Add Tiler, a factory script that extracts (unique) tiles from spare to main page.

git-svn-id: svn://pulkomandy.tk/GrafX2/trunk@1823 416bcca6-2ee7-4201-b75f-2eb2f807beb1

share/grafx2/scripts/samples_2.4/picture/Tiler.lua

@@ -0,0 +1,119 @@
+--PICTURE: Tiler
+--By Adrien Destugues
+--
+--Extract unique tiles from the spare page to the main one
+--Main page is erased.
+--
+-- Copyright 2010 Adrien Destugues <pulkomandy@pulkomandy.ath.cx>
+--
+-- This program 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; version 2
+-- of the License. See <http://www.gnu.org/licenses/>
+
+-- Copy palette from spare to main
+-- TODO
+
+-- Grid size
+-- TODO : get it from GrafX2
+xgrid = 8
+ygrid = 16
+
+-- picture size
+w, h = getsparepicturesize()
+
+-- We may need less if there are duplicates
+setpicturesize(xgrid, w*h/xgrid)
+
+tileid = 0
+
+-- blit part of the spare to picture
+function blitsparetopicture(srcx, srcy, dstx, dsty, width, height)
+	local x,y,color
+	for y = 0, height - 1, 1 do
+		for x = 0, width - 1, 1 do
+			color = getsparepicturepixel(srcx + x, srcy + y);
+			putpicturepixel(dstx+x, dsty+y, color);
+		end
+	end
+end
+
+function comparesparetopicture(srcx, srcy, dstx, dsty, width, height)
+	local x,y,color
+	for y = 0, height - 1, 1 do
+		for x = 0, width - 1, 1 do
+			color = getsparepicturepixel(srcx + x, srcy + y);
+			if color ~= getpicturepixel(dstx+x, dsty+y) then
+				-- they are different
+				return false;
+			end
+		end
+	end
+	-- they are identical
+	return true;
+end
+
+-- compute checksum of a picture area
+-- it may not be unique, we use it as a key for an hashmap
+function checksum(srcx, srcy, width, height)
+	local sum,x,y
+	sum = 0;
+	for y = 0, height - 1, 1 do
+		for x = 0, width - 1, 1 do
+			sum = sum + getsparepicturepixel(srcx+x, srcy+y);
+		end
+	end
+
+	return sum;
+end
+
+tilemap = {}
+
+-- foreach tile
+for y = 0, h-1, ygrid do
+	for x = 0, w - 1, xgrid do
+		--TODO - existing one ?
+		csum = checksum(x,y,xgrid,ygrid);
+		if tilemap[csum] ~= nil then
+			-- potential match
+			-- Find matching tileid
+			found = false;
+			for id in pairs(tilemap[csum]) do
+				-- is it a match ?
+				if comparesparetopicture(x,y,0,id*ygrid, xgrid, ygrid) then
+					-- found it !
+					tilemap[csum][id] = tilemap[csum][id] + 1;
+					found = true;
+					break;
+				end
+			end
+			-- Add tile anyway if needed
+			if not found then
+				desty = tileid * ygrid;
+				blitsparetopicture(x, y, 0, desty, xgrid, ygrid);
+
+				-- add it to the tilemap
+				tilemap[csum][tileid] = 1;
+				-- give it a tile id
+				tileid = tileid + 1;
+			end
+		else
+			-- Copy to spare
+			desty = tileid * ygrid;
+			blitsparetopicture(x, y, 0, desty, xgrid, ygrid);
+
+			-- add it to the tilemap
+			tilemap[csum] = {}
+			tilemap[csum][tileid] = 1;
+			-- give it a tile id
+			tileid = tileid + 1;
+		end
+		--statusmessage("processed " .. tileid .. " tiles");
+		--updatescreen();
+	end
+end
+
+setpicturesize(xgrid, (tileid-1)*ygrid)
+
+finalizepicture()
+updatescreen()