commit 075f3d9a24f6ae9312abc241d545660bed162644
Author: Klaus-Uwe Mitterer <git@kumi.email>
Date:   Tue Sep 18 19:30:00 2018 +0200

    Initial commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..fffc64d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+__pycache__
+*.swp
diff --git a/worker.py b/worker.py
new file mode 100644
index 0000000..7877cae
--- /dev/null
+++ b/worker.py
@@ -0,0 +1,275 @@
+import PIL.Image
+import urllib.request
+import io
+import math
+import subprocess
+
+def tiles_to_equirectangular_blender(back, right, front, left, top, bottom):
+    left.save("left.png")
+    front.save("front.png")
+    right.save("right.png")
+    back.save("back.png")
+    bottom.save("bottom.png")
+    top.save("top.png")
+
+    height = left.size[0] * 2
+    width = left.size[0] * 4
+
+    try:
+        process = subprocess.Popen(
+            ['cube2sphere', 'front.png', 'back.png', 'right.png', 'left.png',
+             'top.png', 'bottom.png', '-f', 'png', "-r", 
+             str(width), str(height)]
+            )
+
+        process.wait()
+
+    except:
+        print("No imports here.")
+
+def tiles_to_equirectangular(back, right, front, left, top, bottom):
+    dim = left.size[0]
+
+    raw = []
+
+    t_width = dim * 4
+    t_height = dim * 2
+
+    for y in range(t_height):
+        v = 1.0 - (float(y) / t_height)
+        phi = v * math.pi
+
+        for x in range(t_width):
+            u = float(x) / t_width
+            theta = u * math.pi * 2
+
+            x = math.cos(theta) * math.sin(phi)
+            y = math.sin(theta) * math.sin(phi)
+            z = math.cos(phi)
+
+            a = max(abs(x), abs(y), abs(z))
+
+            xx = x / a
+            yy = y / a
+            zz = z / a
+
+            if yy == -1:
+                currx = int(((-1 * math.tan(math.atan(x / y)) + 1.0) / 2.0) * dim)
+                ystore = int(((-1 * math.tan(math.atan(z / y)) + 1.0) / 2.0) * (dim - 1))
+                part = left
+
+            elif xx == 1:
+                currx = int(((math.tan(math.atan(y / x)) + 1.0) / 2.0) * dim)
+                ystore = int(((math.tan(math.atan(z / x)) + 1.0) / 2.0) * dim)
+                part = front
+
+            elif yy == 1:
+                currx = int(((-1 * math.tan(math.atan(x / y)) + 1.0) / 2.0) * dim)
+                ystore = int(((math.tan(math.atan(z / y)) + 1.0) / 2.0) * (dim - 1))
+                part = right
+
+            elif xx == -1:
+                currx = int(((math.tan(math.atan(y / x)) + 1.0) / 2.0) * dim)
+                ystore = int(((-1 * math.tan(math.atan(z / x)) + 1.0) / 2.0) * (dim - 1))
+                part = back
+
+            elif zz == 1:
+                currx = int(((math.tan(math.atan(y / z)) + 1.0) / 2.0) * dim)
+                ystore = int(((-1 * math.tan(math.atan(x / z)) + 1.0) / 2.0) * (dim - 1))
+                part = bottom
+
+            else:
+                currx = int(((-1 * math.tan(math.atan(y / z)) + 1.0) / 2.0) * dim)
+                ystore = int(((-1 * math.tan(math.atan(x / z)) + 1.0) / 2.0) * (dim - 1))
+                part = top
+
+            curry = (dim - 1) if ystore > (dim - 1) else ystore
+
+            if curry > (dim - 1):
+                curry = dim - 1
+
+            if currx > (dim - 1):
+                currx = dim - 1
+
+            raw.append(part.getpixel((currx, curry)))
+
+    output = PIL.Image.new("RGB", (t_width, t_height))
+    output.putdata(raw)
+
+    return output
+
+def krpano_normalize(url):
+    '''
+    Takes the URL of any image in a krpano panorama and returns a string
+    with substitutable variables for image IDs.
