Merge branch 'blending' of https://github.com/agrif/Minecraft-Overviewer into agrif-blending

.gitignore

@@ -1 +1,8 @@
 *.pyc
+build
+
+# various forms of compiled _composite extensions
+_composite.so
+_composite.pyd
+_composite_d.pyd
+_composite.dylib

README.rst

@@ -85,6 +85,28 @@ you can use the Overviewer:
   hidden directory). You can also get this file from any of the third party
   texture packs out there.
 
+Compiling the C Extension (optional)
+------------------------------------ 
+The C Extension for Overviewer is completely optional. It provides a higher
+quality image compositing function that looks better on maps with lighting
+enabled, and a slight performance boost.
+
+If you downloaded Overviewer as a binary package, this extension may be already
+compiled for you. Overviewer emits a warning if the extension is not found, but
+will still work fine.
+
+If you have a C compiler and the Python development libraries set up, you can
+compile this extension like this::
+
+    python setup.py build
+
+Note that you need the development headers for your version of Python installed,
+look for a package named 'python-dev', 'python-devel' or similar. Also, some
+Python distributions do not install "Imaging.h" and "ImPlatform.h" properly. If
+you get errors complaining about them, you can get them from the PIL source, or
+at <http://svn.effbot.org/public/tags/pil-1.1.7/libImaging/>. Just put them in
+the same directory as "_composite.c".
+
 Running
 -------
 To generate a set of Google Map tiles, use the gmap.py script like this::

