## Feature #305

### Oblique maps UTM/cartesian coordinates (-Jx)

Status: | New | Start date: | 2013-06-06 | |
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Priority: | Normal | Due date: | ||

Assignee: | - | % Done: | 0% | |

Category: | - | |||

Target version: | - | |||

Platform: |

**Description**

I would like to have oblique maps in cartesian (UTM) coordinates, without havign to reproject data (typically large data sets, and reprojecting may be confusion).

As the data are in UTM coordinates, I use -Jx (cartesian) with a given

scale. Rotating this over a certain angle does not change the scale.

Then, the area for the map would not be just -Rx1/x2/y1/y2, but rather

something like -Rx1/y1/x2/y2/x3/y3 (which is a major change to the

general syntax of GMT) with (x,y)i i=1:3 three out of four border

coordinates for the rotated box; or -Rxll/yll/xur/yur/alpha with {ll =

"lower left"; ur = "upper right", realizing that upper right y may fall

below lower left y in fact} the box coordinates of the rotated figure,

and alpha a rotation angle to be applied. An example is attached.

Maarten