BlenderLens

Write a .glb, Y-up (-Y front becomes +Z), for a target engine; what it cannot load is refused, as is edit mode. Returns: the file read back, with warnings for the target. WHEN TO CALL: to deliver.

List a mesh's faces. Returns: each face's index, center, normal, side, area, material slot. WHEN TO CALL: for face indices; again after faces change.

Read one object in full. Returns: transform, bounds, properties, counts before and after modifiers, modifier settings by Blender's names, slots. WHEN TO CALL: before set_modifier.

Read the scene. Returns: file state, units, and each object's type, parent, location, dimensions, counts, materials, modifiers. WHEN TO CALL: before building; after not_found.

Report the attached Blender without starting one. Returns: the session (busy: what it runs), add-on, Blender, render_dir, recovery copies. WHEN TO CALL: first; after not_connected, connection_lost, busy.

Import a .glb, .gltf, .obj, .fbx, .stl or .ply, or append from a .blend what is named. Returns: what it added. WHEN TO CALL: for a reference, or to check an export.

Join meshes into the first, keeping each piece's materials and faces. Returns: the object, slots and their faces. WHEN TO CALL: to make one part of pieces.

List materials. Returns: each one's values (linear, as glTF) and users. WHEN TO CALL: before set_material, to reuse one.

Measure between objects' surfaces as exported, in world space, or cast a ray. Returns: per pair distance, closest points, touching, overlapping, overlap_faces, inside; ray object, location, normal, face. WHEN TO CALL: to fit parts, find gaps.

Open a .blend in place of the open file. Returns: the scene. WHEN TO CALL: to resume work.

Attach to the live Blender window or start a background one. Returns: the session. WHEN TO CALL: to pick a mode or file; else the first call attaches by BLENDERLENS_MODE.

Remove a modifier unapplied. Returns: the stack left, counts. WHEN TO CALL: to undo add_modifier.

Render a PNG of objects (and children) or all visible geometry, framed, others hidden, the scene unchanged. Returns: its path (open it, or inline). WHEN TO CALL: after each build step.

Run Python in Blender (bpy, bmesh, mathutils); names persist; set result to return it. Returns: stdout, stderr, result. WHEN TO CALL: only for what no tool covers.

Run a .py file in Blender as run_python does, with args; its folder, and parents up to a blenderlens.toml, are importable afresh each run. Returns: result, stdout, stderr, objects added, removed, changed. WHEN TO CALL: to build a model from its script.

Save the open file. Returns: path, size. WHEN TO CALL: at milestones; before closing a background session.

Move objects into a collection. Returns: their collections. WHEN TO CALL: to group parts.

Create or update a material, optionally on an object or its picked faces; all its users change; '' clears an image or vertex_color. Returns: its values, slot, faces. WHEN TO CALL: after shaping.

Change a modifier's settings, place or visibility. Returns: as add_modifier. WHEN TO CALL: to tune one.

Rename or hide an object, or set its display or custom properties (exported as glTF extras). Returns: its state. WHEN TO CALL: to name, hide or tag parts.

Parent an object, or clear its parent. Returns: the transform. WHEN TO CALL: to assemble parts into one node tree.

Set an object's location, rotation, scale or dimensions; null keeps a component. Returns: the transform; after drop, landed_on and moved_by. WHEN TO CALL: to place parts.

Paint the faces picked (faces, facing) or all into a color attribute. Returns: faces painted, materials wired, and not_wired (setups not BlenderLens's). WHEN TO CALL: for colour without textures; exports as COLOR_0.

Step back through undo steps, one per call that changed something; Python references go stale. Returns: steps undone, counts, unsaved_changes. WHEN TO CALL: to take back calls that went wrong.

Unwrap a mesh into a UV map; projections are packed. Returns: islands, area used, overlapping and out-of-bounds faces, texel density (px/m at 1024). WHEN TO CALL: before texturing or baking; unwrap needs seams (edit_mesh mark_seams).