1 files changed, 217 insertions, 0 deletions
diff --git a/signs/common.lua b/signs/common.lua
new file mode 100644
index 0000000..0433223
--- /dev/null
+++ b/signs/common.lua
@@ -0,0 +1,217 @@
+local font = {}
+signs.font_height = 10
+
+-- Get png width, suposing png width is less than 256 (it is the case for all font textures)
+local function get_png_width(filename)
+	local file=assert(io.open(filename,"rb"))
+	-- All font png are smaller than 256x256 --> read only last byte
+	file:seek("set",19)
+	local w = file:read(1)
+	file:close()
+	return w:byte()
+end
+
+-- Computes line width for a given font height and text
+function signs.get_line_width(text)
+	local char
+	local width = 0
+
+	for p=1,#text
+	do
+		char = text:sub(p,p):byte()
+		if font[char] then
+			width = width + font[char].width
+		end
+	end
+
+	return width
+end
+
+--- Builds texture part for a text line
+-- @param text Text to be rendered
+-- @param x Starting x position in texture
+-- @param width Width of the texture (extra text is not rendered)
+-- @param y Vertical position of the line in texture
+-- @return Texture string
+function signs.make_line_texture(text, x, width, y)
+	local char
+
+	local texture = ""
+
+	for p=1,#text
+	do
+		char = text:sub(p,p):byte()
+		if font[char] then
+			-- Add image only if it is visible (at least partly)
+			if x + font[char].width >= 0 and x <= width then
+				texture = texture..string.format(":%d,%d=%s", x, y, font[char].filename)
+			end
+			x = x + font[char].width
+		end
+	end
+	return texture
+end
+
+local function split_lines(text, maxlines)
+	local splits = text:split("\n")
+	if maxlines then
+		local lines = {}
+		for num = 1,maxlines do
+			lines[num] = splits[num]
+		end
+		return lines
+	else
+		return splits
+	end
+end
+
+function signs.on_display_update(pos, objref)
+	local meta = minetest.get_meta(pos)
+	local text = meta:get_string("display_text")
+
+	local ndef = minetest.registered_nodes[minetest.get_node(pos).name]
+	if ndef and ndef.sign_model then
+		local model = signs.sign_models[ndef.sign_model]
+		local lines = split_lines(text, model.maxlines)
+
+		local texturew = model.width/model.xscale
+		local textureh = model.height/model.yscale
+
+		local texture = ""
+
+		local y
+		if model.valing == "top" then
+			y = signs.font_height / 2
+		else		
+			y = (textureh - signs.font_height * #lines) / 2 + 1 
+		end
+
+		for _, line in pairs(lines) do
+			texture = texture..signs.make_line_texture(line, 
+				(texturew - signs.get_line_width(line)) / 2, 
+				texturew, y)
+			y = y + signs.font_height
+		end
+
+		local texture = string.format("[combine:%dx%d", texturew, textureh)..texture
+		if model.color then texture = texture.."^[colorize:"..model.color end
+
+		objref:set_properties({ textures={texture}, visual_size = {x=model.width, y=model.height}})
+	end
+end
+
+function signs.set_formspec(pos)
+	local meta = minetest.get_meta(pos)
+	local ndef = minetest.registered_nodes[minetest.get_node(pos).name]
+	if ndef and ndef.sign_model then
+		local model = signs.sign_models[ndef.sign_model]
+		local formspec
+
+		if model.maxlines == 1 then
+			formspec = "size[6,3]"..
+				"field[0.5,0.7;5.5,1;display_text;Displayed text;${display_text}]"..
+				"button_exit[2,2;2,1;ok;Write]"
+		else
+			local extralabel = ""
+			if model.maxlines then
+				extralabel = " (first "..model.maxlines.." lines only)"
+			end
+
+			formspec = "size[6,4]"..
+				"textarea[0.5,0.7;5.5,2;display_text;Displayed text"..extralabel..";${display_text}]"..
+				"button_exit[2,3;2,1;ok;Write]"
+		end
+
+		meta:set_string("formspec", formspec)
+	end
+end
+
+function signs.on_receive_fields(pos, formname, fields, player)
+	if not minetest.is_protected(pos, player:get_player_name()) then
+		local meta = minetest.get_meta(pos)
+		if fields and fields.ok then
+			meta:set_string("display_text", fields.display_text)
+			meta:set_string("infotext", "\""..fields.display_text.."\"")
+			display_lib.update_entities(pos)
+		end
+	end
+end
+
+-- On place callback for direction signs 
+-- (chooses which sign according to look direction)
+function signs.on_place_direction(itemstack, placer, pointed_thing)
+	local above = pointed_thing.above
+	local under = pointed_thing.under
+	local wdir = minetest.dir_to_wallmounted(
+				{x = under.x - above.x,
+				 y = under.y - above.y,
+				 z = under.z - above.z})
+	
+	local dir = placer:get_look_dir()
+
+	if wdir == 0 or wdir == 1 then
+		wdir = minetest.dir_to_wallmounted({x=dir.x, y=0, z=dir.z})
+	end
+
+	local name = itemstack:get_name()
+
+	-- Only for direction signs (ending with _right)
+	if name:sub(-string.len("_right")) == "_right" then
+		name = name:sub(1, -string.len("_right"))
+
+		local test = {0, dir.z, -dir.z, -dir.x, dir.x}
+		if test[wdir] > 0 then
+			itemstack:set_name(name.."left")
+		end
+		itemstack = minetest.item_place(itemstack, placer, pointed_thing, wdir)
+		itemstack:set_name(name.."right")
+
+		return itemstack
+	else
+		return minetest.item_place(itemstack, placer, pointed_thing, wdir)
+	end
+end
+
+-- On_rotate (screwdriver) callback for direction signs
+function signs.on_rotate_direction(pos, node, user, mode, new_param2)
+	if mode == screwdriver.ROTATE_AXIS then 
+		local name
+		if node.name:sub(-string.len("_right")) == "_right" then
+			name = node.name:sub(1, -string.len("_right")).."left"
+		end
+		if node.name:sub(-string.len("_left")) == "_left" then
+			name = node.name:sub(1, -string.len("_left")).."right"
+		end
+
+		if name then
+			minetest.swap_node(pos, {name = name, param1 = node.param1, param2 = node.param2})
+		end
+		return false
+	else
+		return display_lib.on_rotate(pos, node, user, mode, new_param2)
+	end
+end
+
+-- Populate fonts table
+local w, filename
+for charnum=32,126 do
+	filename = string.format("signs_%02x.png", charnum)
+	w = get_png_width(signs.path.."/textures/"..filename)
+	font[charnum] = {filename=filename, width=w}
+end
+
+-- Generic callback for show_formspec displayed formspecs
+minetest.register_on_player_receive_fields(function(player, formname, fields)
+	local found, mod, node_name, pos
+	found, _, mod, node_name, pos = formname:find("([%w_]+):([%w_]+)@(.+)")
+
+	if found then
+		if mod ~= 'signs' then return end
+
+		local ndef = minetest.registered_nodes[mod..":"..node_name]
+
+		if ndef and ndef.on_receive_fields then
+			ndef.on_receive_fields(minetest.string_to_pos(pos), formname, fields, player)
+		end
+	end
+end)