# SPDX-FileCopyrightText: 2011-2022 Blender Foundation
#
# SPDX-License-Identifier: Apache-2.0

from __future__ import annotations

import bpy
from bpy.props import (
    BoolProperty,
    CollectionProperty,
    EnumProperty,
    FloatProperty,
    IntProperty,
    PointerProperty,
    StringProperty,
)
from bpy.app.translations import (
    contexts as i18n_contexts,
    pgettext_n as n_,
    pgettext_rpt as rpt_,
)

from math import pi

# enums

from . import engine
from . import camera

enum_devices = (
    ('CPU', "CPU", "Use CPU for rendering"),
    ('GPU', "GPU Compute",
        "Use GPU compute device for rendering, configured in the system tab in the user preferences"),
)

enum_bvh_layouts = (
    ('BVH2', "BVH2", "", 1),
    ('EMBREE', "Embree", "", 4),
)

enum_bvh_types = (
    ('DYNAMIC_BVH', "Dynamic BVH", "Objects can be individually updated, at the cost of slower render time"),
    ('STATIC_BVH', "Static BVH", "Any object modification requires a complete BVH rebuild, but renders faster"),
)

enum_filter_types = (
    ('BOX', "Box", "Box filter"),
    ('GAUSSIAN', "Gaussian", "Gaussian filter"),
    ('BLACKMAN_HARRIS', "Blackman-Harris", "Blackman-Harris filter"),
)

enum_curve_shape = (
    ('RIBBONS',
     "Rounded Ribbons",
     "Render curves as flat ribbons with rounded normals, for fast rendering"),
    ('THICK',
     "3D Curves",
     "Render curves as circular 3D geometry, for accurate results when viewing closely"),
    ('THICK_LINEAR',
     "Linear 3D Curves",
     "Render curves as circular 3D geometry, with linear interpolation between control points, for fast rendering"),
)

enum_use_layer_samples = (
    ('USE', "Use", "Per render layer number of samples override scene samples"),
    ('BOUNDED', "Bounded", "Bound per render layer number of samples by global samples"),
    ('IGNORE', "Ignore", "Ignore per render layer number of samples"),
)


def enum_sampling_pattern(self, context):
    prefs = context.preferences
    use_debug = prefs.experimental.use_cycles_debug and prefs.view.show_developer_ui

    items = [
        ('AUTOMATIC',
         n_("Automatic"),
         n_("Use a blue-noise sampling pattern, which optimizes the frequency distribution of noise, for random sampling. For viewport rendering, optimize first sample quality for interactive preview"),
         5)]

    debug_items = [
        ('SOBOL_BURLEY',
         n_("Sobol-Burley"),
         n_("Use on-the-fly computed Owen-scrambled Sobol for random sampling"),
         0),
        ('TABULATED_SOBOL',
         n_("Tabulated Sobol"),
         n_("Use pre-computed tables of Owen-scrambled Sobol for random sampling"),
         1),
        ('BLUE_NOISE',
         n_("Blue-Noise (pure)"),
         n_("Use a blue-noise pattern, which optimizes the frequency distribution of noise, for random sampling"),
         2),
        ('BLUE_NOISE_FIRST',
         n_("Blue-Noise (first)"),
         n_("Use a blue-noise pattern for the first sample, then use Tabulated Sobol for the remaining samples, for random sampling"),
         3),
        ('BLUE_NOISE_ROUND',
         n_("Blue-Noise (round)"),
         n_("Use a blue-noise sequence with a length rounded up to the next power of 2, for random sampling"),
         4),
    ]

    non_debug_items = [
        ('TABULATED_SOBOL',
         n_("Classic"),
         n_("Use pre-computed tables of Owen-scrambled Sobol for random sampling"),
         1),
        ('BLUE_NOISE',
         n_("Blue-Noise"),
         n_("Use a blue-noise pattern, which optimizes the frequency distribution of noise, for random sampling"),
         2),
    ]

    if use_debug:
        return items + debug_items
    else:
        return items + non_debug_items


enum_emission_sampling = (
    ('NONE',
     'None',
     "Do not use this surface as a light for sampling",
     0),
    ('AUTO',
     'Auto',
     "Automatically determine if the surface should be treated as a light for sampling, based on estimated emission intensity",
     1),
    ('FRONT',
     'Front',
     "Treat only front side of the surface as a light, usually for closed meshes whose interior is not visible",
     2),
    ('BACK',
     'Back',
     "Treat only back side of the surface as a light for sampling",
     3),
    ('FRONT_BACK',
     'Front and Back',
     "Treat surface as a light for sampling, emitting from both the front and back side",
     4),
)

enum_volume_sampling = (
    ('DISTANCE',
     "Distance",
     "Use distance sampling, best for dense volumes with lights far away"),
    ('EQUIANGULAR',
     "Equiangular",
     "Use equiangular sampling, best for volumes with low density with light inside or near the volume"),
    ('MULTIPLE_IMPORTANCE',
     "Multiple Importance",
     "Combine distance and equi-angular sampling for volumes where neither method is ideal"),
)

enum_volume_interpolation = (
    ('LINEAR', "Linear", "Good smoothness and speed"),
    ('CUBIC', "Cubic", "Smoothed high quality interpolation, but slower")
)

enum_world_mis = (
    ('NONE',
     "None",
     "Don't sample the background, faster but might cause noise for non-solid backgrounds"),
    ('AUTOMATIC',
     "Auto",
     "Automatically try to determine the best setting"),
    ('MANUAL',
     "Manual",
     "Manually set the resolution of the sampling map, higher values are slower and require more memory but reduce noise"))

enum_device_type = (
    ('CPU', "CPU", "CPU", 0),
    ('CUDA', "CUDA", "CUDA", 1),
    ('OPTIX', "OptiX", "OptiX", 3),
    ('HIP', "HIP", "HIP", 4),
    ('METAL', "Metal", "Metal", 5),
    ('ONEAPI', "oneAPI", "oneAPI", 6)
)

enum_texture_limit = (
    ('OFF', "No Limit", "No texture size limit", 0),
    ('128', "128", "Limit texture size to 128 pixels", 1),
    ('256', "256", "Limit texture size to 256 pixels", 2),
    ('512', "512", "Limit texture size to 512 pixels", 3),
    ('1024', "1024", "Limit texture size to 1024 pixels", 4),
    ('2048', "2048", "Limit texture size to 2048 pixels", 5),
    ('4096', "4096", "Limit texture size to 4096 pixels", 6),
    ('8192', "8192", "Limit texture size to 8192 pixels", 7),
)

enum_fast_gi_method = (
    ('REPLACE', "Replace", "Replace global illumination with ambient occlusion after a specified number of bounces"),
    ('ADD', "Add", "Add ambient occlusion to diffuse surfaces"),
)

# NOTE: Identifiers are expected to be an upper case version of identifiers from  `Pass::get_type_enum()`
enum_view3d_shading_render_pass = (
    ('', "General", ""),

    ('COMBINED', "Combined", "Show the Combined Render pass"),
    ('EMISSION', "Emission", "Show the Emission render pass"),
    ('BACKGROUND', "Background", "Show the Background render pass"),
    ('AO', "Ambient Occlusion", "Show the Ambient Occlusion render pass"),
    ('SHADOW_CATCHER', "Shadow Catcher", "Show the Shadow Catcher render pass"),

    ('', "Light", ""),

    ('DIFFUSE_DIRECT', "Diffuse Direct", "Show the Diffuse Direct render pass"),
    ('DIFFUSE_INDIRECT', "Diffuse Indirect", "Show the Diffuse Indirect render pass"),
    ('DIFFUSE_COLOR', "Diffuse Color", "Show the Diffuse Color render pass"),

    ('GLOSSY_DIRECT', "Glossy Direct", "Show the Glossy Direct render pass"),
    ('GLOSSY_INDIRECT', "Glossy Indirect", "Show the Glossy Indirect render pass"),
    ('GLOSSY_COLOR', "Glossy Color", "Show the Glossy Color render pass"),

    ('', "", ""),

    ('TRANSMISSION_DIRECT', "Transmission Direct", "Show the Transmission Direct render pass"),
    ('TRANSMISSION_INDIRECT', "Transmission Indirect", "Show the Transmission Indirect render pass"),
    ('TRANSMISSION_COLOR', "Transmission Color", "Show the Transmission Color render pass"),

