This tutorial will teach the different techniques we can use to create masks in Clip Studio Paint. Masks are useful tools that streamline work, allowing you to organize and divide the illustration into sections as you wish. There are many different ways to achieve the same result. First, the basic tools provided by the program will be explained, followed by the more complex ones.

Selection

We start with the most fundamental tool for creating a mask, the "selection tool". We access it by clicking on the icon of the rectangle with the dashed outline.

Within the tool, we will find different versions, all related to the selection function. The first two, "rectangle" and "ellipse", allow us to select areas on the canvas using these shapes.

With "lasso", we can make freehand selections, while with "polyline", we will be restricted by the use of straight lines.

Finally, the "selection pen" option acts like a brush that, similar to the "lasso", allows you to freely draw the exact shape you need to select. When used on the canvas, it will appear with a green tint to facilitate viewing what is being delimited. The color will disappear once we have finished the shape. The "erase selection" option acts as an eraser that will serve to deselect the fragments of that shape that we do not want.

Another option to deselect with any of the explained tools is to hold down the "Alt" key while using them. A minus sign will appear at the bottom of the cursor, meaning we are in the deselection function. Conversely, if we want to add more shapes to our selection, we press the "Shift" key. As a result, a plus sign appears at the bottom of the cursor.

 

The selection function is used to create a momentary mask on the canvas where you can only paint within that selection. It is a very useful and fast tool for making large brushstrokes without worrying about going outside the shape.

Auto Select

Clip Studio Paint offers a tool that performs automatic selection, so the program itself detects different shapes on the canvas. To access it, we need to click on the magic wand icon located below the "selection tool".

Inside, we find the options to "refer only to edited layer for selection" and "refer to other layers for selection". They work similarly, the difference being that the first will only detect shapes within the layer we are on, while the other will look for shapes taking into account all visible layers on the canvas. To use the tool, we simply have to click on the shape we want the program to detect so that it proceeds to select it.

 

Like the "selection tool", this function allows us to create a temporary mask quickly and efficiently. While it is active, you can only draw within the selection. In this example, everything except the animal is selected to allow for shading around it.

The "Alt" and "Shift" keys retain the same functions as in the "selection tool".

 

If we wish to paint outside the selection but do not want to cancel it, we can go to the top menu of the interface, under Select > Invert selected area.

Lock Transparent Pixels

We can find this function at the top of the layer menu with an icon consisting of a padlock and a small square of different gray tones. To activate it, we need to place ourselves on the layer we want to use and click on the icon.

This function locks all transparent pixels on the layer, meaning we can only use the areas of the layer where there was previously paint. In this example, the layer with the animal is locked to allow shading without going outside the figure.

In this way, we generate a mask using the layer itself as an indicator of which parts of the canvas we can paint on and which we cannot. With good organization, it is a really useful tool for quickly generating a mask. The big advantage is that we can activate and deactivate it when necessary.

Clip to Layer Below

To find this function, we need to locate the icon composed of two overlapping ovals in the layer menu.

 

When activated, the selected layer appears with a red line to its left, indicating that it is clipped to the layer below. This means that of everything we paint on this layer, only the areas that coincide with the paint on the layer below will be visible. In this example, the animal is shaded using a clipped layer above it.

With this function, we use a layer as a mask for the one above it. Unlike the previous methods where we could only paint within the selected area, with this method, we can paint anywhere on the canvas. However, only the paint that is within the boundaries of the layer used as a mask will be visible.

Layer Mask

This tool can be complex for beginners, but once mastered, it becomes essential for speeding up the drawing process. This tutorial explains its use in detail so that anyone can master it.

 

We start by locating how to activate the function. To do this, we need to go to the icon in the layer menu that appears as a black rectangle with a white circle inside.

By clicking on it, a white layer is created to the right of the selected layer. This is the "layer mask".

As we have already seen with the previous tools, masks serve to delimit which parts of the canvas the paint appears on. In this case, the mask layer on the right is the indicator for these areas. The white parts of this layer will be the areas where the paint appears, while the black parts will be the areas where it will not be visible.

 

The mask automatically appears white, meaning the paint on the left layer is fully displayed. To create black areas - defining the parts we want to be invisible - we need to take the "eraser tool" and erase them within the mask. It is important to click on the mask, not the layer.

