blender-addons/render_povray/shading.py
Campbell Barton 016430de4b Cleanup: remove <pep8 compliant> comment
This is no longer necessary, see: T98554.
2022-06-03 11:50:32 +10:00

426 lines
20 KiB
Python
Executable File

# SPDX-License-Identifier: GPL-2.0-or-later
"""Translate complex shaders to exported POV textures."""
import bpy
def write_object_material_interior(file, material, ob, tab_write):
"""Translate some object level material from Blender UI (VS data level)
to POV interior{} syntax and write it to exported file.
This is called in model_all.objects_loop
"""
# DH - modified some variables to be function local, avoiding RNA write
# this should be checked to see if it is functionally correct
# Commented out: always write IOR to be able to use it for SSS, Fresnel reflections...
# if material and material.pov.transparency_method == 'RAYTRACE':
if not material:
return
# implicit if material:
# But there can be only one ior!
if material.pov_subsurface_scattering.use: # SSS IOR get highest priority
tab_write(file, "interior {\n")
tab_write(file, "ior %.6f\n" % material.pov_subsurface_scattering.ior)
# Then the raytrace IOR taken from raytrace transparency properties and used for
# reflections if IOR Mirror option is checked.
elif material.pov.mirror_use_IOR or material.pov.transparency_method != "Z_TRANSPARENCY":
tab_write(file, "interior {\n")
tab_write(file, "ior %.6f\n" % material.pov_raytrace_transparency.ior)
else:
tab_write(file, "interior {\n")
tab_write(file, "ior 1.0\n")
pov_fake_caustics = False
pov_photons_refraction = False
pov_photons_reflection = bool(material.pov.photons_reflection)
if not material.pov.refraction_caustics:
pov_fake_caustics = False
pov_photons_refraction = False
elif material.pov.refraction_type == "1":
pov_fake_caustics = True
pov_photons_refraction = False
elif material.pov.refraction_type == "2":
pov_fake_caustics = False
pov_photons_refraction = True
# If only Raytrace transparency is set, its IOR will be used for refraction, but user
# can set up 'un-physical' fresnel reflections in raytrace mirror parameters.
# Last, if none of the above is specified, user can set up 'un-physical' fresnel
# reflections in raytrace mirror parameters. And pov IOR defaults to 1.
if material.pov.caustics_enable:
if pov_fake_caustics:
tab_write(file, "caustics %.3g\n" % material.pov.fake_caustics_power)
if pov_photons_refraction:
# Default of 1 means no dispersion
tab_write(file, "dispersion %.6f\n" % material.pov.photons_dispersion)
tab_write(file, "dispersion_samples %.d\n" % material.pov.photons_dispersion_samples)
# TODO
# Other interior args
if material.pov.use_transparency and material.pov.transparency_method == "RAYTRACE":
# fade_distance
# In Blender this value has always been reversed compared to what tooltip says.
# 100.001 rather than 100 so that it does not get to 0
# which deactivates the feature in POV
tab_write(
file, "fade_distance %.3g\n" % (100.001 - material.pov_raytrace_transparency.depth_max)
)
# fade_power
tab_write(file, "fade_power %.3g\n" % material.pov_raytrace_transparency.falloff)
# fade_color
tab_write(file, "fade_color <%.3g, %.3g, %.3g>\n" % material.pov.interior_fade_color[:])
# (variable) dispersion_samples (constant count for now)
tab_write(file, "}\n")
if material.pov.photons_reflection or material.pov.refraction_type == "2":
tab_write(file, "photons{")
tab_write(file, "target %.3g\n" % ob.pov.spacing_multiplier)
if not ob.pov.collect_photons:
tab_write(file, "collect off\n")
if pov_photons_refraction:
tab_write(file, "refraction on\n")
if pov_photons_reflection:
tab_write(file, "reflection on\n")
tab_write(file, "}\n")
def write_material(
file,
using_uberpov,
DEF_MAT_NAME,
tab_write,
comments,
unique_name,
material_names_dictionary,
material,
):
"""Translate Blender material to POV texture{} block and write in exported file."""
