Initial MoonModel implementation

script/render_previews.py

@@ -0,0 +1,111 @@
+"""Render seven validation views of a generated 3MF with Blender.
+
+Usage: blender --background --python script/render_previews.py -- model.3mf output_dir
+"""
+
+import math
+import os
+import sys
+import zipfile
+import xml.etree.ElementTree as ET
+
+import bpy
+from mathutils import Vector
+
+
+def args():
+    marker = sys.argv.index("--")
+    return os.path.abspath(sys.argv[marker + 1]), os.path.abspath(sys.argv[marker + 2])
+
+
+source, output = args()
+os.makedirs(output, exist_ok=True)
+bpy.ops.object.select_all(action="SELECT")
+bpy.ops.object.delete(use_global=False)
+
+
+def import_3mf(path):
+    with zipfile.ZipFile(path) as package:
+        root = ET.fromstring(package.read("3D/3dmodel.model"))
+    namespace = {"m": "http://schemas.microsoft.com/3dmanufacturing/core/2015/02"}
+    materials = []
+    bases = root.find("m:resources/m:basematerials", namespace)
+    if bases is not None:
+        for base in bases:
+            color = base.attrib.get("displaycolor", "#B0B0B0").lstrip("#")[:6]
+            rgba = tuple(int(color[i:i+2], 16) / 255 for i in (0, 2, 4)) + (1.0,)
+            material = bpy.data.materials.new(base.attrib.get("name", "material"))
+            material.diffuse_color = rgba
+            materials.append(material)
+    for element in root.findall("m:resources/m:object", namespace):
+        mesh_node = element.find("m:mesh", namespace)
+        if mesh_node is None:
+            continue
+        vertices = [(float(v.attrib["x"]), float(v.attrib["y"]), float(v.attrib["z"]))
+                    for v in mesh_node.findall("m:vertices/m:vertex", namespace)]
+        faces = [(int(t.attrib["v1"]), int(t.attrib["v2"]), int(t.attrib["v3"]))
+                 for t in mesh_node.findall("m:triangles/m:triangle", namespace)]
+        data = bpy.data.meshes.new(element.attrib.get("name", "mesh"))
+        data.from_pydata(vertices, [], faces)
+        data.update()
+        obj = bpy.data.objects.new(element.attrib.get("name", "object"), data)
+        bpy.context.collection.objects.link(obj)
+        if materials and "pindex" in element.attrib:
+            obj.data.materials.append(materials[int(element.attrib["pindex"])])
+
+
+import_3mf(source)
+
+objects = [obj for obj in bpy.context.scene.objects if obj.type == "MESH"]
+if not objects:
+    raise RuntimeError(f"No mesh objects imported from {source}")
+
+corners = []
+for obj in objects:
+    corners.extend(obj.matrix_world @ Vector(corner) for corner in obj.bound_box)
+minimum = Vector((min(p.x for p in corners), min(p.y for p in corners), min(p.z for p in corners)))
+maximum = Vector((max(p.x for p in corners), max(p.y for p in corners), max(p.z for p in corners)))
+center = (minimum + maximum) / 2
+extent = max(maximum - minimum)
+
+world = bpy.context.scene.world
+world.color = (0.035, 0.035, 0.035)
+bpy.context.scene.render.engine = "BLENDER_EEVEE"
+bpy.context.scene.render.resolution_x = 700
+bpy.context.scene.render.resolution_y = 700
+bpy.context.scene.render.resolution_percentage = 100
+bpy.context.scene.render.image_settings.file_format = "PNG"
+bpy.context.scene.render.film_transparent = False
+
+camera_data = bpy.data.cameras.new("Validation camera")
+camera = bpy.data.objects.new("Validation camera", camera_data)
+bpy.context.collection.objects.link(camera)
+bpy.context.scene.camera = camera
+camera.data.type = "ORTHO"
+camera.data.ortho_scale = extent * 1.25
+
+for energy, direction in [(1800, Vector((1, -1, 2))), (900, Vector((-2, 1, 0.5)) )]:
+    light_data = bpy.data.lights.new(name="Area", type="AREA")
+    light_data.energy = energy
+    light_data.shape = "DISK"
+    light_data.size = extent
+    light = bpy.data.objects.new(name="Area", object_data=light_data)
+    light.location = center + direction.normalized() * extent * 2
+    bpy.context.collection.objects.link(light)
+
+views = {
+    "front": Vector((0, -1, 0)),
+    "back": Vector((0, 1, 0)),
+    "left": Vector((-1, 0, 0)),
+    "right": Vector((1, 0, 0)),
+    "top": Vector((0, 0, 1)),
+    "bottom": Vector((0, 0, -1)),
+    "iso": Vector((1, -1, 0.8)).normalized(),
+}
+for name, direction in views.items():
+    camera.location = center + direction * extent * 3
+    camera.rotation_euler = (center - camera.location).to_track_quat("-Z", "Y").to_euler()
+    bpy.context.scene.render.filepath = os.path.join(output, f"{name}.png")
+    bpy.ops.render.render(write_still=True)
+
+print(f"Rendered {len(views)} views to {output}")