Global Amiga Experience/globalamigaexperience.iso/graphic/cad/xcad3000/xcdoc/drawdim

Text File | 1995-07-10 | 15.8 KB | 343 lines

   5.11.1 DRAW DIMENSION

The DRAW DIMENSION command is used to draw one or more dimension entities.
The dimension and text parameters are taken from the currently selected
parameters for the viewport or the system default parameters. Any of the
selected or system parameters can be overridden using the DPARAMETERS or
TPARAMETERS modifiers.


   COMMAND FORMAT

The command format for DRAW DIMENSION varies according to the modifiers
used. When the command and the required modifiers have been selected,
entering a colon will result in the 'Loc', 'Ent' or 'View' prompt being
issued:

   #DRAW DIMENSION modifiers :Loc/Ent

      or

   #DRAW DIMENSION modifiers :View

If the current active viewport is the sheet viewport, the 'View' prompt will
be issued if one or more internal viewports exist. The purpose if this
prompt is to enquire if you wish to use a different viewport for
dimensioning. If a viewport is selected, then all dimension values will be
calculated using the scale and units of the identified viewport. The
dimension entities themselves will always be created on the sheet viewport,
but will be related to the dimension viewport.

When the viewport has been selected, a colon must be entered to go on to the
next stage of input. To use the sheet viewport to calculate dimension
values, a colon is entered without selecting one of the other viewports:

   #DRAW DIMENSION modifiers :View x1 :Loc/Ent  ( To select a dimension
                                                viewport ).

      or

   #DRAW DIMENSION modifiers :View :Loc/Ent     ( To use the sheet
                                                viewport ).

Whether or not the next prompt for input is 'Loc' or 'Ent' is dependent on
the type of dimension selected using the TYPE modifier. These differences in
format are described below.


   MODIFIERS

LAYER          Requires a layer number. This will override the current
               active layer.

DEPTH          Requires a depth number. This will override the current
               active depth.

TYPE           The TYPE modifier is used to select the type of dimension
               required. There are seven available dimension types to choose
               from:

                  HORIZONTAL     Used to dimension the horizontal distance
                                 between two points. This is the default
                                 type used if TYPE is omitted.

                  VERTICAL       Used to dimension the vertical distance
                                 between two points.

                  LINEAR         Used to dimension the total distance
                                 between two points.

                  POINT          Used to draw a single point dimension.

                  ANGULAR        Used to dimension an angle.

                  DIAMETRIC      Used to dimension an arc or circle.

                  RADIAL         Used to dimension an arc or circle.

               Each of these dimension types requires a slightly different
               sequence of command input:

                  #DRAW DIMENSION TYPE HORIZONTAL :Loc x1 x2 x3 [x4] [:Loc ]

               Locations 'x1' and 'x2' define the object points of the
               dimension. The dimension value will be obtained from the
               horizontal distance between these two points. Location 'x3'
               defines the y point for the witness line. The optional
               location 'x4' will be used as an origin point for the
               dimension value text if it is entered. ( See fig. 5.75 ). If
               If 'x4' is omitted, the dimension value text will be placed
               automatically. ( See fig. 5.76 and 5.77 ).

               The optional text origin is applicable to all dimension
               types.

                  #DRAW DIMENSION TYPE VERTICAL :Loc x1 x2 x3 [x4] [:Loc ]

               Locations 'x1' and 'x2' define the object points of the
               dimension. The dimension value will be obtained from the
               vertical distance between these two points. Location 'x3'
               defines the x point for the witness line. ( See fig. 5.78 ).

                  #DRAW DIMENSION TYPE LINEAR :Loc x1 x2 x3 [x4] [:Loc ]

               Locations 'x1' and 'x2' define the object points of the
               dimension. The dimension value will be obtained from the
               total distance between these two points. Points 'x1' and 'x2'
               also define the angle of the witness line and leader lines.
               Location 'x3' is used as reference point to place the witness
               line. ( See fig. 5.79 ).

                  #DRAW DIMENSION TYPE POINT :Loc x1 x2 x3 [x4] [:Loc ]

               Location 'x1' defines the object point of the dimension.
               Locations 'x2' and 'x3' define the start and end point of a
               leader line. The dimension value will be obtained from the
               ordinate value of 'x1'. ( See fig. 5.80 ).

