6.3. SuperNova

6.3. SuperNova
	6. Filtry efekty se světlem

6.3.1. Overview

Obrázek 17.107. Applying example for the Supernova filter

Original image

Filter „Supernova“ applied

This filter creates a big star reminding a supernova. It works with RGB and GRAY images. Light effect decreases according to 1/r where r is the distance from star center.

6.3.2. Activating the Filter

This filter is found in the main menu under Filters → Light and Shadow → Supernova….

6.3.3. Options

Obrázek 17.108. „Supernova“ filter options

Presets, „Input Type“, Clipping, Blending Options, Preview, Split view

	Poznámka
	These options are described in 2 – „Common Features“.

Center X, Center Y

You can use input boxes to set horizontal (X) and vertical (Y) coordinates of Supernova center. You can also click and drag the supernova center in preview.

Poloměr

This is radius of the Supernova center: the upper limit seems to be unlimited. When you increase the value, you increase the number of central white pixels according to r*r (1, 4, 9, …).

Radius is represented by a horizontal line in preview, with a cross at end. You can click and drag this cross to set radius.

Number of spokes

Počet paprsků supernovy (1-1024). Kqaždý pixel ve středu supernovy vysílá jeden pixel silné paprsky. Tyto paprsky se více méně překrývají, což způsobuje třpytivý efekt při pohybu tímto posuvníkem.

Random hue

Color rays at random. (0-360) value seems to be a range in HSV color circle.

Color

Kliknutím na barevné pole otevřete standardní dialog pro výběr barvy.

You also have a color picker. When it is selected, the mouse pointer goes with a square on image: it's the color sample whose size you can modify in the GEGL operation window under Toolbox.

Hnízdo náhodných čísel

Filter effect is made at random. You can change seed.