# Assumes only called once on each material
from .render import safety
if material:
name_orig = material.name
name = material_names_dictionary[name_orig] = unique_name(
bpy.path.clean_name(name_orig), material_names_dictionary
)
# If saturation(.s) is not zero, then color is not grey, and has a tint
colored_specular_found = (material.pov.specular_color.s > 0.0) and (
material.pov.diffuse_shader != "MINNAERT"
)
else:
name = name_orig = DEF_MAT_NAME
##################
# Several versions of the finish: ref_level_bound conditions are variations for specular/Mirror
# texture channel map with alternative finish of 0 specular and no mirror reflection.
# ref_level_bound=1 Means No specular nor Mirror reflection
# ref_level_bound=2 Means translation of spec and mir levels for when no map influences them
# ref_level_bound=3 Means Maximum Spec and Mirror
def pov_has_no_specular_maps(file, ref_level_bound):
"""Translate Blender specular map influence to POV finish map trick and write to file."""
if ref_level_bound == 1:
if comments:
tab_write(file, "//--No specular nor Mirror reflection--\n")
else:
tab_write(file, "\n")
tab_write(file, "#declare %s = finish {\n" % safety(name, ref_level_bound=1))
elif ref_level_bound == 2:
if comments:
tab_write(
file,
"//--translation of spec and mir levels for when no map " "influences them--\n",
)
else:
tab_write(file, "\n")
tab_write(file, "#declare %s = finish {\n" % safety(name, ref_level_bound=2))
elif ref_level_bound == 3:
if comments:
tab_write(file, "//--Maximum Spec and Mirror--\n")
else:
tab_write(file, "\n")
tab_write(file, "#declare %s = finish {\n" % safety(name, ref_level_bound=3))
if material:
# POV-Ray 3.7 now uses two diffuse values respectively for front and back shading
# (the back diffuse is like blender translucency)
front_diffuse = material.pov.diffuse_intensity
back_diffuse = material.pov.translucency
if material.pov.conserve_energy:
# Total should not go above one
if (front_diffuse + back_diffuse) <= 1.0:
pass
elif front_diffuse == back_diffuse:
# Try to respect the user's 'intention' by comparing the two values but
# bringing the total back to one.
front_diffuse = back_diffuse = 0.5
# Let the highest value stay the highest value.
elif front_diffuse > back_diffuse:
# clamps the sum below 1
back_diffuse = min(back_diffuse, (1.0 - front_diffuse))
else:
front_diffuse = min(front_diffuse, (1.0 - back_diffuse))
# map hardness between 0.0 and 1.0
roughness = 1.0 - ((material.pov.specular_hardness - 1.0) / 510.0)
## scale from 0.0 to 0.1
roughness *= 0.1
# add a small value because 0.0 is invalid.
roughness += 1.0 / 511.0
# ------------------------------ Diffuse Shader ------------------------------ #
# Not used for Full spec (ref_level_bound=3) of the shader.
if material.pov.diffuse_shader == "OREN_NAYAR" and ref_level_bound != 3:
# Blender roughness is what is generally called oren nayar Sigma,
# and brilliance in POV-Ray.
tab_write(file, "brilliance %.3g\n" % (0.9 + material.roughness))
if material.pov.diffuse_shader == "TOON" and ref_level_bound != 3:
tab_write(file, "brilliance %.3g\n" % (0.01 + material.diffuse_toon_smooth * 0.25))
# Lower diffuse and increase specular for toon effect seems to look better
# in POV-Ray.
front_diffuse *= 0.5
if material.pov.diffuse_shader == "MINNAERT" and ref_level_bound != 3:
# tab_write(file, "aoi %.3g\n" % material.pov.darkness)
pass # let's keep things simple for now
if material.pov.diffuse_shader == "FRESNEL" and ref_level_bound != 3:
# tab_write(file, "aoi %.3g\n" % material.pov.diffuse_fresnel_factor)
pass # let's keep things simple for now
if material.pov.diffuse_shader == "LAMBERT" and ref_level_bound != 3:
# trying to best match lambert attenuation by that constant brilliance value
tab_write(file, "brilliance 1\n")
if ref_level_bound == 2:
