Command: modify

Syntax

modify { <elist> ... } {
    <element>=<value> {, <element>=<value> ...
    ...
}

Description

Modify attributes of entities.

Parameters

• <elist>
  A group/entity list defining which entities are to be modified. If omitted, the current contents of the these group are modified.

• <element>
  An entity structure element name whose value is to be changed. The element should be one which has read/write capability. An array specification may be appended.

• <value>
  The new value for element of the appropriate type, e.g. numeric, point etc. Arrays of values are not permitted.

Switches

• -ef=<filter>
  A filter to be applied to all entities within <elist>, further qualifying which entities are to be modified. If omitted, the filter current_filter is used.

Notes

<element>=<value> phrases may be specified one per input line, or on the same input line separated by commas.

Sub-entities of compounds may be modified in isolation from their parent entities.

An entity can also be modified by a redefinition of its entity structure values.

When entity linestyles are modified (e.g. modify { ls=something } ), only polyline and polygon edges with non-null linestyles are changed, thereby protecting any disjoint edge situations.
If null linestyles need to be changed, the following commands are available:

entity.ls[n]=something;# Change the linestyle of the nth edge of an entity
set entity.ls=something;# Change the linestyles for all edges of an entity
modify_ls group { null => something } # Change null edges for all entities in a group

Examples

Modify the pen color of all entities in the these group.

modify { color=red }

Modify the fill color and linestyle of two entities.

modify fred, my_face {
    fill=blue, ls=dot_dash
}

See Also