                  #DRAW DIMENSION TYPE ANGULAR :Loc x1 x2 x3 x4 [x5] [:Loc ]

               Locations 'x1', 'x2' and 'x3' define the dimension angle.
               The points 'x2' and 'x3' should be entered anticlockwise in
               relation to the angle origin at 'x1'. Location 'x4' defines
               the radius of the witness line as the distance between points
               'x1' and 'x4'. ( See fig. 5.81 ).

                  #DRAW DIMENSION TYPE DIAMETRIC :Ent x1 :Loc x2 [x3]

               Diametric dimensions are always created by referencing an arc
               entity. The dimension value is obtained from the diameter of
               the entity selected by 'x1'. Location 'x2' is used to place
               the witness line. If location 'x2' is inside the radius of
               the arc, then the witness line will be drawn within the
               circumference of the arc or circle. If location 'x2' is
               outside the radius of the arc, then the witness line will be
               from point 'x2' through the middle of the circle. The angle
               of the witness line is obtained by the angle formed between
               the centre of the arc or circle and point 'x2'. No leader
               lines are drawn. The dimension value text will be prefixed
               by the diameter symbol. ( See fig. 5.82 and 5.83 ).

                  #DRAW DIMENSION TYPE RADIAL :Ent x1 :Loc x2 [x3] [:Loc ]

               Radial dimensions are always created by referencing an arc
               entity. The dimension value is obtained from the radius of
               the arc selected by 'x1'. A single line is drawn from the arc
               circumference to the location 'x2'. ( See fig 5.84 ).

ALIGN          The ALIGN modifier is used to align a new dimension with an
               existing dimension. ALIGN can only be used with the dimension
               types HORIZONTAL, VERTICAL, LINEAR and ANGULAR. The command
               format changes when the ALIGN modifier is used:

                  #DRAW DIMENSION ALIGN modifiers :Ent x1 :Loc x2 [:Ent ]

               'x1' is used to select an existing dimension entity. The
               witness line for the new dimension entity will be aligned to
               the witness line of the selected entity. The location of 'x1'
               is also used to obtain the first object point for the
               dimension. Location 'x2' defines the second object point for
               the dimension. If location 'x3' is entered, then this defines
               the origin for the dimension value text. If 'x3' is omitted,
               the dimension value text will be placed automatically. ( See
               fig. 5.85 ).

DPARAMETERS    The DPARAMETERS modifier is used to enter a further set of
               modifiers used to control the dimension parameters.

.SUPPRESSLEAD  This modifier can be used to suppress one or both of the
               dimension leader lines. SUPPRESSLEAD is followed by one of
               four keywords:

                  FIRST    Suppress the first leader line.
                  SECOND   Suppress the second leader line.
                  BOTH     Suppress both leader lines.
                  NONE     Do not suppress any of the leader lines.

               ( See fig. 5.86 ).

.LEADGAP       The LEADGAP modifier is used to define the gap left between
               the start of the leader line and the object point of the
               dimension. If a negeative value is entered, then the leader
               lines will extend beyond the dimension object points. LEADGAP
               should be followed by a real value. ( See fig. 5.87 ).

.LEADEXT       The LEADEXT modifier is followed by a real value used to
               define the distance that each leader line is extended beyond
               the dimension witness line.

.ARROWHEAD     The ARROWHEAD modifier is used to select the type of
               arrowhead to be used for all dimension entities. The modifier
               is followed by one of 5 keywords to select the arrowhead
               type:

                  CLOSED      Use a closed unfilled arrowhead.
                  FILLED      Use a closed filled arrowhead.
                  OPEN        Use an open arrowhead ( < shape ).
                  DASH        Use a diagonal dash as the arrowhead ( /
                              shape ).
                  NONE        No arrowhead will be used.

..LENGTH       Requires a real value to specify the length of the arrowhead
               in the creation viewport units.

...RATIO       Specifies the ratio between the arrowhead length and width.
               If the arrowhead length was entered as 5mm, a ratio of 2.5
               will make the arrowhead width 2mm.

.SCALE         The SCALE modifier can be used to specify a scale factor
               which will be applied to all dimension values.

.UNITS         If this modifier is used, any dimension values will be
               converted from their dimension viewport units to a specified
               units type. The units types that can be entered are:

                  MM       Millimetres.
                  CM       Centimetres.
                  M        Metres.
                  KM       Kilometres.
                  IN       Inches.
                  FT       Feet.
                  ML       Miles.
                  DEFAULT  Use the default units.

