Add a New Drawing Plane to a 3D View

A 3D View may contain any number of planes and new planes can be added to any 3D View. In the 3D Viewer, use the Add to 3D > Plane menu option to add a new drawing plane to the current 3D View.

Add a New Drawing Plane to a 3D View dialog options

Name of new plane in 3D view

Enter the name of the new plane to be added to the current 3D View. The new plane is added to the Planes & Surfaces group in the 3D Manager tree.

  • If you enter the name of an existing plane, that plane will be replaced.
  • Plane elevation

    Specify the constant offset from the 3D origin in the direction normal to the new plane coordinate system. The default is zero.

    Surface relief grid (optional)

    You can also select a surface relief grid (optional) if you would like the plane to have relief. Specify the name of the grid file that defines the surface relief.

  • If you do specify a relief grid for the plane, all objects drawn on the plane will only appear where the relief grid has data (non-dummy).
  • Surface Relief Grid dialog options

    This dialog will open if a surface relief grid has been specified in the previous dialog.

    You can accept the default values for the surface relief grid, or specify the parameters as required. Then, click the OK button to add a plane with surface relief to the current 3D View.

    Relief grid

    The name of the relief grid specified in the first dialog.

    Plane elevation

    The plane elevation selected in the previous dialog.

    Relief base

    The base value subtracted from the grid value when converting the grid values to "Z" values in the 3D View coordinate systems. The default is zero.

    If using a non-topographic grid for relief, use the Rescale button to return the minimum data value in the grid.

    The "Z" axis value at a given location on the relief grid is given by: Z = Vertical_offset + (grid_value(X, Y) – Relief_base)*Vertical_Scale

    For true topography, set this value to 0.

    Vertical Scale

    Set the vertical scaling for the relief grid. The default is 1.0.

    If using a non-topographic grid for relief, use the Rescale button to produce a 3D relief plane with a height 20% of the width.

    The "Z" axis value at a given location on the relief grid is given by:

    Z = Vertical_offset +

    (grid_value(X, Y) – Relief_base)*Vertical_Scale

    For true topography, set this value to 1.

    Clip minimum Clip maximum

    The relief grid data can be clipped to the specified minimum and maximum values. The defaults are the limits of the data.

    Grid resolution

    The 3D rendering performance is directly related to how finely the relief surface is resolved. The number you enter here represents the maximum relief grid resolution (in steps of 16) that will be used in either the X or Y direction. The default is 64, but for very detailed grids you may want to increase this to a higher number.

    A resolution of 500 is considered quite high, and a resolution of 1000 is very high. Your choice of resolution will depend of the performance of your computer and the detail present in your relief grid.

  • Images drawn on the relief plane are always resolved to a resolution that is optimal given the pixel resolution of the current view.
  • [Defaults]

    The [Defaults] button resets the grid base and vertical scaling parameters to the "topographic" default values of 0.0 and 1.0. The clip limits are reset to the default values calculated from the relief grid.

    [Rescale]

    The [Rescale] button resets the grid scaling parameters and clip limits to the default values calculated from the relief grid.

    Application Notes

    Draw a Plane in a 3D View

    Once a 3D View exists, you can draw directly onto planes in the 3D Viewer. For example, you may want to draw contours or symbols on a plane. To do this, you need to make the plane the default drawing plane, after which anything you draw will be drawn directly on the plane in the 3D view. Another way to draw on an existing plane is by copying a View or View/Group that already exists in a 2D view on the same map to a plane in the 3D View.

    You can also use the clipboard to cut/copy groups from other maps to the default drawing plane of a 3D view.

    To make a plane the default drawing plane:

    1. Select (highlight) the plane in the 3D Manager tree; the plane is then highlighted in bold. To change the default drawing plane, simply select another plane in the tree.

    2. Run SETDVIEW GX.

    About 3D Views

    3D Views are rendered coarsely when interactively changing the orientation or point of view. When you release the mouse in any of these modes, the objects will be refined in a way that is optimum for the given point of view. The time it takes to refine the picture depends on processor speed, your 3D Graphics capabilities, the complexity of the 3D model being drawn (number of planes, number of groups, relief resolution, etc.), and the amount of RAM on your system.

    3D Views may have clipping areas just like 2D Views. In 3D, the clip area is applied vertically relative to the X,Y coordinate or each plane.