In GIMP, a layer is not always the same size as the image it belongs to. It might be smaller or it might be larger, in which case some parts of it are hidden. The scale its contents.
command displays a dialog in which you can set the dimensions for the active layer. This command changes the dimensions of the layer, but it does notWhen the dialog is displayed, the original dimensions of the active layer are shown. You can change them by using the two text boxes. If these boxes are linked together with a chain, the width-to-height ratio is automatically maintained. If you break the chain by clicking on it, you can set the dimensions independently of each other.
The default unit of measurement is pixels. You can change this by using the drop-down menu. For instance, you might use a «%» of the current size.
By default, the resized layer is placed in the upper left corner of the image. Here, you can set the offset of the upper left corner of the layer relative to the same corner of the image. The default unit of measurement is pixels, but you can change it by using the drop-down menu. You can also place the layer in the center of the image by clicking on the
button.