    ('VOLUME_DIRECT', "Volume Direct", "Show the Volume Direct render pass"),
    ('VOLUME_INDIRECT', "Volume Indirect", "Show the Volume Indirect render pass"),

    ('', "Data", ""),

    ('POSITION', "Position", "Show the Position render pass"),
    ('NORMAL', "Normal", "Show the Normal render pass"),
    ('UV', "UV", "Show the UV render pass"),
    ('MIST', "Mist", "Show the Mist render pass"),
    ('DENOISING_ALBEDO', "Denoising Albedo", "Albedo pass used by denoiser"),
    ('DENOISING_NORMAL', "Denoising Normal", "Normal pass used by denoiser"),
    ('SAMPLE_COUNT', "Sample Count", "Per-pixel number of samples"),
)

enum_view3d_debug_render_pass = (
    ('VOLUME_SCATTER', "Volume Scatter", "Show the contribution of scattered ray in volume"),
    ('VOLUME_TRANSMIT', "Volume Transmit", "Show the contribution of transmitted ray in volume"),
    ('VOLUME_MAJORANT', "Volume Majorant", "Show the majorant transmittance of the volume")
)

enum_guiding_distribution = (
    ('PARALLAX_AWARE_VMM', "Parallax-Aware VMM", "Use Parallax-aware von Mises-Fisher models as directional distribution", 0),
    ('DIRECTIONAL_QUAD_TREE', "Directional Quad Tree", "Use Directional Quad Trees as directional distribution", 1),
    ('VMM', "VMM", "Use von Mises-Fisher models as directional distribution", 2),
)

enum_guiding_directional_sampling_types = (
    ('MIS',
     "Diffuse Product MIS",
     "Guided diffuse BSDF component based on the incoming light distribution and the cosine product (closed form product)",
     0),
    ('RIS',
     "Re-sampled Importance Sampling",
     "Perform RIS sampling to guided based on the product of the incoming light distribution and the BSDF",
     1),
    ('ROUGHNESS',
     "Roughness-based",
     "Adjust the guiding probability based on the roughness of the material components",
     2),
)


def enum_openimagedenoise_denoiser(self, context):
    import _cycles
    if _cycles.with_openimagedenoise:
        return [('OPENIMAGEDENOISE', "OpenImageDenoise",
                 n_("Use Intel OpenImageDenoise AI denoiser"), 4)]
    return []


def enum_optix_denoiser(self, context):
    if not context or bool(context.preferences.addons[__package__].preferences.get_devices_for_type('OPTIX')):
        return [('OPTIX', "OptiX", n_(
            "Use the OptiX AI denoiser with GPU acceleration, only available on NVIDIA GPUs when configured in the system tab in the user preferences"), 2)]
    return []


def enum_preview_denoiser(self, context):
    optix_items = enum_optix_denoiser(self, context)
    oidn_items = enum_openimagedenoise_denoiser(self, context)

    if len(optix_items) or len(oidn_items):
        items = [
            ('AUTO',
             "Automatic",
             n_("Use GPU accelerated denoising if supported, for the best performance. "
                "Prefer OpenImageDenoise over OptiX"),
             0)]
    else:
        items = [('AUTO', "None", n_("Blender was compiled without a viewport denoiser"), 0)]

    items += optix_items
    items += oidn_items
    return items


def enum_denoiser(self, context):
    items = []
    items += enum_optix_denoiser(self, context)
    items += enum_openimagedenoise_denoiser(self, context)
    return items


enum_denoising_input_passes = (
    ('RGB', "None", "Don't use utility passes for denoising", 1),
    ('RGB_ALBEDO', "Albedo", "Use albedo pass for denoising", 2),
    ('RGB_ALBEDO_NORMAL', "Albedo and Normal", "Use albedo and normal passes for denoising", 3),
)

enum_denoising_prefilter = (
    ('NONE',
     "None",
     "No prefiltering, use when guiding passes are noise-free",
     1),
    ('FAST',
     "Fast",
     "Denoise color and guiding passes together. Improves quality when guiding passes are noisy using least amount of extra processing time",
     2),
    ('ACCURATE',
     "Accurate",
     "Prefilter noisy guiding passes before denoising color. Improves quality when guiding passes are noisy using extra processing time",
     3),
)

enum_denoising_quality = (
    ('HIGH',
     "High",
     "High quality",
     1),
    ('BALANCED',
     "Balanced",
     "Balanced between performance and quality",
     2),
    ('FAST',
     "Fast",
     "High performance",
     3),
)

enum_direct_light_sampling_type = (
    ('MULTIPLE_IMPORTANCE_SAMPLING',
     "Multiple Importance Sampling",
     "Multiple importance sampling is used to combine direct light contributions from next-event estimation and forward path tracing",
     0),
    ('FORWARD_PATH_TRACING',
     "Forward Path Tracing",
     "Direct light contributions are only sampled using forward path tracing",
     1),
    ('NEXT_EVENT_ESTIMATION',
     "Next-Event Estimation",
     "Direct light contributions are only sampled using next-event estimation",
     2),
)


def update_render_passes(self, context):
    view_layer = context.view_layer
    view_layer.update_render_passes()


def update_render_engine(self, context):
    scene = context.scene
    scene.update_render_engine()


def update_world(self, context):
    # Force a depsgraph update, because add-on properties don't.
    # (at least not from the UI, see #138071)
    context.scene.world.update_tag()


def update_pause(self, context):
    context.area.tag_redraw()


class CyclesRenderSettings(bpy.types.PropertyGroup):
    __slots__ = ()

    device: EnumProperty(
        name="Device",
        description="Device to use for rendering",
        items=enum_devices,
        default='CPU',
        update=update_render_passes,
    )
    shading_system: BoolProperty(
        name="Open Shading Language",
        description="Use Open Shading Language",
    )

    preview_pause: BoolProperty(
        name="Pause Preview",
        description="Pause all viewport preview renders",
        default=False,
        update=update_pause,
    )

    use_denoising: BoolProperty(
        name="Use Denoising",
        description="Denoise the rendered image",
        default=True,
        update=update_render_passes,
    )
    denoiser: EnumProperty(
        name="Denoiser",
        description="Denoise the image with the selected denoiser. "
        "For denoising the image after rendering",
        items=enum_denoiser,
        default=4,  # Use integer to avoid error in builds without OpenImageDenoise.
        update=update_render_passes,
    )
    denoising_prefilter: EnumProperty(
        name="Denoising Prefilter",
        description="Prefilter noisy guiding (albedo and normal) passes to improve denoising quality when using OpenImageDenoise",
        items=enum_denoising_prefilter,
        default='ACCURATE',
    )
    denoising_quality: EnumProperty(
        name="Denoising Quality",
        description="Overall denoising quality when using OpenImageDenoise",
        items=enum_denoising_quality,
        default='HIGH',
    )
    denoising_input_passes: EnumProperty(
        name="Denoising Input Passes",
        description="Passes used by the denoiser to distinguish noise from shader and geometry detail",
        items=enum_denoising_input_passes,
        default='RGB_ALBEDO_NORMAL',
    )
    denoising_use_gpu: BoolProperty(
        name="Denoise on GPU",
        description="Perform denoising on GPU devices configured in the system tab in the user preferences. This is significantly faster than on CPU, but requires additional GPU memory. When large scenes need more GPU memory, this option can be disabled",
        default=False,
    )

