Locate the Emission Area from Blender- Game Dev Series 154

S.J. Jason Liu
4 min readMay 9, 2022

Objective: using Blender to locate the specific area to apply the emission effect.

In the previous article, we had highlighted the glass area of testtube model to apply the emission effect. However, if the 3D model with a more complicated UV map, locate the right position would not be so easy. In this situation, we can use 3D modeling software to help us on it.
In this article, I will use Blender to help me find out the UV area and change the Emission base color in Photoshop just like what we did before.

Let’s use this model as an example:

After this article, we will add the emission effect to the center part.

Import to Blender

Blender is a free 3D modeling software which you can easily to use. There are tons of tutorial online you can search how to use it.

Default screen of Blender.

To import the model, we need to locate the position of fbx file.

Confirm the fbx location from folder, and select File> Import> fbx from the drop down menu of Blender.

After imported the model, left click on the default cube and press X> delete.

Notice: If your Blender version is 2.83.20 same as mine, left click would be the default setting of selecting. It would use right click to select if you download the version before 2.8.

Now we have successfully imported the floor model.

UV Editing

To start checking the UV map, select UV Editing layout from the top menu of Blender.

Hold down middle button of mouse to rotate the model.

Left side window is the UV map of our model. Currently you could not see anything on it.
Press Tab to switch into Edit Mode, and now you should see some blocks on UV window.

Then press number 3 key to switch into face selecting mode.
Select the face we want to have emission effect on. If there are multiple faces you need to select, hold shift and select the rest of faces you needed.

And you should see the position you selected was showed on UV map.

Then press A to show all the UV layout.

Now you would know the specific position of where you want to apply the emission effect.
Select UV> Export UV Layout from the drop down menu of UV window.

Now we can edit the Emission effect area from Photoshop.

Back to Photoshop again

Open Photoshop and import the UV Layout we just exported.

Create a new layer and draw 2 white blocks to cover up the position we just checked in Blender.

And make the rest of area to black.

Now export this png and import into Unity as Emission texture.

Let’s check the result!

That’s how to locate the UV spot easily with Blender.

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S.J. Jason Liu

A passionate gamer whose goal is to work in video game development.