LiveMesh

This page is generated from docs/BLENDER_LIVE.md. To change it, edit that file in the repository: edits made here are replaced.

LiveMesh

LiveMesh sends rigged mesh edits to your own animated avatar and static mesh edits to local world objects or attachments in Block Viewer. You can sculpt, move vertices, paint weights, edit UVs, adjust shape keys and geometry modifiers, and see the result without saving or uploading. The preview is local: other residents do not see it, and it does not create inventory items or charge an upload fee.

Static objects (plug-in 0.13.0)

LiveMesh accepts rigged and non-rigged mesh selections, including a mixture in the same synchronization list. Connect with the selection or use Add selected meshes. A static mesh needs neither an armature nor vertex weights; shape keys, geometry modifiers, UVs and live materials still work. Geometry is expressed in metres, retaining authored rotation/scale and ignoring the object's Blender scene translation; linked children retain their offsets from the root. An existing rig without valid weights remains an error rather than silently turning into a static object.

With plug-in 0.14.0+, adding several static meshes at once creates one linkset, even when they have no Blender parents. The active selected static mesh becomes the root; if the active object is rigged, the first static entry is used. Each mesh keeps its own geometry, materials, relative position, rotation and size. Rigged meshes stay outside these static linksets.

With plug-in 0.14.1+, click a name in Blender's synchronization list to select it. Ctrl-click (Cmd-click on macOS) adds or removes individual entries; Shift-click selects a range in the displayed order. Group groups only the selected static entries, using the active selected entry as root. Ungroup on a selected root makes its entire linkset independent. On selected children, it detaches only those children and keeps the other members linked. Select any member and click Make root to change the root of its complete linkset. These operations do not change Blender parents or object transforms. Removing a root from the list promotes a remaining member. Groups survive save/load, renaming, list reordering and Undo/Redo.

Existing entries without an explicit group still follow Blender parenting: the highest synchronized static mesh parent is the root, including through intermediate empties. Explicit grouping overrides this hierarchy; Ungroup also keeps parented meshes independent in the viewer. The source list groups the prims under one root, numbered #1, #2 and onward, with an object/prim counter matching the build tools. Clicking Edit uses the whole linkset by default. Enable Edit linked parts in the normal build tools or object context menu to select a child alone. All static draw prims, including extra material batches, are direct children of the same root rather than nested objects. Rez, drop, derez, body/HUD attachment and detach apply to the complete set, even when requested from a child. Unparenting inherited groups or using Ungroup creates independent previews and preserves their current placement. Paused or absent roots are not referenced. Linksets require the viewer's object-links capability.

Static objects initially appear on the floor two metres in front of your avatar. Select the source in Block's LiveMesh window to Edit, Drop to ground, Derez, Attach to a body point or Attach to HUD. Detach removes a worn preview; Rez brings it back. Derez/detach keep the source in the list and subsequent Blender edits never rez it automatically. The visible checkbox remains independent. Stop clears all session previews and placement.

Edit uses the normal Block Viewer translation, rotation and size tools, with the same controls for body attachments and HUDs. Right-clicking any prim opens the ordinary object context menu, with Edit, Edit linked parts, Inspect and supported local attachment/removal actions. Inspect shows one object with its separate root and linked prims. Link/unlink authoring remains in Blender's synchronization list. Numeric position, rotation and size are also available below the source list; attachment positions use the attachment point's local frame. Dropping a body attachment retains its current orientation and horizontal location, resting its rotated bounds on the supporting floor or terrain below it. Elevated platforms and skybox floors are picked from scene geometry. Dropping a HUD places it in front of the avatar.

Placement survives renaming, source reordering and live geometry/material updates. Size edits act as a multiplier over subsequent Blender dimensions. Render batches for extra materials stay part of one local source. Import/LOD preparation also accepts static sources, through the existing explicit importer. The optional static-meshes handshake feature protects older viewers: update Block Viewer if the plug-in reports it cannot preview non-rigged meshes.

These objects remain local previews visible only in your viewer. They are not uploaded, saved in grid inventory or simulated by the server; no physics or script is started. Rigged sources continue to follow the avatar as before.