# ------------------------------ Specular Shader ------------------------------ #
# No difference between phong and cook torrence in blender HaHa!
if material.pov.specular_shader in ["COOKTORR", "PHONG"]:
tab_write(file, "phong %.3g\n" % material.pov.specular_intensity)
tab_write(file, "phong_size %.3g\n" % (material.pov.specular_hardness / 3.14))
# POV-Ray 'specular' keyword corresponds to a Blinn model, without the ior.
elif material.pov.specular_shader == "BLINN":
# Use blender Blinn's IOR just as some factor for spec intensity
tab_write(
file,
"specular %.3g\n"
% (material.pov.specular_intensity * (material.pov.specular_ior / 4.0)),
)
tab_write(file, "roughness %.3g\n" % roughness)
# Could use brilliance 2(or varying around 2 depending on ior or factor) too.
elif material.pov.specular_shader == "TOON":
tab_write(file, "phong %.3g\n" % (material.pov.specular_intensity * 2.0))
# use extreme phong_size
tab_write(
file, "phong_size %.3g\n" % (0.1 + material.pov.specular_toon_smooth / 2.0)
)
elif material.pov.specular_shader == "WARDISO":
# find best suited default constant for brilliance Use both phong and
# specular for some values.
tab_write(
file,
"specular %.3g\n"
% (
material.pov.specular_intensity / (material.pov.specular_slope + 0.0005)
),
)
# find best suited default constant for brilliance Use both phong and
# specular for some values.
tab_write(
file, "roughness %.4g\n" % (0.0005 + material.pov.specular_slope / 10.0)
)
# find best suited default constant for brilliance Use both phong and
# specular for some values.
tab_write(file, "brilliance %.4g\n" % (1.8 - material.pov.specular_slope * 1.8))
# -------------------------------------------------------------------------------- #
elif ref_level_bound == 1:
if material.pov.specular_shader in ["COOKTORR", "PHONG"]:
tab_write(file, "phong 0\n") # %.3g\n" % (material.pov.specular_intensity/5))
tab_write(file, "phong_size %.3g\n" % (material.pov.specular_hardness / 3.14))
# POV-Ray 'specular' keyword corresponds to a Blinn model, without the ior.
elif material.pov.specular_shader == "BLINN":
# Use blender Blinn's IOR just as some factor for spec intensity
tab_write(
file,
"specular %.3g\n"
% (material.pov.specular_intensity * (material.pov.specular_ior / 4.0)),
)
tab_write(file, "roughness %.3g\n" % roughness)
# Could use brilliance 2(or varying around 2 depending on ior or factor) too.
elif material.pov.specular_shader == "TOON":
tab_write(file, "phong %.3g\n" % (material.pov.specular_intensity * 2.0))
# use extreme phong_size
tab_write(
file, "phong_size %.3g\n" % (0.1 + material.pov.specular_toon_smooth / 2.0)
)
elif material.pov.specular_shader == "WARDISO":
# find best suited default constant for brilliance Use both phong and
# specular for some values.
tab_write(
file,
"specular %.3g\n"
% (
material.pov.specular_intensity / (material.pov.specular_slope + 0.0005)
),
)
# find best suited default constant for brilliance Use both phong and
# specular for some values.
tab_write(
file, "roughness %.4g\n" % (0.0005 + material.pov.specular_slope / 10.0)
)
# find best suited default constant for brilliance Use both phong and
# specular for some values.
tab_write(file, "brilliance %.4g\n" % (1.8 - material.pov.specular_slope * 1.8))
elif ref_level_bound == 3:
# Spec must be Max at ref_level_bound 3 so that white of mixing texture always shows specularity
# That's why it's multiplied by 255. maybe replace by texture's brightest pixel value?
if material.pov_texture_slots:
max_spec_factor = (
material.pov.specular_intensity
* material.pov.specular_color.v
* 255
* slot.specular_factor
)
else:
max_spec_factor = (
material.pov.specular_intensity * material.pov.specular_color.v * 255
)
tab_write(file, "specular %.3g\n" % max_spec_factor)
tab_write(file, "roughness %.3g\n" % (1 / material.pov.specular_hardness))
tab_write(file, "diffuse %.3g, %.3g\n" % (front_diffuse, back_diffuse))
tab_write(file, "ambient %.3g\n" % material.pov.ambient)
# POV-Ray blends the global value
# tab_write(file, "ambient rgb <%.3g, %.3g, %.3g>\n" % \
# tuple([c*material.pov.ambient for c in world.ambient_color]))
tab_write(file, "emission %.3g\n" % material.pov.emit) # New in POV-Ray 3.7
# POV-Ray just ignores roughness if there's no specular keyword
# tab_write(file, "roughness %.3g\n" % roughness)
if material.pov.conserve_energy:
