Quick and Easy: Alter Your Pre-Built Unity Texture Maps using Krita.
Objective: show the Reader how to alter the texture map of a Unity game object’s material using Krita.
I’ve been working my way through the GameDevHQ’s Guide to Beautiful Games in Unity course, and have finally arrived at the point where I’m looking at my work and think to myself that the colors simply don’t look right. To set the scene, I’m in a Sci-Fi futuristic laboratory, and instead of a dull, clinical metallic gray appearance to my surfaces, I have this happy Halloween orange color. Looks too cheerful for my taste.
So how would I change this?
You need to alter the material associated with the game object, or more precisely, the texture map. You can find the texture map by selecting the game object and looking at the Mesh Renderer component in the Inspector. In this component, you will find the Material used.
In the example below, I have selected a floor tile called Scifi_Floors_05 (9), and when I look at the Mesh Renderer, I see the material Scifi_Floor_01_12.
Looking in my Project folders, I find the Scifi_Floors_01_12, and dig into its sub-folders to locate the Materials and the tex (textures) folders.
Select the Scifi_Floors_01_12 material in the Project folder to open up its parameters in the Inspector window. Under the Surface Inputs, we see three maps of interest: the Base, Metallic, and Normal maps. The objective here is to alter the Base Map to a more suitable pallet for the Scene I’m developing.
When you look at the little square icon to the left of Base Map, you can see a png file called Grounds_AlbedoTransparency in the textures folder of the Project window. This is what we need to alter. The next step will be to locate this file on your hard drive. To do this, right-click on the png file and select Reveal in Finder (for a Mac) of Find in Explorer (for Windows). This will bring up a window showing exactly where the png in question lives. We are now ready to import into Krita.
Now the course I’m following went through these steps using Adobe Photoshop, and suggested you could do the same with GIMP. Being rather unfamiliar with those particular software programs, I set out to find an alternative.
I opted to use Krita, which is a professional free and open source painting program.
Start Krita, and with the finder window open, simply select and drag the Grounds_AlbedoTransparency.png into the Krita new project window as per the example below. This will open the texture map onto a layer and you're now ready to start making modifications.
Now I’m by no means super comfortable with Krita, so I apologize in advance if my methods are not the most efficient. At this point, you want to duplicate your visible layer to avoid tampering with the original png file. I do this by right-clicking on the layer called Background and selecting Duplicate Layer or Mask. Now you may ask yourself if this is really necessary, and I suppose you are correct to some extent since as long as you are careful to rename the file when comes time to save it, the original should remain intact. I guess duplicating at this stage simply saves you the trouble of having to reimport it if you mess it up completely. So, you’re basically keeping an original copy and messing with something you can simply trash if your creativity gets the best of you :)
Now that you have turned off the Background (click on the eyeball), leave the Copy of Background layer visible and select Filter > Adjust > HSV Adjustment…
Play with the Hue / Saturation / Lightness until your layer colors are changed to a more grayish appearance. Press OK to set your changes.
You can further fine-tune by selecting Filter > Adjust > Levels… and adjust the Input and Output levels as desired. Once again, press OK to set your changes.
Once you’re happy, select File > Save As… Ensure you are saving back into the source directory (it should automatically select the folder from where you clicked and dragged the original png into Krita), and that the file type is set to PNG image. Give it a new name to differentiate from the original file and press Save.
You will see that the modified png file is now in your original directory.
Now to apply this new texture to your game objects, select the Materials Scifi_Floors_01_12 in the Inspector. Then you click and drag your new Grounds_AlbedoTransparency_MetalGrey texture from the tex folder onto the little square icon to the left of your Base Map.
So there you have it. Changing the texture can be done relatively easily and can drastically change the mood in your Scene. I hope this demonstration using Krita was useful. As always, thanks for reading :)