"""Renders the rigged carousel posed through its handles, and a second pass with the joints drawn as markers
(bones do not render, so sticks and balls stand in for them). compose_rig_preview.py lays the two over each other.

    blender.exe -b --python-exit-code 1 --python render_rig_preview.py
"""
import bpy, bmesh, math, os
from mathutils import Vector, Matrix

HERE = os.path.dirname(os.path.abspath(__file__))
OUT = os.path.dirname(HERE)
PREV = os.path.join(OUT, "previews")
bpy.ops.wm.open_mainfile(filepath=os.path.join(OUT, "DockArm_Carousel_Rigged.blend"))
sc = bpy.context.scene
vl = bpy.context.view_layer
rig = bpy.data.objects["DockArm_Rig"]
P = rig.pose.bones
P["Turret"].rotation_euler.y = math.radians(-12)
P["CTRL_Arm1_Hoist"]["reach_in"] = 2.34
P["CTRL_Arm1_Hoist"].location.y = 8.0                 # arm 1 on its way into the pool: the boom joint at work
P["CTRL_Arm3_Hoist"].location.y = 5.3
P["CTRL_Arm3_Claws"].rotation_euler.x = math.radians(25)
rig.update_tag(); vl.update()
E = rig.evaluated_get(bpy.context.evaluated_depsgraph_get()).pose.bones

def emit(name, col):
    m = bpy.data.materials.new(name)
    m.use_nodes = True
    b = m.node_tree.nodes["Principled BSDF"]
    b.inputs["Base Color"].default_value = (0, 0, 0, 1)
    b.inputs["Emission Color"].default_value = col + (1,)
    b.inputs["Emission Strength"].default_value = 3.0
    return m
M_JOINT, M_BONE, M_CTRL = emit("_joint", (1.0, 0.42, 0.03)), emit("_bone", (1.0, 0.85, 0.2)), emit("_ctrl", (0.15, 1.0, 0.35))
bm = bmesh.new()
def stick(a, b, r, mi, seg=8):
    d = b - a
    if d.length < 1e-6:
        return
    g = bmesh.ops.create_cone(bm, cap_ends=True, segments=seg, radius1=r, radius2=r, depth=d.length,
                              matrix=Matrix.Translation((a + b) / 2) @ d.to_track_quat('Z', 'Y').to_matrix().to_4x4())
    for f in {f for v in g["verts"] for f in v.link_faces}:
        f.material_index = mi
def ball(p, r, mi):
    g = bmesh.ops.create_uvsphere(bm, u_segments=14, v_segments=8, radius=r, matrix=Matrix.Translation(p))
    for f in {f for v in g["verts"] for f in v.link_faces}:
        f.material_index = mi
for pb in E:
    b = rig.data.bones[pb.name]
    if b.use_deform and "_Hose" in pb.name:
        continue                                   # the hose fan bones sit on the joints they shadow
    if b.use_deform:
        big = pb.name.endswith(("_Boom", "_Upper", "_Lower", "_Head")) or pb.name == "Turret"
        stick(pb.head.copy(), pb.tail.copy(), 0.03 if big else 0.015, 1)
        ball(pb.head.copy(), 0.11 if big else 0.05, 0)
    elif pb.name.startswith("CTRL_"):
        M = pb.matrix
        if pb.name.endswith("_Hoist"):
            c = [M @ Vector((x, 0, 1.30 + z)) for x, z in ((-0.22, -0.22), (0.22, -0.22), (0.22, 0.22), (-0.22, 0.22))]
        else:
            c = [M @ Vector((0.15 * math.cos(2 * math.pi * i / 16), 0, 0.15 * math.sin(2 * math.pi * i / 16))) for i in range(16)]
        for i in range(len(c)):
            stick(c[i], c[(i + 1) % len(c)], 0.018, 2, 6)
me = bpy.data.meshes.new("_markers")
bm.to_mesh(me); bm.free()
for m in (M_JOINT, M_BONE, M_CTRL):
    me.materials.append(m)
markers = bpy.data.objects.new("_markers", me)
sc.collection.objects.link(markers)

cam = sc.camera
def look(loc, tgt, lens):
    cam.location = loc
    cam.rotation_euler = (Vector(tgt) - Vector(loc)).to_track_quat('-Z', 'Y').to_euler()
    cam.data.lens = lens
for _eng in ('BLENDER_EEVEE', 'BLENDER_EEVEE_NEXT'):       # joint diagrams: EEVEE is enough (the model file itself is set to Cycles since 2026-10-13)
    try:
        sc.render.engine = _eng
        break
    except Exception:
        continue
try:
    sc.eevee.taa_render_samples = 48
except Exception:
    pass
models = [o for o in bpy.data.objects if o.type == 'MESH' and o.name.startswith("SK_")]
for tag, loc, tgt, lens in (("above", (9.5, -10.5, 6.5), (0.2, -0.6, -1.6), 30), ("below", (10.5, -14.0, -6.2), (0.9, -1.6, -2.0), 28)):
    look(loc, tgt, lens)
    markers.hide_render = True
    for o in models:
        o.hide_render = False
    sc.render.film_transparent = False
    sc.render.image_settings.color_mode = 'RGB'
    sc.render.filepath = os.path.join(PREV, "_rig_%s_model.png" % tag)
    bpy.ops.render.render(write_still=True)
    markers.hide_render = False
    for o in models:
        o.hide_render = True
    sc.render.film_transparent = True
    sc.render.image_settings.color_mode = 'RGBA'
    sc.render.filepath = os.path.join(PREV, "_rig_%s_markers.png" % tag)
    bpy.ops.render.render(write_still=True)
print("RIG PREVIEW PASSES DONE")