    use_preview_denoising: BoolProperty(
        name="Use Viewport Denoising",
        description="Denoise the image in the 3D viewport",
        default=False,
    )
    preview_denoiser: EnumProperty(
        name="Viewport Denoiser",
        description="Denoise the image after each preview update with the selected denoiser",
        items=enum_preview_denoiser,
        default=0,
    )
    preview_denoising_prefilter: EnumProperty(
        name="Viewport Denoising Prefilter",
        description="Prefilter noisy guiding (albedo and normal) passes to improve denoising quality when using OpenImageDenoise",
        items=enum_denoising_prefilter,
        default='FAST',
    )
    preview_denoising_quality: EnumProperty(
        name="Viewport Denoising Quality",
        description="Overall denoising quality when using OpenImageDenoise",
        items=enum_denoising_quality,
        default='BALANCED',
    )
    preview_denoising_input_passes: EnumProperty(
        name="Viewport Denoising Input Passes",
        description="Passes used by the denoiser to distinguish noise from shader and geometry detail",
        items=enum_denoising_input_passes,
        default='RGB_ALBEDO',
    )
    preview_denoising_start_sample: IntProperty(
        name="Start Denoising",
        description="Sample to start denoising the preview at",
        min=0, max=(1 << 24),
        default=1,
    )
    preview_denoising_use_gpu: BoolProperty(
        name="Denoise Preview on GPU",
        description="Perform denoising on GPU devices configured in the system tab in the user preferences. This is significantly faster than on CPU, but requires additional GPU memory. When large scenes need more GPU memory, this option can be disabled",
        default=True,
    )

    samples: IntProperty(
        name="Samples",
        description="Number of samples to render for each pixel",
        min=1, max=(1 << 24),
        default=4096,
    )
    preview_samples: IntProperty(
        name="Viewport Samples",
        description="Number of samples to render in the viewport, unlimited if 0",
        min=0,
        soft_min=1,
        max=(1 << 24),
        default=1024,
    )

    use_sample_subset: BoolProperty(
        name="Use Sample Subset",
        description="Render a subset of the specified max samples. Typically used for distributed rendering across multiple devices",
        default=False,
    )

    sample_offset: IntProperty(
        name="Sample Subset Offset",
        description="0-based index of sample to start rendering from",
        min=0, max=(1 << 24),
        default=0,
    )

    sample_subset_length: IntProperty(
        name="Sample Subset Length",
        description="The number of samples to render in this subset",
        min=1, max=(1 << 24),
        default=2048,
    )

    time_limit: FloatProperty(
        name="Time Limit",
        description="Limit the render time (excluding synchronization time). "
        "Zero disables the limit",
        min=0.0,
        default=0.0,
        step=100.0,
        unit='TIME_ABSOLUTE',
    )

    sampling_pattern: EnumProperty(
        name="Sampling Pattern",
        description="Random sampling pattern used by the integrator",
        items=enum_sampling_pattern,
        default=5,
    )

    scrambling_distance: FloatProperty(
        name="Scrambling Distance",
        default=1.0,
        min=0.0,
        soft_max=1.0,
        description="Reduce randomization between pixels to improve GPU rendering performance, at the cost of possible rendering artifacts if set too low",
    )
    preview_scrambling_distance: BoolProperty(
        name="Scrambling Distance viewport",
        default=False,
        description="Uses the Scrambling Distance value for the viewport. Faster but may flicker",
    )

    auto_scrambling_distance: BoolProperty(
        name="Automatic Scrambling Distance",
        default=False,
        description="Automatically reduce the randomization between pixels to improve GPU rendering performance, at the cost of possible rendering artifacts",
    )

    use_layer_samples: EnumProperty(
        name="Layer Samples",
        description="How to use per view layer sample settings",
        items=enum_use_layer_samples,
        default='USE',
    )

    light_sampling_threshold: FloatProperty(
        name="Light Sampling Threshold",
        description="Probabilistically terminate light samples when the light contribution is below this threshold (more noise but faster rendering). "
        "Zero disables the test and never ignores lights",
        min=0.0,
        max=1.0,
        default=0.01,
    )

    use_adaptive_sampling: BoolProperty(
        name="Use Adaptive Sampling",
        description="Automatically reduce the number of samples per pixel based on estimated noise level",
        default=True,
    )
    adaptive_threshold: FloatProperty(
        name="Adaptive Sampling Threshold",
        description="Noise level step to stop sampling at, lower values reduce noise at the cost of render time. Zero for automatic setting based on number of AA samples",
        min=0.0,
        max=1.0,
        soft_min=0.001,
        default=0.01,
        precision=4,
    )
    adaptive_min_samples: IntProperty(
        name="Adaptive Min Samples",
        description="Minimum AA samples for adaptive sampling, to discover noisy features before stopping sampling. Zero for automatic setting based on noise threshold",
        min=0,
        max=4096,
        default=0,
    )

    use_preview_adaptive_sampling: BoolProperty(
        name="Use Adaptive Sampling",
        description="Automatically reduce the number of samples per pixel based on estimated noise level, for viewport renders",
        default=True,
    )
    preview_adaptive_threshold: FloatProperty(
        name="Adaptive Sampling Threshold",
        description="Noise level step to stop sampling at, lower values reduce noise at the cost of render time. Zero for automatic setting based on number of AA samples, for viewport renders",
        min=0.0,
        max=1.0,
        soft_min=0.001,
        default=0.1,
        precision=4,
    )
    preview_adaptive_min_samples: IntProperty(
        name="Adaptive Min Samples",
        description="Minimum AA samples for adaptive sampling, to discover noisy features before stopping sampling. Zero for automatic setting based on noise threshold, for viewport renders",
        min=0,
        max=4096,
        default=0,
    )

    direct_light_sampling_type: EnumProperty(
        name="Direct Light Sampling",
        description="The type of strategy used for sampling direct light contributions",
        items=enum_direct_light_sampling_type,
        default='MULTIPLE_IMPORTANCE_SAMPLING',
    )

    use_light_tree: BoolProperty(
        name="Light Tree",
        description="Sample multiple lights more efficiently based on estimated contribution at every shading point",
        default=True,
    )

    min_light_bounces: IntProperty(
        name="Min Light Bounces",
        description="Minimum number of light bounces. Setting this higher reduces noise in the first bounces, "
        "but can also be less efficient for more complex geometry like curves and volumes",
        min=0, max=1024,
        default=0,
    )
    min_transparent_bounces: IntProperty(
        name="Min Transparent Bounces",
        description="Minimum number of transparent bounces. Setting this higher reduces noise in the first bounces, "
        "but can also be less efficient for more complex geometry like curves and volumes",
        min=0, max=1024,
        default=0,
    )

    caustics_reflective: BoolProperty(
        name="Reflective Caustics",
        description="Use reflective caustics, resulting in a brighter image (more noise but added realism)",
        default=True,
    )

    caustics_refractive: BoolProperty(
        name="Refractive Caustics",
        description="Use refractive caustics, resulting in a brighter image (more noise but added realism)",
        default=True,
    )

    blur_glossy: FloatProperty(
        name="Filter Glossy",
        description="Adaptively blur glossy shaders after blurry bounces, "
        "to reduce noise at the cost of accuracy",
        min=0.0, max=10.0,
        default=1.0,
    )

    use_guiding: BoolProperty(
        name="Guiding",
        description="Use path guiding for sampling paths. Path guiding incrementally "
        "learns the light distribution of the scene and guides path into directions "
        "with high direct and indirect light contributions",
        default=False,
    )

    use_deterministic_guiding: BoolProperty(
        name="Deterministic",
        description="Makes path guiding deterministic which means renderings will be "
        "reproducible with the same pixel values every time. This feature slows down "
        "training",
        default=True,
    )

    guiding_distribution_type: EnumProperty(
        name="Guiding Distribution Type",
        description="Type of representation for the guiding distribution",
        items=enum_guiding_distribution,
        default='PARALLAX_AWARE_VMM',
    )

    guiding_directional_sampling_type: EnumProperty(
        name="Directional Sampling Type",
        description="Type of the directional sampling used for guiding",
        items=enum_guiding_directional_sampling_types,
        default='RIS',
    )

    use_surface_guiding: BoolProperty(
        name="Surface Guiding",
        description="Use guiding when sampling directions on a surface",
        default=True,
    )

    surface_guiding_probability: FloatProperty(
        name="Surface Guiding Probability",
        description="The probability of guiding a direction on a surface",
        min=0.0, max=1.0,
        default=0.5,
    )

    use_volume_guiding: BoolProperty(
        name="Volume Guiding",
        description="Use guiding when sampling directions inside a volume",
        default=True,
    )

    guiding_training_samples: IntProperty(
        name="Training Samples",
        description="The maximum number of samples used for training path guiding. "
        "Higher samples lead to more accurate guiding, however may also unnecessarily slow "
        "down rendering once guiding is accurate enough. "
        "A value of 0 will continue training until the last sample",
        min=0,
        soft_min=1,
        default=128,
    )

