Hierarchical LOD - Semi Automatic
Open World Settings tab Window / World Settings.
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Enable Hierarchical LODSystem. Window / Hierarchical LODSystem / Enabled Hierarchical LOD System.
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Open Hierarchical LOD Outliner Window . Window / Hierarchical LOD Outliner.
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Add Levels.
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Create clusters by dragging static meshes from scene outliner into HLOD Outliner.
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(Optional) Select LODActor in LODLevel(N-1) and drag them to LODLevel(N).You can build clusters by dragging LODActors(clusters) from previous level into a next level.
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(Optional) You can place HLOD Volumes in your level. Select static meshes in level.
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Surround the selected actors in a volume.
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(Optional) Check Only Generate Clusters for Volumes in cluster settings to only use volumes for cluster generation.
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(Optional). You can tag objects to be excluded from HLOD by selecting the actor. Go to Details / HLOD and un-check Include Component for HLOD Mesh Generation.
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(Optional) Check Allow Specific Exclusion in cluster settings.
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Setup transition screen size. (Optional) override draw distance.
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Enable Simplygon Proxy Mesh Generation
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Generate Proxy Meshes for Cluster
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