render.py

# ***** BEGIN GPL LICENSE BLOCK *****
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# #**** END GPL LICENSE BLOCK #****

# <pep8 compliant>

import bpy
import subprocess
import os
import sys
import time
from math import atan, pi, degrees, sqrt, cos, sin
import re
import random
import platform#
import subprocess#
import tempfile #generate temporary files with random names
from bpy.types import(Operator)
from imghdr import what #imghdr is a python lib to identify image file types
from bpy.utils import register_class

from . import df3 # for smoke rendering
from . import shading # for BI POV shaders emulation
from . import primitives # for import and export of POV specific primitives
from . import nodes # for POV specific nodes
##############################SF###########################
##############find image texture
def imageFormat(imgF):
    """Identify input image filetypes to transmit to POV."""
    # First use the below explicit extensions to identify image file prospects
    ext = {
        'JPG': "jpeg",
        'JPEG': "jpeg",
        'GIF': "gif",
        'TGA': "tga",
        'IFF': "iff",
        'PPM': "ppm",
        'PNG': "png",
        'SYS': "sys",
        'TIFF': "tiff",
        'TIF': "tiff",
        'EXR': "exr",
        'HDR': "hdr",
    }.get(os.path.splitext(imgF)[-1].upper(), "")
    # Then, use imghdr to really identify the filetype as it can be different
    if not ext:
        #maybe add a check for if path exists here?
        print(" WARNING: texture image has no extension") #too verbose

        ext = what(imgF) #imghdr is a python lib to identify image file types
    return ext


def imgMap(ts):
    """Translate mapping type from Blender UI to POV syntax and return that string."""
    image_map = ""
    if ts.mapping == 'FLAT':
        image_map = "map_type 0 "
    elif ts.mapping == 'SPHERE':
        image_map = "map_type 1 "
    elif ts.mapping == 'TUBE':
        image_map = "map_type 2 "

    ## map_type 3 and 4 in development (?) (ENV in pov 3.8)
    ## for POV-Ray, currently they just seem to default back to Flat (type 0)
    #elif ts.mapping=="?":
    #    image_map = " map_type 3 "
    #elif ts.mapping=="?":
    #    image_map = " map_type 4 "
    if ts.texture.use_interpolation:
        image_map += " interpolate 2 "
    if ts.texture.extension == 'CLIP':
        image_map += " once "
    #image_map += "}"
    #if ts.mapping=='CUBE':
    #    image_map+= "warp { cubic } rotate <-90,0,180>"
    # no direct cube type mapping. Though this should work in POV 3.7
    # it doesn't give that good results(best suited to environment maps?)
    #if image_map == "":
    #    print(" No texture image  found ")
    return image_map


def imgMapTransforms(ts):
    """Translate mapping transformations from Blender UI to POV syntax and return that string."""
    # XXX TODO: unchecked textures give error of variable referenced before assignment XXX
    # POV-Ray "scale" is not a number of repetitions factor, but ,its
    # inverse, a standard scale factor.
    # 0.5 Offset is needed relatively to scale because center of the
    # scale is 0.5,0.5 in blender and 0,0 in POV
            # Strange that the translation factor for scale is not the same as for
            # translate.
            # TODO: verify both matches with blender internal.
    image_map_transforms = ""
    image_map_transforms = ("scale <%.4g,%.4g,%.4g> translate <%.4g,%.4g,%.4g>" % \
                  ( 1.0 / ts.scale.x,
                  1.0 / ts.scale.y,
                  1.0 / ts.scale.z,
                  0.5-(0.5/ts.scale.x) - (ts.offset.x),
                  0.5-(0.5/ts.scale.y) - (ts.offset.y),
                  ts.offset.z))
    # image_map_transforms = (" translate <-0.5,-0.5,0.0> scale <%.4g,%.4g,%.4g> translate <%.4g,%.4g,%.4g>" % \
                  # ( 1.0 / ts.scale.x,
                  # 1.0 / ts.scale.y,
                  # 1.0 / ts.scale.z,
                  # (0.5 / ts.scale.x) + ts.offset.x,
                  # (0.5 / ts.scale.y) + ts.offset.y,
                  # ts.offset.z))
    # image_map_transforms = ("translate <-0.5,-0.5,0> scale <-1,-1,1> * <%.4g,%.4g,%.4g> translate <0.5,0.5,0> + <%.4g,%.4g,%.4g>" % \
                  # (1.0 / ts.scale.x,
                  # 1.0 / ts.scale.y,
                  # 1.0 / ts.scale.z,
                  # ts.offset.x,
                  # ts.offset.y,
                  # ts.offset.z))
    return image_map_transforms

def imgMapBG(wts):
    """Translate world mapping from Blender UI to POV syntax and return that string."""
    image_mapBG = ""
    # texture_coords refers to the mapping of world textures:
    if wts.texture_coords == 'VIEW' or wts.texture_coords == 'GLOBAL':
        image_mapBG = " map_type 0 "
    elif wts.texture_coords == 'ANGMAP':
        image_mapBG = " map_type 1 "
    elif wts.texture_coords == 'TUBE':
        image_mapBG = " map_type 2 "

    if wts.texture.use_interpolation:
        image_mapBG += " interpolate 2 "
    if wts.texture.extension == 'CLIP':
        image_mapBG += " once "
    #image_mapBG += "}"
    #if wts.mapping == 'CUBE':
    #   image_mapBG += "warp { cubic } rotate <-90,0,180>"
    # no direct cube type mapping. Though this should work in POV 3.7
    # it doesn't give that good results(best suited to environment maps?)
    #if image_mapBG == "":
    #    print(" No background texture image  found ")
    return image_mapBG


def path_image(image):
    """Conform a path string to POV syntax to avoid POV errors."""
    return bpy.path.abspath(image.filepath, library=image.library).replace("\\","/")
    # .replace("\\","/") to get only forward slashes as it's what POV prefers,
    # even on windows
# end find image texture
# -----------------------------------------------------------------------------


def string_strip_hyphen(name):
    """Remove hyphen characters from a string to avoid POV errors."""
    return name.replace("-", "")


def safety(name, Level):
    """append suffix characters to names of various material declinations.