    volume_guiding_probability: FloatProperty(
        name="Volume Guiding Probability",
        description="The probability of guiding a direction inside a volume",
        min=0.0, max=1.0,
        default=0.5,
    )

    use_guiding_direct_light: BoolProperty(
        name="Guide Direct Light",
        description="Consider the contribution of directly visible light sources during guiding",
        default=True,
    )

    use_guiding_mis_weights: BoolProperty(
        name="Use MIS Weights",
        description="Use the MIS weight to weight the contribution of directly visible light sources during guiding",
        default=True,
    )

    guiding_roughness_threshold: FloatProperty(
        name="Guiding Roughness Threshold",
        description="The minimal roughness value of a material to apply guiding",
        min=0.0, max=1.0,
        default=0.05,
    )

    max_bounces: IntProperty(
        name="Max Bounces",
        description="Total maximum number of bounces",
        min=0, max=1024,
        default=12,
    )

    diffuse_bounces: IntProperty(
        name="Diffuse Bounces",
        description="Maximum number of diffuse reflection bounces, bounded by total maximum",
        min=0, max=1024,
        default=4,
    )
    glossy_bounces: IntProperty(
        name="Glossy Bounces",
        description="Maximum number of glossy reflection bounces, bounded by total maximum",
        min=0, max=1024,
        default=4,
    )
    transmission_bounces: IntProperty(
        name="Transmission Bounces",
        description="Maximum number of transmission bounces, bounded by total maximum",
        min=0, max=1024,
        default=12,
    )
    volume_bounces: IntProperty(
        name="Volume Bounces",
        description="Maximum number of volumetric scattering events",
        min=0, max=1024,
        default=0,
    )

    transparent_max_bounces: IntProperty(
        name="Transparent Max Bounces",
        description="Maximum number of transparent bounces. This is independent of maximum number of other bounces",
        min=0, max=1024,
        default=8,
    )

    volume_step_rate: FloatProperty(
        name="Step Rate",
        description="Globally adjust detail for volume rendering, on top of automatically estimated step size. "
                    "Higher values reduce render time, lower values render with more detail",
        default=1.0,
        min=0.01, max=100.0, soft_min=0.1, soft_max=10.0, precision=2
    )
    volume_preview_step_rate: FloatProperty(
        name="Step Rate",
        description="Globally adjust detail for volume rendering, on top of automatically estimated step size. "
                    "Higher values reduce render time, lower values render with more detail",
        default=1.0,
        min=0.01, max=100.0, soft_min=0.1, soft_max=10.0, precision=2
    )
    volume_max_steps: IntProperty(
        name="Max Steps",
        description="Maximum number of steps through the volume before giving up, "
        "to avoid extremely long render times with big objects or small step sizes",
        default=1024,
        min=2, max=65536
    )

    volume_biased: BoolProperty(
        name="Biased",
        description="Default volume rendering uses null scattering, which is unbiased and has less artifacts, "
        "but could be noisier. Biased option uses ray marching, with controls for steps size and max steps",
        default=False,
    )

    dicing_rate: FloatProperty(
        name="Dicing Rate",
        description="Multiplier for per object adaptive subdivision size",
        min=0.1, max=1000.0, soft_min=0.5,
        default=1.0,
    )
    preview_dicing_rate: FloatProperty(
        name="Viewport Dicing Rate",
        description="Multiplier for per object adaptive subdivision size in the viewport",
        min=0.1, max=1000.0, soft_min=0.5,
        default=8.0,
    )

    max_subdivisions: IntProperty(
        name="Max Subdivisions",
        description="Stop subdividing when this level is reached even if the dicing rate would produce finer tessellation",
        min=0,
        max=16,
        default=12,
    )

    dicing_camera: PointerProperty(
        name="Dicing Camera",
        description="Camera to use as reference point when subdividing geometry, useful to avoid crawling "
        "artifacts in animations when the scene camera is moving",
        type=bpy.types.Object,
        poll=lambda self, obj: obj.type == 'CAMERA',
    )
    offscreen_dicing_scale: FloatProperty(
        name="Offscreen Dicing Scale",
        description="Multiplier for dicing rate of geometry outside of the camera view. The dicing rate "
        "of objects is gradually increased the further they are outside the camera view. "
        "Lower values provide higher quality reflections and shadows for off screen objects, "
        "while higher values use less memory",
        min=1.0, soft_max=25.0,
        default=4.0,
    )

    film_exposure: FloatProperty(
        name="Exposure",
        description="Image brightness scale",
        min=0.0, soft_max=2**10, max=2**32,
        default=1.0,
    )
    film_transparent_glass: BoolProperty(
        name="Transparent Glass",
        description="Render transmissive surfaces as transparent, for compositing glass over another background",
        default=False,
    )
    film_transparent_roughness: FloatProperty(
        name="Transparent Roughness Threshold",
        description="For transparent transmission, keep surfaces with roughness above the threshold opaque",
        min=0.0, max=1.0,
        default=0.1,
    )

    pixel_filter_type: EnumProperty(
        name="Filter Type",
        description="Pixel filter type",
        items=enum_filter_types,
        default='BLACKMAN_HARRIS',
    )

    filter_width: FloatProperty(
        name="Filter Width",
        description="Pixel filter width",
        min=0.01, max=10.0,
        default=1.5,
        subtype='PIXEL'
    )

    seed: IntProperty(
        name="Seed",
        description="Seed value for integrator to get different noise patterns",
        min=0, max=2147483647,
        default=0,
    )

    use_animated_seed: BoolProperty(
        name="Use Animated Seed",
        description="Use different seed values (and hence noise patterns) at different frames",
        default=False,
    )

    sample_clamp_direct: FloatProperty(
        name="Clamp Direct",
        description="If non-zero, the maximum value for a direct sample, "
        "higher values will be scaled down to avoid too "
        "much noise and slow convergence at the cost of accuracy",
        min=0.0, max=1e8,
        default=0.0,
    )

    sample_clamp_indirect: FloatProperty(
        name="Clamp Indirect",
        description="If non-zero, the maximum value for an indirect sample, "
        "higher values will be scaled down to avoid too "
        "much noise and slow convergence at the cost of accuracy",
        min=0.0, max=1e8,
        default=10.0,
    )

    debug_bvh_type: EnumProperty(
        name="Viewport BVH Type",
        description="Choose between faster updates, or faster render",
        items=enum_bvh_types,
        default='DYNAMIC_BVH',
    )
    debug_use_spatial_splits: BoolProperty(
        name="Use Spatial Splits",
        description="Use BVH spatial splits: longer builder time, faster render",
        default=False,
    )
    debug_use_hair_bvh: BoolProperty(
        name="Use Curves BVH",
        description="Use special type BVH optimized for curves (uses more ram but renders faster)",
        default=True,
    )
    debug_use_compact_bvh: BoolProperty(
        name="Use Compact BVH",
        description="Use compact BVH structure (uses less ram but renders slower)",
        default=False,
    )
    debug_bvh_time_steps: IntProperty(
        name="BVH Time Steps",
        description="Split BVH primitives by this number of time steps to speed up render time in cost of memory",
        default=0,
        min=0, max=16,
    )

    bake_type: EnumProperty(
        name="Bake Type",
        default='COMBINED',
        description="Type of pass to bake",
        items=(
            ('COMBINED', "Combined", "", 0),
            ('AO', "Ambient Occlusion", "", 1),
            ('SHADOW', "Shadow", "", 2),
            ('POSITION', "Position", "", 11),
            ('NORMAL', "Normal", "", 3),
            ('UV', "UV", "", 4),
            ('ROUGHNESS', "Roughness", "", 5),
            ('EMIT', "Emission", "", 6),
            ('ENVIRONMENT', "Environment", "", 7),
            ('DIFFUSE', "Diffuse", "", 8),
            ('GLOSSY', "Glossy", "", 9),
            ('TRANSMISSION', "Transmission", "", 10),
        ),
    )

    use_camera_cull: BoolProperty(
        name="Use Camera Cull",
        description="Allow objects to be culled based on the camera frustum",
        default=False,
    )

    camera_cull_margin: FloatProperty(
        name="Camera Cull Margin",
        description="Margin for the camera space culling",
        default=0.1,
        min=0.0, max=5.0,
        subtype='FACTOR'
    )

