Xy-pic User's Guide

## 2.6 Changing the target

It is possible to overwrite a target with another by appending something of the form `*`object to it. This has the effect of typesetting the object at the current position, thus effectively on top of the target, and then use what was typeset as the target.

A target may also have its position changed by one of the following constructions:

- `+`vector or `-`vector which changes the target to be a zero-sized one at the position obtained by adding or subtracting the vector to its center, or
- `!`vector which moves the center of the target by the vector;

where a vector should have the form

- , where are TeX dimensions, is the vector with those coordinates,
- the following "corner offsets" of a target are vectors as shown:

  (they must be specified in upper case), and

- `/`d dimen`/` is the vector going dimen in the particular direction d which can be either the eight simple ones in section 1.6, empty to denote that the current direction (the last direction of an arrow) should be used, or one of the following:

  `va(``)` | absolute angle
  d`:a(``)` | relative angle in degrees
  d`:(`x,y`)` | relative vector
  d`^` / d`_` | short for `:a(90)` / `:a(-90)`

  where the d in the last four may be empty to denote the "current direction."

- `0` is the zero vector.

Many, many more possibilities are described in the reference manual [8].

#### Exercise 11.

What is the difference between a target t and the target t`+0`?

Answer.

Xy-pic User's Guide