    Material declinations are necessary to POV syntax and used in shading.py
    by the povHasnoSpecularMaps function to create the finish map trick and
    the suffixes avoid name collisions.
    Keyword arguments:
    name -- the initial material name as a string
    Level -- the enum number of the Level being written:
        Level=1 is for texture with No specular nor Mirror reflection
        Level=2 is for texture with translation of spec and mir levels
        for when no map influences them
        Level=3 is for texture with Maximum Spec and Mirror
    """

    try:
        if int(name) > 0:
            prefix = "shader"
    except:
        prefix = ""
    prefix = "shader_"
    name = string_strip_hyphen(name)
    if Level == 2:
        return prefix + name
    elif Level == 1:
        return prefix + name + "0"  # used for 0 of specular map
    elif Level == 3:
        return prefix + name + "1"  # used for 1 of specular map


##############end safety string name material
##############################EndSF###########################

csg_list = []

def is_renderable(scene, ob):
    return (not ob.hide_render and ob not in csg_list)


def renderable_objects(scene):
    return [ob for ob in bpy.data.objects if is_renderable(scene, ob)]

def no_renderable_objects(scene):
    return [ob for ob in csg_list]

tabLevel = 0
unpacked_images=[]

user_dir = bpy.utils.resource_path('USER')
preview_dir = os.path.join(user_dir, "preview")

## Make sure Preview directory exists and is empty
smokePath = os.path.join(preview_dir, "smoke.df3")
'''
def write_global_setting(scene,file):
    file.write("global_settings {\n")
    file.write("    assumed_gamma %.6f\n"%scene.pov.assumed_gamma)
    if scene.pov.global_settings_advanced:
        if scene.pov.radio_enable == False:
            file.write("    adc_bailout %.6f\n"%scene.pov.adc_bailout)
        file.write("    ambient_light <%.6f,%.6f,%.6f>\n"%scene.pov.ambient_light[:])
        file.write("    irid_wavelength <%.6f,%.6f,%.6f>\n"%scene.pov.irid_wavelength[:])
        file.write("    charset %s\n"%scene.pov.charset)
        file.write("    max_trace_level %s\n"%scene.pov.max_trace_level)
        file.write("    max_intersections %s\n"%scene.pov.max_intersections)
        file.write("    number_of_waves %s\n"%scene.pov.number_of_waves)
        file.write("    noise_generator %s\n"%scene.pov.noise_generator)

    # below properties not added to __init__ yet to avoid conflicts with material sss scale
    # unless it would override then should be interfaced also in scene units property tab

    # if scene.pov.sslt_enable:
        # file.write("    mm_per_unit %s\n"%scene.pov.mm_per_unit)
        # file.write("    subsurface {\n")
        # file.write("        samples %s, %s\n"%(scene.pov.sslt_samples_max,scene.pov.sslt_samples_min))
        # if scene.pov.sslt_radiosity:
            # file.write("        radiosity on\n")
        # file.write("}\n")

    if scene.pov.radio_enable:
        file.write("    radiosity {\n")
        file.write("        pretrace_start %.6f\n"%scene.pov.radio_pretrace_start)
        file.write("        pretrace_end %.6f\n"%scene.pov.radio_pretrace_end)
        file.write("        count %s\n"%scene.pov.radio_count)
        file.write("        nearest_count %s\n"%scene.pov.radio_nearest_count)
        file.write("        error_bound %.6f\n"%scene.pov.radio_error_bound)
        file.write("        recursion_limit %s\n"%scene.pov.radio_recursion_limit)
        file.write("        low_error_factor %.6f\n"%scene.pov.radio_low_error_factor)
        file.write("        gray_threshold %.6f\n"%scene.pov.radio_gray_threshold)
        file.write("        maximum_reuse %.6f\n"%scene.pov.radio_maximum_reuse)
        file.write("        minimum_reuse %.6f\n"%scene.pov.radio_minimum_reuse)
        file.write("        brightness %.6f\n"%scene.pov.radio_brightness)
        file.write("        adc_bailout %.6f\n"%scene.pov.radio_adc_bailout)
        if scene.pov.radio_normal:
            file.write("        normal on\n")
        if scene.pov.radio_always_sample:
            file.write("        always_sample on\n")
        if scene.pov.radio_media:
            file.write("        media on\n")
        if scene.pov.radio_subsurface:
            file.write("        subsurface on\n")
        file.write("    }\n")

