# Run with: # blender --background --python emberscope-starter-freeform-v1.blender.py import json import math from pathlib import Path import bpy from mathutils import Matrix, Vector HERE = Path(__file__).resolve().parent data = json.loads((HERE / "emberscope-starter-freeform-v1.blender.json").read_text()) bpy.ops.object.select_all(action="SELECT") bpy.ops.object.delete() def mat(name, color, metallic=0.0, roughness=0.35, alpha=1.0): material = bpy.data.materials.new(name) material.use_nodes = True bsdf = material.node_tree.nodes.get("Principled BSDF") bsdf.inputs["Base Color"].default_value = color bsdf.inputs["Metallic"].default_value = metallic bsdf.inputs["Roughness"].default_value = roughness bsdf.inputs["Alpha"].default_value = alpha material.blend_method = "BLEND" if alpha < 1.0 else "OPAQUE" return material mirror_mat = mat("LWIR reflective mirrors", (0.38, 0.70, 1.0, 1.0), metallic=0.85, roughness=0.18) ray_mat = mat("schematic ray bundles", (1.0, 0.30, 0.18, 1.0), roughness=0.1) aperture_mat = mat("entrance aperture", (0.92, 0.96, 1.0, 1.0), roughness=0.2) sensor_mat = mat("sensor plane", (1.0, 0.80, 0.22, 0.74), metallic=0.2, roughness=0.2, alpha=0.74) package_mat = mat("package allowances", (0.35, 0.74, 0.42, 0.35), roughness=0.45, alpha=0.35) envelope_mat = mat("150 mm envelope reference", (1.0, 0.82, 0.24, 0.14), roughness=0.45, alpha=0.14) def rotation_matrix(tip_deg, tilt_deg): tx = math.radians(tip_deg) ty = math.radians(tilt_deg) rx = Matrix(((1, 0, 0), (0, math.cos(tx), -math.sin(tx)), (0, math.sin(tx), math.cos(tx)))) ry = Matrix(((math.cos(ty), 0, math.sin(ty)), (0, 1, 0), (-math.sin(ty), 0, math.cos(ty)))) return ry @ rx def poly_sag(x, y, surf): xn = x / surf["Rnorm"] yn = y / surf["Rnorm"] result = 0.0 idx = 0 for order in range(1, surf["poly_order"] + 1): for j in range(order + 1): i = order - j result += surf["poly_coeffs"][idx] * (xn ** i) * (yn ** j) idx += 1 return result def sag(x, y, surf): r2 = x * x + y * y R = surf["R"] k = surf["k"] denom = R * (1.0 + math.sqrt(max(0.0, 1.0 - (1.0 + k) * r2 / (R * R)))) return r2 / denom + poly_sag(x, y, surf) def add_mirror(surf): n_theta = 96 n_rad = 24 verts = [] faces = [] rot = rotation_matrix(surf["tip_deg"], surf["tilt_deg"]) pos = Vector(surf["position"]) for ir in range(n_rad): radius = (surf["diameter"] / 2.0) * ir / (n_rad - 1) for it in range(n_theta): theta = 2.0 * math.pi * it / n_theta x = radius * math.cos(theta) y = radius * math.sin(theta) z = sag(x, y, surf) verts.append(tuple(pos + rot @ Vector((x, y, z)))) for ir in range(n_rad - 1): for it in range(n_theta): a = ir * n_theta + it b = ir * n_theta + ((it + 1) % n_theta) c = (ir + 1) * n_theta + ((it + 1) % n_theta) d = (ir + 1) * n_theta + it faces.append((a, b, c, d)) mesh = bpy.data.meshes.new(surf["id"] + " mesh") mesh.from_pydata(verts, [], faces) mesh.update() obj = bpy.data.objects.new(surf["id"], mesh) bpy.context.collection.objects.link(obj) obj.data.materials.append(mirror_mat) def add_box(name, center, size, material): bpy.ops.mesh.primitive_cube_add(size=1.0, location=tuple(center)) obj = bpy.context.object obj.name = name obj.dimensions = tuple(size) bpy.ops.object.transform_apply(location=False, rotation=False, scale=True) obj.data.materials.append(material) return obj def add_curve(name, points, material, bevel_depth): curve = bpy.data.curves.new(name, "CURVE") curve.dimensions = "3D" curve.resolution_u = 2 curve.bevel_depth = bevel_depth poly = curve.splines.new("POLY") poly.points.add(len(points) - 1) for p, coords in zip(poly.points, points): p.co = (coords[0], coords[1], coords[2], 1.0) obj = bpy.data.objects.new(name, curve) bpy.context.collection.objects.link(obj) obj.data.materials.append(material) for surf in data["surfaces"]: add_mirror(surf) for component in data["components"]: geometry = component.get("geometry", {}) if component["type"] == "window" or component["type"] in {"electronics", "structure"}: add_box(component["id"], geometry["center_mm"], geometry["size_mm"], package_mat) elif component["type"] == "envelope_reference": box = add_box(component["id"], geometry["center_mm"], geometry["size_mm"], envelope_mat) box.display_type = "WIRE" elif component["type"] == "baffle": bpy.ops.mesh.primitive_cylinder_add( vertices=64, radius=geometry["diameter_mm"] / 2.0, depth=geometry["length_mm"], location=tuple(geometry["center_mm"]), ) obj = bpy.context.object obj.name = component["id"] obj.data.materials.append(package_mat) aperture = data["entrance_aperture"] bpy.ops.mesh.primitive_torus_add( major_radius=aperture["diameter"] / 2.0, minor_radius=0.35, location=tuple(aperture["center"]), ) bpy.context.object.name = "entrance aperture" bpy.context.object.data.materials.append(aperture_mat) sensor = data["image_sensor"] c = Vector(sensor["center"]) x = Vector(sensor["x_axis"]) * (sensor["width"] / 2.0) y = Vector(sensor["y_axis"]) * (sensor["height"] / 2.0) verts = [tuple(c - x - y), tuple(c + x - y), tuple(c + x + y), tuple(c - x + y)] mesh = bpy.data.meshes.new("image sensor mesh") mesh.from_pydata(verts, [], [(0, 1, 2, 3)]) mesh.update() sensor_obj = bpy.data.objects.new("image sensor / focal plane", mesh) bpy.context.collection.objects.link(sensor_obj) sensor_obj.data.materials.append(sensor_mat) for idx, ray in enumerate(data["ray_paths"]): add_curve(f"source_spec_ray_{idx:02d}", ray["points"], ray_mat, 0.16) bpy.ops.object.light_add(type="AREA", location=(90, -130, 125)) light = bpy.context.object light.name = "large softbox" light.data.energy = 500 light.data.size = 130 bpy.ops.object.camera_add(location=(130, -160, 105), rotation=(math.radians(62), 0, math.radians(42))) bpy.context.scene.camera = bpy.context.object bpy.context.scene.render.engine = "CYCLES" bpy.context.scene.cycles.samples = 96 bpy.context.scene.view_settings.view_transform = "Filmic" bpy.context.scene.view_settings.look = "Medium High Contrast" bpy.context.scene.render.resolution_x = 1800 bpy.context.scene.render.resolution_y = 1200 bpy.context.scene.render.filepath = str(HERE / "emberscope-starter-freeform-v1.blender-render.png") bpy.ops.render.render(write_still=True)