_composite.c

@@ -0,0 +1,224 @@
+/* 
+ * This file is part of the Minecraft Overviewer.
+ *
+ * Minecraft Overviewer 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 3 of the License, or (at
+ * your option) any later version.
+ *
+ * Minecraft Overviewer 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 the Overviewer.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* 
+ * This file implements a custom alpha_over function for (some) PIL
+ * images. It's designed to be used through composite.py, which
+ * includes a proxy alpha_over function that falls back to the default
+ * PIL paste if this extension is not found.
+ */
+
+#include <Python.h>
+#include <Imaging.h>
+
+/* like (a * b + 127) / 255), but much faster on most platforms
+   from PIL's _imaging.c */
+#define MULDIV255(a, b, tmp)								\
+	(tmp = (a) * (b) + 128, ((((tmp) >> 8) + (tmp)) >> 8))
+
+typedef struct
+{
+	PyObject_HEAD
+	Imaging image;
+} ImagingObject;
+
+static Imaging imaging_python_to_c(PyObject* obj)
+{
+	PyObject* im;
+	Imaging image;
+
+	/* first, get the 'im' attribute */
+	im = PyObject_GetAttrString(obj, "im");
+	if (!im)
+		return NULL;
+	
+	/* make sure 'im' is the right type */
+	if (strcmp(im->ob_type->tp_name, "ImagingCore") != 0)
+	{
+		/* it's not -- raise an error and exit */
+		PyErr_SetString(PyExc_TypeError, "image attribute 'im' is not a core Imaging type");
+		return NULL;
+	}
+	
+	image = ((ImagingObject*)im)->image;
+	Py_DECREF(im);
+	return image;
+}
+
+static PyObject* _composite_alpha_over(PyObject* self, PyObject* args)
+{
+	/* raw input python variables */
+	PyObject* dest, * src, * pos, * mask;
+	/* libImaging handles */
+	Imaging imDest, imSrc, imMask;
+	/* cached blend properties */
+	int src_has_alpha, mask_offset, mask_stride;
+	/* destination position and size */
+	int dx, dy, xsize, ysize;
+	/* source position */
+	int sx, sy;
+	/* iteration variables */
+	unsigned int x, y, i;
+	/* temporary calculation variables */
+	int tmp1, tmp2, tmp3;
+	
+	if (!PyArg_ParseTuple(args, "OOOO", &dest, &src, &pos, &mask))
+		return NULL;
+	
+	imDest = imaging_python_to_c(dest);
+	imSrc = imaging_python_to_c(src);
+	imMask = imaging_python_to_c(mask);
+	
+	if (!imDest || !imSrc || !imMask)
+		return NULL;
+	
+	/* check the various image modes, make sure they make sense */
+	if (strcmp(imDest->mode, "RGBA") != 0)
+	{
+		PyErr_SetString(PyExc_ValueError, "given destination image does not have mode \"RGBA\"");
+		return NULL;
+	}
+	
+	if (strcmp(imSrc->mode, "RGBA") != 0 && strcmp(imSrc->mode, "RGB") != 0)
+	{
+		PyErr_SetString(PyExc_ValueError, "given source image does not have mode \"RGBA\" or \"RGB\"");
+		return NULL;
+	}
+	
+	if (strcmp(imMask->mode, "RGBA") != 0 && strcmp(imMask->mode, "L") != 0)
+	{
+		PyErr_SetString(PyExc_ValueError, "given mask image does not have mode \"RGBA\" or \"L\"");
+		return NULL;
+	}
+	
+	/* make sure mask size matches src size */
+	if (imSrc->xsize != imMask->xsize || imSrc->ysize != imMask->ysize)
+	{
+		PyErr_SetString(PyExc_ValueError, "mask and source image sizes do not match");
+		return NULL;
+	}
+	
+	/* set up flags for the src/mask type */
+    src_has_alpha = (imSrc->pixelsize == 4 ? 1 : 0);
+	/* how far into image the first alpha byte resides */
+	mask_offset = (imMask->pixelsize == 4 ? 3 : 0);
+	/* how many bytes to skip to get to the next alpha byte */
+	mask_stride = imMask->pixelsize;
+	
+	/* destination position read */
+	if (!PyArg_ParseTuple(pos, "iiii", &dx, &dy, &xsize, &ysize))
+	{
+		PyErr_SetString(PyExc_TypeError, "given blend destination rect is not valid");
+		return NULL;
+	}
+	
+	/* set up the source position, size and destination position */
+	/* handle negative dest pos */
+	if (dx < 0)
+	{
+		sx = -dx;
+		dx = 0;
+	} else {
+		sx = 0;
+	}
+	
+	if (dy < 0)
+	{
+		sy = -dy;
+		dy = 0;
+	} else {
+		sy = 0;
+	}
+	
+	/* set up source dimensions */
+	xsize -= sx;
+	ysize -= sy;
+	
+	/* clip dimensions, if needed */
+	if (dx + xsize > imDest->xsize)
+		xsize = imDest->xsize - dx;
+	if (dy + ysize > imDest->ysize)
+		ysize = imDest->ysize - dy;
+	
+	/* check that there remains any blending to be done */
+	if (xsize <= 0 || ysize <= 0)
+	{
+		/* nothing to do, return */
+		Py_INCREF(dest);
+		return dest;
+	}
+	
+	for (y = 0; y < ysize; y++)
+	{
+		UINT8* out = (UINT8*) imDest->image[dy + y] + dx*4;
+		UINT8* outmask = (UINT8*) imDest->image[dy + y] + dx*4 + 3;
+		UINT8* in = (UINT8*) imSrc->image[sy + y] + sx*(imSrc->pixelsize);
+		UINT8* inmask = (UINT8*) imMask->image[sy + y] + sx*mask_stride + mask_offset;
+		
+		for (x = 0; x < xsize; x++)
+		{
+			/* special cases */
+			if (*inmask == 255 || *outmask == 0)
+			{
+				*outmask = *inmask;
+				
+				*out = *in;
+				out++, in++;
+				*out = *in;
+				out++, in++;
+				*out = *in;
+				out++, in++;
+			} else if (*inmask == 0) {
+				/* do nothing -- source is fully transparent */
+				out += 3;
+				in += 3;
+			} else {
+				/* general case */
+				int alpha = *inmask + MULDIV255(*outmask, 255 - *inmask, tmp1);
+				for (i = 0; i < 3; i++)
+				{
+					/* general case */
+					*out = MULDIV255(*in, *inmask, tmp1) + MULDIV255(MULDIV255(*out, *outmask, tmp2), 255 - *inmask, tmp3);
+					*out = (*out * 255) / alpha;
+					out++, in++;
+				}
+				
+				*outmask = alpha;
+			}
+			
+			out++;
+			if (src_has_alpha)
+				in++;
+			outmask += 4;
+			inmask += mask_stride;
+		}
+	}
+	
+	Py_INCREF(dest);
+	return dest;
+}
+
+static PyMethodDef _CompositeMethods[] =
+{
+	{"alpha_over", _composite_alpha_over, METH_VARARGS, "alpha over composite function"},
+	{NULL, NULL, 0, NULL}
+};
+
+PyMODINIT_FUNC init_composite(void)
+{
+	(void) Py_InitModule("_composite", _CompositeMethods);
+}