    if scene.pov.photon_enable:
        file.write("    photons {\n")
        if scene.pov.photon_enable_count:
            file.write("        count %s\n"%scene.pov.photon_count)
        else:
            file.write("        spacing %.6g\n"%scene.pov.photon_spacing)
        if scene.pov.photon_gather:
            file.write("        gather %s, %s\n"%(scene.pov.photon_gather_min,scene.pov.photon_gather_max))
        if scene.pov.photon_autostop:
            file.write("        autostop %.4g\n"%scene.pov.photon_autostop_value)
        if scene.pov.photon_jitter_enable:
            file.write("        jitter %.4g\n"%scene.pov.photon_jitter)
        file.write("        max_trace_level %s\n"%scene.pov.photon_max_trace_level)
        if scene.pov.photon_adc:
            file.write("        adc_bailout %.6f\n"%scene.pov.photon_adc_bailout)
        if scene.pov.photon_media_enable:
            file.write("        media %s, %s\n"%(scene.pov.photon_media_steps,scene.pov.photon_media_factor))
        if scene.pov.photon_map_file_save_load in {'save'}:
            filePhName = 'Photon_map_file.ph'
            if scene.pov.photon_map_file != '':
                filePhName = scene.pov.photon_map_file+'.ph'
            filePhDir = tempfile.gettempdir()
            path = bpy.path.abspath(scene.pov.photon_map_dir)
            if os.path.exists(path):
                filePhDir = path
            fullFileName = os.path.join(filePhDir,filePhName)
            file.write('        save_file "%s"\n'%fullFileName)
            scene.pov.photon_map_file = fullFileName
        if scene.pov.photon_map_file_save_load in {'load'}:
            fullFileName = bpy.path.abspath(scene.pov.photon_map_file)
            if os.path.exists(fullFileName):
                file.write('        load_file "%s"\n'%fullFileName)
        file.write("}\n")
    file.write("}\n")
'''
def write_object_modifiers(scene,ob,File):
    """Translate some object level POV statements from Blender UI
    to POV syntax and write to exported file """

    # Maybe return that string to be added instead of directly written.

    '''XXX WIP
    onceCSG = 0
    for mod in ob.modifiers:
        if onceCSG == 0:
            if mod :
                if mod.type == 'BOOLEAN':
                    if ob.pov.boolean_mod == "POV":
                        File.write("\tinside_vector <%.6g, %.6g, %.6g>\n" %
                                   (ob.pov.inside_vector[0],
                                    ob.pov.inside_vector[1],
                                    ob.pov.inside_vector[2]))
                        onceCSG = 1
    '''

    if ob.pov.hollow:
        File.write("\thollow\n")
    if ob.pov.double_illuminate:
        File.write("\tdouble_illuminate\n")
    if ob.pov.sturm:
        File.write("\tsturm\n")
    if ob.pov.no_shadow:
        File.write("\tno_shadow\n")
    if ob.pov.no_image:
        File.write("\tno_image\n")
    if ob.pov.no_reflection:
        File.write("\tno_reflection\n")
    if ob.pov.no_radiosity:
        File.write("\tno_radiosity\n")
    if ob.pov.inverse:
        File.write("\tinverse\n")
    if ob.pov.hierarchy:
        File.write("\thierarchy\n")

    # XXX, Commented definitions
    '''
    if scene.pov.photon_enable:
        File.write("photons {\n")
        if ob.pov.target:
            File.write("target %.4g\n"%ob.pov.target_value)
        if ob.pov.refraction:
            File.write("refraction on\n")
        if ob.pov.reflection:
            File.write("reflection on\n")
        if ob.pov.pass_through:
            File.write("pass_through\n")
        File.write("}\n")
    if ob.pov.object_ior > 1:
        File.write("interior {\n")
        File.write("ior %.4g\n"%ob.pov.object_ior)
        if scene.pov.photon_enable and ob.pov.target and ob.pov.refraction and ob.pov.dispersion:
            File.write("ior %.4g\n"%ob.pov.dispersion_value)
            File.write("ior %s\n"%ob.pov.dispersion_samples)
        if scene.pov.photon_enable == False:
            File.write("caustics %.4g\n"%ob.pov.fake_caustics_power)
    '''



def write_pov(filename, scene=None, info_callback=None):
    """Main export process from Blender UI to POV syntax and write to exported file """
    import mathutils
    #file = filename
    file = open(filename, "w")

    # Only for testing
    if not scene:
        scene = bpy.data.scenes[0]

    render = scene.render
    world = scene.world
    global_matrix = mathutils.Matrix.Rotation(-pi / 2.0, 4, 'X')
    comments = scene.pov.comments_enable and not scene.pov.tempfiles_enable
    linebreaksinlists = scene.pov.list_lf_enable and not scene.pov.tempfiles_enable
    feature_set = bpy.context.preferences.addons[__package__].preferences.branch_feature_set_povray
    using_uberpov = (feature_set=='uberpov')
    pov_binary = PovrayRender._locate_binary()

    if using_uberpov:
        print("Unofficial UberPOV feature set chosen in preferences")
    else:
        print("Official POV-Ray 3.7 feature set chosen in preferences")
    if 'uber' in pov_binary:
        print("The name of the binary suggests you are probably rendering with Uber POV engine")
    else:
        print("The name of the binary suggests you are probably rendering with standard POV engine")
    def setTab(tabtype, spaces):
        TabStr = ""
        if tabtype == 'NONE':
            TabStr = ""
        elif tabtype == 'TAB':
            TabStr = "\t"
        elif tabtype == 'SPACE':
            TabStr = spaces * " "
        return TabStr

    tab = setTab(scene.pov.indentation_character, scene.pov.indentation_spaces)
    if not scene.pov.tempfiles_enable:
        def tabWrite(str_o):
            """Indent POV syntax from brackets levels and write to exported file """
            global tabLevel
            brackets = str_o.count("{") - str_o.count("}") + str_o.count("[") - str_o.count("]")
            if brackets < 0:
                tabLevel = tabLevel + brackets
            if tabLevel < 0:
                print("Indentation Warning: tabLevel = %s" % tabLevel)
                tabLevel = 0
            if tabLevel >= 1:
                file.write("%s" % tab * tabLevel)
            file.write(str_o)
            if brackets > 0:
                tabLevel = tabLevel + brackets
    else:
        def tabWrite(str_o):
            """write directly to exported file if user checked autonamed temp files (faster)."""

