.HIP

Introduction

HIP is the scene file of Houdini, SideFX’s procedural 3D program, known for simulations of smoke, fire, water and destruction in visual effects. A Houdini scene is a network of nodes, each an operation whose result feeds the next, and the HIP file stores those networks with every node’s parameters, expressions and scripts.

The extension shows which licence saved the file: .hip for the commercial editions, .hiplc for Houdini Indie and .hipnc for the free non-commercial Apprentice edition. Commercial Houdini opens the other kinds but treats the session as limited or non-commercial.

Structure

Because a Houdini scene is mostly a recipe, a HIP file is usually small: it stores the nodes and their settings, not the geometry they make, which Houdini rebuilds when the scene is cooked. Geometry that is slow to rebuild is written to separate cache files, such as Houdini’s own .bgeo.

SideFX does not document the file as a format. Houdini ships with command line tools that can expand a HIP file into a folder of text files, one set per node, and collapse it back.

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