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Introduction to Layers in Gimp

  • Category: Gimp
  • Published: Monday, 05 June 2017 15:18
  • Written by Super User
  • Hits: 449


The “layer” is a vital feature of software such as Gimp. Layers are are powerful and underlie both simple and more complex effects. Time spent understanding layers will not be wasted. This tutorial is an introduction to layers.


A real world analogy for the layer is a sheet of clear plastic sheet. You can write or draw one or more sheets and then stack them one upon another to build up a completed image. Layers work in a similar way but they can also be coloured and hold a variety of image content (eg photos, drawings, writing, shapes etc). The opacity of each layer can be varied allowing controlled visibility of the layers below. Layers can be made visible or invisible with a single mouse click on the layer dialogue.


A simple example:-

Check that Gimp is loaded onto your computer then start the program. The diagram shows that the dialogue to created a new image is found under File>new. Load Gimp and create a new project. The New Image dialogue is found in the File menu, just select the defaults for now.

Gimp screenshot
Creating a new image




Foreground and background colours are controlled from the last entry of the Toobox. Arrows allow the two colours to be swapped about and double clicking either colour leads to a colour selection dialogue.


The new image has one layer by and its default foreground and background colours are white and black. Click on the black backgound square and a colour dialogue will be displayed. Choose something less sombre than black (red perhaps) and use the Select tool to Select All (of that layer). Choose the Bucket tool from the Toolbox. Move the Bucket Tool onto the image and click to change the background colour to red.


The key points of the slide are that the Toolbox is accessible from the the Windows menu. Dockable dialogues such as the layer control are available  under Windows>Dockable dialogues.


You can easily revert to the original black foreground using from the colour select dialogue. This will make our foreground colour black once again.


Create a second layer using New Layer – choose white as the background colour. The image will still be black overall, however, the opacity of the white can be varied using the layer dialogue so allowing more or less of the lower layer to be seen. An opacity of 50% will produce grey image.


Gimp Screenshot
how to mix colour opacities

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