Install and connect

1. In Block Viewer, open Build → LiveMesh. In the Plugins tab, click Install in Blender… and select Blender's executable (blender.exe on Windows). The viewer checks only this executable, installs and enables the matching bundled plug-in, and shows the current step followed by a completion message with the Blender version. To list all installations instead, click Search for Blender. It shows each executable's version, path and installed Block LiveMesh plug-in version. Click Install, Update or Enable on the desired row. The viewer chooses the compatible bundled package, installs it and saves its enabled state in that Blender profile.

2. If Blender is already open, restart it when convenient to load the updated plug-in. The viewer never closes its windows or changes your scene. Search for Blender rescans installations. Install in Blender… also supports custom or portable locations and remembers the selected executable for later searches. It never searches or launches other Blender executables. Standard application folders, common portable folders, PATH and Windows application registrations are searched without recursively scanning your disks. Removable drives are added through Install in Blender…, avoiding empty card readers during detection. Prior LiveMesh package files and userpref.blend are preserved under the selected profile's block-backups directory; failed installation restores these files. Newer plug-in versions are never downgraded. Multiple executables of the same Blender major/minor version can share one profile.

   For installation on another computer or manual control, expand Manual installation (ZIP) and click Save Blender plug-in…. The viewer bundles both matching formats; no source checkout, download or external Python installation is needed. Install the ZIP matching your Blender version:

   • Blender 4.2 or later: choose the extension package in the viewer. In Blender, open Preferences → Get Extensions → the top-right menu → Install from Disk, choose that ZIP, and enable it. Allow its network permission: it communicates with 127.0.0.1 only.
   • Blender 2.93–4.1: choose the classic add-on package in the viewer. In Blender, open Preferences → Add-ons → Install, select the ZIP, then enable 3D View: Block LiveMesh. Keep the ZIP intact.

3. In Block's LiveMesh window, open the Connection tab and click Enable preview. The default port is 17655. Change it in both applications if another program is already using that port, or to preview in another viewer.

4. In Blender, open the 3D view sidebar (N) → Block → Live, then Connect to Block Viewer. No object selection or rigged mesh is required. To preview meshes, select them and click Add selected meshes at any time.

5. Edit your mesh. Automatic updates is enabled by default, with an Interval (seconds) of 2. Larger meshes can take longer to capture and prepare. The viewer supplies the animation and avatar shape, independently of Blender's current pose.

Automatic captures wait for a short 150 ms pause during mesh editing, sculpting or painting, so a continuous editing gesture is not interrupted by capture. The chosen interval remains the minimum delay between captures. Update now still captures immediately, and animation playback does not wait for this pause. With a current viewer, geometry and the strongest four skin weights are prepared in bulk as detached byte buffers; the socket worker encodes these directly. Meshes without shape keys or enabled modifiers other than Armature are read directly in their rest state, avoiding a temporary object and a scene evaluation. Other meshes retain the evaluated export path. Material-only changes reuse the captured geometry. Geometry edits still rebuild the mesh at each retained update; all changes currently send a complete snapshot, with compression on the socket worker. Idle connection feedback redraws only the sidebar when its content changes.

If an object cannot be exported or sent, its list row shows a warning button. Click it to open the full error and object name, then Copy error to copy all details to the clipboard. Object errors do not fill the top of the sidebar. The other valid objects continue to update. Fix the reported problem and use Update now, or wait for the next automatic capture, to retry. The entry stays in Blender's list; failed sources are omitted from that preview snapshot. Import and LOD preparation still require the complete requested source to be valid.

The four navigation buttons keep the sidebar focused on one task:

• Live: connection, automatic/manual update controls and the synchronized-object list. Connection settings is collapsed by default and holds the port and coordinates.
• Skeleton: bone visibility and display options. Expand Create an SL avatar to create a starter rig and optional test T-shirt.
• Controls: hand/foot IK, root/COG controls and independent classic/Bento eye targets.
• Weights: separate sections for automatic weights, donor transfer and cleanup.