.TEXT          The TEXT modifier is used to enter a further set of modifiers
               used to control layout and formatting characteristics for
               dimension text.

..POSITION     This modifier has a number of options to decide how the
               dimension text is positioned relative to the witness line:

                  HORIZONTAL  Always position the text horizontally. ( See
                              fig. 5.88 ).

                  ALIGN       Always align the text with the witness
                              line. ( See fig. 5.89 ).

                              The above 2 options override any selected
                              text angle.

                  MANUAL      Position the text manually. The text angle
                              and justification is taken from the
                              currently selected text parameters.

...BREAK       If the BREAK modifier is used with POSITION options
               HORIZONTAL or ALIGN, then the witness line will be broken to
               fit the dimension value text. ( See fig. 5.90 ).

..DTEXT        The DTEXT modifier can be used to enter a character string
               that will be used as the dimension text instead of the
               actual dimension value. ( See fig. 5.91 ).

..PREFIX       The PREFIX modifier can be used to enter a character string
               that will act as a prefix to any dimension value text. ( See
               fig 5.92 ).

..NOPREFIX     NOPREFIX will cancel any prefix text that may have already
               been selected using the SELECT TEXT command.

..SUFFIX       The SUFFIX modifier can be used to enter a character string
               that will act as a suffix to any dimension value text.

..NOSUFFIX     NOSUFFIX will cancel any suffix text that may have already
               been selected using the SELECT TEXT command.

..PRECISION    The PRECISION modifier is followed by an integer value used
               to define the number of decimal places of precision to use
               when formatting dimension value text. ( See fig. 5.93 ).

..TRAILZERO    TRAILZERO is a toggle use to switch between displaying or
               not displaying any trailing zeros when fromatting dimension
               value text.

..TOLERANCE    The TOLERANCE modifier is used to specify one of 4
               tolerancing formats that can be used with dimensions. The
               modifier is followed by one of 4 keywords:

                  T±    Used to enter a single value for plus and minus
                        tolerances.

                  T+T-  Used to enter two tolerance values; one positive
                        and one negative tolerance.

                  T+    Used to enter a single value for a positive
                        tolerance only.

                  T-    Used to enter a single value for a negative
                        tolerance only.

...VALUE       This modifier is used to specify the tolerance value ( or
               values in the case of T+T- ) for the above modifier.

..FORMAT       The FORMAT modifier is used to select the format for
               dimension values if the dimension viewport units or selected
               units type are imperial - feet or inches. The default is to
               use feet and inches format with decimal fractions: one foot
               six and a half inches would be formatted as " 1'-6.500" ".

...DECIMAL     Will select decimal format for imperial units: one foot six
               and a half inches will be formatted as "1.5416".

...IMPERIAL    Selects the default imperial format. ( See fig. 5.94 ).

....FRACTIONS  Will use fractional values in formatting dimension text
               values for imperial units. The modifier should be followed by
               an integer value defining the lowest denominator to be used
               for fractional values. Unless the FIXED modifier is used, the
               lowest common denominator will be sought; ie, if a value of
               16 is chosen for the FRACTIONS value, 0.5 will be formatted
               as "1/2" and not "8/16". ( See fig. 5.95 ).

               The above example of one foot six and a half inches will
               be formatted as " 1'-6 1/2" ".

.....FIXED     Will used fixed fractions when formatting imperial values.
               The denominator specified under FRACTIONS will always be
               used.

TPARAMETERS    The TPARAMETERS modifier is used to enter a further family
               of modifiers used to control the text parameters and
               appearance.

               See the documentation for the command DRAW TEXT for a full
               description of the modifiers used to control text parameters.

EXPLODE        Specifies that the dimension should be exploded into all of
               its component parts. If this modifier is used, individual
               entities are created as opposed to a single dimension entity.
               This means that each entity that makes up the dimension can
               be edited or referenced in the normal way.

               All of the entities created will be related to each other to
               form a group of equal members.

.UNLINK        If the UNLINK modifier is used in conjunction with EXPLODE,
               the entities that compose the dimension will not be related.

ATTRIBUTE      Used to enter one or more attributes associated with this
               entity. For a full description of the ATTRIBUTE option, see
               the documentation for the command ADD ATTRIBUTE.