# SOLARIS — Knowledge MOC > [!abstract] About > Personal **Solaris (Houdini LOP / USD)** knowledge base — what Solaris is, the **node reference**, **scene-graph** essentials, **workflows** (asset / shot / instancing), **department** notes (lighting, lookdev, rendering), **custom LOP HDAs**, troubleshooting and resources. Sits on top of the [[../../../PROTOCOL/USD/USD MOC|USD MOC]] for USD theory. ## 🧭 Reading Order for Newcomers 1. **What is Solaris?** — [[NODES/SOLARIS What is it|SOLARIS — What is it]]. 2. **USD theory** — [[../../../PROTOCOL/USD/Notes/USD KNOWLEDGE/6.30 USD Theory|6.30 USD Theory]] + [[../../../PROTOCOL/USD/Notes/USD KNOWLEDGE/USD terms and definitions|USD Terms & Definitions]]. 3. **Reference vs Sublayer** — [[NODES/SOLARIS Reference VS Sublayer VS Merge|Reference VS Sublayer VS Merge]]. 4. **Asset workflow** — [[../../../ARTFX OSMIUM/PIPELINE/Notes/PIPELINE ASSET|OSMIUM PIPELINE ASSET]]. 5. **Shot workflow** — [[../../../ARTFX OSMIUM/PIPELINE/Notes/PIPELINE SHOT PART 01|SHOT PART 01]] + [[../../../ARTFX OSMIUM/PIPELINE/Notes/PIPELINE SHOT PART 02|SHOT PART 02]]. 6. **Instancing & Cloning** — [[WORKFLOW/SOLARIS Instancing|SOLARIS Instancing]], [[WORKFLOW/SOLARIS Cloning|SOLARIS Cloning]]. 7. **Karma rendering** — [[../KARMA/KARMA MOC|KARMA MOC]]. --- ## 0. Resources - [[NODES/SOLARIS Ressources|SOLARIS Resources]] — external links and references. ## I. Introduction — Solaris & USD in Houdini - [[NODES/SOLARIS What is it|SOLARIS — What is it]] — the LOP context explained. - [[Houdini Solaris is sweet|Houdini Solaris is Sweet]] — short why-Solaris note. - [[HOUDINI Lop Import|HOUDINI LOP Import]] — bring SOP geometry into LOPs. - [[6.125 HOUDINI USD Attribute|HOUDINI USD Attribute]] — attribute mapping SOP ↔ USD. ### USD Theory (from PROTOCOL) - [[../../../PROTOCOL/USD/Notes/USD KNOWLEDGE/6.30 USD Theory|6.30 USD Theory]] — core USD concepts. - [[../../../PROTOCOL/USD/Notes/USD KNOWLEDGE/USD terms and definitions|USD Terms & Definitions]]. - [[../../../PROTOCOL/USD/Notes/USD KNOWLEDGE/USD Extension|USD File Extensions]]. - [[../../../PROTOCOL/USD/Notes/USD KNOWLEDGE/ANIMAL LOGIC use of USD|Animal Logic — USD use]]. ## II. Workflows ### Asset - [[../../../OUT OF PUBLISH/ZBRUSH/SOLARIS ASSET TURNTABLE SCENE|SOLARIS Asset Turntable scene]] *(private legacy)*. - [[../../../ARTFX OSMIUM/PIPELINE/Notes/PIPELINE ASSET|OSMIUM PIPELINE ASSET]] — asset publishing. ### Shot - [[../../../ARTFX OSMIUM/PIPELINE/Notes/PIPELINE SHOT PART 01|OSMIUM SHOT PART 01]] — sequence work. - [[../../../ARTFX OSMIUM/PIPELINE/Notes/PIPELINE SHOT PART 02|OSMIUM SHOT PART 02]] — shot work. - [[WORKFLOW/Advanced USD Writing different point number|Advanced USD Writing — different point counts]]. - [[WORKFLOW/Write USD with moving point number - Pop - FX|Write USD with moving point counts — Pop / FX]]. - [[WORKFLOW/SOLARIS Instancing|SOLARIS Instancing]]. - [[WORKFLOW/SOLARIS Cloning|SOLARIS Cloning]]. - [[WORKFLOW/SOLARIS