The Avatar rig selector is shared by Skeleton, Controls and Weights. Navigation belongs to the window manager, stays outside the scene's mesh/settings data, and defaults to Live on a fresh session.

New starter rigs face Blender -Y, like Avastar, with the arms along X. Coordinates → Automatic (Avastar / SL) is the default. It detects each armature's rest orientation and converts its mesh, normals and joint binds to Second Life's +X axes together. Imported compatible Avastar rigs do not need Block-specific bone properties. Older +X LiveMesh rigs and -Y rigs can share one live list without rotating the Blender objects or editing their weights. The explicit SL / Z up and Blender -Y forward choices remain available and retain their saved values. If an older scene explicitly selected native coordinates for an Avastar rig, choose Automatic (Avastar / SL) and click Update now. Existing scenes and skeletons are never rotated automatically. See Avastar's coordinate conventions.

Some rigs, body dev kits in particular, bind their meshes in a rest pose other than SL's T-pose (arms lowered into an A-pose) and on a shape that scales some bones. Each bone keeps that bind pose in its bind_mat property, with or without Avastar installed ("no add-on" kits included). LiveMesh and Import / LOD undo its rotation and scale the way Blender's and Avastar's Collada exports do, so meshes rigged to the kit sit where they do after a normal upload. A bone without its own bind data follows its parent's rotation. An Avastar rig with Use Bind Pose and no bind data at all is undone from each bone's default rest pose, as Avastar's export does. If the rest pose was edited after binding, the stale bind data is ignored and the bones' rest positions are used as they are.

Automatic updates sends changed geometry, weights, UVs, materials and list membership at most once per configured interval (0.1–3,600 seconds). Idle scenes send no repeated snapshots, including unchanged texture-paint content. The interval is expressed in seconds independently of Blender's frame rate. Uncheck this option to work in manual mode: edits remain pending until you click Update now. This button captures immediately while connected, bypassing the interval and resending even unchanged content. During the connection handshake, its request waits until the viewer is ready. Connecting always sends an initial preview, including in manual mode. The interval and automatic/manual choice are saved per scene in the .blend file.

The Synchronized objects list is saved with each scene in the .blend file. Add selected meshes appends mesh objects without duplicates, keeping existing entries and their enabled/paused state. You can prepare the list before connecting. If it is empty, Connect to Block Viewer adds the current mesh selection for convenience; an existing list is used independently of the current selection.

Each row has a selectable name, a synchronization chain toggle and a remove button. Selected names are highlighted; the counter below the list shows the selection size. Turning synchronization off removes the object from the viewer preview while retaining its list entry. Turning it back on sends its latest geometry, weights and materials. Clicking a name only selects entries for the list actions; it does not change the preview or the scene's 3D selection. Paused entries can also be selected and grouped. The remove button removes the entry and its preview, preserving the Blender object. Disabling or removing every entry sends an empty preview. Add/remove and grouping support Undo/Redo. Renaming updates the displayed name and keeps the same object reference. Deleted objects are pruned at the next live tick or list operation.

Disconnecting retains the list and pause flags. Loading another file stops the connection and restores that file's saved list. During a connection, switching scenes schedules the new scene's enabled entries according to its update settings. Update now also retries the current enabled objects after an error. List changes respect the update mode and interval; in manual mode, click Update now to publish additions, pauses, resumptions, removals or grouping changes.

The add-on reconnects automatically when the viewer becomes available again, resending its latest snapshot. Disconnecting Blender leaves the last good preview visible. Block's Stop and remove closes the listener and removes the preview; Remove meshes withdraws all current objects until restored. Closing the window keeps the bridge active. The listener is off on each viewer launch, and changing accounts stops it.

Manage objects and upload in Block Viewer

Block's Build → LiveMesh lists each source object by its Blender name, even if it spans several render batches. The window separates Connection, Objects and Plugins with horizontal lines and plain headings. Connection status appears beside the section title; port, loopback address and the start/stop button share a single line below it. Uncheck an object to hide it temporarily; rechecking displays its latest geometry and materials. Remove meshes withdraws all sources from the list and avatar preview. Subsequent live revisions keep them removed. To bring them back, restart the preview and use Update now in Blender. These controls affect the viewer's local preview and do not change the synchronization list or scene in Blender.

