"""Preview renders of the Manta: studio-in-water look (dark blue world, sun from above, rim lights). Not part of the export:
camera, lights and world live in the collection "_preview" (hidden from the export).
Run in the open Blender: exec with g["VIEWS"] = [...] and g["ENGINE"] = 'BLENDER_EEVEE' / 'CYCLES'."""
import bpy, math, os
from mathutils import Vector, Euler
OUT = r"D:\HADAL - The Descent\models\tender-manta\previews"
VIEWS = globals().get("VIEWS", ["hero"])
ENGINE = globals().get("ENGINE", "BLENDER_EEVEE")
TAG = globals().get("TAG", "v01")
RES = globals().get("RES", (1400, 900))
SAMPLES = globals().get("SAMPLES", 64)

sc = bpy.context.scene
pc = bpy.data.collections.get("_preview")
if pc is None:
    pc = bpy.data.collections.new("_preview"); sc.collection.children.link(pc)
def obj(name, data=None):
    o = bpy.data.objects.get(name)
    if o is None:
        o = bpy.data.objects.new(name, data); pc.objects.link(o)
    return o
cam = obj("_PrevCam", bpy.data.cameras.get("_PrevCam") or bpy.data.cameras.new("_PrevCam"))
sc.camera = cam
def light(name, kind, energy, color, rot, loc=(0, 0, 0), size=1.0):
    ld = bpy.data.lights.get(name) or bpy.data.lights.new(name, kind)
    ld.energy = energy; ld.color = color
    if kind == 'SUN':
        ld.angle = math.radians(6)
    else:
        ld.shape = 'DISK'; ld.size = size
    o = obj(name, ld); o.rotation_euler = Euler(rot); o.location = loc
light("_PrevSun", 'SUN', 3.2, (0.80, 0.92, 1.0), (math.radians(20), math.radians(-12), 0))
light("_PrevRim", 'AREA', 900, (0.55, 0.75, 1.0), (math.radians(-65), 0, math.radians(200)), loc=(-4, 8, 5), size=6)
light("_PrevFill", 'AREA', 350, (0.70, 0.85, 1.0), (math.radians(70), 0, math.radians(-30)), loc=(6, -6, -2), size=6)
w = bpy.data.worlds.get("_PrevWorld") or bpy.data.worlds.new("_PrevWorld")
w.use_nodes = True
bg = w.node_tree.nodes.get("Background")
bg.inputs[0].default_value = (0.012, 0.045, 0.075, 1); bg.inputs[1].default_value = 1.0
sc.world = w
sc.render.engine = ENGINE
sc.render.resolution_x, sc.render.resolution_y = RES
sc.render.resolution_percentage = 100
sc.view_settings.view_transform = 'AgX'
sc.view_settings.look = 'AgX - Medium High Contrast' if 'AgX - Medium High Contrast' in [i.identifier for i in bpy.types.ColorManagedViewSettings.bl_rna.properties['look'].enum_items] else 'None'
if ENGINE == 'CYCLES':
    sc.cycles.samples = SAMPLES
    sc.cycles.use_denoising = True
    prefs = bpy.context.preferences.addons['cycles'].preferences
    sc.cycles.device = 'CPU'
    for kind in ('OPTIX', 'CUDA', 'HIP', 'ONEAPI'):          # this PC bakes and renders on HIP
        try:
            prefs.compute_device_type = kind
        except Exception:
            continue
        prefs.refresh_devices()
        if any(d.type == kind for d in prefs.devices):
            for d in prefs.devices:
                d.use = d.type == kind
            sc.cycles.device = 'GPU'
            break
for c in ("MANTA | Collision (UCX)", "MANTA | Sockets"):
    if bpy.data.collections.get(c):
        bpy.data.collections[c].hide_render = True
# views: (location, look-at, lens)
V = {
    "hero": ((7.6, -9.0, 4.6), (0.0, -0.6, -0.1), 50),
    "ref": ((-7.0, -9.5, 6.5), (0.0, -0.2, -0.2), 50),          # the reference's angle: nose toward the camera, starboard side
    "side": ((-13.0, -0.2, 0.0), (0.0, -0.2, 0.0), 50),
    "top": ((0.0, -0.2, 14.0), (0.0, -0.2, 0.0), 45),
    "front": ((1.5, -11.0, -0.3), (0.0, -2.5, -0.2), 50),
    "stern": ((-5.5, 8.5, 2.6), (0.0, 1.5, 0.0), 50),
    "cabin": ((2.2, -5.0, -0.6), (0.0, -2.6, -0.2), 35),
    "under": ((4.5, -6.5, -5.5), (0.0, -0.2, -0.4), 50),
    "clips": ((2.0, -2.2, 3.3), (0.0, -0.09, 1.2), 50),
}
for name in VIEWS:
    loc, at, lens = V[name]
    cam.location = loc
    d = Vector(at) - Vector(loc)
    cam.rotation_euler = d.to_track_quat('-Z', 'Y').to_euler()
    cam.data.lens = lens
    if name == "top":
        cam.rotation_euler = Euler((0, 0, 0))
    sc.render.filepath = os.path.join(OUT, "%s_%s.png" % (TAG, name))
    bpy.ops.render.render(write_still=True)