            file.write(str_o)

    def uniqueName(name, nameSeq):
        """Increment any generated POV name that could get identical to avoid collisions"""

        if name not in nameSeq:
            name = string_strip_hyphen(name)
            return name

        name_orig = name
        i = 1
        while name in nameSeq:
            name = "%s_%.3d" % (name_orig, i)
            i += 1
        name = string_strip_hyphen(name)
        return name

    def writeMatrix(matrix):
        """Translate some tranform matrix from Blender UI
        to POV syntax and write to exported file """
        tabWrite("matrix <%.6f, %.6f, %.6f,  %.6f, %.6f, %.6f,  %.6f, %.6f, %.6f,  %.6f, %.6f, %.6f>\n" %
                 (matrix[0][0], matrix[1][0], matrix[2][0],
                  matrix[0][1], matrix[1][1], matrix[2][1],
                  matrix[0][2], matrix[1][2], matrix[2][2],
                  matrix[0][3], matrix[1][3], matrix[2][3]))

    def MatrixAsPovString(matrix):
        """Translate some tranform matrix from Blender UI
        to POV syntax and return that string """
        sMatrix = ("matrix <%.6f, %.6f, %.6f,  %.6f, %.6f, %.6f,  %.6f, %.6f, %.6f,  %.6f, %.6f, %.6f>\n" %
                   (matrix[0][0], matrix[1][0], matrix[2][0],
                    matrix[0][1], matrix[1][1], matrix[2][1],
                    matrix[0][2], matrix[1][2], matrix[2][2],
                    matrix[0][3], matrix[1][3], matrix[2][3]))
        return sMatrix

    def writeObjectMaterial(material, ob):
        """Translate some object level material from Blender UI (VS data level)
        to POV interior{} syntax and write it to exported file """

        # 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.transparency_method == 'RAYTRACE':
        if material:
            # But there can be only one!
            if material.pov_subsurface_scattering.use:  # SSS IOR get highest priority
                tabWrite("interior {\n")
                tabWrite("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:
                tabWrite("interior {\n")
                tabWrite("ior %.6f\n" % material.pov_raytrace_transparency.ior)
            elif material.pov.transparency_method=='Z_TRANSPARENCY':
                tabWrite("interior {\n")
                tabWrite("ior 1.0\n")
            else:
                tabWrite("interior {\n")
                tabWrite("ior %.6f\n" % material.pov_raytrace_transparency.ior)

            pov_fake_caustics = False
            pov_photons_refraction = False
            pov_photons_reflection = False

            if material.pov.photons_reflection:
                pov_photons_reflection = True
            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:
                    tabWrite("caustics %.3g\n" % material.pov.fake_caustics_power)
                if pov_photons_refraction:
                    # Default of 1 means no dispersion
                    tabWrite("dispersion %.6f\n" % material.pov.photons_dispersion)
                    tabWrite("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
                tabWrite("fade_distance %.3g\n" % \
                         (100.001 - material.pov_raytrace_transparency.depth_max))
                # fade_power
                tabWrite("fade_power %.3g\n" % material.pov_raytrace_transparency.falloff)
                # fade_color
                tabWrite("fade_color <%.3g, %.3g, %.3g>\n" % material.pov.interior_fade_color[:])

            # (variable) dispersion_samples (constant count for now)
            tabWrite("}\n")
            if material.pov.photons_reflection or material.pov.refraction_type=="2":
                tabWrite("photons{")
                tabWrite("target %.3g\n" % ob.pov.spacing_multiplier)
                if not ob.pov.collect_photons:
                    tabWrite("collect off\n")
                if pov_photons_refraction:
                    tabWrite("refraction on\n")
                if pov_photons_reflection:
                    tabWrite("reflection on\n")
                tabWrite("}\n")

    materialNames = {}
    DEF_MAT_NAME = "" #or "Default"?

    def exportCamera():
        """Translate camera from Blender UI to POV syntax and write to exported file."""
        camera = scene.camera

        # DH disabled for now, this isn't the correct context
        active_object = None  # bpy.context.active_object # does not always work  MR
        matrix = global_matrix @ camera.matrix_world
        focal_point = camera.data.dof.focus_distance

        # compute resolution
        Qsize = render.resolution_x / render.resolution_y
        tabWrite("#declare camLocation  = <%.6f, %.6f, %.6f>;\n" %
                 matrix.translation[:])
        tabWrite("#declare camLookAt = <%.6f, %.6f, %.6f>;\n" %
                 tuple([degrees(e) for e in matrix.to_3x3().to_euler()]))

        tabWrite("camera {\n")
        if scene.pov.baking_enable and active_object and active_object.type == 'MESH':
            tabWrite("mesh_camera{ 1 3\n")  # distribution 3 is what we want here
            tabWrite("mesh{%s}\n" % active_object.name)
            tabWrite("}\n")
            tabWrite("location <0,0,.01>")
            tabWrite("direction <0,0,-1>")
        # Using standard camera otherwise
        else:
            tabWrite("location  <0, 0, 0>\n")
            tabWrite("look_at  <0, 0, -1>\n")
            tabWrite("right <%s, 0, 0>\n" % - Qsize)
            tabWrite("up <0, 1, 0>\n")
            tabWrite("angle  %f\n" % (360.0 * atan(16.0 / camera.data.lens) / pi))