Visibility and removal survive source renames with plug-in 0.8.6+ and list reordering. Settings reset when a source stops being sent (for example, when disabled/removed in Blender), when stopping the bridge or changing accounts. Older plug-ins use names as their identity, so renaming starts a new entry.

Each object has its own Import button on its row, with no selection required. With plug-in 0.11.0+, it asks Blender to prepare the current object and all three lower LODs, then opens them in the normal mesh importer. All four levels are assigned automatically. All parts, weights, inverse binds, UVs, colors and image pixels belong to that draft; later live edits cannot alter a pending quote or upload. Existing drafts remain available, and the new draft is selected alone. Review the LODs, physics, scale, destination and permissions, calculate the cost, then confirm the upload normally. Opening the draft does not request a quote, charge money or create an inventory item.

Select a source in Blender's synchronization list and expand Import / LOD. Each source retains its own Medium, Low and Lowest settings in the .blend:

• Existing object: choose a mesh explicitly, or detect it by name suffix. Defaults are _medium, _low, _lowest, case insensitive. A trailing _high, .high or -high is removed before adding the configured suffix. Explicit assignment takes priority; hidden objects are supported.
• Automatic: reduce disposable copies of the current rest mesh with Blender's Decimate modifier. Set a percentage of High triangles (defaults: 50%, 25%, 12.5%) or an approximate triangle target for each level.
• Existing or automatic: the default; use an assigned/detected object, generating only when none exists. An invalid existing mesh reports an error instead of being silently replaced.

Existing levels must use the same armature and High's materials. Material slots are matched and reordered; omitted surfaces become empty geometry at that level. Incompatible or ambiguous slots are rejected. All levels share one validated joint/bind palette. Generation bakes current shape keys and geometry modifiers on copies at rest, retaining interpolated weights, UVs and material assignments. Original meshes, modifiers, keys, pose, selection and list flags stay intact.

In Block Viewer, select each LOD row to inspect its geometry and triangle count. The skinned preview's Test bend (°) slider bends elbows and knees to inspect deformations; it changes only the preview pose. Review the reductions visually, especially seams and small details, before confirming an import. Automatic triangle counts are approximate and may require adjusting the target.

Preparation waits for Blender's Object Mode, with an actionable error after 30 seconds; the viewer abandons an unanswered request after 180 seconds or a disconnect. Each bundle is bounded to 600,000 exported corners and 64 MiB. Older plug-ins can still synchronize live, but must be updated for this import workflow. A paused source can be imported without enabling its live preview.

The existing mesh upload format includes base colors and diffuse/base-color textures. PBR material assets require a separate material upload; the importer displays this limitation beside the frozen-source notice. The live preview continues to show its supported PBR materials.

Both packages contain the same rig, automatic weights, live materials and transport. Install only one format in each Blender profile; disable any older Block LiveMesh installation before switching between the two formats. Updating within the same format replaces the existing add-on. Blender 2.93 LTS is the minimum supported version; Blender 2.79 is not supported.

Developers can build either format from the repository root:

python blender/package.py .scratch/block-live-mesh-0.8.7.zip
python blender/package.py --legacy .scratch/block-live-mesh-0.8.7-legacy.zip

The extension ZIP has a root manifest and targets Blender 4.2+. The classic ZIP contains an block_live/ directory with bl_info and targets 2.93–4.1.

Create a rig and test T-shirt

In Blender's 3D view, open the sidebar (N) → Block → Skeleton, then expand Create an SL avatar. Click Create SL avatar rig to add a new armature at the 3D cursor. Leave Add rigged test T-shirt enabled to create a garment with it, or disable the option for the armature alone. Use Object Mode to create a starter. The operator supports Undo and never replaces existing scene objects.

The rig contains all 133 Second Life Bento bones and 26 Fitted Mesh collision bones, using the same avatar_skeleton.xml as Block Viewer. Original joint names, parents and rest positions are preserved. Bone collections separate the body, hands, face, wings, tail and other extensions in Blender 4.0+. Blender 2.93–3.x uses matching named pose groups and one armature layer per group. Body and hand sets are visible initially; enable other collections or layers in Armature Data Properties when needed. All 159 bones can deform meshes. Classic layer indices are recorded in the rig's block_bone_layers custom property.

