This tutorial explains how to create a Customizable Object with a feature that allows for changing and choosing a character's skin tone. Once the tutorial's steps are followed and compiled, a selector slider, with a color skin bar on top, is to be displayed and the user will be able to select a skin tone through it and to see immediately the variation applied to the character.
= Change the skin tone of a character
(NOTE) The resulting Customizable Object of this example can be found in the [[ https://work.anticto.com/w/mutable/unreal-engine-4/examples/#village-demo | Village Demo ]] in //Content/Examples/HowTo// named "SkinTone"
== Assets required
* One material asset or material instance with one color parameter (it may or may not have textures but only one slot converted to parameter)
* One skeletal mesh with only one material slot
* One texture asset of the base skin texture of the character
* One mask texture of the character's skin
* One texture asset of a "skin color bar"
(NOTE) The assets used in this example can be found in the [[ https://work.anticto.com/w/mutable/unreal-engine-4/examples/#village-demo | Village Demo ]] in //Content/HowTo/SkinTone//
1) The first step is to create a [[ URL | Customizable Object]] asset. Open it and name the [[ https://work.anticto.com/w/mutable/unreal-engine-4/user-documentation/nodes/base-object/ | Base Object ]] node in the [[ URL | Graph Node Properties ]] and set a [[ URL | Reference Skeletal Mesh ]] in the [[ URL | Object Properties ]] tab.
> In this example, the Customizable Object asset is named "Skin Tone", the **Reference Skeletal** is "SkinTone_BaseBody", the **Material** is called “SkinTone_M” and the **Skeletal Mesh** is the same as the Reference Skeletal’s one.
2) As the objective is to change the skin tone of the character, a node that can modify the texture parameters of the skeletal mesh's material and apply a "color bar" instead of a simple texture is needed. A **Texture Layer** node allows modifying a base texture with blending options and masks. From the "Base Color" connection in the **Material** node, create a [[ https://work.anticto.com/w/mutable/unreal-engine-4/user-documentation/nodes/texture-layer/ |Texture Layer ]] node.
3) With the **Texture Layer** node selected, in the Graph Node Properties tab, click the "+" button in the Layers sub-tab. This creates a layer that results in two new slots in the **Texture Layer** node.
> Each layer created in the **Texture Layer** node has two connections: the "Layer X" and the "Mask X" connections.
Still in the **Graph Node Properties**, click to unfold the tab of the new layer created. Choose the effect of blending among all the options displayed unfolding the Effect sub-tab. This effect will determine the visual interaction between the texture to be added to create the skin tones and the base layer.
> The Effect in this example is left by default as "Cotle Softlight".
4) Create a **Texture** node dragging and dropping from the "Base" connection of the **Texture Layer** node.
5) With the new **Texture** node selected, choose a base texture for the character in the Graph Node Properties tab. This texture is the one on which the blending effect will be applied.
> In this example, the "SkinTone_BaseTexture_D" texture is used.
6) Create another **Texture** node from the "Mask 0" connection of the **Texture Layer**. This texture is the mask related to the skin color of the character.
7) In the Graph Node Properties, choose a black-and-white texture which masks in black the non-skin parts of the base texture, for example, the eyes, and leaves the rest in white.
> In this example, for the "Mask 0" connection, the "SkinTone_SkinMask" texture is used.
8) In the "Layer 0" connection, a texture with color information is to be connected. This texture should be a selected color of a "skin color bar" used mixed with the "Base" texture through the blending effect already selected. To start with, a node that takes samples from a color bar is the needed one. Create a [[ https://work.anticto.com/w/mutable/unreal-engine-4/user-documentation/nodes/sample-texture/ | Sample Texture ]] node. Link its "Color" connection to the "Layer 0" one of the **Texture Layer** node.
9) Create a **Texture** node from the "Texture" connection of the **Sample Texture** node. This texture should be the image from which the **Sample Texture** node takes each selected color.
10) In the Graph Node Properties, and with this last **Texture** node selected, set the required "skin color bar".
> In this example, the" SkinTone_ColorBar" texture is used.
11) Now, the only remaining node is the one that allows selecting a color value and creating a slider. Click and drag from the "X" connection of the **Sample Texture** node to create a **Float Parameter** node. This node allows picking a horizontally-based value from the color bar texture.
12) Select the **Float Parameter** node and name it in the Graph Node Properties tab. This name is appearing as a title next to the "skin color bar" when compiling.
Change the Default Value if preferred. It is to provide the color value chosen as the default one after compiling the first time.
>In the example, the Parameter Name used is "Skin Tone" and the Default Value is changed to "0.0" to display the first color of the "skin color bar" as default.
Click the "+" icon of the Description Image to enable the option of showing an image in the slider selector. Name this new connection by clicking on the small sub-tab of this new "0" layer created and changing the default name.
>In this example, the Description Image is called "Skin Color Bar".
13) Back to the **Source Graph**, connect the "Skin Color Bar" connection of the** Float Parameter** node to the "Image" one of the **Texture** node.
14) Before compiling, check that the **Source Graph** looks similar to the example below:
15) Compile. The result in the Preview Instance Properties tab should look similar to the image below.
Try to move the "selector slider" and select a color. It must immediately be visible on the character's skin.
(WARNING) If the colors displayed on the character skin don't look similar to the ones of the "skin color bar", try to change the blending effect in the **Texture Layer** node.