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TOP - Texture Operators

2 min read

TOP - Texture Operators (2D)

TOPs are used for image processing and 2D graphics. They run on the GPU.

Key TOPs

  • Movie File In: Load images or videos.
  • Constant: Create a solid color.
  • Composite: Blend multiple TOPs together (Add, Multiply, Screen, etc.).
  • Blur: Soften textures.
  • Level: Adjust brightness, contrast, and gamma.
  • Render: The bridge between 3D (SOPs/MATs) and 2D (TOPs).

Resolution and Pixel Formats

TOP computations happen under specific settings found on the Common page of almost any TOP node:

  • Resolution: Dictates the width and height. You usually want to dictate this clearly at the start of a chain (e.g., using a Constant TOP set to 1920x1080) and let downstream nodes “Use Input” resolution.
  • Pixel Format (Crucial!):
    • 8-bit fixed: Default for most images/video. Values stay strictly between 0 and 1 (or 0-255).
    • 16-bit / 32-bit float: Critical for Displacement maps, Point Clouds (XYZ coordinates stored as RGB), and Feedback loops. Float formats allow negative numbers and numbers far exceeding 1.0 without being clipped or crushed.

Tips

  • Always check your resolution in the middle-mouse-click menu.
  • Purple = 2D Data.

How to Use TOPs

To use TOPs effectively:

  1. Adding a TOP: Open the OP Create Dialog (Tab) and select the TOP family (purple color).
  2. Generating vs Processing: Start chains with generator TOPs (darker purple, no inputs required) like Movie File In or Constant, then connect them to processing TOPs (lighter purple) like Level, Blur, or Composite.
  3. Connecting: Drag from the output port on the right of one TOP to the input port on the left of another to process the image stream.
  4. Resolution Management: The first node in a chain usually dictates the resolution. Subsequent nodes default to “Use Input” resolution. You can override this in the Common page of any TOP’s parameters.
  5. Viewing Output: Click the ‘Viewer Active’ toggle (bottom right of the node) to interact with the image or background-click ‘Display’ to set it as the network’s backdrop.
  6. Exporting and Converting: You can pass TOP data to other families using conversion nodes like TOP to CHOP to convert pixel color values into channel data streams.

(y-) Next Page: Render TOP

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