The optional T-shirt has editable quad topology, open neck/hem/cuffs, a UV map, a fabric material, an Armature modifier and normalized vertex weights (up to four influences). It is selected when created: click Connect to Block Viewer to preview it. Creating a T-shirt adds it to the synchronization list, keeping existing entries, whether or not a connection is active. Pose the armature to inspect its weights in Blender; the viewer still receives the rest mesh and uses its own animations.

The starter respects the current Coordinates choice and scene unit scale. Its proportions are the standard SL rest skeleton, independent of your current account's shape. The shirt is sample geometry for testing weights and live edits; fit it to your intended body before using it as clothing. It includes no avatar body mesh. Optional IK controls can be added through the Controls category.

Skeleton visibility and hand/foot IK

Choose Avatar rig in Skeleton, or leave it empty to use the active armature or the active mesh's rig. The category shows separate toggles for the back/torso, head/neck, arms, legs, Bento fingers, face/eyes, wings, tail, hind limbs, Fitted Mesh volumes and IK controls. Show all / Hide all affect every bone. Enabling a part also reveals its containing collections/layers, without revealing unrelated hidden parts. These controls work in Edit Mode too. In front, Names, and Blender's rest/pose switch help inspect the skeleton. Visibility follows the current mode: Object/Pose uses pose visibility, while Edit Mode uses edit-bone visibility. Visibility changes display only; they do not disable deformation. Plug-in 0.6.2 corrects Blender 5's separate pose hide flag, so showing a part and hiding it again both affect the viewport.

Simple back and advanced Bento spine

In plug-in 0.7.0, Back / torso shows the three classic bones: mPelvis, mTorso and mChest. Head / neck has its own toggle. Showing the back always hides the four folded spine joints, including on existing rigs that previously showed everything. Hiding the back hides those joints too, so no overlapping spine bones remain on screen. Other parts keep their visibility.

Expand Advanced bones → Bento spine to show mSpine1 through mSpine4 explicitly. This section starts collapsed. Show all and the deform-bone operator still expose the complete rig. Existing scripted BODY operator calls remain supported as classic back plus head/neck.

The apparent three-way split of the lower back is intentional SL geometry. The official skeleton XML has this parent chain:

mPelvis → mSpine1 → mSpine2 → mTorso → mSpine3 → mSpine4 → mChest

Reading its rest coordinates shows that mSpine1 runs back down the pelvis segment and mSpine2 runs up again over the same 8.4 cm span. This produces three overlapping Blender bone drawings (mPelvis plus those two joints), rather than three successive lumbar vertebrae. The same arrangement occurs over mTorso with mSpine3 and mSpine4.

The official Bento spine guide places two extra joints between pelvis and torso and two between torso and chest. They permit more flexible custom models. Their folded neutral layout keeps the classic avatar's proportions, as described in the Bento release notes introducing them. Custom rigs can deliberately reposition and animate them. Avastar's display documentation similarly separates torso visibility from the advanced folded spine.

The viewer changes visibility only: it keeps all 159 deform bones, their parents, rest matrices, animation and existing weights. Hidden spine weights still transfer, normalize and export. This display action does not unfold or reparent joints. Custom joint-position overrides and Blender animation streaming remain outside the live bridge's current scope.

Hand/foot IK

In Controls, Create IK controls adds eight non-deforming target/pole bones and four independent two-bone IK chains. The 159 SL deformation bones retain their rest matrices and canonical joint names. The controls are optional, excluded from live export, and kept in a Block Viewer IK collection (layer 32 in Blender 2.93–3.x). Creating controls again is idempotent. Use a simple, editable SL armature; limbs already constrained by another rigging tool are rejected before adding controls.