chunk.py

@@ -22,6 +22,7 @@ import logging
 import nbt
 import textures
 import world
+import composite
 
 """
 This module has routines related to rendering one particular chunk into an
@@ -36,7 +37,11 @@ image
 # of the dest image will have its alpha channel modified. To prevent this:
 # first use im.split() and take the third item which is the alpha channel and
 # use that as the mask. Then take the image and use im.convert("RGB") to strip
-# the image from its alpha channel, and use that as the source to paste()
+# the image from its alpha channel, and use that as the source to alpha_over()
+
+# (note that this workaround is NOT technically needed when using the
+# alpha_over extension, BUT this extension may fall back to PIL's
+# paste(), which DOES need the workaround.)
 
 def get_lvldata(filename):
     """Takes a filename and returns the Level struct, which contains all the
@@ -556,36 +561,36 @@ class ChunkRenderer(object):
             # tint the block with a color proportional to its depth
             if cave:
                 # no lighting for cave -- depth is probably more useful
-                img.paste(Image.blend(t[0],depth_colors[z],0.3), (imgx, imgy), t[1])
+                composite.alpha_over(img, Image.blend(t[0],depth_colors[z],0.3), (imgx, imgy), t[1])
             else:
                 if not self.world.lighting:
                     # no lighting at all
-                    img.paste(t[0], (imgx, imgy), t[1])
+                    composite.alpha_over(img, t[0], (imgx, imgy), t[1])
                 elif blockid in transparent_blocks:
                     # transparent means draw the whole
                     # block shaded with the current
                     # block's light
                     black_coeff, _ = self.get_lighting_coefficient(x, y, z)
-                    img.paste(Image.blend(t[0], black_color, black_coeff), (imgx, imgy), t[1])
+                    composite.alpha_over(img, Image.blend(t[0], black_color, black_coeff), (imgx, imgy), t[1])
                 else:
                     # draw each face lit appropriately,
                     # but first just draw the block
-                    img.paste(t[0], (imgx, imgy), t[1])
+                    composite.alpha_over(img, t[0], (imgx, imgy), t[1])
                     
                     # top face
                     black_coeff, face_occlude = self.get_lighting_coefficient(x, y, z + 1)
                     if not face_occlude:
-                        img.paste((0,0,0), (imgx, imgy), ImageEnhance.Brightness(facemasks[0]).enhance(black_coeff))
+                        composite.alpha_over(img, black_color, (imgx, imgy), ImageEnhance.Brightness(facemasks[0]).enhance(black_coeff))
                     
                     # left face
                     black_coeff, face_occlude = self.get_lighting_coefficient(x - 1, y, z)
                     if not face_occlude:
-                        img.paste((0,0,0), (imgx, imgy), ImageEnhance.Brightness(facemasks[1]).enhance(black_coeff))
+                        composite.alpha_over(img, black_color, (imgx, imgy), ImageEnhance.Brightness(facemasks[1]).enhance(black_coeff))
 