            tabWrite("rotate  <%.6f, %.6f, %.6f>\n" % \
                     tuple([degrees(e) for e in matrix.to_3x3().to_euler()]))
            tabWrite("translate <%.6f, %.6f, %.6f>\n" % matrix.translation[:])
            if camera.data.dof.use_dof and (focal_point != 0 or camera.data.dof.focus_object):
                tabWrite("aperture %.3g\n" % (1/camera.data.dof.aperture_fstop*1000))
                tabWrite("blur_samples %d %d\n" % \
                         (camera.data.pov.dof_samples_min, camera.data.pov.dof_samples_max))
                tabWrite("variance 1/%d\n" % camera.data.pov.dof_variance)
                tabWrite("confidence %.3g\n" % camera.data.pov.dof_confidence)
                if camera.data.dof.focus_object:
                    focalOb = scene.objects[camera.data.dof.focus_object.name]
                    matrixBlur = global_matrix @ focalOb.matrix_world
                    tabWrite("focal_point <%.4f,%.4f,%.4f>\n"% matrixBlur.translation[:])
                else:
                    tabWrite("focal_point <0, 0, %f>\n" % focal_point)
        if camera.data.pov.normal_enable:
            tabWrite("normal {%s %.4f turbulence %.4f scale %.4f}\n"%
                    (camera.data.pov.normal_patterns,
                    camera.data.pov.cam_normal,
                    camera.data.pov.turbulence,
                    camera.data.pov.scale))
        tabWrite("}\n")



    def exportLamps(lamps):
        """Translate lights from Blender UI to POV syntax and write to exported file."""
        # Incremented after each lamp export to declare its target
        # currently used for Fresnel diffuse shader as their slope vector:
        global lampCount
        lampCount = 0
        # Get all lamps
        for ob in lamps:
            lamp = ob.data

            matrix = global_matrix @ ob.matrix_world

            # Color is no longer modified by energy
            color = tuple([c for c in lamp.color])

            tabWrite("light_source {\n")
            tabWrite("< 0,0,0 >\n")
            tabWrite("color srgb<%.3g, %.3g, %.3g>\n" % color)

            if lamp.type == 'POINT':
                pass
            elif lamp.type == 'SPOT':
                tabWrite("spotlight\n")

                # Falloff is the main radius from the centre line
                tabWrite("falloff %.2f\n" % (degrees(lamp.spot_size) / 2.0))  # 1 TO 179 FOR BOTH
                tabWrite("radius %.6f\n" % \
                         ((degrees(lamp.spot_size) / 2.0) * (1.0 - lamp.spot_blend)))

                # Blender does not have a tightness equivalent, 0 is most like blender default.
                tabWrite("tightness 0\n")  # 0:10f

                tabWrite("point_at  <0, 0, -1>\n")
                if lamp.pov.use_halo:
                    tabWrite("looks_like{\n")
                    tabWrite("sphere{<0,0,0>,%.6f\n" %lamp.distance)
                    tabWrite("hollow\n")
                    tabWrite("material{\n")
                    tabWrite("texture{\n")
                    tabWrite("pigment{rgbf<1,1,1,%.4f>}\n" % (lamp.pov.halo_intensity*5.0))
                    tabWrite("}\n")
                    tabWrite("interior{\n")
                    tabWrite("media{\n")
                    tabWrite("emission 1\n")
                    tabWrite("scattering {1, 0.5}\n")
                    tabWrite("density{\n")
                    tabWrite("spherical\n")
                    tabWrite("color_map{\n")
                    tabWrite("[0.0 rgb <0,0,0>]\n")
                    tabWrite("[0.5 rgb <1,1,1>]\n")
                    tabWrite("[1.0 rgb <1,1,1>]\n")
                    tabWrite("}\n")
                    tabWrite("}\n")
                    tabWrite("}\n")
                    tabWrite("}\n")
                    tabWrite("}\n")
                    tabWrite("}\n")
                    tabWrite("}\n")
            elif lamp.type == 'SUN':
                tabWrite("parallel\n")
                tabWrite("point_at  <0, 0, -1>\n")  # *must* be after 'parallel'

            elif lamp.type == 'AREA':
                tabWrite("fade_distance %.6f\n" % (lamp.distance / 2.0))
                # Area lights have no falloff type, so always use blenders lamp quad equivalent
                # for those?
                tabWrite("fade_power %d\n" % 2)
                size_x = lamp.size
                samples_x = lamp.pov.shadow_ray_samples_x
                if lamp.shape == 'SQUARE':
                    size_y = size_x
                    samples_y = samples_x
                else:
                    size_y = lamp.size_y
                    samples_y = lamp.pov.shadow_ray_samples_y

                tabWrite("area_light <%.6f,0,0>,<0,%.6f,0> %d, %d\n" % \
                         (size_x, size_y, samples_x, samples_y))
                tabWrite("area_illumination\n")
                if lamp.pov.shadow_ray_sample_method == 'CONSTANT_JITTERED':
                    if lamp.pov.use_jitter:
                        tabWrite("jitter\n")
                else:
                    tabWrite("adaptive 1\n")
                    tabWrite("jitter\n")

            # No shadow checked either at global or light level:
            if(not scene.pov.use_shadows or
               (lamp.pov.shadow_method == 'NOSHADOW')):
                tabWrite("shadowless\n")

