The point (cx,cy) determines the circle's center-point, the point (rx,ry) is a point on the circle's outline and thus defines the radius. The points (ax1,ay1) and (ax2,ay2), in relation to the circle's center-point (cx,cy), determine the start- and end-angle of the arc. If Orientation >= 0, the arc is drawn counter-clockwise from the start-angle to the end-angle. If Orientation < 0, the arc is drawn clockwise.

The point (dx2,dy2) determines the radius of the dimension line. The dimension line is a circular arc and has the same center-point as the circle element to be measured. The points (nx1,ny1) and (nx2,ny2) determine the position and, if applicable, the orientation of the dimension number.

The following texts make up the dimension texts to be displayed, where PreText, NumText and PostText will be connected to one text ("Main dimension text") without separating characters.

Attributes New in Version 2021.0

An arc length dimension may contain attribute data blocks (see MKI_BLOCK_ATTRIBUTE) only of type "local". They must be placed behind all other datablocks. Attributes of types "outline" and "point" must not exist. The total number of local attributes per object is limited to MKI_ATTRIBS_PER_OBJECT.

Specific Usage of Data Block 225

DimFlag,

LineOrientation,

LineDimType

[__int32] Unused.

LineDistMode

[__int32] The value LineDistMode determines how the dimension line's distance to the dimension is calculated. The distance is the difference of the circle's and the dimension line's radius. Possible values are:

MKI_DIMDISTANCE_ARBITRARY

The dimension line passes through the point (dx2,dy2).

MKI_DIMDISTANCE_FIXED

The dimension line has exactly the distance stated in LineDistance. The position of (dx2,dy2) determines on what side it lies.

MKI_DIMDISTANCE_MULTIPLE

The dimension line's distance is a multiple of the value stated in LineDistance, while being as close as possible to (dx2,dy2).

Example

|BlockType|

0,225,0,0,

|TextFont|

0,0,400,"DINDRAFT",

|TextXProperty|

1,1,0,0.0/0.0/0.0,0.0/0.0/0.0,0.0,0,0,

|TextSize1,TextSize2|

5.0,3.5,

|CharDistance,TabDistance,TextMode,TextOrder|

0,4,1,0,

|Precision,Refresh,Centered,Tight,Rotate|

2,1,1,1,0,

|ArrowStart...,ArrowEnd...|

1,0,1,0,

|ExtStartDisplay,ExtEndDisplay,LineDisplay|

1,1,1,

|Orientation,Type,DistMode,Distance|

1,1,0,10.0,0.0,

|System|

This arc length dimension will be lettered with the font "DINLQ", using pen 1. The main dimension has a text size of 5 mm, the tolerances have a text size of 3.5 mm. The dimension number will automatically placed centered and tight to the dimension line, it will be updated automatically.

The dimension line has a fixed distance of 10 mm to the circular arc. Both dimension extension lines will be visible, they are either drawn radially from an edge's end-point to the dimension line or parallel (this depends on settings in the application). At both ends of the dimension line, a filled, non-rotated, triangular arrow will be drawn.

The dimension will be calculated according to the settings in the coordinate system "00: *Standard".

The image above shows an arc length dimension created using the settings described above. The points (cx,cy), (rx,ry), (ax1,ay1) and (ax2,ay2) define the circular arc to be measured. The dimension line has a distance of 10 mm, the point (dx2,dy2) determines its position.

The dimension number was centered and set tight automatically, so the point (nx1,ny1) is irrelevant. As the number is not rotated the point (nx2,ny2) is not used.

Interface Command Sequence

MKI_ObjectOpen, Type = MKI_OBJ_DARCLENGTH

MKI_ObjectAddPoint, Type = MKI_DB_POINT_CENTER

MKI_ObjectAddPoint, Type = MKI_DB_POINT_RADIUS

MKI_ObjectAddPoint, Type = MKI_DB_POINT_ANGLE

MKI_ObjectAddOrient

MKI_ObjectAddPoint, Type = MKI_DB_POINT_ANY

MKI_ObjectAddTextShort, StaticLength = false

MKI_ObjectAddTextShort, StaticLength = true

MKI_ObjectAddTextShort, StaticLength = false

MKI_ObjectAddDimLarge

MKI_ObjectFastInsert

Use the MKI_PARSE_OBJ_DARCLENGTH class to parse the data blocks of such an object in memory.