P21: PHYSICS SIMULATION

ID: P21 | Кластер: Simulation | Сложность: ⭐⭐⭐ | Теги: #physics #rigid-body #cloth #fluid #collision #cache

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🎯 ЦЕЛЬ

Симуляции Rigid Body / Cloth / Fluid: настройка, бейк кэша, экспорт Alembic

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📝 ПРОМПТ (РУС)

Настрой симуляцию [TYPE: RIGID/CLOTH/FLUID] для "[OBJECT]":
Параметры: [mass/friction/damping/resolution]
Кэш: DISK CACHE [start-end], запеки
Экспорт: Alembic при нужде

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📝 ПРОМПТ (ENG)

Setup [TYPE: RIGID/CLOTH/FLUID] simulation for "[OBJECT]":
Params: [mass/friction/damping/resolution]
Cache: DISK CACHE [start-end], bake it
Export: Alembic if needed

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🔧 MCP: execute_blender_code

import bpy

def setup_rigid_body(obj_name, body_type='ACTIVE', mass=1.0, friction=0.5, restitution=0.2):
    obj = bpy.data.objects.get(obj_name)
    if not obj:
        raise ValueError(f"Object {obj_name} not found")
    bpy.context.view_layer.objects.active = obj
    bpy.ops.rigidbody.object_add(type=body_type)
    rb = obj.rigid_body
    rb.mass = mass
    rb.friction = friction
    rb.restitution = restitution
    rb.collision_shape = 'CONVEX_HULL'
    return {"rigid_body": obj_name, "type": body_type}

def setup_cloth(obj_name, pin_group=None, quality=5):
    obj = bpy.data.objects.get(obj_name)
    bpy.context.view_layer.objects.active = obj
    mod = obj.modifiers.new("Cloth", 'CLOTH')
    s = mod.settings
    s.quality = quality
    s.mass = 0.3
    s.air_damping = 1.0
    if pin_group:
        s.vertex_group_mass = pin_group
    # Collision
    mod.collision_settings.use_collision = True
    mod.collision_settings.thickness_outer = 0.01
    return {"cloth": obj_name}

def bake_cache(frame_start=1, frame_end=250, cache_type='ALL'):
    bpy.context.scene.frame_start = frame_start
    bpy.context.scene.frame_end = frame_end
    bpy.ops.ptcache.bake_all(bake=True)
    return {"baked": f"{frame_start}-{frame_end}"}

def export_alembic(objects, filepath, start=1, end=250):
    bpy.ops.object.select_all(action='DESELECT')
    for o in objects:
        bpy.data.objects.get(o).select_set(True)
    bpy.ops.wm.alembic_export(
        filepath=filepath, selected=True,
        start=start, end=end, flatten=True, subsamples=4)
    return {"alembic": filepath}

# setup_rigid_body("Crate", mass=2.0)
# setup_cloth("Flag", pin_group="Pin", quality=6)
# bake_cache(1, 120)

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📊 ТИПЫ СИМУЛЯЦИЙ

Тип	Модификатор	Кэш	Экспорт
Rigid Body	RigidBody world	Point Cache	Alembic
Cloth	CLOTH	Point Cache	Alembic / MDD
Fluid (Mantaflow)	FLUID domain/flow	OpenVDB	VDB sequence
Particles	PARTICLE_SYSTEM	Point Cache	Alembic
Soft Body	SOFT_BODY	Point Cache	Alembic

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⚠️ ОШИБКИ

Ошибка	Решение
Объекты проваливаются	Увеличь Substeps (Scene → Rigid Body World → Steps), проверь Scale applied
Cloth взрывается	Уменьши mass, увеличь quality, проверь self-collision distance
Кэш не бейкится	Cache Type = All, путь записи доступен, Disk Cache включён

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🔗 СВЯЗИ

• Прочие в категории «Промпты»: P45: GEOMETRY NODES SIMULATION ZONES, P47: ALEMBIC CACHE PIPELINE, P03: MODIFIERS STACK, P22: PARTICLE SYSTEMS, P01: PRIMITIVE CREATION BASICS
• По темам: P02: BOOLEAN OPERATIONS, P04: MESH EDITING (BMESH), P05: UV UNWRAPPING STRATEGIES
• Теги: #cache, #cloth, #clothing, #collision, #fluid, #physics, #prompt, #rigid, #rigid-body, #simulation