diff -r 59a6d65fcb60 -r bdf75f0350bd hedgewars/uTextures.pas
--- a/hedgewars/uTextures.pas	Sun Jan 19 13:41:11 2014 +0100
+++ b/hedgewars/uTextures.pas	Sun Jan 19 14:58:54 2014 +0100
@@ -25,7 +25,8 @@
 function  NewTexture(width, height: Longword; buf: Pointer): PTexture;
 procedure Surface2GrayScale(surf: PSDL_Surface);
 function  Surface2Tex(surf: PSDL_Surface; enableClamp: boolean): PTexture;
-procedure PrettifySurfaceAlpha(surf: PSDL_Surface; p: PLongwordArray);
+procedure PrettifySurfaceAlpha(surf: PSDL_Surface; pixels: PLongwordArray);
+procedure PrettifyAlpha2D(pixels: TLandArray; height, width: LongWord);
 procedure FreeTexture(tex: PTexture);
 procedure FreeAndNilTexture(var tex: PTexture);
 
@@ -125,51 +126,84 @@
 { this will make invisible pixels that have a visible neighbor have the
   same color as their visible neighbor, so that bilinear filtering won't
   display a "wrongly" colored border when zoomed in }
-procedure PrettifySurfaceAlpha(surf: PSDL_Surface; p: PLongwordArray);
+procedure PrettifyAlpha(row1, row2: PLongwordArray; firsti, lasti: LongWord);
 var
-    i, lasti: Longword;
+    i: Longword;
     lpi, cpi, bpi: boolean; // was last/current/bottom neighbor pixel invisible?
 begin
-    lasti:= surf^.w * surf^.h - 1;
-    for i:=0 to lasti do
+    for i:=firsti to lasti do
         begin
-        // use first pixel in row as starting point
-        //p^[i]:= p^[i] and (BMask or GMask);
-        if (i mod surf^.w) = 0 then
-            lpi:= ((p^[i] and AMask) = 0)
+        // use first pixel in row1 as starting point
+        if i = firsti then
+            lpi:= ((row1^[i] and AMask) = 0)
         else
             begin
-            cpi:= ((p^[i] and AMask) = 0);
+            cpi:= ((row1^[i] and AMask) = 0);
             if cpi <> lpi then
                 begin
                 // invisible pixels get colors from visible neighbors
-                if (p^[i] and AMask) = 0 then
+                if (row1^[i] and AMask) = 0 then
                     begin
-                    p^[i]:= p^[i-1] and not AMask;
+                    row1^[i]:= row1^[i-1] and not AMask;
                     // as this pixel is invisible and already colored correctly now, no point in further comparing it
                     lpi:= cpi;
                     continue;
                     end
                 else
-                    p^[i-1]:= p^[i] and not AMask;
+                    row1^[i-1]:= row1^[i] and not AMask;
                 lpi:= cpi;
                 end;
             end;
         // also check bottom neighbor, lpi is now current pixel info
-        if i < lasti - surf^.w then
+        if row2 <> nil then
             begin
-            bpi:= ((p^[i + surf^.w] and AMask) = 0);
+            bpi:= ((row2^[i] and AMask) = 0);
             if cpi <> bpi then
                 begin
                 if cpi then
-                    p^[i]:= p^[i + surf^.w] and not AMask
+                    row1^[i]:= row2^[i] and not AMask
                 else
-                    p^[i + surf^.w]:= p^[i] and not AMask;
+                    row2^[i]:= row1^[i] and not AMask;
                 end;
             end;
         end;
 end;
 
+procedure PrettifySurfaceAlpha(surf: PSDL_Surface; pixels: PLongwordArray);
+var
+    // current row index, second last row index of array, width and first/last i of row
+    r, slr, w, si, li: LongWord;
+begin
+    w:= surf^.w;
+    slr:= surf^.h - 2;
+    si:= 0;
+    li:= w - 1;
+    for r:= 0 to slr do
+        begin
+        PrettifyAlpha(pixels, pixels, si, li);
+        // move indices to next row
+        si:= si + w;
+        li:= li + w;
+        end;
+    // don't forget last row
+    PrettifyAlpha(pixels, nil, si, li);
+end;
+
+procedure PrettifyAlpha2D(pixels: TLandArray; height, width: LongWord);
+var
+    // current y; last x, second last y of array;
+    y, lx, sly: LongWord;
+begin
+    sly:= height - 2;
+    lx:= width - 1;
+    for y:= 0 to sly do
+        begin
+        PrettifyAlpha(PLongWordArray(pixels[y]), PLongWordArray(pixels[y+1]), 0, lx);
+        end;
+    // don't forget last row
+    PrettifyAlpha(PLongWordArray(pixels[sly+1]), nil, 0, lx);
+end;
+
 function Surface2Tex(surf: PSDL_Surface; enableClamp: boolean): PTexture;
 var tw, th, x, y: Longword;
     tmpp: pointer;