            # Sun shouldn't be attenuated. Area lights have no falloff attribute so they
            # are put to type 2 attenuation a little higher above.
            if lamp.type not in {'SUN', 'AREA'}:
                if lamp.falloff_type == 'INVERSE_SQUARE':
                    tabWrite("fade_distance %.6f\n" % (sqrt(lamp.distance/2.0)))
                    tabWrite("fade_power %d\n" % 2)  # Use blenders lamp quad equivalent
                elif lamp.falloff_type == 'INVERSE_LINEAR':
                    tabWrite("fade_distance %.6f\n" % (lamp.distance / 2.0))
                    tabWrite("fade_power %d\n" % 1)  # Use blenders lamp linear
                elif lamp.falloff_type == 'CONSTANT':
                    tabWrite("fade_distance %.6f\n" % (lamp.distance / 2.0))
                    tabWrite("fade_power %d\n" % 3)
                    # Use blenders lamp constant equivalent no attenuation.
                # Using Custom curve for fade power 3 for now.
                elif lamp.falloff_type == 'CUSTOM_CURVE':
                    tabWrite("fade_power %d\n" % 4)

            writeMatrix(matrix)

            tabWrite("}\n")

            lampCount += 1

            # v(A,B) rotates vector A about origin by vector B.
            file.write("#declare lampTarget%s= vrotate(<%.4g,%.4g,%.4g>,<%.4g,%.4g,%.4g>);\n" % \
                       (lampCount, -(ob.location.x), -(ob.location.y), -(ob.location.z),
                        ob.rotation_euler.x, ob.rotation_euler.y, ob.rotation_euler.z))

####################################################################################################
    def exportRainbows(rainbows):
        """write all POV rainbows primitives to exported file """
        for ob in rainbows:
            povdataname = ob.data.name #enough?
            angle = degrees(ob.data.spot_size/2.5) #radians in blender (2
            width = ob.data.spot_blend *10
            distance = ob.data.shadow_buffer_clip_start
            #eps=0.0000001
            #angle = br/(cr+eps) * 10 #eps is small epsilon variable to avoid dividing by zero
            #width = ob.dimensions[2] #now let's say width of rainbow is the actual proxy height
            # formerly:
            #cz-bz # let's say width of the rainbow is height of the cone (interfacing choice

            # v(A,B) rotates vector A about origin by vector B.
            # and avoid a 0 length vector by adding 1

            # file.write("#declare %s_Target= vrotate(<%.6g,%.6g,%.6g>,<%.4g,%.4g,%.4g>);\n" % \
                       # (povdataname, -(ob.location.x+0.1), -(ob.location.y+0.1), -(ob.location.z+0.1),
                        # ob.rotation_euler.x, ob.rotation_euler.y, ob.rotation_euler.z))

            direction = (ob.location.x,ob.location.y,ob.location.z) # not taking matrix into account
            rmatrix = global_matrix @ ob.matrix_world

            #ob.rotation_euler.to_matrix().to_4x4() * mathutils.Vector((0,0,1))
            # XXX Is result of the below offset by 90 degrees?
            up =ob.matrix_world.to_3x3()[1].xyz #* global_matrix


            # XXX TO CHANGE:
            #formerly:
            #tabWrite("#declare %s = rainbow {\n"%povdataname)

            # clumsy for now but remove the rainbow from instancing
            # system because not an object. use lamps later instead of meshes

            #del data_ref[dataname]
            tabWrite("rainbow {\n")

            tabWrite("angle %.4f\n"%angle)
            tabWrite("width %.4f\n"%width)
            tabWrite("distance %.4f\n"%distance)
            tabWrite("arc_angle %.4f\n"%ob.pov.arc_angle)
            tabWrite("falloff_angle %.4f\n"%ob.pov.falloff_angle)
            tabWrite("direction <%.4f,%.4f,%.4f>\n"%rmatrix.translation[:])
            tabWrite("up <%.4f,%.4f,%.4f>\n"%(up[0],up[1],up[2]))
            tabWrite("color_map {\n")
            tabWrite("[0.000  color srgbt<1.0, 0.5, 1.0, 1.0>]\n")
            tabWrite("[0.130  color srgbt<0.5, 0.5, 1.0, 0.9>]\n")
            tabWrite("[0.298  color srgbt<0.2, 0.2, 1.0, 0.7>]\n")
            tabWrite("[0.412  color srgbt<0.2, 1.0, 1.0, 0.4>]\n")
            tabWrite("[0.526  color srgbt<0.2, 1.0, 0.2, 0.4>]\n")
            tabWrite("[0.640  color srgbt<1.0, 1.0, 0.2, 0.4>]\n")
            tabWrite("[0.754  color srgbt<1.0, 0.5, 0.2, 0.6>]\n")
            tabWrite("[0.900  color srgbt<1.0, 0.2, 0.2, 0.7>]\n")
            tabWrite("[1.000  color srgbt<1.0, 0.2, 0.2, 1.0>]\n")
            tabWrite("}\n")


            povMatName = "Default_texture"
            #tabWrite("texture {%s}\n"%povMatName)
            write_object_modifiers(scene,ob,file)
            #tabWrite("rotate x*90\n")
            #matrix = global_matrix @ ob.matrix_world
            #writeMatrix(matrix)
            tabWrite("}\n")
            #continue #Don't render proxy mesh, skip to next object

################################XXX LOFT, ETC.
    def exportCurves(scene, ob):
        """write all curves based POV primitives to exported file """
        name_orig = "OB" + ob.name
        dataname_orig = "DATA" + ob.data.name

        name = string_strip_hyphen(bpy.path.clean_name(name_orig))
        dataname = string_strip_hyphen(bpy.path.clean_name(dataname_orig))

        global_matrix = mathutils.Matrix.Rotation(-pi / 2.0, 4, 'X')
        matrix = global_matrix @ ob.matrix_world
        bezier_sweep = False
        if ob.pov.curveshape == 'sphere_sweep':
            #inlined spheresweep macro, which itself calls Shapes.inc:
            file.write('        #include "shapes.inc"\n')