Plug-in 0.8.5 gives IK controls clean, continuous custom-shape outlines: rounded hand frames, slim foot platforms with a heel arc, rounded elbow diamonds and knee circles with small center marks. Left controls are teal; right controls are coral, with brighter selection states. Decorative cages, arrows and 3D lettering have been removed. Blender 4.2+ uses a three-pixel native wire width; earlier versions use Blender's native custom-shape lines. Shape size follows limb proportions, independent of the tiny underlying helper bone's length. All eight outlines remain directly selectable. Hand frames lie flat in the palm's plane, with their long side pointing toward the fingers, and follow wrist rotation. Earlier vertical LiveMesh hand frames migrate automatically without rotating bones or changing a pose.

In Controls, adjust Handle size (0.4–3 times normal) for the current rig. In front keeps handles visible through the garment. The refresh icon rebuilds all eight IK widgets without resetting a pose or changing the solver. Selecting Target or Pole enters Pose Mode and selects the corresponding control; you can also click its custom shape directly in the viewport. The default elbow poles sit behind the arms at elbow height, about two upper arm lengths away. Each knee pole sits directly ahead of its own knee at knee height, about 0.6 thigh lengths away. Avatar facing is derived from SL joint geometry, so the native and -Y starter orientations behave consistently. The small sideways rest bend of SL legs no longer sends the poles across the body. When enabling IK on a clearly bent FK limb, its current bend plane is retained instead.

The solver is initialized geometrically in the pole plane. Shortest-arc bone rotations retain twist, and the pole angle is measured from the actual seeded bend, matching Blender's ConstrainPoleVector implementation. Moving only a foot target upward now bends its knee toward its pole throughout the lift and return. The original SL neutral leg splay shifts slightly into that forward plane when IK is enabled (about 2.5 cm at the knee); ankle targets, SL rest matrices, weights and live export stay fixed. Already-bent FK poses retain their visible shape when switching to IK.

For an older rig whose active knees still fold sideways, use Controls > Feet > Correct knee bend. It recalibrates only active foot IK chains, using their existing foot targets and pole positions. Those controls stay fixed while the knees return to the pole plane. This explicit correction updates the current pose and leaves animation keys untouched; file loading does not silently recalibrate existing rigs.

For an existing rig, Controls > Reposition poles applies the corrected placement without rebuilding controls, editing rest bones or changing the current IK/FK switches. This explicit action affects the current pose; it does not rewrite animation keys. Loading a file never repositions authored or animated poles automatically. Avastar's IK controls and pole-angle explanation describe the same distinction between endpoint targets and elbow/knee poles. The native Blender custom-shape display system keeps these shapes outside rendered geometry.

Existing LiveMesh rigs receive missing/older Block widgets on plug-in enable or file load. Hand-authored custom shapes are preserved during automatic migration and size changes; the explicit refresh action replaces them. Widget templates are unlinked datablocks, never scene meshes or synchronized objects. Existing poses, keyframes, rest bones, weights, constraints and live capture stay unchanged. Size is saved per armature object. Earlier Blender uses left/right bone groups for the same colors; 4.0+ uses pose-bone colors.

Enable each hand or foot independently. Target selects its control in Pose Mode: move it to position the wrist/ankle, rotate it to orient the hand/foot. Pole selects the elbow/knee direction control. IK does not stretch limbs; targets beyond their reach cannot be reached. Enabling snaps controls to the current FK pose; disabling bakes the visible limb pose back to FK. The straight SL T-pose uses a tiny local pose seed to avoid Blender's singular straight-chain solve; the SL rest skeleton stays unchanged. Native SL joint gaps can introduce pose differences of about one millimetre during switching. Use Pose Position and leave Edit Mode before switching IK.

These controls support fitting and weight inspection in Blender. The viewer continues receiving the rest mesh and playing its own avatar animations; Blender IK poses and animation playback are not streamed. This is a focused set of SL rigging tools, not an Avastar import/export or animation replacement.

Root / COG and look-at controls

Plug-in 0.8.0 adds optional pose controls under Controls (the former IK category). They work on existing simple SL rigs as well as the starter. Create them with the rig outside Edit Mode. Each creation supports Undo, preserves object selection and the previous mode, and is idempotent. A shared armature datablock is copied before controls are added. Conflicting bone names or existing constraints on driven joints are rejected before changing the rig.