                     # right face
                     black_coeff, face_occlude = self.get_lighting_coefficient(x, y + 1, z)
                     if not face_occlude:
-                        img.paste((0,0,0), (imgx, imgy), ImageEnhance.Brightness(facemasks[2]).enhance(black_coeff))
+                        composite.alpha_over(img, black_color, (imgx, imgy), ImageEnhance.Brightness(facemasks[2]).enhance(black_coeff))
 
             # Draw edge lines
             if blockid in (44,): # step block
@@ -616,6 +621,8 @@ def generate_facemasks():
     toppart = textures.transform_image(white)
     leftpart = textures.transform_image_side(white)
     
+    # using the real PIL paste here (not alpha_over) because there is
+    # no alpha channel (and it's mode "L")
     top.paste(toppart, (0,0))
     left.paste(leftpart, (0,6))
     right = left.transpose(Image.FLIP_LEFT_RIGHT)

composite.py

@@ -0,0 +1,51 @@
+#    This file is part of the Minecraft Overviewer.
+#
+#    Minecraft Overviewer 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 3 of the License, or (at
+#    your option) any later version.
+#
+#    Minecraft Overviewer 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 the Overviewer.  If not, see <http://www.gnu.org/licenses/>.
+
+import logging
+
+from PIL import Image
+
+"""
+This module has an alpha-over function that is used throughout
+Overviewer. It defaults to the PIL paste function when the custom
+alpha-over extension cannot be found.
+"""
+
+extension_alpha_over = None
+try:
+    from _composite import alpha_over as _extension_alpha_over
+    extension_alpha_over = _extension_alpha_over
+except ImportError:
+    logging.warning("alpha_over extension not found; using default PIL paste()")
+
+def alpha_over(dest, src, pos_or_rect=(0, 0), mask=None):
+    """Composite src over dest, using mask as the alpha channel (if
+    given), otherwise using src's alpha channel. pos_or_rect can
+    either be a position or a rectangle, specifying where on dest to
+    put src. Falls back to dest.paste() if the alpha_over extension
+    can't be found."""
+    if mask == None:
+        mask = src
+    
+    global extension_alpha_over
+    if extension_alpha_over != None:
+        # extension ALWAYS expects rects, so convert if needed
+        if len(pos_or_rect) == 2:
+            pos_or_rect = (pos_or_rect[0], pos_or_rect[1], src.size[0], src.size[1])
+        extension_alpha_over(dest, src, pos_or_rect, mask)
+    else:
+        # fallback
+        dest.paste(src, pos_or_rect, mask)
+

quadtree.py

@@ -29,6 +29,7 @@ import util
 from PIL import Image
 
 from optimizeimages import optimize_image
+import composite
 
 
 """
@@ -449,7 +450,10 @@ def render_innertile(dest, name, imgformat, optimizeimg):
 
     # Create the actual image now
     img = Image.new("RGBA", (384, 384), (38,92,255,0))
-
+    
+    # we'll use paste (NOT alpha_over) for quadtree generation because
+    # this is just straight image stitching, not alpha blending
+    
     if q0path:
         try:
             quad0 = Image.open(q0path).resize((192,192), Image.ANTIALIAS)
@@ -613,7 +617,7 @@ def render_worldtile(chunks, colstart, colend, rowstart, rowend, path, imgformat
         xpos = -192 + (col-colstart)*192
         ypos = -96 + (row-rowstart)*96
 
-        tileimg.paste(chunkimg.convert("RGB"), (xpos, ypos), chunkimg)
+        composite.alpha_over(tileimg, chunkimg.convert("RGB"), (xpos, ypos), chunkimg)
 
     # Save them
     tileimg.save(imgpath)

setup.py

@@ -1,13 +1,68 @@
-from distutils.core import setup
+from distutils.core import setup, Extension
-import py2exe
+from distutils.command.build import build
+from distutils.command.clean import clean
+from distutils.dir_util import remove_tree
+from distutils import log
+import os, os.path
 
