# Stage 38 (read-only): clay render, to settle whether the remaining speckle is GEOMETRY or PAINT.
#
#   blender --background --python 38_clay.py -- <blend> <out_dir>
#
# The lane README's own advice: a clay render drops the material, and it is the only reliable way
# to tell a mesh defect from a painted one. Several dead ends here came from mistaking painted
# shadow for a dent and vice versa. Same cameras as 09_beauty so the frames line up.
import bpy, sys, math, os
from mathutils import Vector, Euler

argv = sys.argv[sys.argv.index("--") + 1:]
BLEND, OUT = argv[0], os.path.abspath(argv[1])
os.makedirs(OUT, exist_ok=True)

bpy.ops.wm.open_mainfile(filepath=BLEND)
for o in list(bpy.data.objects):
    if o.type in ('LIGHT', 'CAMERA'):
        bpy.data.objects.remove(o, do_unlink=True)
ob = max([o for o in bpy.data.objects if o.type == 'MESH'], key=lambda o: len(o.data.vertices))

clay = bpy.data.materials.new("clay")
clay.use_nodes = True
bsdf = clay.node_tree.nodes["Principled BSDF"]
bsdf.inputs["Base Color"].default_value = (0.62, 0.62, 0.62, 1)
bsdf.inputs["Roughness"].default_value = 0.55
if "Metallic" in bsdf.inputs:
    bsdf.inputs["Metallic"].default_value = 0.0
clay.use_backface_culling = False
ob.data.materials.clear()
ob.data.materials.append(clay)

sc = bpy.context.scene
sc.render.engine = 'BLENDER_EEVEE'
sc.render.resolution_x = sc.render.resolution_y = 1200
wd = bpy.data.worlds.new("w")
wd.use_nodes = True
wd.node_tree.nodes["Background"].inputs[0].default_value = (0.20, 0.20, 0.22, 1)
sc.world = wd


def sun(rot, e):
    ld = bpy.data.lights.new("s", 'SUN')
    ld.energy = e
    ld.use_shadow = False
    lo = bpy.data.objects.new("s", ld)
    lo.rotation_euler = rot
    bpy.context.collection.objects.link(lo)


sun(Euler((math.radians(55), 0, math.radians(-35))), 2.6)
sun(Euler((math.radians(120), 0, math.radians(150))), 1.1)
sun(Euler((math.radians(85), 0, math.radians(35))), 0.9)

cam = bpy.data.cameras.new("c")
cam.lens = 70
cob = bpy.data.objects.new("c", cam)
bpy.context.collection.objects.link(cob)
sc.camera = cob
for name, loc, rot in [
    ("full_front", Vector((0.0, -2.05, 0.50)), Euler((math.radians(90), 0, 0))),
    ("chest", Vector((0.0, -0.85, 0.70)), Euler((math.radians(90), 0, 0))),
    ("hip", Vector((0.0, -0.85, 0.46)), Euler((math.radians(90), 0, 0))),
    ("thigh", Vector((0.0, -0.70, 0.33)), Euler((math.radians(90), 0, 0))),
]:
    cob.location = loc
    cob.rotation_euler = rot
    sc.render.filepath = os.path.join(OUT, f"{name}.png")
    bpy.ops.render.render(write_still=True)
    print(f"clay {name}", flush=True)
print("CLAY_DONE")