What these helpers represent

Avastar distinguishes its deform skeleton from animator controls. Its animation manual describes Origin as scene placement for an entire character, excluded from its exported animation, and COG as movement around the center of gravity, mapped to the SL pelvis by Avastar's animation exporter. The Avastar Eye Rig manual describes independent targets for the classic eyes (mEyeLeft/mEyeRight) and the alternate Bento eyes (mFaceEyeAltLeft/mFaceEyeAltRight). Moving a target rotates the corresponding eyes toward it. A nearby target makes them converge more strongly. These targets are editing handles, not new SL joints.

Use Block's root and COG

Click Add root / COG. Root selects the global ring at the armature origin; move or rotate it to place the whole posed avatar in Blender. COG selects the diamond at the pelvis; it moves the body and rotates it around that pivot. Active hand/foot IK targets remain anchored relative to Root when COG moves. Root moves those targets with the character. Both creation orders (IK first or Root first) work. Existing look targets also follow Root.

The new bones are auroraPose.Root and auroraPose.COG, both non-deforming. A pose constraint connects COG to the pelvis without changing any SL rest matrix or parent. The original pelvis pose/keyframes remain intact. These are Block helpers, not Avastar rig data or the viewer's runtime mRoot.

Use classic and Bento gaze

Under Look at, create Classic eyes + and/or Bento eyes +. A rig without one of those complete pairs can still use the other. Each target starts ahead of the eyes at a distance derived from the rig's scale (about two metres on the standard starter). Focus starts disabled, preserving existing eye poses. Enable its checkbox and choose Target to enter Pose Mode and move the cross-shaped target. Classic and Bento controls are independent. Disabling focus retains the visible eye rotation for manual posing. The curved-arrow button recenters the target in front of the current head pose. The head itself does not automatically turn toward the target.

Skeleton → Root / COG controls and Look-at targets show/hide these helpers independently of deform bones and IK controls. Selecting a hidden helper reveals its group. Custom shapes are unlinked helper datablocks, not scene meshes. No geometry is added to the synchronized-object list.

All controls stay outside automatic weights, deform-weight transfer/cleanup and the live joint palette. The existing 159 SL bones, hierarchy and rest positions remain unchanged. These tools pose the character in Blender; Blender's current Root/COG/eye poses and their animation are not streamed or exported as SL animation by the live bridge. The viewer keeps animating the rest mesh itself. Only the supported SL bones should receive garment weights.

Automatic weight painting

Select your mesh objects and choose Avatar rig in Weights. The starter selects its newly created rig automatically. Leaving the field empty uses each mesh's existing armature, or the single selected armature. Under Automatic weights, click Recalculate weights in Object Mode or Weight Paint mode. This replaces the selected meshes' bone weights using Blender's native heat solver, keeps the strongest four influences and normalizes them. Undo restores the previous result. An existing Block connection immediately tracks these meshes and sends the updated weights. Existing list entries remain; paused objects keep their pause state.

SL body uses enabled classic body deform bones, excluding overlapping Bento and collision bones. All deform bones includes enabled Bento/custom deform bones, except collision volumes and the four overlapping Bento spine joints. The source rig's deform flags and rest pose are preserved. Empty counterpart groups are kept for Mirror modifiers. Non-bone groups, shape keys, UVs, selection and world placement are preserved; a mesh shared with another object becomes independent before its weights change.

The calculation runs on disposable mesh/rig copies in rest pose. If a solve leaves any vertex unweighted, no selected source mesh is changed. Check the topology and retry, or paint the problematic weights manually. Use editable objects with at most one Armature modifier.

Transfer and normalize weights

In Weights → Weight transfer, choose a Weight source mesh, then select the target meshes. The donor can remain selected; it is excluded from targets. Transfer weights replaces only target bone groups, binds the targets to Avatar rig (or their existing/donor rig), keeps the strongest four weights and normalizes them. Nearest surface interpolates weights on the closest donor triangle; Nearest vertex copies the closest donor vertex's weights. Matching uses world coordinates, including object transforms. Target matching uses the current shape-key fit, retaining original vertex indices and excluding target topology modifiers and armature posing. Max distance rejects any vertex too far from the source; zero is unlimited.

