[MapProxy] Multi-layer transparency problem

[DeDuikertjes]

Dejan,

I've created this patch which helps when mapproxy has to overlay 
multiple layers with opacity and an alpha channel.
Maybe something along these lines can help you as well:

mapproxy/image/__init__.py:
     layer_img = layer.as_image()
     if (layer.image_opts and layer.image_opts.opacity is not None
         and layer.image_opts.opacity < 1.0):
-        layer_img = layer_img.convert(img.mode)
-        img = Image.blend(img, layer_img, layer.image_opts.opacity)
+        if layer_img.mode == 'RGBA':
+            alpha = layer_img.split()[3]
+            alpha = 
ImageEnhance.Brightness(alpha).enhance(layer.image_opts.opacity)
+            layer_img.putalpha(alpha)
+            img.paste(layer_img, (0, 0), layer_img)
+        else:
+            layer_img = layer_img.convert(img.mode)
+            img = Image.blend(img, layer_img, layer.image_opts.opacity)
     else:
         if layer_img.mode == 'RGBA':
             # paste w transparency mask from layer

mapproxy/platform/image.py:
Everywhere I've substituted:
Image, ImageColor, ImageDraw, ImageFont, ImagePalette, ImageChops
by:
Image, ImageColor, ImageDraw, ImageFont, ImagePalette, ImageChops, 
ImageEnhance

@Oliver: is there any chance that this patch will become part of mapproxy?
Do I have to do something for that?

MArco



Op 16-1-2012 18:00, mapproxy-request at lists.osgeo.org schreef:
> Re: [MapProxy] Multi-layer transparency problem