6.8. Slagskygge

6.8.1. Oversyn

Figur 17.125. Eksempel på bruk av filteret «slagskygge»

Eksempel på bruk av filteret «slagskygge»

Originalbiletet

Eksempel på bruk av filteret «slagskygge»

Using the GEGL «Drop Shadow»


With this GEGL filter you can add a drop-shadow to an image, a selection or a text. You may choose the color, position, and size of the shadow.

6.8.2. Activating the Filter

This filter is found in the main menu under FiltersLight and ShadowDrop Shadow….

It is available if your image holds an Alpha channel (see Del 7.34, «Legg til alfakanal»). Otherwise, it is disabled.

6.8.3. Innstillingar

Figur 17.126. Innstillingane for filteret «slagskygge»

Innstillingane for filteret «slagskygge»

Presets, «Input Type», Clipping, Blending Options, Preview, Split view
[Notat] Notat

Desse innstillingane er omtalte i Del 2, «Felles eigenskapar».

X, Y

Desse boksane bestemmer kor mange pikslar skyggelaget skal flyttast horisontalt (forskyv X) og vertikalt (forskyv Y). Store tal vil gi lange skyggar, medan små tal gir korte skyggar.

Forskyvinga kan også vere negativ. Med X < 0 vert skyggen flytt mot venstre og med Y < 0 oppover.

Out of sheer curiosity, you can see the drop shadow layer clearly by setting blur radius to 0 and moving the drop shadow with X and Y.

Sløringsradius

After creating the shadow, a Gaussian blur with the specified radius is applied to the shadow layer, resulting in the realistic appearance of the drop shadow.

Grow shape

You can choose the shape that will be used to expand or contract the shadow. The choices should be self explanatory: Circle (default), Square, or Diamond.

Grow radius

The distance to expand the shadow before blurring. A negative value will contract the shadow instead.

Farge

You can choose the color of the shadow here. Just click on the color swatch, and select a color when the color selector pops up, or use the eye-dropper to pick a color from the image.

Dekkevne

Shadow opacity. It defaults to 0.500, but you may select any other value from 0 (full transparency) to 2.00 (full opacity) here.

6.8.4. Using Drop Shadow Filter

This GEGL Drop Shadow filter is surprising: if you apply the filter directly to the image as you do with the legacy filter, you get nothing, unless you have transparent areas in your image.

To get the same result as the legacy filter:

  1. Open your original image.

  2. Open a new image, a little bigger than your original image, filled with transparency.

  3. Copy your original image and paste it into the new image. A floating selection is created in the layer dialog.

  4. Anchor the floating selection.

  5. Select LayerCrop Layers to Content.

  6. Select LayerLayer Boundary Size…: set layer size to the same size than your image and filled with transparency; click on the Center button. Then click on the Resize button.

  7. Open the Drop Shadow dialog: the drop shadow is displayed in the on-canvas preview. You can change the default options values.

  8. Eventually, add a new layer, with the same size as the image and filled with the color you want to give to the background. Move this layer to the bottom of the layer stack.

  9. Click on the OK to apply filter.

Applying filter to a selection:

  1. Open your original image.

  2. Open a new image, the same size as your original image, filled with transparency.

  3. Create the selection

  4. Copy the selection and paste it into the new image. A floating selection is created in the layer dialog.

  5. Anchor the floating selection.

  6. Select LayerCrop Layers to Content.

  7. Select LayerLayer to Image Size (with transparency).

  8. Open the Drop Shadow dialog: the drop shadow is displayed in the on-canvas preview. You can change the default options values.

  9. Eventually, add a new layer, with the same size as the image and filled with the color you want to give to the background. Move this layer to the bottom of the layer stack.

    You can also use your original image as background: undo the selection, copy the image and paste it as new layer in the new image. Move the new layer to the bottom of the layer stack.

  10. Click on the OK to apply filter.

Applying filter to a text:

The procedure is more simple to create a drop shadow for a text: create the text and apply the Drop Shadow filter directly.