When erasing, we can see that, although the paint on the layer remains intact, only the areas allowed by the mask are shown. If we want to correct, it's as simple as taking our preferred brush and painting with white on the mask over the areas we want to make visible again. The example shows how, using the "eraser tool", black areas are generated within the mask that make the paint on the layer disappear. Then, with the pencil tool and using white color, the mask is painted over again to make the drawing on the layer visible again.

An alternative to using the "eraser tool" to generate black areas is to use the color that acts as transparency. This way, we can use any brush to perform the same function as the eraser.

 

If we want to visualize exactly where the black areas of the mask are located on the canvas, we need to click on the mask while pressing the "Alt" key. When doing so, they will appear highlighted with a bluish tint on the canvas. To deactivate this function, simply click the mask again while pressing the "Alt" key.

It is possible to combine the "auto select tool" and the "layer mask" to quickly generate black and white areas. To do this, we need to go to the desired layer, use the "auto select tool", choose the elements we want to be visible - in other words, that constitute the white areas - and click the mask icon to generate one taking into account that selection. In this example, the outside of the animal is selected and a mask is created, which results in the animal being defined as a black area and not visible.

If we want to delete the mask completely, we need to right-click on it and select "Delete Mask". If, on the other hand, we want to combine the layer and the mask so that the paint in the black areas disappears permanently, we need to select the "Apply Mask to Layer" option.

Finally, this checkmark between the layer and the mask indicates that they are linked.

This means that if we use the "move layer" or "free transform" tool - Edit > Transform > Free Transform - it will affect both of them.

Conversely, if we want to modify the layer or the mask individually, we will have to unlink them. To do this, click on the checkmark to make it disappear. Once unlinked, if we click on the layer and use the "move layer" tool, only the content of the layer will be moved. On the other hand, if we click on the mask and use the tool on it, then only the content of the mask will be moved.

As we have seen, the "layer mask" is a very versatile way to organize our illustration. The great advantage of this method is its ability to edit the mask as many times as necessary without losing the paint on the layer.

Quick Mask

This function can be understood as an agile fusion of the "selection tools" with the "layer mask". To access it, we need to go to the top menu, under Select > Quick Mask.

When activated, a new white layer titled "Quick Mask" will appear.

As with the "layer mask", in this layer, we can use any preferred brush or tool to freehand draw what we want to select. It will appear on the canvas with a reddish tint to facilitate viewing what is being delimited.

If desired, we can change the red tint to another color by clicking on the red square located in the layer menu.

To correct brushstrokes, we can use the "eraser tool" or the color that acts as transparency - as explained in the "layer mask" - to erase until we have the exact shape we need.

 

Once we have the precise shape of what we want to select, it's a matter of returning to the top menu, under Select > Quick Mask, to exit the function.

As we can see in the example, the "quick mask" layer no longer appears, and instead we have a selection with the exact silhouette of what was drawn on it. The greatest virtue of this function is undoubtedly its speed, as it works as an instant "layer mask".

Store Selection Area

Finally, the "store selection area" function will be explained. To access it, we need to go to the top menu, under Select > Store Selection Area.

A new blank layer titled "selection 1" is created.

The tools on this layer are applied in the same way as the "quick mask". The first visible difference is that the stroke tone on the layer is displayed with a green color instead of a reddish one.

However, we already learned in the "quick mask" section that the color can be modified by clicking on the color box at the top of the layer menu.

Unlike the "quick mask", this layer does not deactivate. In other words, it is a permanent "quick mask". This allows us to collect different shapes that we want to save for future selections and thus speed up the illustration process. If we wish to create more, it is as simple as repeating the process of going to the Select > Store Selection Area button.

 

To select the shape created on the layer, we need to click on the green icon to the right of the selection layer.

Once the shape is selected, it's a matter of going to the desired layer and painting within the selection. If we want the selection layer to stop being visible, we need to hide it by clicking on the eye icon located on the left.

Even if the layer is not visible, we can select the shape drawn on it by clicking on the green icon to its right.

 

This type of mask stands out for allowing us to save as many different selections as we want, and thus be able to use them at any point in the illustration process.

This concludes the tutorial on the different ways to create masks in Clip Studio Paint!