Orient a Grid

Use the 3D View > Orient a Grid menu option (IMGORIENT3D GX) to set up or modify the orientation of a grid in 3D space.

Orient a Grid dialog options

Grid

The name of the grid to be oriented.

Script Parameter: IMGORIENT3D.GRID

Orientation

Select "Plan" or "Section". Plan grids plot horizontally in the 3D view. Section grids plot vertically or at a dip determined by the "Section dip" value below, with the direction of their Y-axis determined by the "Section azimuth" value below.

Script Parameter: IMGORIENT3D.ORIENTATION: 0: Plan, 1: Section

Reference point

The grid must be "anchored" at a location in 3D space. This option determines what this anchor point will be. There are three options (note: "top", "bottom" and "left" refer to locations on the grid as it would normally be viewed in a plan map on the screen):

Grid axis origin. This is distinct from the bottom left corner of the grid. It is the location in space of the point (0, 0) in grid coordinates, and may be far off the grid itself. For a plan grid, normally these values would left as 0, 0 because the location of the grid is contained in the grid itself. All that would be left to specify is the vertical location of the grid: "Reference Z (Elevation)".

Grid top left corner. If selected, this will put the top left corner of the grid at the entered reference point.

Grid bottom left corner. If selected, this will put the bottom left corner of the grid at the entered reference point.

Grid top centre. If selected, this will put the reference point at the top centre of the grid. If this is confusing, think of it this way:

If you select a reference point on the grid (one of the last three options), then the (X, Y, Z) reference point location is where you want to put that grid location in space.

See also the "Default button" topic below.

Script Parameter: IMGORIENT3D.REFTYPE: 0: Grid axis origin; 1: Grid top left corner; 2: Grid bottom left corner; 3: Grid top centre point

Ref X (Easting)

Ref Y (Northing)

Ref Z (Elevation)

The grid reference point to anchor the grid in 3D space. See the Reference Point options above.

Script Parameter: IMGORIENT3D.REFX, REFY and REFZ.

Section azimuth

For section views, the grid "X" axis direction, measured in degrees clock-wise from North (the 3D "Y" axis). Rotation of plan grids is not currently implemented in this GX, and all plan grids are oriented with their "X" and "Y" axes parallel to the "X" and "Y" axes in space.

Script Parameter: IMGORIENT3D.AZIMUTH

Section dip

For section views, the angle measured from the horizontal, looking down the grid from the uppermost edge. A "plan" grid has a dip of 0.0. A section grid must have a dip greater than 0.0, and 90 degrees means a vertical section.

Normally, dip cannot be greater than 90 degrees, but in this implementation, dip values up to (but not including) 180 degrees are valid, and refer to grids rotated past the vertical and back up toward horizontal. This makes sense if you consider the dip to be the clockwise rotation of the grid about the grid’s X axis (or about a line which is parallel to the grid’s X axis).

Script Parameter: IMGORIENT3D.DIP

[Default]

When a grid already has an orientation, then this GX opens up displaying the current orientation values, converted to the last selected Reference Point. However, the user may have entered the original grid orientation using one of the other Reference Point options. To recover those values, select the desired Reference Point (e.g. "Top left corner") and click the "Default" button. The reference location is recalculated to the values for the selected Reference Point, and should then match exactly what was typed in in the original case.

Pushing the "Default" button does NOT alter the current grid location; it just updates the reference point location, based on the current selection of the reference point.

Application Notes

If you find that the reference point location values of a grid which already possesses an orientation are not what you remember setting them to, it may be because the last Reference Point selection for this GX was not the same reference point used when the grid orientation was first defined. See the notes above about the Reference point and Reference point location in the Default button, which explains why this might be so, and how to recover the original values.