shading_properties.py

# SPDX-License-Identifier: GPL-2.0-or-later

# <pep8 compliant>
"""Declare shading properties exported to POV textures."""
import bpy
from bpy.utils import register_class, unregister_class
from bpy.types import PropertyGroup
from bpy.props import (
    FloatVectorProperty,
    StringProperty,
    BoolProperty,
    IntProperty,
    FloatProperty,
    EnumProperty,
    PointerProperty,
)


def check_material(mat):
    """Check that material node tree is not empty if use node button is on"""
    if mat is not None:
        if mat.use_nodes:
            # No active node material
            return not mat.node_tree
        return True
    return False


def pov_context_tex_datablock(context):
    """Texture context type recreated as deprecated in blender 2.8"""

    idblock = context.brush
    if idblock and context.scene.texture_context == 'OTHER':
        return idblock

    # idblock = bpy.context.active_object.active_material
    idblock = context.view_layer.objects.active.active_material
    if idblock and context.scene.texture_context == 'MATERIAL':
        return idblock

    idblock = context.scene.world
    if idblock and context.scene.texture_context == 'WORLD':
        return idblock

    idblock = context.light
    if idblock and context.scene.texture_context == 'LIGHT':
        return idblock

    if context.particle_system and context.scene.texture_context == 'PARTICLES':
        idblock = context.particle_system.settings


    idblock = context.line_style
    if idblock and context.scene.texture_context == 'LINESTYLE':
        return idblock

    return idblock


def active_texture_name_from_uilist(self, context):
    """Name created texture slots the same as created texture"""
    idblock = pov_context_tex_datablock(context)
    # mat = context.view_layer.objects.active.active_material
    if idblock is not None:
        index = idblock.pov.active_texture_index
        name = idblock.pov_texture_slots[index].name
        newname = idblock.pov_texture_slots[index].texture
        tex = bpy.data.textures[name]
        tex.name = newname
        idblock.pov_texture_slots[index].name = newname


def active_texture_name_from_search(self, context):
    """Texture rolldown to change the data linked by an existing texture"""
    idblock = pov_context_tex_datablock(context)
    # mat = context.view_layer.objects.active.active_material
    if idblock is not None:
        index = idblock.pov.active_texture_index
        slot = idblock.pov_texture_slots[index]
        name = slot.texture_search

    try:
        # tex = bpy.data.textures[name]
        slot.name = name
        slot.texture = name
        # Switch paint brush to this texture so settings remain contextual
        # bpy.context.tool_settings.image_paint.brush.texture = tex
        # bpy.context.tool_settings.image_paint.brush.mask_texture = tex
    except BaseException as e:
        print(e.__doc__)
        print('An exception occurred: {}'.format(e))


def brush_texture_update(self, context):

    """Brush texture rolldown must show active slot texture props"""
    idblock = pov_context_tex_datablock(context)
    if idblock is not None:
        # mat = context.view_layer.objects.active.active_material
        idblock = pov_context_tex_datablock(context)
        slot = idblock.pov_texture_slots[idblock.pov.active_texture_index]
        tex = slot.texture

        if tex:
            # Switch paint brush to active texture so slot and settings remain contextual
            bpy.context.tool_settings.image_paint.brush.texture = bpy.data.textures[tex]
            bpy.context.tool_settings.image_paint.brush.mask_texture = bpy.data.textures[tex]


class RenderPovSettingsMaterial(PropertyGroup):
    """Declare material level properties controllable in UI and translated to POV."""

    # --------------------------- Begin Old Blender Internal Props --------------------------- #
    # former Space properties from  removed Blender Internal
    use_limited_texture_context: BoolProperty(
        name="",
        description="Use the limited version of texture user (for ‘old shading’ mode)",
        default=True,
    )
    texture_context: EnumProperty(
        name="Texture context",
        description="Type of texture data to display and edit",
        items=(
            ("MATERIAL", "", "Show material textures", "MATERIAL", 0),  # "Show material textures"
            ("WORLD", "", "Show world textures", "WORLD", 1),  # "Show world textures"
            ("LAMP", "", "Show lamp textures", "LIGHT", 2),  # "Show lamp textures"
            (
                "PARTICLES",
                "",
                "Show particles textures",
                "PARTICLES",
                3,
            ),  # "Show particles textures"
            (
                "LINESTYLE",
                "",
                "Show linestyle textures",
                "LINE_DATA",
                4,
            ),  # "Show linestyle textures"
            (
                "OTHER",
                "",
                "Show other data textures",
                "TEXTURE_DATA",
                5,
            ),  # "Show other data textures"
        ),
        default="MATERIAL",
    )

    active_texture_index: IntProperty(
        name="Index for texture_slots", default=0, update=brush_texture_update
    )

    transparency_method: EnumProperty(
        name="Specular Shader Model",
        description="Method to use for rendering transparency",
        items=(
            ("MASK", "Mask", "Mask the background"),
            ("Z_TRANSPARENCY", "Z Transparency", "Use alpha buffer for transparent faces"),
            ("RAYTRACE", "Raytrace", "Use raytracing for transparent refraction rendering"),
        ),
        default="MASK",
    )

    use_transparency: BoolProperty(
        name="Transparency", description="Render material as transparent", default=False
    )

    alpha: FloatProperty(
        name="Alpha",
        description="Alpha transparency of the material",
        min=0.0,
        max=1.0,
        soft_min=0.0,
        soft_max=1.0,
        default=1.0,
        precision=3,
    )

    specular_alpha: FloatProperty(
        name="Specular alpha",
        description="Alpha transparency for specular areas",
        min=0.0,
        max=1.0,
        soft_min=0.0,
        soft_max=1.0,
        default=1.0,
        precision=3,
    )

    ambient: FloatProperty(
        name="Ambient",
        description="Amount of global ambient color the material receives",
        min=0.0,
        max=1.0,
        soft_min=0.0,
        soft_max=1.0,
        default=1.0,