# added for more realistic shading. Needs some checking to see if it
# really works. --Maurice.
tab_write(file, "conserve_energy\n")
if colored_specular_found:
tab_write(file, "metallic\n")
# 'phong 70.0 '
if ref_level_bound != 1 and material.pov_raytrace_mirror.use:
raytrace_mirror = material.pov_raytrace_mirror
if raytrace_mirror.reflect_factor:
tab_write(file, "reflection {\n")
tab_write(file, "rgb <%.3g, %.3g, %.3g>\n" % material.pov.mirror_color[:])
if material.metallic:
tab_write(file, "metallic %.3g\n" % material.metallic)
# Blurry reflections for UberPOV
if using_uberpov and raytrace_mirror.gloss_factor < 1.0:
# tab_write(file, "#ifdef(unofficial) #if(unofficial = \"patch\") #if(patch(\"upov-reflection-roughness\") > 0)\n")
tab_write(
file, "roughness %.6f\n" % (0.000001 / raytrace_mirror.gloss_factor)
)
# tab_write(file, "#end #end #end\n") # This and previous comment for backward compatibility, messier pov code
if material.pov.mirror_use_IOR: # WORKING ?
# Removed from the line below: gives a more physically correct
# material but needs proper IOR. --Maurice
tab_write(file, "fresnel 1 ")
tab_write(
file,
"falloff %.3g exponent %.3g} "
% (raytrace_mirror.fresnel, raytrace_mirror.fresnel_factor),
)
if material.pov_subsurface_scattering.use:
subsurface_scattering = material.pov_subsurface_scattering
tab_write(
file,
"subsurface { translucency <%.3g, %.3g, %.3g> }\n"
% (
(subsurface_scattering.radius[0]),
(subsurface_scattering.radius[1]),
(subsurface_scattering.radius[2]),
),
)
if material.pov.irid_enable:
tab_write(
file,
"irid { %.4g thickness %.4g turbulence %.4g }"
% (
material.pov.irid_amount,
material.pov.irid_thickness,
material.pov.irid_turbulence,
),
)
else:
tab_write(file, "diffuse 0.8\n")
tab_write(file, "phong 70.0\n")
# tab_write(file, "specular 0.2\n")
# This is written into the object
"""
if material and material.pov.transparency_method=='RAYTRACE':
'interior { ior %.3g} ' % material.raytrace_transparency.ior
"""
# tab_write(file, "crand 1.0\n") # Sand granyness
# tab_write(file, "metallic %.6f\n" % material.metallic)
# tab_write(file, "phong %.6f\n" % material.spec)
# tab_write(file, "phong_size %.6f\n" % material.spec)
# tab_write(file, "brilliance %.6f " % (material.pov.specular_hardness/256.0) # Like hardness
tab_write(file, "}\n\n")
# ref_level_bound=2 Means translation of spec and mir levels for when no map influences them
pov_has_no_specular_maps(file, ref_level_bound=2)
if material:
special_texture_found = False
tmpidx = -1
slot = None
for t in material.pov_texture_slots:
tmpidx += 1
# index = material.pov.active_texture_index
slot = material.pov_texture_slots[tmpidx] # [index]
povtex = slot.texture # slot.name
tex = bpy.data.textures[povtex]
if t and t.use and tex is not None:
if (tex.type == "IMAGE" and tex.image) or tex.type != "IMAGE":
# validPath
if (
t
and t.use
and (
t.use_map_specular
or t.use_map_raymir
or t.use_map_normal
or t.use_map_alpha
)
):
special_texture_found = True
continue # Some texture found
if special_texture_found or colored_specular_found:
# ref_level_bound=1 Means No specular nor Mirror reflection
pov_has_no_specular_maps(file, ref_level_bound=1)
# ref_level_bound=3 Means Maximum Spec and Mirror
pov_has_no_specular_maps(file, ref_level_bound=3)