    use_distance_cull: BoolProperty(
        name="Use Distance Cull",
        description="Allow objects to be culled based on the distance from camera",
        default=False,
    )

    distance_cull_margin: FloatProperty(
        name="Cull Distance",
        description="Cull objects which are further away from camera than this distance",
        default=50,
        min=0.0,
        unit='LENGTH'
    )

    rolling_shutter_type: EnumProperty(
        name="Shutter Type",
        default='NONE',
        description="Type of rolling shutter effect matching CMOS-based cameras",
        items=(
            ('NONE', "None", "No rolling shutter effect used"),
            ('TOP', "Top-Bottom", "Sensor is being scanned from top to bottom")
            # TODO(seergey): Are there real cameras with different scanning direction?
        ),
    )

    rolling_shutter_duration: FloatProperty(
        name="Rolling Shutter Duration",
        description="Scanline \"exposure\" time for the rolling shutter effect",
        default=0.1,
        min=0.0, max=1.0,
        subtype='FACTOR',
    )

    texture_limit: EnumProperty(
        name="Viewport Texture Limit",
        default='OFF',
        description="Limit texture size used by viewport rendering",
        items=enum_texture_limit
    )

    texture_limit_render: EnumProperty(
        name="Render Texture Limit",
        default='OFF',
        description="Limit texture size used by final rendering",
        items=enum_texture_limit
    )

    use_fast_gi: BoolProperty(
        name="Fast GI Approximation",
        description="Approximate diffuse indirect light with background tinted ambient occlusion. "
                    "This provides fast alternative to full global illumination, for interactive viewport rendering or final renders with reduced quality",
        default=False,
    )

    fast_gi_method: EnumProperty(
        name="Fast GI Method",
        default='REPLACE',
        description="Fast GI approximation method",
        items=enum_fast_gi_method
    )

    ao_bounces: IntProperty(
        name="AO Bounces",
        default=1,
        description="After this number of light bounces, use approximate global illumination. 0 disables this feature",
        min=0, max=1024,
    )

    ao_bounces_render: IntProperty(
        name="AO Bounces Render",
        default=1,
        description="After this number of light bounces, use approximate global illumination. 0 disables this feature",
        min=0, max=1024,
    )

    use_auto_tile: BoolProperty(
        name="Auto Tile",
        description="Deprecated, tiling is always enabled",
        default=True,
    )
    tile_size: IntProperty(
        name="Tile Size",
        default=2048,
        description="Render high resolution images in tiles of this size, to reduce memory usage. Tiles are cached to disk while rendering to save memory",
        min=8,
        max=8192,
    )

    # Various fine-tuning debug flags

    def _devices_update_callback(self, context):
        import _cycles
        scene = context.scene.as_pointer()
        return _cycles.debug_flags_update(scene)

    debug_use_cpu_avx2: BoolProperty(name="AVX2", default=True)
    debug_use_cpu_sse42: BoolProperty(name="SSE42", default=True)
    debug_bvh_layout: EnumProperty(
        name="BVH Layout",
        items=enum_bvh_layouts,
        default='EMBREE',
    )

    adaptive_compile_description = "Compile the Cycles GPU kernel with only the feature set required for the current scene"

    debug_use_cuda_adaptive_compile: BoolProperty(
        name="Adaptive Compile",
        description=adaptive_compile_description,
        default=False)

    debug_use_optix_debug: BoolProperty(
        name="OptiX Module Debug",
        description="Load OptiX module in debug mode: lower logging verbosity level, enable validations, and lower optimization level",
        default=False)

    debug_use_hip_adaptive_compile: BoolProperty(
        name="Adaptive Compile",
        description=adaptive_compile_description,
        default=False)

    debug_use_metal_adaptive_compile: BoolProperty(
        name="Adaptive Compile",
        description=adaptive_compile_description,
        default=False)

    @classmethod
    def register(cls):
        bpy.types.Scene.cycles = PointerProperty(
            name="Cycles Render Settings",
            description="Cycles render settings",
            type=cls,
        )

    @classmethod
    def unregister(cls):
        del bpy.types.Scene.cycles


class CyclesCustomCameraSettings(bpy.types.PropertyGroup):
    __slots__ = ()

    @classmethod
    def register(cls):
        bpy.types.Camera.cycles_custom = PointerProperty(
            name="Cycles Custom Camera Settings",
            description="Parameters for custom (OSL-based) cameras",
            type=cls,
        )

    @classmethod
    def unregister(cls):
        del bpy.types.Camera.cycles_custom


class CyclesMaterialSettings(bpy.types.PropertyGroup):
    __slots__ = ()

    emission_sampling: EnumProperty(
        name="Emission Sampling",
        description="Sampling strategy for emissive surfaces",
        translation_context=i18n_contexts.id_light,
        items=enum_emission_sampling,
        default="AUTO",
    )

    use_bump_map_correction: BoolProperty(
        name="Bump Map Correction",
        description="Apply corrections to solve shadow terminator artifacts caused by bump mapping",
        default=True,
    )
    volume_sampling: EnumProperty(
        name="Volume Sampling",
        description="Sampling method to use for volumes",
        items=enum_volume_sampling,
        default='MULTIPLE_IMPORTANCE',
    )

    volume_interpolation: EnumProperty(
        name="Volume Interpolation",
        description="Interpolation method to use for smoke/fire volumes",
        items=enum_volume_interpolation,
        default='LINEAR',
    )

    volume_step_rate: FloatProperty(
        name="Step Rate",
        description="Scale the distance between volume shader samples when rendering the volume "
                    "(lower values give more accurate and detailed results, but also increased render time)",
        default=1.0,
        min=0.001, max=1000.0, soft_min=0.1, soft_max=10.0, precision=4
    )

    @classmethod
    def register(cls):
        bpy.types.Material.cycles = PointerProperty(
            name="Cycles Material Settings",
            description="Cycles material settings",
            type=cls,
        )

    @classmethod
    def unregister(cls):
        del bpy.types.Material.cycles


class CyclesLightSettings(bpy.types.PropertyGroup):
    __slots__ = ()

    max_bounces: IntProperty(
        name="Max Bounces",
        description="Maximum number of bounces the light will contribute to the render",
        min=0, max=1024,
        default=1024,
    )
    use_multiple_importance_sampling: BoolProperty(
        name="Multiple Importance Sample",
        description="Use multiple importance sampling for the light, "
        "reduces noise for area lights and sharp glossy materials",
        default=True,
    )
    is_portal: BoolProperty(
        name="Is Portal",
        description="Use this area light to guide sampling of the background, "
        "note that this will make the light invisible",
        default=False,
    )
    is_caustics_light: BoolProperty(
        name="Shadow Caustics",
        description="Generate approximate caustics in shadows of refractive surfaces. "
        "Lights, caster and receiver objects must have shadow caustics options set to enable this",
        default=False,
    )

    @classmethod
    def register(cls):
        bpy.types.Light.cycles = PointerProperty(
            name="Cycles Light Settings",
            description="Cycles light settings",
            type=cls,
        )

    @classmethod
    def unregister(cls):
        del bpy.types.Light.cycles


class CyclesWorldSettings(bpy.types.PropertyGroup):
    __slots__ = ()

    is_caustics_light: BoolProperty(
        name="Shadow Caustics",
        description="Generate approximate caustics in shadows of refractive surfaces. "
        "Lights, caster and receiver objects must have shadow caustics options set to enable this",
        default=False,
    )
    sampling_method: EnumProperty(
        name="Sampling Method",
        description="How to sample the background light",
        items=enum_world_mis,
        default='AUTOMATIC',
    )
    sample_map_resolution: IntProperty(
        name="Map Resolution",
        description="Importance map size is resolution x resolution/2; "
        "higher values potentially produce less noise, at the cost of memory and speed",
        min=4, max=8192,
        default=1024,
    )
    max_bounces: IntProperty(
        name="Max Bounces",
        description="Maximum number of bounces the background light will contribute to the render",
        min=0, max=1024,
        default=1024,
    )
    volume_sampling: EnumProperty(
        name="Volume Sampling",
        description="Sampling method to use for volumes",
        items=enum_volume_sampling,
        default='EQUIANGULAR',
    )
    volume_interpolation: EnumProperty(
        name="Volume Interpolation",
        description="Interpolation method to use for volumes",
        items=enum_volume_interpolation,
        default='LINEAR',
    )
    volume_step_size: FloatProperty(
        name="Step Size",
        description="Distance between volume shader samples when rendering the volume "
                    "(lower values give more accurate and detailed results, but also increased render time)",
        default=1.0,
        min=0.0000001, max=100000.0, soft_min=0.1, soft_max=100.0, precision=4
    )

