This topic provides a brief guide to the PEN3D's Zoom Window Draw Menu. Scroll down for detailed descriptions.
These options are part of the main menu for PEN3D.
Draw Menu:
Draw menu with selected draw tool checked
The Draw menu contains the options for digitising objects onto the DTM. The objects are placed in logical groups, namely:
| • | ground height, and benches - these are objects that describe the ground height; |
| • | ground cover (environmental and roads) - these are objects that describe the characteristics of the surface covering; |
| • | barriers and reflecting base - these are objects that comprise solid vertical surfaces; |
| • | noise sources - Road, point, line and moving line noise sources; |
| • | receivers - comprise point or area sources. |
Ground Height
The ground height is a line object that has elevation. The height is entered using the elevation edit box.
Bench
The bench is a four sided area object that has elevation. The bench has vertical sides much like a bench in a quarry. The height is entered using the elevation edit box. When the bench option is selected the zoom window toolbar has an extra option when the start digitising button is pressed.
Extra options during bench entry
This option permits either a freeform bench (irregular) or a rectangular bench to be inserted into the DTM.
Ground Cover
The ground cover is split into two sections the first for environmental noise models and the second for CoRTN road traffic models.
Ground Cover should comprise a closed loop and two areas should not intersect/cross. It is acceptable for one area to be fully within the area of the second.
Barriers
Barriers are objects that have a vertical dimension. The height in meters is entered using the elevation edit box.
There are two types of barriers relative and absolute. A relative barrier is one having a height specified relative to the local ground level. An absolute barrier is one having an absolute (RL) height in meters.
Reflecting Base
The reflective base object is a CoRTN only object. It is used to determine the angle of any reflections from the walls. If the reflecting base object is missing then the noise barrier is absorptive. If the reflective base is entered then the barrier becomes reflective. Even terrain can be made reflective by placing a reflective base at the bottom of a cutting.
Noise Sources
There are four types of noise sources, point, line, road and rail. Depending on the type of model selected then the appropriate noise sources will be made available. The height in meters is entered using the elevation edit box.
These objects require additional information other than elevation. After the location of each object has been digitised into the DTM the program requests additional information appropriate to the object.
Receiver
There are two types of receivers, point and calculation box. The height in meters is entered using the elevation edit box.
Point
The point receiver requires a name to be entered as well as the elevation. After the location of each object has been digitised into the DTM the program requests additional information appropriate to the object.
Calculation Box
The calculation box, like the bench, is a four sided area object that has elevation. The calculation box elevation represents a calculation surface (plane) having an elevation parallel to the underlying DTM. The height of the calculation plane is entered using the elevation edit box. When the calculation box option is selected an additional dialog box appears.
The Calculation box shape option permits either a freeform calculation area (irregular) or a rectangular calculation area to be inserted into the DTM.
Extra options during calculation box entry
Point (Offset)
The final receiver option is Point Offset... this option permits receiver points to be digitised close to existing objects.
Calculation point (offset) entry
With this option selected the model searches for the closest relevant object and calculates the height of that object. It then places a calculation point with the selected horizontal and vertical offsets. It automatically numbers using the settings and incrementing by one as each point is digitised. This tool is useful when digitising receptor locations 1 m from building facades.