How to Use Window Texture Coordinates in Blender

The Window output on the Texture Coordinate node in Blender maps textures directly to the 2D dimensions of your render window or viewport screen. Instead of wrapping around a 3D object’s surfaces, textures using Window coordinates remain fixed relative to the camera view, making them ideal for screen-space effects, camera overlays, parallax illusions, and stylized shading. This guide explains how to locate, set up, and control the Window texture coordinate in Blender's Shader Editor.

How to Set Up the Window Texture Coordinate

Using the Window coordinate requires just a few basic nodes in the Shader Editor:

  1. Open the Shader Editor: Select the 3D object you want to apply the material to, then open the Shader Editor workspace.
  2. Add a Texture Coordinate Node: Press Shift + A, navigate to Input > Texture Coordinate, and place the node in the workspace.
  3. Add a Texture Node: Press Shift + A and add your desired texture, such as an Image Texture, Noise Texture, or Voronoi Texture.
  4. Connect the Nodes: Drag a line from the Window output socket of the Texture Coordinate node into the Vector input socket of your texture node.
  5. Connect to the Material Output: Connect the Color or Factor output of your texture node into your shader (such as the Principled BSDF) and view the result in Material Preview or Rendered mode.

When you rotate or move the camera, the object moves, but the texture stays pinned to the screen viewport.

Key Characteristics of Window Coordinates

  • Screen Space Values: The X and Y coordinates range from 0.0 to 1.0, starting from the bottom-left corner of the camera viewport to the top-right corner.
  • Aspect Ratio Scaling: By default, Window coordinates conform to the aspect ratio of your render resolution. If your render aspect ratio is not square (e.g., 16:9), the projected texture may appear stretched.
  • Resolution Independence: The texture maps across the current view regardless of how close or far the object is from the camera.

Fixing Aspect Ratio Distortion

If your texture appears stretched across the screen, you can correct the scaling using a Mapping node or Vector Math node:

  1. Add a Mapping node (Shift + A > Vector > Mapping) and place it between the Texture Coordinate node and your Texture node.
  2. Adjust the Scale values on the X or Y axis depending on your render aspect ratio. For a standard 16:9 ratio, set the X scale to 1.777 (16 divided by 9) or adjust the Y scale to compensate.

Common Use Cases

  • Interior Parallax Illusions (Fake 3D Windows): Combine Window coordinates with mapping math to create the illusion of a 3D room inside a flat plane, often used in architectural visualization for buildings.
  • Stylized Screen-Space Shading: Apply halftone patterns, cross-hatching, or screen-space film grain that remains static as objects move through the frame.
  • Camera Overlays and Vignettes: Map UI graphics, camera viewfinders, or screen-edge shadows directly onto lenses or glass materials.