5.5. Compàs

Figura 14.174. Eina compàs

Eina compàs

The Measure Tool is used to gain knowledge about pixel distances in your working image. By clicking and dragging the mouse button, you can determine the angle and number of pixels between the point of click and where the mouse pointer is located. The information is displayed on the status bar or can also be displayed in the Info Window.

A common use case for Measure is to calculate the angle of rotation when horizon is uneven on a photo. Since GIMP-2.10.4, you no longer have to perform the rotation manually to straighten horizon: after measuring the angle, just click the new Straighten button.

This button can be used in straightening horizontal or vertical lines up: the starting point comes with a small bar that shows the direction.

Quan es passa el punter del ratolí sobre el punt final, es converteix en un punter en moviment. Llavors, si feu clic podreu reprendre la mesura.

5.5.1. Barra d'estat

La informació es mostra a la Barra d'estat, a la part inferior de la finestra de la imatge:

  • Distància en píxels entre el punt inicial i el punter del ratolí.

  • Angle a cada quadrant, des de 0° a 90°.

  • Coordenades del punter relatives al punt original.

5.5.2. Activació de l'eina

  • You can get to the Measure from the image-menu through: ToolsMeasure,

  • o fent clic a la icona eina: a la caixa d'eines.

5.5.3. Tecles modificadores (per defecte)


While holding down the Shift key, click and drag from an existing endpoint to create a second measurement line from this endpoint. The angle between the two lines will be displayed. Any endpoint can be moved by clicking and dragging. So, you can measure any angle on the image:

Figura 14.175. Shift modifier

Shift modifier

Click on start point and drag following a side of the angle.

Shift modifier

Then, Shift-click on start point and drag following the other side of the angle: you get the value of this particular angle.


Si es manté premuda la tecla Ctrl obliga l'eina compàs a fer angles de 15°.

Ctrl key pressed and click on an end point creates a horizontal guide. The mouse pointer goes with the icon.

In Horizontal or Vertical Orientation modes, Ctrl also toggles between Horizontal and Vertical.


Alt key and click on an end point creates a vertical guide.


Aquesta combinació de tecles i fent clic a una línia de mesura permet moure la mesura.

La combinació de tecles Ctrl+Alt i fent clic a un punt final, crea unes guies verticals i horitzontals.

5.5.4. Opcions

Figura 14.176. Mesura les opcions de l'eina

Mesura les opcions de l'eina

Orientation (Ctrl)

In the Auto mode (default), Straighten will snap to the smallest angle between the measure line and the vertical or horizontal direction. Horizontal and Vertical allow to override this behavior by specifying explicitly what it should be.

Utilitzeu la finestra d'informació

This option will display an Info Window dialog that details the measure tool results. The results are more complete than on the status bar.


Transform, Interpolation, and Clipping are treated in Secció 3.1, “Característiques comunes”. Here is an example for straightening a path:

Original image

Draw path

Make path visible

Draw measure line on the segment you want to straighten


Figura 14.177. Straighten clipping options

Straighten clipping options

Draw measure line

Straighten clipping options

Straighten with Adjust option

Straighten clipping options

Straighten with Clip option

Straighten with Crop to result option

Straighten with Crop with aspect option

Straighten: click on this button to perform straightening.

5.5.5. Superfícies de mesura

No es poden mesurar directament superfícies però podeu utilitzar l'Histograma que dóna el nombre de píxels d'una selecció.