    @classmethod
    def register(cls):
        bpy.types.World.cycles = PointerProperty(
            name="Cycles World Settings",
            description="Cycles world settings",
            type=cls,
        )

    @classmethod
    def unregister(cls):
        del bpy.types.World.cycles


class CyclesVisibilitySettings(bpy.types.PropertyGroup):
    __slots__ = ()

    camera: BoolProperty(
        name="Camera",
        description="World visibility for camera rays",
        default=True,
        update=update_world,
    )
    diffuse: BoolProperty(
        name="Diffuse",
        description="World visibility for diffuse reflection rays",
        default=True,
        update=update_world,
    )
    glossy: BoolProperty(
        name="Glossy",
        description="World visibility for glossy reflection rays",
        default=True,
        update=update_world,
    )
    transmission: BoolProperty(
        name="Transmission",
        description="World visibility for transmission rays",
        default=True,
        update=update_world,
    )
    shadow: BoolProperty(
        name="Shadow",
        description="World visibility for shadow rays",
        default=True,
        update=update_world,
    )
    scatter: BoolProperty(
        name="Volume Scatter",
        description="World visibility for volume scatter rays",
        default=True,
        update=update_world,
    )

    @classmethod
    def register(cls):
        bpy.types.World.cycles_visibility = PointerProperty(
            name="Cycles Visibility Settings",
            description="Cycles visibility settings",
            type=cls,
        )

    @classmethod
    def unregister(cls):
        del bpy.types.World.cycles_visibility


class CyclesMeshSettings(bpy.types.PropertyGroup):
    __slots__ = ()

    @classmethod
    def register(cls):
        bpy.types.Mesh.cycles = PointerProperty(
            name="Cycles Mesh Settings",
            description="Cycles mesh settings",
            type=cls,
        )
        bpy.types.Curve.cycles = PointerProperty(
            name="Cycles Mesh Settings",
            description="Cycles mesh settings",
            type=cls,
        )
        bpy.types.MetaBall.cycles = PointerProperty(
            name="Cycles Mesh Settings",
            description="Cycles mesh settings",
            type=cls,
        )

    @classmethod
    def unregister(cls):
        del bpy.types.Mesh.cycles
        del bpy.types.Curve.cycles
        del bpy.types.MetaBall.cycles


class CyclesObjectSettings(bpy.types.PropertyGroup):
    __slots__ = ()

    use_motion_blur: BoolProperty(
        name="Use Motion Blur",
        description="Use motion blur for this object",
        default=True,
    )

    use_deform_motion: BoolProperty(
        name="Use Deformation Motion",
        description="Use deformation motion blur for this object",
        default=True,
    )

    motion_steps: IntProperty(
        name="Motion Steps",
        description="Control accuracy of motion blur, more steps gives more memory usage (actual number of steps is 2^(steps - 1))",
        min=1,
        max=7,
        default=1,
    )

    use_camera_cull: BoolProperty(
        name="Use Camera Cull",
        description="Allow this object and its duplicators to be culled by camera space culling",
        default=False,
    )

    use_distance_cull: BoolProperty(
        name="Use Distance Cull",
        description="Allow this object and its duplicators to be culled by distance from camera",
        default=False,
    )

    shadow_terminator_offset: FloatProperty(
        name="Shadow Terminator Shading Offset",
        description="Push the shadow terminator towards the light to hide artifacts on low poly geometry",
        min=0.0, max=1.0,
        default=0.0,
    )

    shadow_terminator_geometry_offset: FloatProperty(
        name="Shadow Terminator Geometry Offset",
        description="Offset rays from the surface to reduce shadow terminator artifact on low poly geometry. Only affects triangles at grazing angles to light",
        min=0.0,
        max=1.0,
        default=0.1,
    )

    ao_distance: FloatProperty(
        name="AO Distance",
        description="AO distance used for approximate global illumination (0 means use world setting)",
        min=0.0,
        default=0.0,
        subtype='DISTANCE',
    )

    is_caustics_caster: BoolProperty(
        name="Cast Shadow Caustics",
        description="With refractive materials, generate approximate caustics in shadows of this object. "
        "Up to 10 bounces inside this object are taken into account. Lights, caster and receiver objects "
        "must have shadow caustics options set to enable this",
        default=False,
    )

    is_caustics_receiver: BoolProperty(
        name="Receive Shadow Caustics",
        description="Receive approximate caustics from refractive materials in shadows on this object. "
        "Lights, caster and receiver objects must have shadow caustics options set to enable this",
        default=False,
    )

    @classmethod
    def register(cls):
        bpy.types.Object.cycles = PointerProperty(
            name="Cycles Object Settings",
            description="Cycles object settings",
            type=cls,
        )

    @classmethod
    def unregister(cls):
        del bpy.types.Object.cycles


class CyclesCurveRenderSettings(bpy.types.PropertyGroup):
    __slots__ = ()

    shape: EnumProperty(
        name="Shape",
        description="Form of curves",
        items=enum_curve_shape,
        default='RIBBONS',
    )
    subdivisions: IntProperty(
        name="Subdivisions",
        description="Number of subdivisions used in Cardinal curve intersection (power of 2)",
        min=0, max=24,
        default=2,
    )

    @classmethod
    def register(cls):
        bpy.types.Scene.cycles_curves = PointerProperty(
            name="Cycles Curves Rendering Settings",
            description="Cycles curves rendering settings",
            type=cls,
        )

    @classmethod
    def unregister(cls):
        del bpy.types.Scene.cycles_curves


class CyclesRenderLayerSettings(bpy.types.PropertyGroup):
    __slots__ = ()

    pass_debug_sample_count: BoolProperty(
        name="Debug Sample Count",
        description="Number of samples per pixel taken, divided by the maximum number of samples. To analyze adaptive sampling",
        default=False,
        update=update_render_passes,
    )
    pass_render_time: BoolProperty(
        name="Render Time",
        description="Reports time per pixel in milliseconds. Supported only on CPU render devices",
        default=False,
        update=update_render_passes,
    )
    use_pass_volume_direct: BoolProperty(
        name="Volume Direct",
        description="Deliver direct volumetric scattering pass",
        default=False,
        update=update_render_passes,
    )
    use_pass_volume_indirect: BoolProperty(
        name="Volume Indirect",
        description="Deliver indirect volumetric scattering pass",
        default=False,
        update=update_render_passes,
    )
    use_pass_volume_scatter: BoolProperty(
        name="Volume Scatter",
        description="Contribution of paths that scattered in the volume at the primary ray",
        default=False,
        update=update_render_passes,
    )
    use_pass_volume_transmit: BoolProperty(
        name="Volume Transmit",
        description="Contribution of paths that transmitted through the volume at the primary ray",
        default=False,
        update=update_render_passes,
    )
    use_pass_volume_majorant: BoolProperty(
        name="Volume Majorant",
        description="Majorant transmittance of the volume",
        default=False,
        update=update_render_passes,
    )

    use_pass_shadow_catcher: BoolProperty(
        name="Shadow Catcher",
        description="Pass containing shadows and light which is to be multiplied into backdrop",
        default=False,
        update=update_render_passes,
    )

    use_denoising: BoolProperty(
        name="Use Denoising",
        description="Denoise the rendered image",
        default=True,
        update=update_render_passes,
    )
    denoising_store_passes: BoolProperty(
        name="Store Denoising Passes",
        description="Store the denoising feature passes and the noisy image. The passes adapt to the denoiser selected for rendering",
        default=False,
        update=update_render_passes,
    )

    @classmethod
    def register(cls):
        bpy.types.ViewLayer.cycles = PointerProperty(
            name="Cycles ViewLayer Settings",
            description="Cycles ViewLayer Settings",
            type=cls,
        )

