The following group codes apply to hatch and MPolygon entities.
Hatch group codes 


Group code 
Description 
100 
Subclass marker (AcDbHatch) 
10 
Elevation point (in OCS) DXF: X value = 0; APP: 3D point (X and Y always equal 0, Z represents the elevation) 
20, 30 
DXF: Y and Z values of elevation point (in OCS) Y value = 0, Z represents the elevation 
210 
Extrusion direction (optional; default = 0, 0, 1) DXF: X value; APP: 3D vector 
220, 230 
DXF: Y and Z values of extrusion direction 
2 
Hatch pattern name 
70 
Solid fill flag (0 = pattern fill; 1 = solid fill); for MPolygon, the version of MPolygon 
63 
For MPolygon, pattern fill color as the ACI 
71 
Associativity flag (0 = nonassociative; 1 = associative); for MPolygon, solidfill flag (0 = lacks solid fill; 1 = has solid fill) 
91 
Number of boundary paths (loops) 
varies 
Boundary path data. Repeats number of times specified by code 91. See Boundary Path Data 
75 
Hatch style: 0 = Hatch “odd parity” area (Normal style) 1 = Hatch outermost area only (Outer style) 2 = Hatch through entire area (Ignore style) 
76 
Hatch pattern type: 0 = Userdefined 1 = Predefined 2 = Custom 
52 
Hatch pattern angle (pattern fill only) 
41 
Hatch pattern scale or spacing (pattern fill only) 
73 
For MPolygon, boundary annotation flag: 0 = boundary is not an annotated boundary 1 = boundary is an annotated boundary 
77 
Hatch pattern double flag (pattern fill only): 0 = not double 1 = double 
78 
Number of pattern definition lines 
varies 
Pattern line data. Repeats number of times specified by code 78. See Pattern Data 
47 
Pixel size used to determine the density to perform various intersection and ray casting operations in hatch pattern computation for associative hatches and hatches created with the Flood method of hatching 
98 
Number of seed points 
11 
For MPolygon, offset vector 
99 
For MPolygon, number of degenerate boundary paths (loops), where a degenerate boundary path is a border that is ignored by the hatch 
10 
Seed point (in OCS) DXF: X value; APP: 2D point (multiple entries) 
20 
DXF: Y value of seed point (in OCS); (multiple entries) 
450 
Indicates solid hatch or gradient; if solid hatch, the values for the remaining codes are ignored but must be present. Optional; if code 450 is in the file, then the following codes must be in the file: 451, 452, 453, 460, 461, 462, and 470. If code 450 is not in the file, then the following codes must not be in the file: 451, 452, 453, 460, 461, 462, and 470 0 = Solid hatch 1 = Gradient 
451 
Zero is reserved for future use 
452 
Records how colors were defined and is used only by dialog code: 0 = Twocolor gradient 1 = Singlecolor gradient 
453 
Number of colors: 0 = Solid hatch 2 = Gradient 
460 
Rotation angle in radians for gradients (default = 0, 0) 
461 
Gradient definition; corresponds to the Centered option on the Gradient Tab of the Boundary Hatch and Fill dialog box. Each gradient has two definitions, shifted and nonshifted. A Shift value describes the blend of the two definitions that should be used. A value of 0.0 means only the nonshifted version should be used, and a value of 1.0 means that only the shifted version should be used. 
462 
Color tint value used by dialog code (default = 0, 0; range is 0.0 to 1.0). The color tint value is a gradient color and controls the degree of tint in the dialog when the Hatch group code 452 is set to 1. 
463 
Reserved for future use: 0 = First value 1 = Second value 
470 
String (default = LINEAR) 