Parcel data in LandXML
COGO (Coordinate Geometry) Points
You can import LandXML COGO (Coordinate Geometry) points and convert them to AutoCAD points.
Civil engineers create COGO points to locate crucial surveying locations. A COGO point can be a project benchmark
point - a common datum that the entire civil team works off and from which all critical dimensions are located.
NOTE A LandXML file usually contains a large number of COGO points. In most cases, you need only a small set to work
within the drawing. You do not need to import all COGO points, only those that have a special meaning for the drawing.
COGO points are the foundation for any civil engineering or surveying project. In Land Desktop, you can use description
keys to place points in the drawing with symbols on specific layers. When importing a LandXML file you can map
selected points to the appropriate layer.
When a COGO point is imported it is defined by its coordinates in the form of “northing easting” or “northing easting
elevation.”
For example, a COGO point could be represented as:
<CgPOINT NAME="1" DESC="MYPOINT">248.04605951 359.53997314
1.000000</CgPOINT>
.
COGO points on a map
NOTE Autodesk Land Desktop uses two coordinate systems for locating points: X,Y and northing/easting. When you start a
new project, these values all default to 0 so that the Y coordinate is the same as the northing, and the X coordinate is the
same as the easting. Unless you change that in Land Desktop before exporting a drawing to LandXML, the exported northing
value will be identical to Y and the exported easting value will be identical to X.
Surfaces
In most surveying and civil engineering operations, you gather information about elevations to generate surface contours
that represent a model of the ground surface. The surfaces in LandXML are made up of many faces which are either
TINs (Triangular Irregulated Networks) or quadrilaterals. Points or contours are usually a primary part of the original
surface information and are supplemented with break lines and boundaries. You can create a surface in LandXML, and
then import it. It is converted to a Free Form mass element.
In the following cases, importing surfaces can create errors or fail altogether:
■
Surfaces with vertical faces
■
Surfaces with tiny gaps between the individual faces
■
Surfaces with very narrow faces
If the import fails, an error message is displayed on the command line, such as “Failed to create mass element from
terrain.”
132 | Chapter 5 Interoperability with Other Applications
Summary of Contents for 00128-051462-9310 - AUTOCAD 2008 COMM UPG FRM 2005 DVD
Page 1: ...AutoCAD Architecture 2008 User s Guide 2007 ...
Page 4: ...1 2 3 4 5 6 7 8 9 10 ...
Page 40: ...xl Contents ...
Page 41: ...Workflow and User Interface 1 1 ...
Page 42: ...2 Chapter 1 Workflow and User Interface ...
Page 146: ...106 Chapter 3 Content Browser ...
Page 164: ...124 Chapter 4 Creating and Saving Drawings ...
Page 370: ...330 Chapter 6 Drawing Management ...
Page 440: ...400 Chapter 8 Drawing Compare ...
Page 528: ...488 Chapter 10 Display System ...
Page 540: ...500 Chapter 11 Style Manager ...
Page 612: ...572 Chapter 13 Content Creation Guidelines ...
Page 613: ...Conceptual Design 2 573 ...
Page 614: ...574 Chapter 14 Conceptual Design ...
Page 678: ...638 Chapter 16 ObjectViewer ...
Page 683: ...Designing with Architectural Objects 3 643 ...
Page 684: ...644 Chapter 18 Designing with Architectural Objects ...
Page 788: ...748 Chapter 18 Walls ...
Page 942: ...902 Chapter 19 Curtain Walls ...
Page 1042: ...1002 Chapter 21 AEC Polygons ...
Page 1052: ...Changing a door width 1012 Chapter 22 Doors ...
Page 1106: ...Changing a window width 1066 Chapter 23 Windows ...
Page 1172: ...1132 Chapter 24 Openings ...
Page 1226: ...Using grips to change the flight width of a spiral stair run 1186 Chapter 25 Stairs ...
Page 1368: ...Using the Angle grip to edit slab slope 1328 Chapter 28 Slabs and Roof Slabs ...
Page 1491: ...Design Utilities 4 1451 ...
Page 1492: ...1452 Chapter 30 Design Utilities ...
Page 1536: ...1496 Chapter 31 Layout Curves and Grids ...
Page 1564: ...1524 Chapter 32 Grids ...
Page 1611: ...Documentation 5 1571 ...
Page 1612: ...1572 Chapter 36 Documentation ...
Page 1706: ...Stretching a surface opening Moving a surface opening 1666 Chapter 36 Spaces ...
Page 1710: ...Offsetting the edge of a window opening on a freeform space surface 1670 Chapter 36 Spaces ...
Page 1956: ...1916 Chapter 42 Fields ...
Page 2035: ...Properties of a detail callout The Properties of a Callout Tool 1995 ...
Page 2060: ...2020 Chapter 45 Callouts ...
Page 2170: ...2130 Chapter 47 AEC Content and DesignCenter ...
Page 2171: ...Other Utilities 6 2131 ...
Page 2172: ...2132 Chapter 48 Other Utilities ...
Page 2182: ...2142 Chapter 51 Reference AEC Objects ...
Page 2212: ...2172 Chapter 52 Customizing and Adding New Content for Detail Components ...
Page 2217: ...AutoCAD Architecture 2008 Menus 54 2177 ...
Page 2226: ...2186 Chapter 54 AutoCAD Architecture 2008 Menus ...
Page 2268: ...2228 Index ...