improved scrolling (at least for formspec version 3)

exec_actions.lua

@@ -670,7 +670,7 @@ yl_speak_up.get_fs_action_text_input = function(player, param)
 
 	-- do not offer edit_mode in the trade formspec because it makes no sense there;
 	return yl_speak_up.show_fs_decorated(pname, nil, h, alternate_text, "",
-		table.concat(formspec, "\n"), nil)
+		table.concat(formspec, "\n"), nil, h)
 
 --[[ old version with extra formspec
 	return --"size[12.0,4.5]"..

fs_decorated.lua

@@ -21,8 +21,8 @@ minetest.register_chatcommand( 'npc_talk_style', {
 			minetest.chat_send_player(pname, "This command sets your formspec version "..
 				"for the yl_speak_up NPC to value <version>.\n"..
 				"  Version 1: For very old clients. Not recommended.\n"..
-				"  Version 2: Adds extra scroll buttons. Perhaps you like this more.\n"..
-				"  Version 3: Default version.")
+				"  Version 2: Adds extra scroll buttons.\n"..
+				"  Version 3: Default (recommended) version.")
 		end
 		minetest.chat_send_player(pname, "Your formspec version for the yl_speak_up NPC "..
 			"has been set to version "..tostring(yl_speak_up.fs_version[pname])..
@@ -148,7 +148,8 @@ yl_speak_up.show_fs_decorated = function(pname, edit_mode, h,
 					alternate_text,
 					add_this_to_left_window,
 					add_this_to_bottom_window,
-					active_dialog)
+					active_dialog,
+					h)
 	if(not(pname)) then
 		return ""
 	end
@@ -260,11 +261,23 @@ yl_speak_up.show_fs_decorated = function(pname, edit_mode, h,
 	table.insert(formspec, add_this_to_left_window)
 
 	local pname_for_old_fs = nil
-	if(fs_version > 2) then
-	        table.insert(formspec, "scrollbaroptions[min=0;max=14;smallstep=1;largestep=2;arrows=show]")
+
+	-- is there any need to allow scrolling?
+	local allow_scrolling = true
+	-- in case of older formspec versions: it already does look pretty ugly; there
+	-- is no point in checking there if we can scroll or not
+	if(fs_version > 2 and h + 1 < yl_speak_up.max_number_of_buttons) then
+		allow_scrolling = false
+	end
+
+	if(allow_scrolling and fs_version > 2) then
+		local max_scroll = math.ceil(h - yl_speak_up.max_number_of_buttons) + 1
+	        table.insert(formspec, "scrollbaroptions[min=0;max="..tostring(max_scroll)..
+					";smallstep=1;largestep=2;arrows=show".. --]")
+					";thumbsize="..tostring(math.ceil(h/yl_speak_up.max_number_of_buttons)).."]")
 	        table.insert(formspec, "scrollbar[0.2,24.2;0.2,7;vertical;scr0;0]")
 	        table.insert(formspec, "scroll_container[0,24;56,7;scr0;vertical;1]")
-	else
+	elseif(allow_scrolling) then
 		if(fs_version < 2) then
 			-- if the player has an older formspec version
 			minetest.log( "info",
@@ -292,6 +305,8 @@ yl_speak_up.show_fs_decorated = function(pname, edit_mode, h,
 			table.insert(formspec, "button[53.5,0;1,3;button_down;^\nU\np]")
 			table.insert(formspec, "button[53.5,3.2;1,4.5;button_up;D\no\nw\nn\nv]")
 		end
+	else
+		table.insert(formspec, "container[0,24]")
 	end
 
 	table.insert(formspec, add_this_to_bottom_window)
@@ -302,7 +317,7 @@ yl_speak_up.show_fs_decorated = function(pname, edit_mode, h,
 		yl_speak_up.message_button_option_exit,
 		true, nil, true, pname_for_old_fs) -- button_exit
 
-	if(fs_version > 2) then
+	if(allow_scrolling and fs_version > 2) then
 		table.insert(formspec, "scroll_container_end[]")
 	else
 	        table.insert(formspec, "container_end[]")

fs_talkdialog.lua

@@ -741,5 +741,5 @@ yl_speak_up.get_fs_talkdialog = function(player, n_id, d_id, alternate_text, rec
 
 	return yl_speak_up.show_fs_decorated(pname, edit_mode, h, alternate_text,
 	                                        left_window_fs, bottom_window_fs,
-						active_dialog)
+						active_dialog, h)
 end

trade_list.lua

@@ -209,7 +209,7 @@ yl_speak_up.get_fs_trade_list = function(player, show_dialog_option_trades)
 			"label[1,1;Sorry. There are currently no offers available.]")
 	end
 
-	-- kein edit_mode beim trade-formspec da nicht sinnvoll
+	-- edit mode makes no sense here in the trade list
 	return yl_speak_up.show_fs_decorated(pname, nil, h, alternate_text, "",
-                                        table.concat(formspec, "\n"), nil)
+                                        table.concat(formspec, "\n"), nil, h)
 end