package.

Author

Duncan Murdoch

Examples

if (FALSE) { # \dontrun{
rgl::open3d()
mesh <- rgl::icosahedron3d()
rgl::shade3d(mesh, col = "lightblue")
pan3d(2) # Activate panning with the right mouse button
} # }