The donor is evaluated on a disposable copy, with shape keys and geometry modifiers but without armature posing. Bone aliases map through block_joint. Bento and Fitted Mesh deform weights are included; non-deforming IK controls are excluded. A donor without deform weights, an unweighted target vertex, a locked target bone group, or an exceeded distance rejects the entire selected batch before publishing any weight changes. Unlock target bone groups deliberately before replacing them.

Weight cleanup → Normalize to 4 weights cleans selected meshes' existing deform weights without a donor. Both operations support Undo and preserve non-bone mask groups, UVs, shape keys, placement, selection and Weight Paint mode. Shared target mesh data becomes independent. The donor stays unchanged. Connected target meshes are added to the live list without resuming paused entries, and weight changes trigger a new capture.

Live materials

Plug-in 0.8.5 requires Block Viewer with live PBR support. It recognizes the connected Principled BSDF of each material: base color, alpha, metallic, roughness, emission color/strength and backface culling. Older Principled input names and Separate RGB channel nodes are supported. Direct RGB/Value constants work too. Changing material parameters or assignments updates the preview without moving the mesh. Texture painting also captures continuously at the normal update interval.

The supported image maps are base color, tangent-space normal, metallic/ roughness and emission. Images are embedded from Blender's loaded pixel data; no paths are sent to the viewer. Metallic/roughness channels are packed automatically. Use a Normal Map node in Tangent space with strength 1; connect an image's Alpha output to Principled Alpha to use its transparency. Otherwise image alpha is ignored, as in Blender. Alpha is opaque or blended.

Use the mesh's active UV map, flat Image Texture nodes, Repeat extension and Linear interpolation. A Point Mapping node supports translation, scale and Z rotation. Metallic and roughness maps must share the same UV transform. Image color spaces are sRGB, Linear Rec.709/Linear or Non-Color/Raw (Blender 3.x names included); float images are read in any space. Each source image is limited to 16 megapixels and downsampled to at most 1024 pixels on its longest edge. At most 16 images and 16 MiB of RGBA pixels travel in one snapshot. Unchanged images reuse GPU slots; old materials/images remain until their last geometry reference is released. Unchanged image mip chains/staging are reused on the socket worker too; a temporary staging shortage retries automatically.

Bake procedural shaders, material groups and advanced Principled effects (coat, transmission, subsurface, sheen) to compatible images first. SL's PBR model does not represent every Blender shader input. When a material cannot be captured, the live preview keeps syncing the mesh in the material's viewport display color and the object's warning icon gives the reason; Import / LOD still rejects the material until it is fixed. Reload an externally edited image in Blender; Update now also refreshes image caches.

Current limits

• 32 enabled source objects and 600,000 exported corners. Transfer frames stay within 64 MiB; negotiated lossless compression accepts up to 256 MiB of decoded snapshot JSON. The plug-in compresses on its socket worker without reducing geometry or texture quality. A source that still exceeds the negotiated budget is omitted and gets its own warning; other valid sources keep updating. Paused entries remain in the list and do not count toward these limits.
• 110 weighted joints per source object and 32 nonempty material surfaces. Large surfaces and more than eight faces are split into render objects.
• Materials follow the supported PBR/image conventions above. Arbitrary Blender shader graphs and Blender animation playback are not transmitted.
• This previews the fit over the avatar and its existing outfit. It does not replace an inventory attachment or automatically hide body/outfit parts.
• Saving the .blend file does not save the connection. File loading and disabling the extension stop its worker.

The viewer retains the last valid geometry while a replacement is prepared. Invalid snapshots are rejected as a whole. Obsolete preview GPU buffers are freed when no draw object refers to them. Render objects occupy a private namespace and cannot be selected for simulator edits or touches. They are excluded from automatic hover calibration, so fitting preview shoes cannot change the hover height sent to the simulator.

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Deeper protocol, offline-validation, and contributor-depth sections are omitted here so this page stays readable.