samples_2.4 => samples

share/grafx2/scripts/samples/picture/thomson/none_to8.lua

@@ -0,0 +1,82 @@
+-- ostro_to8.lua : convert a color image to a BM16
+-- (160x200x16) thomson image using the Ostromoukhov's
+-- error diffusion algorithm.
+--
+-- Version: 02-jan-2017
+--
+-- Copyright 2016-2017 by Samuel Devulder
+--
+-- 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/>
+
+run('lib/thomson.lua')
+run('lib/ostromoukhov.lua')
+run('lib/color_reduction.lua')
+-- run('lib/zzz.lua')
+
+-- get screen size
+local screen_w, screen_h = getpicturesize()
+
+-- Converts thomson coordinates (0-159,0-199) into screen coordinates
+local function thom2screen(x,y)
+	local i,j;
+	if screen_w/screen_h < 1.6 then
+		i = x*screen_h/200
+		j = y*screen_h/200
+	else
+		i = x*screen_w/320
+		j = y*screen_w/320
+	end
+	return math.floor(i*2), math.floor(j)
+end
+
+-- return the Color @(x,y) in normalized linear space (0-1)
+-- corresonding to the thomson screen (x in 0-319, y in 0-199)
+local function getLinearPixel(x,y)
+	local x1,y1 = thom2screen(x,y)
+	local x2,y2 = thom2screen(x+1,y+1)
+	if x2==x1 then x2=x1+1 end
+	if y2==y1 then y2=y1+1 end
+
+	local p = Color:new(0,0,0);
+	for j=y1,y2-1 do
+		for i=x1,x2-1 do
+			p:add(getLinearPictureColor(i,j))
+		end
+	end
+	p:div((y2-y1)*(x2-x1)) --:floor()
+
+	return p
+end
+
+local red = ColorReducer:new():analyzeWithDither(160,200,
+	getLinearPixel,
+    function(y)
+		thomson.info("Collecting stats...",math.floor(y/2),"%")
+	end)
+
+-- BM16 mode
+thomson.setBM16()
+
+-- define palette
+local palette = red:boostBorderColors():buildPalette(16)
+thomson.palette(0, palette)
+
+-- convert picture
+OstroDither:new(palette, 0)
+           :dither(thomson.h,thomson.w,
+             function(y,x) return getLinearPixel(x,y) end,
+			 function(y,x,c) thomson.pset(x,y,c) end,
+			 true,
+			 function(x) thomson.info("Converting...",math.floor(x*100/160),"%") end)
+
+-- refresh screen
+setpicturesize(320,200)
+thomson.updatescreen()
+finalizepicture()
+
+-- save picture
+thomson.savep()