rgl (version 0.100.54)

observer3d: Set the observer location.

Description

This function sets the location of the viewer.

Usage

observer3d(x, y = NULL, z = NULL, auto = FALSE)

Arguments

x, y, z

The location as a 3 vector, using the usual xyz.coords conventions for specification. If x is missing or any coordinate is NA, no change will be made to the location.

auto

If TRUE, the location will be set automatically by rgl to make the whole bounding box visible.

Value

Invisibly returns the previous value.

Details

This function sets the location of the viewer relative to the scene, after the model transformations (scaling, rotation) have been done, but before lighting or projection have been applied. (See par3d for details on the rendering pipeline.)

The coordinate system is a slightly strange one: the X coordinate moves the observer location from left to right, and the Y coordinate moves up and down. The Z coordinate changes the depth from the viewer. All are measured relative to the center of the bounding box (par("bbox")) of the subscene. The observer always looks in the positive Z direction after the model rotation have been done. The coordinates are in post-scaling units.

Examples

# NOT RUN {
example(surface3d)  # The volcano data
observer3d(0, 0, 440) # Viewed from very close up
# }