PBR Game Guru Max – Easy workflow how to
PBR workflow for Game Guru Max
Physically based rendering or (PBR) for short is a texture that is created to mimic the way light interacts with surfaces in the real world. It is important for game development because it helps create more realistic textures and shows finer detail on lower poly models.
There are two types of PBR workflows, Roughness and Specular, but today we will focus on the roughness. A roughness PBR workflow is a texture set that consists of 4 texture maps. Albedo or more commonly known as color/diffuse a metalness map, roughness map and AO map or (Ambient Occlusion). These maps combined on a model are what give the model more deal than it may necessarily have, being lower poly.
Surface maps, like we use in Game Guru Max and other game engines, work like a full set of PBR materials. It does this by something called channel packing. Channel packing takes the RGB (Red, Green and Blue) channels of an image and uses them to show the roughness, metalness and AO of a texture. Game Guru Max then interprets this texture to display the correct PBR output.
How do we channel pack?
There are a number of ways paid and free, let’s take a look. The first is a program created by one of the community Graphix, Graphix has created a number of useful programs for sale on the game creator store (TGC) but for this we will be looking at xPack – Texture Packer. This program lets you combine the metalness, roughness and AO into a single image
For this to work, however, you need to pack them in the correct order.
RED = Ao
Green = Roughness
Blue = Metallic
By packing these images in this order, Game Guru Max can interpret the image correctly and apply the PBR.
What happens if I don’t pack it in the right order?
If you pack them out of sequence, Game Guru Max will not be able to interpret the texture correctly, and you will not achieve the desired result.
The second program is a free program called Materialize by Boundingbox. The benefit of this program is that you can take a single texture image and create all the maps that you need. For a full tutorial on how that works, you can watch the YouTube video below.
Once you have created all of your maps, on the right and side you can see a button to save a” proprietry map” and three areas to place your RGB map. Select the maps you want for your surface map and save the file.
That is it. You now have your surface map and are ready to proceed
What is next?
Check out the video above to see the basics in blender
Now that we have our PBR maps, what do we do with them? For this example, we are going to start with a Blender. Let’s say we have our model ready, and we want to apply our texture. We head over to the shading tab and select our material. First off, we add our colour texture by hitting control A and selecting texture map.
Navigate to where you have saved your texture and then link that node in to your base colour. From here, you can duplicate your node by selecting the colour node and press shift D twice to make two duplicates of your node. In one load your surface map and in the other load your normal map.
Next on these two nodes change the drop-down to non-colour data, then link the nodes to the correct location. The Surface map can be linked to the roughness and the metallic inputs, and the normal map can be linked to the normal map input. For more control, hit shift A and add a normal map node to give you more control. Now display materials in your view port and that is it! You have your PBR material setup in blender.
Final Step!
Now that we have achieved this, let us import our PBR texture in the Game Guru Max and apply this texture.
First off, when importing a model in to Game Guru Max if you have your .fbx and texture set in the same folder it makes importing so much easier.
In Game Guru Max head over to add an object and then down in the middle click on import new object. From there, navigate to your .fbx and click import. You should see your model in the view port with the textures applied. If not, you can easily add them by selecting material from the menu on the right and navigating to the correct map. Once these have all been added, import them in to your library and that is it! You are good to go. Your new PBR asset has successfully been imported in to Game Guru Max and is ready for your game.
Find PBR examples here