    @classmethod
    def unregister(cls):
        del bpy.types.ViewLayer.cycles


class CyclesDeviceSettings(bpy.types.PropertyGroup):
    # Runtime properties
    __slots__ = ("is_optimized")

    # Properties saved in preferences
    id: StringProperty(name="ID", description="Unique identifier of the device")
    name: StringProperty(name="Name", description="Name of the device")
    use: BoolProperty(name="Use", description="Use device for rendering", default=True)
    type: EnumProperty(name="Type", items=enum_device_type, default='CUDA')


class CyclesPreferences(bpy.types.AddonPreferences):
    bl_idname = __package__

    @staticmethod
    def default_device():
        import platform
        # Default to selecting the Metal compute device on Apple Silicon GPUs
        # (drivers are tightly integrated with macOS so pose no stability risk)
        if (platform.system() == 'Darwin') and (platform.machine() == 'arm64'):
            return 5
        return 0

    def get_device_types(self, context):
        import _cycles
        has_cuda, has_optix, has_hip, has_metal, has_oneapi, has_hiprt = _cycles.get_device_types()

        list = [('NONE', "None", n_("Do not use compute device"), 0)]
        if has_cuda:
            list.append(('CUDA', "CUDA", n_("Use CUDA for GPU acceleration"), 1))
        if has_optix:
            list.append(('OPTIX', "OptiX", n_("Use OptiX for GPU acceleration"), 3))
        if has_hip:
            list.append(('HIP', "HIP", n_("Use HIP for GPU acceleration"), 4))
        if has_metal:
            list.append(('METAL', "Metal", n_("Use Metal for GPU acceleration"), 5))
        if has_oneapi:
            list.append(('ONEAPI', "oneAPI", n_("Use oneAPI for GPU acceleration"), 6))

        return list

    compute_device_type: EnumProperty(
        name="Compute Device Type",
        description="Device to use for computation (rendering with Cycles)",
        default=CyclesPreferences.default_device(),
        items=CyclesPreferences.get_device_types,
    )

    devices: CollectionProperty(type=CyclesDeviceSettings)

    peer_memory: BoolProperty(
        name="Distribute memory across devices",
        description="Make more room for large scenes to fit by distributing memory across interconnected devices (e.g. via NVLink) rather than duplicating it",
        default=False,
    )

    metalrt: EnumProperty(
        name="MetalRT",
        description="MetalRT for ray tracing uses less memory for scenes which use curves extensively, and can give better "
                    "performance in specific cases",
        default='AUTO',
        items=(
            ('OFF', "Off", "Disable MetalRT (uses BVH2 layout for intersection queries)"),
            ('ON', "On", "Enable MetalRT for intersection queries"),
            ('AUTO', "Auto", "Automatically pick the fastest intersection method"),
        ),
    )

    use_hiprt: BoolProperty(
        name="HIP RT",
        description="HIP RT enables AMD hardware ray tracing on RDNA2 and above",
        default=True,
    )

    use_oneapirt: BoolProperty(
        name="Embree on GPU",
        description="Embree on GPU enables the use of hardware ray tracing on Intel GPUs, providing better overall performance",
        default=True,
    )

    kernel_optimization_level: EnumProperty(
        name="Kernel Optimization",
        description="Kernels can be optimized based on scene content. Optimized kernels are requested at the start of a render. "
                    "If optimized kernels are not available, rendering will proceed using generic kernels until the optimized set "
                    "is available in the cache. This can result in additional CPU usage for a brief time (tens of seconds)",
        default='FULL',
        items=(
            ('OFF', "Off", "Disable kernel optimization. Slowest rendering, no extra background CPU usage"),
            ('INTERSECT', "Intersection only", "Optimize only intersection kernels. Faster rendering, negligible extra background CPU usage"),
            ('FULL', "Full", "Optimize all kernels. Fastest rendering, may result in extra background CPU usage"),
        ),
    )

    # Be careful when deciding when to call this function,
    # as Blender can crash with `_cycles.available_devices()` on some drivers.
    def get_device_list(self, compute_device_type):
        import _cycles
        device_list = _cycles.available_devices(compute_device_type)
        # Make sure device entries are up to date and not referenced before
        # we know we won't add new devices. This way we guarantee to not
        # hold pointers to a resized array.
        self.update_device_entries(device_list)
        return device_list

    def find_existing_device_entry(self, device):
        for device_entry in self.devices:
            if device_entry.id == device[2] and device_entry.type == device[1]:
                return device_entry
        return None

    def update_device_entries(self, device_list):
        for device in device_list:
            if not device[1] in {'CUDA', 'OPTIX', 'CPU', 'HIP', 'METAL', 'ONEAPI'}:
                continue
            # Try to find existing Device entry
            entry = self.find_existing_device_entry(device)
            if not entry:
                # Create new entry if no existing one was found
                entry = self.devices.add()
                entry.id = device[2]
                entry.name = device[0]
                entry.type = device[1]
                entry.use = entry.type != 'CPU'
            elif entry.name != device[0]:
                # Update name in case it changed
                entry.name = device[0]

    # Gets all devices types to display in the preferences for a compute device type.
    # This includes the CPU device.
    def get_devices_for_type(self, compute_device_type, device_list=None):
        # Layout of the device tuples: (Name, Type, Persistent ID)
        if device_list is None:
            device_list = self.get_device_list(compute_device_type)

        # Sort entries into lists
        devices = []
        cpu_devices = []
        for device in device_list:
            entry = self.find_existing_device_entry(device)
            entry.is_optimized = device[7]
            if entry.type == compute_device_type:
                devices.append(entry)
            elif entry.type == 'CPU':
                cpu_devices.append(entry)
        # Extend all GPU devices with CPU.
        if len(devices) and compute_device_type != 'CPU':
            devices.extend(cpu_devices)
        return devices

    # Refresh device list. This does not happen automatically on Blender
    # startup due to unstable drivers that can cause crashes.
    def refresh_devices(self):
        # Ensure `self.devices` is not re-allocated when the second call to
        # get_devices_for_type is made, freeing items from the first list.
        for device_type in ('CUDA', 'OPTIX', 'HIP', 'METAL', 'ONEAPI'):
            # Query the device list to trigger all required updates.
            # Note that even though the device list is unused,
            # the function has side-effects with internal state updates.
            _device_list = self.get_device_list(device_type)

    # Deprecated: use refresh_devices instead.
    def get_devices(self, compute_device_type=''):
        self.refresh_devices()
        return None

    def get_compute_device_type(self):
        if self.compute_device_type == '':
            return 'NONE'
        return self.compute_device_type

    def get_num_gpu_devices(self):
        compute_device_type = self.get_compute_device_type()

        num = 0
        if compute_device_type != 'NONE':
            for device in self.get_device_list(compute_device_type):
                if device[1] != compute_device_type:
                    continue
                for dev in self.devices:
                    if dev.use and dev.id == device[2]:
                        num += 1
        return num

    def has_multi_device(self):
        compute_device_type = self.get_compute_device_type()
        if compute_device_type != 'NONE':
            for device in self.get_device_list(compute_device_type):
                if device[1] == compute_device_type:
                    continue
                for dev in self.devices:
                    if dev.use and dev.id == device[2]:
                        return True

        return False

    def has_active_device(self):
        return self.get_num_gpu_devices() > 0

    def has_oidn_gpu_devices(self):
        compute_device_type = self.get_compute_device_type()

        # We need non-CPU devices, used for rendering and supporting OIDN GPU denoising
        if compute_device_type != 'NONE':
            for device in self.get_device_list(compute_device_type):
                device_type = device[1]
                if device_type == 'CPU':
                    continue

                has_device_oidn_support = device[5]
                if has_device_oidn_support and self.find_existing_device_entry(device).use:
                    return True

        return False

    def has_optixdenoiser_gpu_devices(self):
        compute_device_type = self.get_compute_device_type()

        if compute_device_type == 'OPTIX':
            # We need any OptiX devices, used for rendering
            for device in self.get_device_list(compute_device_type):
                device_type = device[1]
                if device_type == 'CPU':
                    continue

                has_device_optixdenoiser_support = device[6]
                if has_device_optixdenoiser_support and self.find_existing_device_entry(device).use:
                    return True

        return False

    @staticmethod
    def _format_device_name(name):
        import unicodedata
        return name.replace('(TM)', unicodedata.lookup('TRADE MARK SIGN')) \
                   .replace('(tm)', unicodedata.lookup('TRADE MARK SIGN')) \
                   .replace('(R)', unicodedata.lookup('REGISTERED SIGN')) \
                   .replace('(C)', unicodedata.lookup('COPYRIGHT SIGN'))

    def _draw_devices(self, layout, device_type, device_list):
        box = layout.box()