            file.write('        #macro Shape_Bezierpoints_Sphere_Sweep(_merge_shape, _resolution, _points_array, _radius_array)\n')
            file.write('        //input adjusting and inspection\n')
            file.write('        #if(_resolution <= 1)\n')
            file.write('            #local res = 1;\n')
            file.write('        #else\n')
            file.write('            #local res = int(_resolution);\n')
            file.write('        #end\n')
            file.write('        #if(dimensions(_points_array) != 1 | dimensions(_radius_array) != 1)\n')
            file.write('            #error ""\n')
            file.write('        #elseif(div(dimension_size(_points_array,1),4) - dimension_size(_points_array,1)/4 != 0)\n')
            file.write('            #error ""\n')
            file.write('        #elseif(dimension_size(_points_array,1) != dimension_size(_radius_array,1))\n')
            file.write('            #error ""\n')
            file.write('        #else\n')
            file.write('            #local n_of_seg = div(dimension_size(_points_array,1), 4);\n')
            file.write('            #local ctrl_pts_array = array[n_of_seg]\n')
            file.write('            #local ctrl_rs_array = array[n_of_seg]\n')
            file.write('            #for(i, 0, n_of_seg-1)\n')
            file.write('                #local ctrl_pts_array[i] = array[4] {_points_array[4*i], _points_array[4*i+1], _points_array[4*i+2], _points_array[4*i+3]}\n')
            file.write('                #local ctrl_rs_array[i] = array[4] {abs(_radius_array[4*i]), abs(_radius_array[4*i+1]), abs(_radius_array[4*i+2]), abs(_radius_array[4*i+3])}\n')
            file.write('            #end\n')
            file.write('        #end\n')

            file.write('        //drawing\n')
            file.write('        #local mockup1 =\n')
            file.write('        #if(_merge_shape) merge{ #else union{ #end\n')
            file.write('            #for(i, 0, n_of_seg-1)\n')
            file.write('                #local has_head = true;\n')
            file.write('                #if(i = 0)\n')
            file.write('                    #if(vlength(ctrl_pts_array[i][0]-ctrl_pts_array[n_of_seg-1][3]) = 0 & ctrl_rs_array[i][0]-ctrl_rs_array[n_of_seg-1][3] <= 0)\n')
            file.write('                        #local has_head = false;\n')
            file.write('                    #end\n')
            file.write('                #else\n')
            file.write('                    #if(vlength(ctrl_pts_array[i][0]-ctrl_pts_array[i-1][3]) = 0 & ctrl_rs_array[i][0]-ctrl_rs_array[i-1][3] <= 0)\n')
            file.write('                        #local has_head = false;\n')
            file.write('                    #end\n')
            file.write('                #end\n')
            file.write('                #if(has_head = true)\n')
            file.write('                    sphere{\n')
            file.write('                    ctrl_pts_array[i][0], ctrl_rs_array[i][0]\n')
            file.write('                    }\n')
            file.write('                #end\n')
            file.write('                #local para_t = (1/2)/res;\n')
            file.write('                #local this_point = ctrl_pts_array[i][0]*pow(1-para_t,3) + ctrl_pts_array[i][1]*3*pow(1-para_t,2)*para_t + ctrl_pts_array[i][2]*3*(1-para_t)*pow(para_t,2) + ctrl_pts_array[i][3]*pow(para_t,3);\n')
            file.write('                #local this_radius = ctrl_rs_array[i][0]*pow(1-para_t,3) + ctrl_rs_array[i][1]*3*pow(1-para_t,2)*para_t + ctrl_rs_array[i][2]*3*(1-para_t)*pow(para_t,2) + ctrl_rs_array[i][3]*pow(para_t,3);\n')
            file.write('                #if(vlength(this_point-ctrl_pts_array[i][0]) > abs(this_radius-ctrl_rs_array[i][0]))\n')
            file.write('                    object{\n')
            file.write('                    Connect_Spheres(ctrl_pts_array[i][0], ctrl_rs_array[i][0], this_point, this_radius)\n')
            file.write('                    }\n')
            file.write('                #end\n')
            file.write('                sphere{\n')
            file.write('                this_point, this_radius\n')
            file.write('                }\n')
            file.write('                #for(j, 1, res-1)\n')
            file.write('                    #local last_point = this_point;\n')
            file.write('                    #local last_radius = this_radius;\n')
            file.write('                    #local para_t = (1/2+j)/res;\n')
            file.write('                    #local this_point = ctrl_pts_array[i][0]*pow(1-para_t,3) + ctrl_pts_array[i][1]*3*pow(1-para_t,2)*para_t + ctrl_pts_array[i][2]*3*(1-para_t)*pow(para_t,2) + ctrl_pts_array[i][3]*pow(para_t,3);\n')
            file.write('                    #local this_radius = ctrl_rs_array[i][0]*pow(1-para_t,3) + ctrl_rs_array[i][1]*3*pow(1-para_t,2)*para_t + ctrl_rs_array[i][2]*3*(1-para_t)*pow(para_t,2) + ctrl_rs_array[i][3]*pow(para_t,3);\n')
            file.write('                    #if(vlength(this_point-last_point) > abs(this_radius-last_radius))\n')
            file.write('                        object{\n')
            file.write('                        Connect_Spheres(last_point, last_radius, this_point, this_radius)\n')
            file.write('                        }\n')
            file.write('                    #end\n')
            file.write('                    sphere{\n')
            file.write('                    this_point, this_radius\n')
            file.write('                    }\n')
            file.write('                #end\n')
            file.write('                #local last_point = this_point;\n')
            file.write('                #local last_radius = this_radius;\n')
            file.write('                #local this_point = ctrl_pts_array[i][3];\n')
            file.write('                #local this_radius = ctrl_rs_array[i][3];\n')
            file.write('                #if(vlength(this_point-last_point) > abs(this_radius-last_radius))\n')
            file.write('                    object{\n')
            file.write('                    Connect_Spheres(last_point, last_radius, this_point, this_radius)\n')
            file.write('                    }\n')
            file.write('                #end\n')
            file.write('                sphere{\n')
            file.write('                this_point, this_radius\n')
            file.write('                }\n')
            file.write('            #end\n')
            file.write('        }\n')
            file.write('        mockup1\n')
            file.write('        #end\n')