+
+    :param url: URL of an image contained in a krpano panorama
+    :return: string with substitutable variables or False if URL invalid
+    '''
+
+    try:
+        with urllib.request.urlopen(url) as res:
+            assert res.getcode() == 200
+
+        parts = url.split("/")
+
+        assert "_" in parts[-1]
+        parts[-1] = "%i_%i.jpg"
+        parts[-2] = "%i"
+        parts[-3] = "%i"
+
+        return "/".join(parts)
+
+    except:
+        return False
+
+def krpano_getmaxzoom(schema):
+    '''
+    Takes a normalized string from krpano_normalize() and returns the maximum
+    zoom level available.
+
+    :param schema: normalized URL format output by krpano_normalize()
+    :return: int value of largest available zoom level
+    '''
+
+    l = 0
+
+    while True:
+        try:
+            url = schema % (0, l+1, 0, 0)
+            with urllib.request.urlopen(url) as res:
+                assert res.getcode() == 200
+                l += 1
+        except:
+            return l
+
+def krpano_export(schema):
+    '''
+    Takes a normalized string from krpano_normalize() and returns a list of
+    lists of lists containing all images fit for passing into stitch().
+
+    :param schema: normalized URL format output by krpano_normalize()
+    :return: list of lists of lists of PIL.Image() objects for krpano_stitch()
+    '''
+
+    maxzoom = krpano_getmaxzoom(schema)
+    output = []
+
+    for tile in range(6):
+        t_array = []
+        y = 0
+
+        while True:
+            r_array = []
+            x = 0
+
+            while True:
+                try:
+                    res = urllib.request.urlopen(schema % (tile, maxzoom, y, x))
+                    assert res.getcode() == 200
+                    fo = io.BytesIO(res.read())
+                    img = PIL.Image.open(fo)
+                    r_array.append(img)
+                    x += 1
+                except Exception as e:
+                    break
+
+            if not r_array:
+                break
+
+            t_array.append(r_array)
+            y += 1
+
+        output.append(t_array)
+
+    return output
+
+def krpano_process(url):
+    '''
+    Takes the URL of any image in a krpano panorama and returns a list of
+    lists of lists containing all images fit for passing into stitch().
+
+    :param url: URL of an image contained in a krpano panorama
+    :return: list of lists of lists of PIL.Image() objects for krpano_stitch()
+    '''
+
+    schema = krpano_normalize(url)
+
+    if not schema:
+        raise ValueError("%s does not seem to be a valid krpano URL." % url)
+
+    return krpano_export(schema)
+
+def krpano_stitch(tiles):
+    '''
+    Takes a list of lists of lists containing PIL Image objects and stitches
+    them into one. Each box tile (first-order lists), line (second-order) and
+    column (third-order) must be equal in height and width.
+
+    :param faces: list of lists of lists containing PIL.Image objects
+    :return: list of stitched PIL.Image objects
+    '''
+
+    output = []
+
+    for tile in tiles:
+        output.append(stitch(tile))
+
+    return output
+
+def krpano_to_equirectangular(url):
+    images = krpano_process(url)
+    stitched = krpano_stitch(images)
+    return tiles_to_equirectangular_blender(*stitched)
+
+def stitch(images):
+    '''
+    Takes a list of lists containing PIL Image objects and stitches them into
+    one. Each line (first-order lists) and column (second-order) must be equal
+    in height and width.
+
+    :param images: list of lists containing PIL.Image objects
+    :return: stitched PIL.Image object
+    '''
+
+    t_height = 0 # Total height of resulting image
+    t_width = 0 # Total width of resulting image
+
+    '''Calculate height of final image by adding up heights of the first images
+    of each row.'''
+
+    for row in images:
+        w, h = row[0].size
+        t_height += h
+
+    '''Calculate width of final image by adding up widths of the images in the
+    first row.'''
+
+    for image in images[0]:
+        w, h = image.size
+        t_width += w
+
+    '''Generate output Image object using calculated height and width.'''
+
+    output = PIL.Image.new("RGB", (t_width, t_height))
+
+    curry = 0 # Current y position (top = 0)
+
+    for row in images:
+        currx = 0 # Current x position (left = 0)
+        y_offset = 0 # How far down we have to go for the next line
+
+        for image in row:
+
+            '''Paste line of images into the output image.'''
+
+            output.paste(im=image, box=(currx, curry))
+            w, h = image.size
+            currx += w
+
+            if not y_offset:
+                y_offset = h
+
+        curry += y_offset
+
+    return output