In this representation of extended entity data, the fields are stored with the tags forming part of the attribute names for each of the extended entity entries. The data is stored in a single structure in the FME feature named extended_data. As the extended entity data within AutoCAD is grouped into sections, with each section beginning with an application group code, the extended_data structure itself is also divided into different sections with each section beginning with extended_data{#}. The remainder of the attribute name consists of one of the parameters:
|
Extended Entity Parameter |
Contents |
|
application_name |
The name of the application which the entity data is associated. AutoCAD Code: 1001 |
|
autocad_layer{#} |
The name of the layer the extended data is associated. AutoCAD Code: 1003 |
|
string{#} |
A character string value from 0 to 255 characters in length. AutoCAD Code: 1000 |
|
three_reals{#}.real1 three_reals{#}.real2 three_reals{#}.real3 |
Three real numbers. AutoCAD Code: 1010,1020,1030 |
|
world_position{#}.x world_position{#}.y world_position{#}.z |
Three values represent the x, y, and z components of a world_position value. AutoCAD Code: 1011, 1021, 1031 |
|
world_displacement{#}.x world_displacement{#}.y world_displacement{#}.z |
Three values which represent a world displacement value. AutoCAD Code: 1012, 1022, 1032 |
|
world_direction{#}.x world_direction{#}.y world_direction{#}.z |
Three real values which represent a world direction vector. AutoCAD Code: 1013,1023,1033 |
|
real{#} |
A 64-bit floating point number. AutoCAD Code: 1040 |
|
handle{#} |
AutoCAD handle value. AutoCAD Code: 1005 |
|
distance{#} |
A 64-bit floating point number which represents a distance. AutoCAD Code: 1041 |
|
scale{#} |
A 64-bit floating point number which represents a scaling factor. AutoCAD Code: 1042 |
|
16Bit_integer{#} |
A 16 bit integer value. AutoCAD Code: 1070 |
|
32Bit_integer{#} |
A 32 bit integer value. AutoCAD Code: 1071 |
For example, given the following extended entity data:
1001 C_NODE
1000 CONNOBJ_1=43F4
1000 COUNT=3
1000 CONNOBJ_2=43F3
1000 CONNOBJ_3=43F2
1005 163
1010 45.4
1020 -123.5
1030 0
1001 DPRINT
1000 postscript
The information will be stored in the FME feature using structure notation as follows:
|
Attribute Name |
Attribute Value |
|
extended_data{0}.application_name |
C_NODE |
|
extended_data{0}.string{0} |
CONNOBJ_1=43F4 |
|
extended_data{0}.string{1} |
COUNT=3 |
|
extended_data{0}.string{2} |
CONNOBJ_2=43F3 |
|
extended_data{0}.string(3} |
CONNOBJ_3=43F2 |
|
extended_data{0}.three_reals{0}.real1 |
45.4 |
|
extended_data{0}.three_reals{0}.real2 |
-123.5 |
|
extended_data{0}.three_reals{0}.real3 |
0 |
|
extended_data{0}.handle{0} |
163 |
|
extended_data{1}.application_name |
DPRINT |
|
extended_data{1}.string{0} |
postscript |
Notice how, in this case, the AutoCAD codes are used to form extensions for the attribute names. Also notice how the extended_data items are grouped in the FME feature as they are within the drawing file.