-setup(console=['gmap.py'],
+try:
-        data_files=[('textures', ['textures/lava.png', 'textures/water.png']),
+    import py2exe
-		('', ['template.html'])],
+except ImportError:
-        zipfile = None,
+    py2exe = None
-        options = {'py2exe': {
+
-            'bundle_files': 1,
+# now, setup the keyword arguments for setup
-            }},
+# (because we don't know until runtime if py2exe is available)
+setup_kwargs = {}
+setup_kwargs['options'] = {}
+setup_kwargs['ext_modules'] = []
+setup_kwargs['cmdclass'] = {}
+
+#
+# py2exe options
+#
+
+if py2exe != None:
+    setup_kwargs['console'] = ['gmap.py']
+    setup_kwargs['data_files'] = [('textures', ['textures/lava.png', 'textures/water.png']),
+                                  ('', ['template.html'])]
+    setup_kwargs['zipfile'] = None
+    setup_kwargs['options']['py2exe'] = {'bundle_files' : 1}
+
+#
+# _composite.c extension
+#
+
+setup_kwargs['ext_modules'].append(Extension('_composite', ['_composite.c']))
+# tell build_ext to build the extension in-place
+# (NOT in build/)
+setup_kwargs['options']['build_ext'] = {'inplace' : 1}
+# tell the build command to only run build_ext
+build.sub_commands = [('build_ext', None)]
+
+# custom clean command to remove in-place extension
+class CustomClean(clean):
+    def run(self):
+        # do the normal cleanup
+        clean.run(self)
         
-        
+        # try to remove '_composite.{so,pyd,...}' extension,
-	)
+        # regardless of the current system's extension name convention
+        build_ext = self.get_finalized_command('build_ext')
+        fname = build_ext.get_ext_fullpath('_composite')
+        pretty_fname = os.path.split(fname)[1]
+        if os.path.exists(fname):
+            try:
+                if not self.dry_run:
+                    os.remove(fname)
+                log.info("removing '%s'", pretty_fname)
+            except OSError:
+                log.warn("'%s' could not be cleaned -- permission denied",
+                         pretty_fname)
+        else:
+            log.debug("'%s' does not exist -- can't clean it",
+                      pretty_fname)
+setup_kwargs['cmdclass']['clean'] = CustomClean
+
+###
+
+setup(**setup_kwargs)

textures.py

@@ -24,6 +24,7 @@ import numpy
 from PIL import Image, ImageEnhance
 
 import util
+import composite
 
 def _find_file(filename, mode="rb"):
     """Searches for the given file and returns an open handle to it.
@@ -157,13 +158,13 @@ def transform_image_side(img, blockID=None):
         # img to be unchanged
         mask = img.crop((0,8,16,16))
         n = Image.new(img.mode, img.size, (38,92,255,0))
-        n.paste(mask,(0,0,16,8), mask)
+        composite.alpha_over(n, mask,(0,0,16,8), mask)
         img = n
     if blockID in (78,): # snow
         # make the top three quarters transparent
         mask = img.crop((0,12,16,16))
         n = Image.new(img.mode, img.size, (38,92,255,0))
-        n.paste(mask,(0,12,16,16), mask)
+        composite.alpha_over(n, mask,(0,12,16,16), mask)
         img = n
 
