Let's Learn Blender! #11: Simple UV Mapping & Image Textures!

Introduction

In this tutorial, we will learn how to add image textures to 3D models in Blender using UV mapping. We will specifically apply a wood texture to a default cube and explore how to export UV maps, paint textures in an online graphics program, and then reapply those textures back in Blender. This guide is perfect for beginners looking to enhance their 3D models with custom textures.

Chapter 1: Adding a Simple Material

To begin, we need to create a material for our cube.

1. Select the Cube

   • Click on the default cube in Blender.

2. Open the Material Properties

   • Go to the Properties Editor on the right.
   • Click on the Material tab.

3. Create a New Material

   • If no material exists, click on "New" to create one.

4. Change Base Color

   • Set any base color (e.g., blue) to see it in the viewport.

5. Switch to Material Preview

   • Change the viewport shading to Material Preview mode for better visibility.

6. Ensure Compatibility

   • This material setup works with both Eevee and Cycles render engines.

Chapter 2: Adding an Image Texture

Next, we will add an image texture to our material using Shader Nodes.

1. Access Shader Nodes

   • Go to the Shading workspace at the top or open the Shader Editor in your layout.

2. Split the Shader Editor

   • Right-click on the top right corner of the Shader Editor and drag to split it into two.

3. Add an Image Texture Node

   • In the Shader Editor, press Shift + A to add a node.
   • Select Texture > Image Texture.
   • Connect the output of the Image Texture node to the Base Color input of the Principled BSDF node.

4. Open the Wood Texture Image

   • Click "Open" in the Image Texture node and select your wood texture image from your desktop.

Chapter 3: UV Maps - Marking Seams and Creating a UV Map

Now we will create a UV map to correctly apply the texture to our cube.

1. Open the UV Editor

   • Split the Shader Editor again and change the top editor type to UV Editor.

2. Enter Edit Mode

   • Select the cube and press Tab to enter Edit Mode.

3. Select All Faces

   • Press A to select all faces.

4. Mark Seams

   • Switch to Edge Select mode.
   • Select edges in a capital U shape on the top and bottom of the cube.
   • Right-click and choose "Mark Seam" or press Ctrl + E and select "Mark Seam".

5. Unwrap the UV Map

   • Ensure all faces are selected and press U, then choose "Unwrap".
   • Your UV map will appear in the UV Editor.

6. Adjust the UV Map

   • Scale (S) or move (G) the UV map as needed to fit within the texture boundaries.

Chapter 4: Exporting a UV Map as PNG

Next, we will export the UV map for painting.

1. Select All in UV Editor

   • Ensure everything in the UV Editor is selected (A).

2. Export the UV Layout

   • Go to UV > Export UV Layout.
   • Save as a PNG file, optionally setting the size to 1024x1024 and fill opacity to 0.

Chapter 5: Painting a Texture Using the UV Map in Photopea

Now we will use Photopea, a free online graphics tool, to paint our texture.

1. Open Photopea

   • Navigate to Photopea.com.

2. Open UV Layout

   • Upload your exported UV layout by going to File > Open.

3. Open Wood Texture

   • Again, go to File > Open and select your wood texture image.

4. Copy UV Layout onto Wood Texture

   • Select the UV layout, copy it, and paste it onto the wood texture.
   • Resize it to fit correctly.

5. Create a New Layer for Painting

   • Create a new layer for your letters.
   • Use the Brush Tool to paint letters (e.g., A, B, C, etc.) on the wood texture.

6. Export the Painted Texture

   • Hide the UV layout layer and go to File > Export As to save your painted texture as a PNG.

Chapter 6: Applying the Painted Texture to the 3D Model

Now we will apply the newly created texture back to the cube in Blender.

1. Return to Blender

   • Minimize Photopea and return to your Blender project.

2. Open the New Texture

   • In the Shader Editor, select the Image Texture node.
   • Click the folder icon and select the newly painted texture from your downloads.

3. Check the Result

   • Ensure the texture appears correctly on all the faces of the cube.

Chapter 7: Packing the Image Textures into the Blend File

To ensure your texture is saved with your Blender file, we will pack it.

1. Save the Blender File

   • Go to File > Save As and save your file on your desktop.

2. Pack External Data

   • Go to File > External Data > Pack All Into .blend.
   • This embeds the texture files within your Blender project.

Conclusion

In this tutorial, we covered the essential steps for UV mapping and applying image textures to 3D models in Blender. We learned how to create materials, mark seams, unwrap UV maps, and paint textures using Photopea. By following these steps, you can enhance your models with custom textures. For the next steps, consider exploring PBR texturing for more realistic effects. Happy Blending!