Batch Export GLTF (w/ DRACO & Punctual Lights, optimised settings for web/streaming)

batch_gltf.py

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# <pep8 compliant>

# From: https://blender.stackexchange.com/a/211096/
# Based on: https://blender.stackexchange.com/a/31852/

bl_info = {
	"name": "Batch Export GLTF",
	"author": "brockmann",
	"version": (0, 1),
	"blender": (2, 91, 0),
	"location": "File > Import-Export",
	"description": "Batch Export GLTF files",
	"warning": "",
	"wiki_url": "",
	"tracker_url": "",
	"category": "Import-Export"
}


import bpy
import os

from bpy_extras.io_utils import ExportHelper

from bpy.props import (BoolProperty,
					IntProperty,
					FloatProperty,
					StringProperty,
					EnumProperty,
					CollectionProperty
					)


class ExportMultiGLTF(bpy.types.Operator, ExportHelper):
	"""Batch export objects as gltf files"""
	bl_idname = "export_scene.batch_gltf"
	bl_label = "Batch export GLTF"
	bl_options = {'PRESET', 'UNDO'}

	# ExportHelper mixin class uses this
	filename_ext = ""

	filter_glob: StringProperty(
			default='*.glb;*.gltf', 
			options={'HIDDEN'}
	)

	# List of operator properties, the attributes will be assigned
	# to the class instance from the operator setting before calling.
	batch_export_format: EnumProperty(
		name='Format',
		items=(('GLB', 'glTF Binary (.glb)',
				'Exports a single file, with all data packed in binary form. '
				'Most efficient and portable, but more difficult to edit later'),
			('GLTF_EMBEDDED', 'glTF Embedded (.gltf)',
				'Exports a single file, with all data packed in JSON. '
				'Less efficient than binary, but easier to edit later'),
			('GLTF_SEPARATE', 'glTF Separate (.gltf + .bin + textures)',
				'Exports multiple files, with separate JSON, binary and texture data. '
				'Easiest to edit later')),
		description=(
			'Output format and embedding options. Binary is most efficient, '
			'but JSON (embedded or separate) may be easier to edit later'
		),
		default='GLTF_SEPARATE'
	)

	batch_export_copyright: StringProperty(
		name='Copyright',
		description='Legal rights and conditions for the model',
		default=''
	)
	
	batch_export_selection: BoolProperty(
		name="Selection Only",
		description="Export selected objects only",
		default=True,
	)

	batch_export_image_format: EnumProperty(
		name='Images',
		items=(('AUTO', 'Automatic',
				'Save PNGs as PNGs and JPEGs as JPEGs.\n'
				'If neither one, use PNG'),
				('JPEG', 'JPEG Format (.jpg)',
				'Save images as JPEGs. (Images that need alpha are saved as PNGs though.)\n'
				'Be aware of a possible loss in quality'),
			),
		description=(
			'Output format for images. PNG is lossless and generally preferred, but JPEG might be preferable for web '
			'applications due to the smaller file size'
		),
		default='JPEG'
	)

	batch_export_levels: IntProperty(
		name='Collection Levels',
		description='Set the levels of collections',
		default=2
	)

	batch_export_materials: EnumProperty(
		name='Materials',
		items=(('EXPORT', 'Export',
		'Export all materials used by included objects'),
		('PLACEHOLDER', 'Placeholder',
		'Do not export materials, but write multiple primitive groups per mesh, keeping material slot information'),
		('NONE', 'No export',
		'Do not export materials, and combine mesh primitive groups, losing material slot information')),
		description='Export materials ',
		default='EXPORT'
	)

	batch_export_colors: BoolProperty(
		name='Export Vertex Colors',
		description='Export vertex colors with meshes',
		default=True
	)

	batch_export_cameras: BoolProperty(
		name='Export Cameras',
		description='Export cameras',
		default=False
	)

	batch_export_extras: BoolProperty(
		name='Export Custom Properties',
		description='Export custom properties as glTF extras',
		default=False
	)

	batch_export_apply: BoolProperty(
		name='Export Apply Modifiers',
		description='Apply modifiers (excluding Armatures) to mesh objects -'
					'WARNING: prevents exporting shape keys',
		default=False
	)

	batch_export_yup: BoolProperty(
		name='+Y Up',
		description='Export using glTF convention, +Y up',
		default=True
	)
	
	batch_export_draco_mesh_compression_enable: BoolProperty(
		name="Draco Compression",
		description="Compress mesh using Draco",
		default=True,
	)

	batch_export_lights: BoolProperty(
		name="Punctual Lights",
		description="Export directional, point, and spot lights. Uses “KHR_lights_punctual” glTF extension",
		default=True,
	)

	def execute(self, context):                

		# get the folder
		folder_path = os.path.dirname(self.filepath)

		# get objects selected in the viewport
		viewport_selection = context.selected_objects

		# get export objects
		obj_export_list = viewport_selection
		if self.batch_export_selection == False:
			obj_export_list = [i for i in context.scene.objects]

		# deselect all objects
		bpy.ops.object.select_all(action='DESELECT')

		for item in obj_export_list:
			item.select_set(True)
			#if item.type == 'MESH':
			file_path = os.path.join(folder_path, "{}.{}".format(item.name, self.batch_export_format))

			bpy.ops.export_scene.gltf(
				filepath = file_path,
				use_selection = self.batch_export_selection,
				export_format = self.batch_export_format,
				export_copyright = self.batch_export_copyright,
				export_image_format = self.batch_export_image_format,
				export_materials = self.batch_export_materials,
				export_colors = self.batch_export_colors,
				export_cameras = self.batch_export_cameras,
				export_extras = self.batch_export_extras,
				export_yup = self.batch_export_yup,
				export_apply = self.batch_export_apply,
				export_draco_mesh_compression_enable = self.batch_export_draco_mesh_compression_enable,
				export_lights = self.batch_export_lights,
			)
				
			item.select_set(False)

		# restore viewport selection
		for ob in viewport_selection:
			ob.select_set(True)

		return {'FINISHED'}


# Only needed if you want to add into a dynamic menu
def menu_func_import(self, context):
	self.layout.operator(ExportMultiGLTF.bl_idname, text="Batch Export glTF 2.0 (.glb/.gltf)")


def register():
	bpy.utils.register_class(ExportMultiGLTF)
	bpy.types.TOPBAR_MT_file_export.append(menu_func_import)


def unregister():
	bpy.utils.unregister_class(ExportMultiGLTF)
	bpy.types.TOPBAR_MT_file_export.remove(menu_func_import)


if __name__ == "__main__":
	register()

	# test call
	#bpy.ops.export_scene.multiple_objs('INVOKE_DEFAULT')