How to Alpha Lock In Affinity Designer

If you have used Procreate, you may be familiar with a feature called Alpha Lock. But if you’ve recently switched to Affinity Designer, you may have noticed that the program lacks this function. So, how can you get the same results without using Alpha Lock in Affinity Designer?

Alpha Lock allows users to add paint and color only to the layer on which Alpha Lock is applied. To do this in Affinity Designer, a new layer must be clipped to the layer that you want to see the painting contained in.

Not all design programs are going to offer the exact same tools and functions. However, there is usually a way to get the same results. Keep reading to learn how to Alpha Lock in Affinity Designer.

What is Alpha Lock?

Before we can get into how to replicate alpha lock in Affinity Designer, you need to understand exactly what it does so that you know which tools you can use to get the results you’re looking for.

Alpha lock is a function in Procreate that allows users to add paint or color to specific elements in a design by containing the paint within that element’s layer. For example, if you wanted to add a pattern to a shape in your design, you would select the layer of the shape, turn on Alpha Lock, and begin coloring.

Replicating Alpha Lock in Affinity Designer

Unfortunately, for those who use Affinity Designer, there is no available Alpha Lock function. However, there are a few workarounds to create the same effect.

The easiest way to replicate Alpha Lock in Affinity Designer is to use layer clipping. Essentially, what this does is position one layer inside another so that the path of the parent layer acts as the boundary for the clipped layer. 

For example, let’s say you have a design with a square that you would like to add a swirled pattern to. To make sure that the design doesn’t bleed onto the background or other elements, you would clip a new layer to the layer that contains the square. The square would act as the parent layer, and the new layer, or child layer, is where you would apply your pattern.

How to Clip Layers Together in Affinity Designer

To create a clipped layer, you will start by creating the layer that will act as your child layer. This could be a blank layer that you will draw in as you go, or you could create your painting beforehand. Either way works.

Next, find the layer or object that will act as the parent layer. Any object can act as a parent layer, so it’s important to make sure that only the layer you want to work with is selected before creating your clipped layer.

To clip the layers together:

  1. Click on the child layer (the layer that will be adding the paint)
  2. Drag and drop it onto the thumbnail of the parent layer.
  3. In the layers panel, you should now see the child layer sitting beneath the parent layer.

Now, anything added to the child layer will be confined by the boundary set by the parent layer.

Using Protect Alpha in Affinity Designer

Another method of confining paint to a certain layer is to use “Protect Alpha.” This is a setting on the Paintbrush Tool that, when checked, keeps the paint on the current layer’s solid areas. This means that no transparent regions can be colored and the paint won’t move into other layers. However, this can only be done when using the Pixel Persona.

To use Protect Alpha:

  1. Switch into Pixel Persona then select the Paint Brush Tool.
  2. Next, on the context menu at the top of the screen, locate Protect Alpha and make sure the box is checked.
  3. Now, click on the layer you would like to paint from the layers panel and start painting. Everything you add will be contained within that layer.

Keep in mind that this is only available for pixel based strokes. If you would like to use this effect with the vector brush tool, it’s best to go with the clipping layer method.

Final Thoughts

If you are one to flip between design programs, it can be a bit frustrating to figure out all of the tools and settings each one has to offer. Hopefully, this guide gave you a clear understanding of how to alpha lock in Affinity Designer. Though there isn’t a simple button like there is in Procreate, this effect can still be done as long as you know what to look for.