        # Get preference devices, including CPU.
        devices = self.get_devices_for_type(device_type, device_list)

        found_device = False
        for device in devices:
            if device.type == device_type:
                found_device = True
                break

        if not found_device:
            col = box.column(align=True)
            col.label(text=rpt_("No compatible GPUs found for Cycles"), icon='INFO', translate=False)

            if device_type == 'CUDA':
                compute_capability = "5.0"
                col.label(text=rpt_("Requires NVIDIA GPU with compute capability %s") % compute_capability,
                          icon='BLANK1', translate=False)
            elif device_type == 'OPTIX':
                compute_capability = "5.0"
                driver_version = "535"
                col.label(text=rpt_("Requires NVIDIA GPU with compute capability %s") % compute_capability,
                          icon='BLANK1', translate=False)
                col.label(text=rpt_("and NVIDIA driver version %s or newer") % driver_version,
                          icon='BLANK1', translate=False)
            elif device_type == 'HIP':
                import sys
                if sys.platform[:3] == "win":
                    adrenalin_driver_version = "24.9.1"
                    pro_driver_version = "24.Q4"
                    col.label(
                        text=rpt_("Requires AMD GPU with RDNA architecture"),
                        icon='BLANK1',
                        translate=False)
                    col.label(text=rpt_("and AMD Adrenalin driver %s or newer") %
                              adrenalin_driver_version, icon='BLANK1', translate=False)
                    col.label(text=rpt_("or AMD Radeon Pro %s driver or newer") %
                              pro_driver_version, icon='BLANK1', translate=False)
                elif sys.platform.startswith("linux"):
                    rocm_version = "6.0"
                    driver_version = "23.40"
                    col.label(
                        text=rpt_("Requires AMD GPU with RDNA architecture"),
                        icon='BLANK1',
                        translate=False)
                    col.label(
                        text=rpt_("and ROCm HIP Runtime %s or newer") %
                        rocm_version, icon='BLANK1', translate=False)
                    col.label(text=rpt_("or AMD driver version %s or newer") %
                              driver_version, icon='BLANK1', translate=False)
            elif device_type == 'ONEAPI':
                import sys
                if sys.platform.startswith("win"):
                    driver_version = "XX.X.101.8306"
                    col.label(text=rpt_("Requires Intel GPU with Xe-HPG architecture"), icon='BLANK1', translate=False)
                    col.label(text=rpt_("and Windows driver version %s or newer") % driver_version,
                              icon='BLANK1', translate=False)
                elif sys.platform.startswith("linux"):
                    driver_version = "XX.XX.34666.3"
                    col.label(
                        text=rpt_("Requires Intel GPU with Xe-HPG architecture and"),
                        icon='BLANK1',
                        translate=False)
                    col.label(
                        text=rpt_("  - intel-level-zero-gpu or intel-compute-runtime version"),
                        icon='BLANK1',
                        translate=False)
                    col.label(text=rpt_("    %s or newer") % driver_version, icon='BLANK1', translate=False)
                    col.label(text=rpt_("  - oneAPI Level-Zero Loader"), icon='BLANK1', translate=False)
            elif device_type == 'METAL':
                mac_version = "12.2"
                col.label(text=rpt_("Requires Apple Silicon with macOS %s or newer") % mac_version,
                          icon='BLANK1', translate=False)
            return

        for device in devices:
            name = self._format_device_name(device.name)
            if not device.is_optimized:
                name += rpt_(" (Unoptimized Performance)")
            box.prop(device, "use", text=name, translate=False)

    def draw_impl(self, layout, context):
        row = layout.row()
        row.prop(self, "compute_device_type", expand=True)

        compute_device_type = self.get_compute_device_type()
        if compute_device_type == 'NONE':
            return
        row = layout.row()
        devices = self.get_device_list(compute_device_type)
        self._draw_devices(row, compute_device_type, devices)

        import _cycles
        has_peer_memory = False
        has_enabled_hardware_rt = False
        has_disabled_hardware_rt = False
        for device in devices:
            if not self.find_existing_device_entry(device).use:
                continue
            if device[1] != compute_device_type:
                continue

            if device[3]:
                has_peer_memory = True
            if device[4]:
                has_enabled_hardware_rt = True
            else:
                has_disabled_hardware_rt = True

        # Any device without RT support will disable it for all.
        has_hardware_rt = has_enabled_hardware_rt and not has_disabled_hardware_rt

        if has_peer_memory:
            row = layout.row()
            row.use_property_split = True
            row.prop(self, "peer_memory")

        if compute_device_type == 'METAL':
            import platform

            # MetalRT only works on Apple Silicon.
            if (platform.machine() == 'arm64'):
                col = layout.column()
                col.use_property_split = True
                col.prop(self, "kernel_optimization_level")
                row = col.row()
                row.active = has_hardware_rt
                row.prop(self, "metalrt")

        if compute_device_type == 'HIP':
            row = layout.row()
            row.active = has_hardware_rt
            row.prop(self, "use_hiprt")

        elif compute_device_type == 'ONEAPI' and _cycles.with_embree_gpu:
            row = layout.row()
            row.active = has_hardware_rt
            row.prop(self, "use_oneapirt")

    def draw(self, context):
        self.draw_impl(self.layout, context)


class CyclesView3DShadingSettings(bpy.types.PropertyGroup):
    __slots__ = ()

    prefs = bpy.context.preferences
    use_debug = prefs.experimental.use_cycles_debug and prefs.view.show_developer_ui

    render_pass: EnumProperty(
        name="Render Pass",
        description="Render pass to show in the 3D Viewport",
        items=enum_view3d_shading_render_pass +
        enum_view3d_debug_render_pass if use_debug else enum_view3d_shading_render_pass,
        default='COMBINED',
    )
    show_active_pixels: BoolProperty(
        name="Show Active Pixels",
        description="When using adaptive sampling highlight pixels which are being sampled",
    )


def register():
    bpy.utils.register_class(CyclesRenderSettings)
    bpy.utils.register_class(CyclesCustomCameraSettings)
    bpy.utils.register_class(CyclesMaterialSettings)
    bpy.utils.register_class(CyclesLightSettings)
    bpy.utils.register_class(CyclesWorldSettings)
    bpy.utils.register_class(CyclesVisibilitySettings)
    bpy.utils.register_class(CyclesMeshSettings)
    bpy.utils.register_class(CyclesObjectSettings)
    bpy.utils.register_class(CyclesCurveRenderSettings)
    bpy.utils.register_class(CyclesDeviceSettings)
    bpy.utils.register_class(CyclesPreferences)
    bpy.utils.register_class(CyclesRenderLayerSettings)
    bpy.utils.register_class(CyclesView3DShadingSettings)

    bpy.types.View3DShading.cycles = bpy.props.PointerProperty(
        name="Cycles Settings",
        type=CyclesView3DShadingSettings,
    )


def unregister():
    bpy.utils.unregister_class(CyclesRenderSettings)
    bpy.utils.unregister_class(CyclesCustomCameraSettings)
    bpy.utils.unregister_class(CyclesMaterialSettings)
    bpy.utils.unregister_class(CyclesLightSettings)
    bpy.utils.unregister_class(CyclesWorldSettings)
    bpy.utils.unregister_class(CyclesMeshSettings)
    bpy.utils.unregister_class(CyclesObjectSettings)
    bpy.utils.unregister_class(CyclesVisibilitySettings)
    bpy.utils.unregister_class(CyclesCurveRenderSettings)
    bpy.utils.unregister_class(CyclesDeviceSettings)
    bpy.utils.unregister_class(CyclesPreferences)
    bpy.utils.unregister_class(CyclesRenderLayerSettings)
    bpy.utils.unregister_class(CyclesView3DShadingSettings)
