6.7. Drop Shadow

6.7.1. Overview

图 17.120. Example for the Drop Shadow filter

Example for the Drop Shadow filter

Original image

Example for the Drop Shadow filter

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.

6.7.2. Activate the filter

You can find this filter in the image menu menu through FiltersLight and ShadowDrop Shadow….

This filter is normally disabled. You must add an Alpha channel to your image to use it.

6.7.3. Options

图 17.121. Drop Shadow filter options

Drop Shadow filter options

Presets, Preview, Split view
[注意] 注意

These options are described in 第 2 节 “Common Features”.

X, Y

The layer containing the drop shadow will be moved horizontally by X pixels, vertically by Y pixels. So, X and Y offset determine where the shadow will be placed in relation to the image. High values make the imaginary source of light look like it's far away in horizontal or vertical direction, and low values will make it look closer to the image.

The offsets may be negative, leading to a shadow on the left of the selection if offset X < 0, or above the selection if offset Y < 0.

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.

Blur radius

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.

Color

The shadow may have any color. Just click on the color swatch, and select a color when the color selector pops up or use the eye-dropper.

Opacity

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

6.7.4. 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!

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. Menus/Layer/Crop to content.

  6. Menus/Layer/Layer 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. Menus/Layer/Crop to content.

  7. Menus/Layer/Layer 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.