     # Size of the cube side before shear
@@ -189,7 +190,7 @@ def _build_block(top, side, blockID=None):
     top = transform_image(top, blockID)
 
     if not side:
-        img.paste(top, (0,0), top)
+        composite.alpha_over(img, top, (0,0), top)
         return img
 
     side = transform_image_side(side, blockID)
@@ -212,29 +213,29 @@ def _build_block(top, side, blockID=None):
     if blockID in (37,38,6,39,40,50,83): ## flowers, sapling, mushrooms,  regular torch, reeds
         # instead of pasting these blocks at the cube edges, place them in the middle:
         # and omit the top
-        img.paste(side, (6,3), side)
+        composite.alpha_over(img, side, (6,3), side)
-        img.paste(otherside, (6,3), otherside)
+        composite.alpha_over(img, otherside, (6,3), otherside)
         return img
 
 
     if blockID in (81,): # cacti!
-        img.paste(side, (2,6), side)
+        composite.alpha_over(img, side, (2,6), side)
-        img.paste(otherside, (10,6), otherside)
+        composite.alpha_over(img, otherside, (10,6), otherside)
-        img.paste(top, (0,2), top)
+        composite.alpha_over(img, top, (0,2), top)
     elif blockID in (44,): # half step
         # shift each texture down 6 pixels
-        img.paste(side, (0,12), side)
+        composite.alpha_over(img, side, (0,12), side)
-        img.paste(otherside, (12,12), otherside)
+        composite.alpha_over(img, otherside, (12,12), otherside)
-        img.paste(top, (0,6), top)
+        composite.alpha_over(img, top, (0,6), top)
     elif blockID in (78,): # snow
         # shift each texture down 9 pixels
-        img.paste(side, (0,6), side)
+        composite.alpha_over(img, side, (0,6), side)
-        img.paste(otherside, (12,6), otherside)
+        composite.alpha_over(img, otherside, (12,6), otherside)
-        img.paste(top, (0,9), top)
+        composite.alpha_over(img, top, (0,9), top)
     else:
-        img.paste(side, (0,6), side)
+        composite.alpha_over(img, side, (0,6), side)
-        img.paste(otherside, (12,6), otherside)
+        composite.alpha_over(img, otherside, (12,6), otherside)
-        img.paste(top, (0,0), top)
+        composite.alpha_over(img, top, (0,0), top)
 
     # Manually touch up 6 pixels that leave a gap because of how the
     # shearing works out. This makes the blocks perfectly tessellate-able
@@ -366,7 +367,7 @@ def generate_special_texture(blockID, data):
             track = transform_image(raw_straight, blockID)
 
         img = Image.new("RGBA", (24,24), (38,92,255,0))
-        img.paste(track, (0,12), track)
+        composite.alpha_over(img, track, (0,12), track)
 
         return (img.convert("RGB"), img.split()[3])
     if blockID == 59: # crops
@@ -376,9 +377,9 @@ def generate_special_texture(blockID, data):
         crop3 = crop2.transpose(Image.FLIP_LEFT_RIGHT)
 
         img = Image.new("RGBA", (24,24), (38,92,255,0))
-        img.paste(crop1, (0,12), crop1)
+        composite.alpha_over(img, crop1, (0,12), crop1)
-        img.paste(crop2, (6,3), crop2)
+        composite.alpha_over(img, crop2, (6,3), crop2)
-        img.paste(crop3, (6,3), crop3)
+        composite.alpha_over(img, crop3, (6,3), crop3)
         return (img.convert("RGB"), img.split()[3])
 
     if blockID == 61: #furnace
@@ -388,9 +389,9 @@ def generate_special_texture(blockID, data):
 
         img = Image.new("RGBA", (24,24), (38,92,255,0))
 
-        img.paste(side1, (0,6), side1)
+        composite.alpha_over(img, side1, (0,6), side1)
-        img.paste(side2, (12,6), side2)
+        composite.alpha_over(img, side2, (12,6), side2)
-        img.paste(top, (0,0), top)
+        composite.alpha_over(img, top, (0,0), top)
         return (img.convert("RGB"), img.split()[3])
     
     if blockID == 62: # lit furnace
@@ -400,9 +401,9 @@ def generate_special_texture(blockID, data):
 
         img = Image.new("RGBA", (24,24), (38,92,255,0))
 
