Physically Based Rendering Tutorial

Physically Based Rendering (PBR) is a type of render solution that simulates how materials react to realistic light behavior. For example, certain metallic properties will cast reflections or change the way light bends and refracts through different types of glass.

In this guide, you will learn some of the basic workflows when designing PBR textures in Minecraft: Bedrock Edition and create a custom texture set for the emerald ore block.

We're going to use emerald ore for this tutorial. When we're done with it, the stone part will look rougher and the emerald chunks will look more metallic in the light, and glow faintly in the dark.

By the end of this guide, you will learn:

• How to create a custom Texture Set using Adobe Photoshop.
• How to utilize color channels to assign multiple maps in a single file.

Requirements

You will need to complete the following tutorials:

• Introduction to Resource Packs
• Introduction to Physically Based Rendering

While textures will be provided, you will need to have digital painting software to create your textures. This tutorial will be using Adobe Photoshop.

Set up the Texture_Set.JSON file

First, you will need to create a Texture Set .JSON file that will load your new textures into the game.

Note

This tutorial is a continuation of the Introduction to Physically Based Rendering and will assume that all setup steps have been completed as mentioned in the previous guide.

1. In your behavior pack, navigate to the textures/blocks folder.
2. Create a file called emerald_ore.texture_set.json and add the following code to it.

emerald_ore.texture_set.json

{
  "format_version": "1.16.100",
  "minecraft:texture_set": {
    "color": "emerald_ore",
    "metalness_emissive_roughness": "emerald_ore_mer"
  }
}

5. Save and close the file.

Create the Textures

With the JSON file set up, let's take a look at how to set up Adobe Photoshop for working with Minecraft Textures. For your "color" value, we will be using the existing vanilla texture that is included in the Vanilla Resource Pack.

1. Right-click on the image above and download it.
2. Right-click on the file, select Open with, and select Adobe Photoshop.
3. When Photoshop opens, select File... Save As... and save the file as a .PSD file type.

Create the 'mer' texture

In the previous guide, when you set up the Texture Set JSON for the emerald ore block, you may have noticed that there is a file called emerald_ore_mer that is set as the "metalness_emissive_roughness" value. mer in this case is an abbreviation for metalness_emissive_roughness because it's a single texture file that contains all three maps.

emerald_ore_mer.png Overview

Because each texture map functions as a grayscale value, each map can be assigned a color channel:

• Red channel: Metallic map. Value set in a range of 0.0 to 1.0.
• Green channel: Emissive map. Value set in a range of 0.0 to 1.0.
• Blue channel: Roughness map. Value set in a range of 0.0 to 1.0.

Roughness

Because emerald ore is depicted as pieces of emeralds embedded in gray stone, it's perfect for showing how we can use the Roughness Map to make the emerald portions look smoother and the stone look rougher.

1. Create a new layer group by selecting the folder icon at the bottom of the Layers tab.
2. Name the layer group Roughness.
3. In Photoshop, create a new layer and name it Rough Map.
4. Paint over the portions of the block with emeralds in black to make them smooth.
5. Paint over the stone with white to make the stones rough.
6. Right-click the Roughness layer group and select Blending Options.
7. Under Advanced Blending, un-check the Red and Green channels so that Blue is the only one with a checkbox.
8. Select OK to close the Blending Options window.

Here is the output of the painting. It shows as blue and black since we turned off the red and green channels.

With the maps being grouped in a single layer group called Roughness, you can combine multiple layers to paint multiple values without having to worry about any overlapping or interrupting work.

Emissive

While the emerald ore block does not natively emit any light, we are going to add a low level of glow to the emeralds to showcase emission.

1. Create a new layer group by selecting the folder icon at the bottom of the Layers tab.
2. Name the layer group Emissive.
3. In Photoshop, create a new layer and name it Emissive Map.
4. Paint over the portions of the block with emeralds with white to make them emit light.
5. Paint over the stone with black.
6. Right-click the Emissive layer group and select Blending Options.
7. Under Advanced Blending, un-check the Red and Blue channels so that Green is the only one with a checkbox.
8. Select OK to close the Blending Options window.

Here is the output of the emissiveness layer only.

Metallic

Finally, we will make the emerald chunks look more metallic.

1. Create a new layer group by selecting the folder icon at the bottom of the Layers tab.
2. Name the layer group Metallic.
3. In Photoshop, create a new layer and name it Metallic Map.
4. Paint over the portions of the block with emeralds with white.
5. Paint over the stone with black.
6. Right-click the Metallic layer group and select Blending Options.
7. Under Advanced Blending, un-check the Red and Blue channels so that Green is the only one with a checkbox.
8. Select OK to close the Blending Options window.

Here is the output of the metallic layer only.

Export the File

With all three texture maps set up and assigned correctly, you can now export the file.

1. Select File...Save As... and save the file as emerald_ore_mer.png.

Or, you can download the file below.

2. Place the mer file in the textures/blocks folder along with the Texture Set JSON file and the block texture.

What's Next?

Fog in Resources

Now that you have learned how to create your custom physically based rendering texture packs, you can take a look at how fog has been adjusted in the Render Dragon engine and customize the settings to your liking.

Fog in Resource Packs