TOP Render Fetch|SOLARIS TOP Render Fetch]] — TOP integration. ## III. Departments ### 💡 Lighting - [[DEPARTMENT/SOLARIS Lighting|SOLARIS Lighting]]. ### 🎨 Lookdev - [[LOOKDEV HOUDINI SOLARIS|LOOKDEV HOUDINI SOLARIS]] — Solaris-side lookdev. - [[NOTES/HOUDINI Solaris custom AOV from shading|Custom AOV from shading]]. - See full [[../KARMA/KARMA MOC|KARMA MOC]] for shader / render specifics. ### 🎞️ Rendering - [[NODES/Solaris Rendering TIps|Solaris Rendering Tips]]. - [[NOTES/HOUDINI Solaris custom AOV from shading|Custom AOV from shading]]. - [[../KARMA/KARMA MOC|KARMA MOC]]. ## IV. Core Nodes ### A. Stage Import / Management - [[NODES/SOLARIS Reference VS Sublayer VS Merge|Reference VS Sublayer VS Merge]]. - [[NODES/SOLARIS Reference VS Sublayer|Reference VS Sublayer]] — shorter variant. - [[NODES/Houdini Payload|Houdini Payload]]. - [[NODES/SOLARIS Sceneimport|SOLARIS Sceneimport]]. ### B. Prim Creation & Modification - [[NODES/SOLARIS Scope|SOLARIS Scope]]. - [[NODES/SOLARIS Primitive Node|SOLARIS Primitive Node]]. - [[NODES/SOLARIS Stage Manager|SOLARIS Stage Manager]]. - [[NODES/SOLARIS Layerbreak|SOLARIS Layerbreak]]. - [[NODES/SOLARIS SOP Modify|SOLARIS SOP Modify]]. - [[NODES/SOLARIS Component builder - Explore Variants|Component Builder — Explore Variants]]. - [[NODES/SOLARIS Configure Layer|SOLARIS Configure Layer]]. - [[NODES/SOLARIS Geometry settings|SOLARIS Geometry Settings]]. - [[NODES/SOLARIS Mesh Edit|SOLARIS Mesh Edit]]. - [[NODES/SOLARIS Camera|SOLARIS Camera]]. - *Primitive Create / Edit Properties / Visibility / Delete Prim* — *WIP*. ### C. Assembly & Instancing - [[WORKFLOW/SOLARIS Instancing|SOLARIS Instancing]] — Assembly, Instance, Point Instancer. ### D. Material Assignment - *Material Library / Material Bind* — *WIP*. ### E. Lighting & Rendering Nodes - *Distant Light, Dome Light, Environment Light, Render Settings, Karma Render ROP* — *WIP*. - [[NODES/Solaris Rendering TIps|Solaris Rendering Tips]]. ### F. Layout - *Merge, Prune, Filter, Sort* — *WIP*. ## V. Scene Graph - [[SCENE GRAPH/SOLARIS Scene graph details|Scene Graph — details]]. - [[SCENE GRAPH/SOLARIS PrimType|PrimType]]. - [[SCENE GRAPH/SOLARIS GEOMsubset|GEOMsubset]]. ## VI. Custom HDAs (LOP) - [[HDA/HOUDINI HDA SceneInspector|HDA — Scene Inspector]] — extracts a static scene snapshot for AI debugging. - [[HDA/HOUDINI HDA PythonPrinter|HDA — Python Printer]] — logs everything you do in the input node. ## VII. Troubleshooting - [[TROUBLESHOOTING/SOLARIS General Optimisation|General Optimisation]]. - [[TROUBLESHOOTING/SOLARIS Fix and problems|Fix and Problems (from students)]]. --- ## 🔗 Related - [[../HOUDINI MOC|HOUDINI MOC]] — parent index. - [[../KARMA/KARMA MOC|KARMA MOC]] — render side. - [[../../../PROTOCOL/USD/USD MOC|USD MOC]] — USD theory. - [[../../KNOWLEDGE MOC|KNOWLEDGE MOC]]. - [[../../../ARTFX OSMIUM/PIPELINE/PIPELINE MOC|OSMIUM PIPELINE MOC]] — the production pipeline using Solaris.