image_flatten_overlay.py

import os
import os
import sys
import subprocess
import threading

import bpy
from bpy.props import StringProperty, EnumProperty
from bpy_extras.io_utils import ExportHelper


class TKD_Controller_Thread(threading.Thread):
    def __init__(self, commands, basedir, caller):
        self.commands = commands
        self.basedir = basedir
        self.caller = caller
        threading.Thread.__init__(self)

    def run(self):
        initial_location = os.getcwd()
        try:
            os.chdir(self.basedir)
            print("starting controlled thread")
            subprocess.Popen(self.commands)
            filepath = os.path.join(self.basedir, self.commands[-1])
            bpy.data.images.load(filepath)

        except:
            self.caller.report({'WARNING'}, 'check console for imagemagick output')

        os.chdir(initial_location)        

class TKD_Callback_Operator(bpy.types.Operator):
    bl_idname = "image.tkd_callback_operator"
    bl_label = "TKD image merger callback"
    bl_options = {'REGISTER', 'UNDO'}

    fn_name = StringProperty(default='')

    def execute(self, context):
        scn = context.scene
        fn_name = self.fn_name

        if fn_name == "merge and load":
            output_name = scn.TKD_composite_image_name
            if not output_name:
                self.report({'WARNING'}, 'must give an outputname')
            else: 

                command = "convert {0} {1} -flatten {2}"
                a = scn.TKD_base_image_name
                b = scn.TKD_overlay_image_name
                c = output_name
                
                if not any([c.endswith(a) for a in ['.png', '.jpg', '.tiff']]):
                    c = output_name + '.png'
                
                command = command.format(a, b, c)

                th = TKD_Controller_Thread(command.split(), basedir=scn.TKD_base_path_name, caller=self)
                th.start()


        return {'FINISHED'}


class TKD_DirectorySelectorOperator(bpy.types.Operator, ExportHelper):
    bl_idname = "image.tkd_folder_selector"
    bl_label = "image folder"

    filename_ext = "."
    use_filter_folder = True

    def execute(self, context):
        # even if you pick a file i'll strip it and get the dirname
        fdir = self.properties.filepath
        dp = os.path.dirname(fdir)
        context.scene.TKD_base_path_name = dp
        return{'FINISHED'}


class TKD_image_composite(bpy.types.Panel):
    """Creates a Panel in the Object properties window"""
    bl_label = "Overlay Images"
    bl_idname = "IMAGE_PT_overlay"
    bl_space_type = 'IMAGE_EDITOR'
    bl_region_type = 'UI'

    def draw(self, context):
        layout = self.layout
        layout.row().label(text="by folder")
        row = layout.row(align=True)
        row.prop(context.scene, "TKD_base_path_name", text="")
        row.operator("image.tkd_folder_selector", icon="FILE_FOLDER", text="")
        
        if not context.scene.TKD_base_path_name:
            return
        
        col = layout.column()
        col.label(text="base image")
        col.prop(context.scene, "TKD_base_image_name", text="")
        col.label(text="region to add")
        col.prop(context.scene, "TKD_overlay_image_name", text="")
        col.label(text="give it a name (auto-postfix .png)")
        col.prop(context.scene, "TKD_composite_image_name", text="")        
        op = col.operator("image.tkd_callback_operator", text="Merge and load")
        op.fn_name = "merge and load"

scn = bpy.types.Scene

def register():
    scn.TKD_base_path_name = StringProperty()
    scn.TKD_composite_image_name = StringProperty()

    def avail_images(self, context):
        img_path = context.scene.TKD_base_path_name
        if not img_path:
            return [("","","")]
        
        items = [(t, t, "") for t in next(os.walk(img_path))[2] if t.endswith('png')]
        return items

    scn.TKD_base_image_name = EnumProperty(
        items=avail_images,
        name='base_image_files',
        description='choose file to load as base file')    
    
    scn.TKD_overlay_image_name = EnumProperty(
        items=avail_images,
        name='overlay_image_files',
        description='choose file to load as overlay file')   

    bpy.utils.register_class(TKD_Callback_Operator)
    bpy.utils.register_class(TKD_DirectorySelectorOperator)
    bpy.utils.register_class(TKD_image_composite)


def unregister():
    bpy.utils.unregister_class(TKD_image_composite)
    bpy.utils.unregister_class(TKD_DirectorySelectorOperator)
    bpy.utils.unregister_class(TKD_Callback_Operator)
    
    del scn.TKD_base_image_name
    del scn.TKD_overlay_image_name
    del scn.TKD_composite_image_name
    del scn.TKD_base_path_name

if __name__ == "__main__":
    register()