            for spl in ob.data.splines:
                if spl.type == "BEZIER":
                    bezier_sweep = True
        if ob.pov.curveshape in {'loft','birail'}:
            n=0
            for spline in ob.data.splines:
                n+=1
                tabWrite('#declare %s%s=spline {\n'%(dataname,n))
                tabWrite('cubic_spline\n')
                lp = len(spline.points)
                delta = 1/(lp)
                d=-delta
                point = spline.points[lp-1]
                x,y,z,w  = point.co[:]
                tabWrite('%.6f, <%.6f,%.6f,%.6f>\n'%(d,x,y,z))
                d+=delta
                for point in spline.points:
                    x,y,z,w  = point.co[:]
                    tabWrite('%.6f, <%.6f,%.6f,%.6f>\n'%(d,x,y,z))
                    d+=delta
                for i in range(2):
                    point = spline.points[i]
                    x,y,z,w  = point.co[:]
                    tabWrite('%.6f, <%.6f,%.6f,%.6f>\n'%(d,x,y,z))
                    d+=delta
                tabWrite('}\n')
            if ob.pov.curveshape in {'loft'}:
                n = len(ob.data.splines)
                tabWrite('#declare %s = array[%s]{\n'%(dataname,(n+3)))
                tabWrite('spline{%s%s},\n'%(dataname,n))
                for i in range(n):
                    tabWrite('spline{%s%s},\n'%(dataname,(i+1)))
                tabWrite('spline{%s1},\n'%(dataname))
                tabWrite('spline{%s2}\n'%(dataname))
                tabWrite('}\n')
            # Use some of the Meshmaker.inc macro, here inlined
            file.write('#macro CheckFileName(FileName)\n')
            file.write('   #local Len=strlen(FileName);\n')
            file.write('   #if(Len>0)\n')
            file.write('      #if(file_exists(FileName))\n')
            file.write('         #if(Len>=4)\n')
            file.write('            #local Ext=strlwr(substr(FileName,Len-3,4))\n')
            file.write('            #if (strcmp(Ext,".obj")=0 | strcmp(Ext,".pcm")=0 | strcmp(Ext,".arr")=0)\n')
            file.write('               #local Return=99;\n')
            file.write('            #else\n')
            file.write('               #local Return=0;\n')
            file.write('            #end\n')
            file.write('         #else\n')
            file.write('            #local Return=0;\n')
            file.write('         #end\n')
            file.write('      #else\n')
            file.write('         #if(Len>=4)\n')
            file.write('            #local Ext=strlwr(substr(FileName,Len-3,4))\n')
            file.write('            #if (strcmp(Ext,".obj")=0 | strcmp(Ext,".pcm")=0 | strcmp(Ext,".arr")=0)\n')
            file.write('               #if (strcmp(Ext,".obj")=0)\n')
            file.write('                  #local Return=2;\n')
            file.write('               #end\n')
            file.write('               #if (strcmp(Ext,".pcm")=0)\n')
            file.write('                  #local Return=3;\n')
            file.write('               #end\n')
            file.write('               #if (strcmp(Ext,".arr")=0)\n')
            file.write('                  #local Return=4;\n')
            file.write('               #end\n')
            file.write('            #else\n')
            file.write('               #local Return=1;\n')
            file.write('            #end\n')
            file.write('         #else\n')
            file.write('            #local Return=1;\n')
            file.write('         #end\n')
            file.write('      #end\n')
            file.write('   #else\n')
            file.write('      #local Return=1;\n')
            file.write('   #end\n')
            file.write('   (Return)\n')
            file.write('#end\n')

            file.write('#macro BuildSpline(Arr, SplType)\n')
            file.write('   #local Ds=dimension_size(Arr,1);\n')
            file.write('   #local Asc=asc(strupr(SplType));\n')
            file.write('   #if(Asc!=67 & Asc!=76 & Asc!=81) \n')
            file.write('      #local Asc=76;\n')
            file.write('      #debug "\nWrong spline type defined (C/c/L/l/N/n/Q/q), using default linear_spline\\n"\n')
            file.write('   #end\n')
            file.write('   spline {\n')
            file.write('      #switch (Asc)\n')
            file.write('         #case (67) //C  cubic_spline\n')
            file.write('            cubic_spline\n')
            file.write('         #break\n')
            file.write('         #case (76) //L  linear_spline\n')
            file.write('            linear_spline\n')
            file.write('         #break\n')
            file.write('         #case (78) //N  linear_spline\n')
            file.write('            natural_spline\n')
            file.write('         #break\n')
            file.write('         #case (81) //Q  Quadratic_spline\n')
            file.write('            quadratic_spline\n')
            file.write('         #break\n')
            file.write('      #end\n')
            file.write('      #local Add=1/((Ds-2)-1);\n')
            file.write('      #local J=0-Add;\n')
            file.write('      #local I=0;\n')
            file.write('      #while (I<Ds)\n')
            file.write('         J\n')
            file.write('         Arr[I]\n')
            file.write('         #local I=I+1;\n')
            file.write('         #local J=J+Add;\n')
            file.write('      #end\n')
            file.write('   }\n')