-        img.paste(side1, (0,6), side1)
+        composite.alpha_over(img, side1, (0,6), side1)
-        img.paste(side2, (12,6), side2)
+        composite.alpha_over(img, side2, (12,6), side2)
-        img.paste(top, (0,0), top)
+        composite.alpha_over(img, top, (0,0), top)
         return (img.convert("RGB"), img.split()[3])
 
     if blockID == 65: # ladder
@@ -414,22 +415,22 @@ def generate_special_texture(blockID, data):
             # have to render this thing anyway.  same for data == 2
             tex = transform_image_side(raw_texture)
             img = Image.new("RGBA", (24,24), (38,92,255,0))
-            img.paste(tex, (0,6), tex)
+            composite.alpha_over(img, tex, (0,6), tex)
             return (img.convert("RGB"), img.split()[3])
         if data == 2:
             tex = transform_image_side(raw_texture).transpose(Image.FLIP_LEFT_RIGHT)
             img = Image.new("RGBA", (24,24), (38,92,255,0))
-            img.paste(tex, (12,6), tex)
+            composite.alpha_over(img, tex, (12,6), tex)
             return (img.convert("RGB"), img.split()[3])
         if data == 3:
             tex = transform_image_side(raw_texture).transpose(Image.FLIP_LEFT_RIGHT)
             img = Image.new("RGBA", (24,24), (38,92,255,0))
-            img.paste(tex, (0,0), tex)
+            composite.alpha_over(img, tex, (0,0), tex)
             return (img.convert("RGB"), img.split()[3])
         if data == 4:
             tex = transform_image_side(raw_texture)
             img = Image.new("RGBA", (24,24), (38,92,255,0))
-            img.paste(tex, (12,0), tex)
+            composite.alpha_over(img, tex, (12,0), tex)
             return (img.convert("RGB"), img.split()[3])
             
     if blockID in (64,71): #wooden door, or iron door
@@ -450,36 +451,36 @@ def generate_special_texture(blockID, data):
         if (data & 0x03) == 0:
             if not swung:
                 tex = transform_image_side(raw_door)
-                img.paste(tex, (0,6), tex)
+                composite.alpha_over(img, tex, (0,6), tex)
             else:
                 # flip first to set the doornob on the correct side
                 tex = transform_image_side(raw_door.transpose(Image.FLIP_LEFT_RIGHT))
                 tex = tex.transpose(Image.FLIP_LEFT_RIGHT)
-                img.paste(tex, (0,0), tex)
+                composite.alpha_over(img, tex, (0,0), tex)
         
         if (data & 0x03) == 1:
             if not swung:
                 tex = transform_image_side(raw_door).transpose(Image.FLIP_LEFT_RIGHT)
-                img.paste(tex, (0,0), tex)
+                composite.alpha_over(img, tex, (0,0), tex)
             else:
                 tex = transform_image_side(raw_door)
-                img.paste(tex, (12,0), tex)
+                composite.alpha_over(img, tex, (12,0), tex)
 
         if (data & 0x03) == 2:
             if not swung:
                 tex = transform_image_side(raw_door.transpose(Image.FLIP_LEFT_RIGHT))
-                img.paste(tex, (12,0), tex)
+                composite.alpha_over(img, tex, (12,0), tex)
             else:
                 tex = transform_image_side(raw_door).transpose(Image.FLIP_LEFT_RIGHT)
-                img.paste(tex, (12,6), tex)
+                composite.alpha_over(img, tex, (12,6), tex)
 
         if (data & 0x03) == 3:
             if not swung:
                 tex = transform_image_side(raw_door.transpose(Image.FLIP_LEFT_RIGHT)).transpose(Image.FLIP_LEFT_RIGHT)
-                img.paste(tex, (12,6), tex)
+                composite.alpha_over(img, tex, (12,6), tex)
             else:
                 tex = transform_image_side(raw_door.transpose(Image.FLIP_LEFT_RIGHT))
-                img.paste(tex, (0,6), tex)
+                composite.alpha_over(img, tex, (0,6), tex)
         
         return (img.convert("RGB"), img.split()[3])