13.6. Planeta pequeño

13.6. Planeta pequeño
	13. Filtros de mapa

13.6.1. Visión general

This filter converts a panorama into a small planet. All images don't fit this filter. The ideal image is a 360° x 180° image, also known as equirectangular image. We will see that it is possible to use normal images also.

13.6.2. Activar el filtro

This filter is found in the image window menu under Filters → Map → Little Planet….

13.6.3. Opciones

Figura 17.295. Opciones del filtro “Planeta pequeño”

Opciones

Ajustes predefinidos, vista previa, dividir vista

	Nota
	Estas opciones se describen en la Sección 2, “Características comunes”.

Pan

Horizontal camera panning. If “Inverse transform” option is checked, the “pan” option moves line of sight horizontally. Else, it works as “Spin” option.

Inclinación

Vertical camera panning. Moves line of sight upwards/downwards.

Girar

Spin angle around camera axis. Rotates planet around line of sight.

Ampliación

Zoom level. Zooms planet in/out.

Transformación inversa

Hacer el trazado inverso, útil para retocar zenith, nadir u otras partes del panorama.

Método de remuestreo

Interpolation methods are described in Interpolación

“Cubic” may give better result.

Recortar

El resultado de aplicar este filtro puede ser una imagen más grande que la original. Con la opción predeterminada Ajustar la capa se redimensionará automáticamente cuanto se necesite cuando se aplique el filtro. Con la opción Recortar el resultado se recortará a los límites de la capa.

13.6.4. Using Little Planet filter with an equirectangular image

	Sugerencia
	You can find free equirectangular images at https://commons.wikimedia.org/wiki/Category:360°_panoramas_with_equirectangular_projection.

_{Ettling_Isar_panorama.jpg by © Simon Waldherr under
CC by-sa 4.0}

GIMP opened this 16000x8000 pixels original image in a 1000x500 px frame at zoom 6.25. This is a screenshot scaled to 600x300 px. Note the empty sky, the horizon perfectly horizontal, the vanishing perspective.

Filtro aplicado

13.6.5. Using Little Planet filter with a normal image

Your panorama rarely satisfies conditions necessary for this filter, especially if you cut it off a larger image. The Little Planet filter brings left and right image sides together, and creates an unwanted sharp limit if sides are different. An uneven horizon gives an irregular circle. A blue empty sky occupying the upper half of the image and a horizontal horizon are perfect. Usually, you will have to prepare your panorama before using filter.

Figura 17.296. Imágenes originales

Imagen panorámica original

Filter applied directly with default options

Wipe sky: with Color Picker, darker blue to toolbox foreground and lighter blue to toolbox background. Rectangular selection of sky including a small part of horizon. In the selection, draw a Gradient from top to bottom.
Select the left border of the image.
Copy the selection and Paste it as New layer.
Q shortcut to open the Align tool.
Click on new layer (superimposed on selection area): new layer limits appear. Align new layer to image right side.
Select>None.
Flip new layer horizontally.

New layer aligned to image right side and flipped: left and right image sides are now the same. Sky wiped out. Horizon horizontalized.
Add a black Layer Mask to new layer.
Apply a black-to-white gradient to layer mask.
Apply Little planet filter.

Figura 17.297. Resultados

Imagen preparada

Filtro aplicado