"""Original sample furniture, glTF round trip, named material mapping and Cycles renders. Run with Blender --background --factory-startup --python build_study.py. No external meshes, textures, HDRIs, or client files are used. """ from pathlib import Path import bpy import json import math from mathutils import Vector OUT = Path(__file__).resolve().parent OUT.mkdir(exist_ok=True, parents=True) bpy.ops.object.select_all(action='SELECT') bpy.ops.object.delete(use_global=False) IDS = { 'wood_oak_01': (0.42, 0.24, 0.095, 1), 'metal_powder_graphite': (0.035, 0.045, 0.05, 1), 'fabric_boucle_forest': (0.10, 0.21, 0.15, 1), } placeholders = {} for name, color in IDS.items(): mat = bpy.data.materials.new(name) mat.diffuse_color = color mat.use_nodes = True mat.node_tree.nodes['Principled BSDF'].inputs['Base Color'].default_value = color placeholders[name] = mat def block(name, position, dimensions, material_id, radius=0.008, segments=4): bpy.ops.mesh.primitive_cube_add(size=1, location=position) ob = bpy.context.object ob.name = name ob.dimensions = dimensions bpy.ops.object.transform_apply(location=False, rotation=False, scale=True) bevel = ob.modifiers.new('Soft manufactured edges', 'BEVEL') bevel.width = radius bevel.segments = segments bevel.limit_method = 'ANGLE' bpy.ops.object.modifier_apply(modifier=bevel.name) ob.data.materials.append(placeholders[material_id]) for poly in ob.data.polygons: poly.use_smooth = True weighted = ob.modifiers.new('Weighted corner normals', 'WEIGHTED_NORMAL') weighted.keep_sharp = True bpy.ops.object.modifier_apply(modifier=weighted.name) return ob # Slatted oak deck and lower support rails, dimensions in metres. for i in range(6): block(f'Oak deck slat {i+1:02}', (0, -0.1825+i*0.073, 0.408), (1.42, 0.061, 0.036), 'wood_oak_01', 0.007) for y in (-0.135, 0.135): block('Oak underside support', (0, y, 0.373), (1.25, 0.045, 0.039), 'wood_oak_01', 0.006) for x in (-0.585, 0.585): block('Graphite top crossbar', (x, 0, 0.348), (0.037, 0.356, 0.030), 'metal_powder_graphite', 0.005) for y in (-0.16, 0.16): ob = block('Graphite leg', (x, y, 0.181), (0.033, 0.033, 0.342), 'metal_powder_graphite', 0.006) block('Floor glide', (x, y, 0.009), (0.035, 0.035, 0.018), 'metal_powder_graphite', 0.006) # Rounded upholstered pad leaves an oak tray-like seat section exposed. block('Forest boucle cushion', (0.215, 0, 0.474), (0.925, 0.405, 0.095), 'fabric_boucle_forest', 0.043, 10) # A small piping seam follows the rounded rectangular outline. curve = bpy.data.curves.new('Upholstery piping', 'CURVE') curve.dimensions = '3D' curve.bevel_depth = 0.002 curve.bevel_resolution = 3 spline = curve.splines.new('POLY') points = [] for cx, cy, start in ((0.635,0.155,0),(-0.205,0.155,90),(-0.205,-0.155,180),(0.635,-0.155,270)): for j in range(13): a = math.radians(start+j*90/12) points.append((cx+0.037*math.cos(a),cy+0.037*math.sin(a),0.474,1)) spline.points.add(len(points)-1) for p, co in zip(spline.points, points): p.co = co spline.use_cyclic_u = True seam = bpy.data.objects.new('Cushion stitched piping', curve) bpy.context.collection.objects.link(seam) seam.data.materials.append(placeholders['fabric_boucle_forest']) bpy.context.view_layer.objects.active = seam seam.select_set(True) bpy.ops.object.convert(target='MESH') # Export original geometry as glTF, then deliberately start fresh and reimport it. bpy.ops.object.select_all(action='SELECT') bpy.ops.export_scene.gltf(filepath=str(OUT/'original-bench.glb'), export_format='GLB', use_selection=True, export_materials='EXPORT') bpy.ops.wm.read_factory_settings(use_empty=True) bpy.ops.import_scene.gltf(filepath=str(OUT/'original-bench.glb')) model_objects = [o for o in bpy.context.scene.objects if o.type == 'MESH'] def cycle_material(identifier): mat = bpy.data.materials.new('cycles__'+identifier) mat.use_nodes = True n = mat.node_tree.nodes links = mat.node_tree.links bs = n.get('Principled BSDF') bs.inputs['Base Color'].default_value = IDS[identifier] tex = n.new('ShaderNodeTexCoord') noise = n.new('ShaderNodeTexNoise') links.new(tex.outputs['Generated'], noise.inputs['Vector']) bump = n.new('ShaderNodeBump') links.new(noise.outputs['Fac'], bump.inputs['Height']) links.new(bump.outputs['Normal'], bs.inputs['Normal']) if identifier.startswith('wood'): mapping = n.new('ShaderNodeVectorMath') mapping.operation = 'MULTIPLY' mapping.inputs[1].default_value = (2, 60, 18) links.new(tex.outputs['Generated'], mapping.inputs[0]) links.new(mapping.outputs['Vector'], noise.inputs['Vector']) noise.inputs['Scale'].default_value = 2.7 noise.inputs['Detail'].default_value = 3 noise.inputs['Roughness'].default_value = 0.68 ramp = n.new('ShaderNodeValToRGB') ramp.color_ramp.elements[0].position = 0.12 ramp.color_ramp.elements[0].color = (0.20,0.085,0.025,1) ramp.color_ramp.elements[1].position = 0.90 ramp.color_ramp.elements[1].color = (0.55,0.34,0.14,1) links.new(noise.outputs['Fac'], ramp.inputs['Fac']) links.new(ramp.outputs['Color'], bs.inputs['Base Color']) bs.inputs['Roughness'].default_value = 0.36 bump.inputs['Strength'].default_value = 0.17 bump.inputs['Distance'].default_value = 0.0007 elif identifier.startswith('fabric'): noise.inputs['Scale'].default_value = 185 noise.inputs['Detail'].default_value = 2 bs.inputs['Roughness'].default_value = 0.87 bs.inputs['Sheen Weight'].default_value = 0.28 bump.inputs['Strength'].default_value = 0.6 bump.inputs['Distance'].default_value = 0.0014 ramp = n.new('ShaderNodeValToRGB') ramp.color_ramp.elements[0].color = (0.033,0.095,0.052,1) ramp.color_ramp.elements[1].color = (0.17,0.29,0.18,1) links.new(noise.outputs['Fac'], ramp.inputs['Fac']) links.new(ramp.outputs['Color'], bs.inputs['Base Color']) else: bs.inputs['Metallic'].default_value = 0.48 bs.inputs['Roughness'].default_value = 0.33 noise.inputs['Scale'].default_value = 220 bump.inputs['Strength'].default_value = 0.10 bump.inputs['Distance'].default_value = 0.0003 return mat registry = {key: cycle_material(key) for key in IDS} mapping_log = [] for ob in model_objects: for slot in ob.material_slots: source_id = slot.material.name if source_id not in registry: raise RuntimeError('Unmapped glTF material ID: '+source_id) mapping_log.append({'object':ob.name,'source_material_id':source_id, 'cycles_material':registry[source_id].name}) slot.material = registry[source_id] scene = bpy.context.scene scene.render.engine = 'CYCLES' scene.cycles.samples = 96 scene.cycles.use_denoising = True scene.cycles.max_bounces = 8 scene.render.resolution_x = 1400 scene.render.resolution_y = 1000 scene.render.resolution_percentage = 100 scene.render.image_settings.file_format = 'PNG' scene.render.image_settings.color_mode = 'RGBA' scene.render.film_transparent = True scene.view_settings.view_transform = 'AgX' scene.view_settings.exposure = 0 scene.world = bpy.data.worlds.new('Studio world') scene.world.use_nodes = True scene.world.node_tree.nodes['Background'].inputs['Color'].default_value = (0.7,0.8,1.0,1) scene.world.node_tree.nodes['Background'].inputs['Strength'].default_value = 0.20 def aim(ob, target): ob.rotation_euler = (Vector(target)-ob.location).to_track_quat('-Z','Y').to_euler() for name, pos, power, size, color in ( ('Key softbox', (0,-2,3), 450, 2.5, (1,0.91,0.80)), ('Fill softbox', (-2,1,1.7), 280, 2, (0.82,0.90,1)), ('Rim strip', (1.5,1.4,2.4), 450, 1.6, (1,1,1)), ): data = bpy.data.lights.new(name, 'AREA') data.energy, data.shape, data.size, data.color = power, 'DISK', size, color ob = bpy.data.objects.new(name, data) scene.collection.objects.link(ob) ob.location = pos aim(ob,(0,0,0.25)) bpy.ops.mesh.primitive_plane_add(size=200, location=(0,0,0)) floor = bpy.context.object floor.name = 'Transparent shadow catcher' floor.is_shadow_catcher = True camera_data = bpy.data.cameras.new('Product orbit camera') camera = bpy.data.objects.new('Product orbit camera',camera_data) scene.collection.objects.link(camera) scene.camera = camera camera_data.type = 'ORTHO' camera_data.ortho_scale = 1.95 angles = {'front':(2.5,-3,1.75),'reverse':(-2.7,2.8,1.6),'side':(-2.8,-3.8,1.25)} stats = {'blender_version':bpy.app.version_string,'original_sample':True, 'client_project':False,'source_format':'GLB','dimensions_m':[1.42,0.426,0.5215], 'mesh_objects':len(model_objects), 'triangles':sum(sum(len(p.vertices)-2 for p in o.data.polygons) for o in model_objects), 'material_ids':list(IDS),'unmapped_material_ids':[], 'renderer':'Cycles','samples':96,'resolution':[1400,1000], 'denoising':True,'color_management':'AgX, exposure 0', 'manual_compositing':False,'external_assets':False,'mapping':mapping_log, 'cameras':angles} (OUT/'study-settings.json').write_text(json.dumps(stats,indent=2)+'\n') for name, position in angles.items(): camera.location = position aim(camera,(0,0,0.265)) scene.render.filepath = str(OUT/f'bench-{name}.png') if name == 'front': scene.render.filepath = '//bench-front.png' bpy.ops.wm.save_as_mainfile(filepath=str(OUT/'bench-cycles-study.blend')) scene.render.filepath = str(OUT/f'bench-{name}.png') bpy.ops.render.render(write_still=True) print('STUDY_COMPLETE',json.dumps({k:stats[k] for k in ('mesh_objects','triangles','material_ids','unmapped_material_ids')}))