Zero width space (#48)

* Zero width space character support via custom HTML entity &zwsp;

Author: britzl

README.md

@@ -89,7 +89,7 @@ The RichText library has limited support for HTML entities (reserved characters)
 * `>` converts into `>`
 * `&lt;` converts into `<`
 * `&nbsp;` converts into a non-breaking space between two words, ie `100&nbsp;km` becomes `100 km` with `100` and `km` acting as a single word with a space between.
-
+* `&zwsp;` converts into a zero-width space character (`\226\128\139`). This is not an official HTML entity but it is provided as a convenient way to insert one into text.
 
 # Usage
 The RichText library will create gui text nodes representing the markup in the text passed to the library. It will search for tags and split the entire text into words, where each word contains additional meta-data that is used to create and configure text nodes. This means that the library will create as many text nodes as there are words in the text.

example/example.gui_script

@@ -35,7 +35,7 @@ local function create_complex_example()
 				[hash("spineboy")] = hash("spine-spineboy"),
 			},
 		},
-		width = 410,
+		width = 460,
 		position = vmath.vector3(0, 0, 0),
 		parent = gui.get_node("bg"),
 		color = vmath.vector4(0.95, 0.95, 1.0, 1.0),
@@ -74,7 +74,7 @@ local function create_truncate_example()
 	gui.set_pivot(cursor, gui.PIVOT_NW)
 
 	local settings = { position = vmath.vector3(0, 240, 0) }
-	local words, metrics = richtext.create("This text should be shown one <img=smileys:cyclops/> at a time...", "Roboto-Regular", settings)
+	local words, metrics = richtext.create("This text should be shown one <img=smileys:cyclops/> at a time...&zwsp;&zwsp;&zwsp;&zwsp;", "Roboto-Regular", settings)
 	local length = 0
 	local max_length = #words
 	local options = { words = true }

richtext/parse.lua

@@ -4,7 +4,7 @@ local utf8 = require("richtext.utf8")
 local M = {}
 
 local function parse_tag(tag, params)
-	local settings = { tags = { [tag] = params } }
+	local settings = { tags = { [tag] = params }, tag = tag }
 	if tag == "color" then
 		settings.color = color.parse(params)
 	elseif tag == "shadow" then
@@ -38,7 +38,6 @@ local function parse_tag(tag, params)
 	elseif tag == "nobr" then
 		settings.nobr = true
 	end
-	settings.tag = tag
 
 	return settings
 end
@@ -47,10 +46,7 @@ end
 -- add a single word to the list of words
 local function add_word(text, settings, words)
 	-- handle HTML entities
-	text = text:gsub("&lt;", "<"):gsub("&gt;", ">")
-	if text:find("&nbsp;") then
-		text = text:gsub("&nbsp;", " ")
-	end
+	text = text:gsub("&lt;", "<"):gsub("&gt;", ">"):gsub("&nbsp;", " "):gsub("&zwsp;", "\226\128\139")
 
 	local data = { text = text }
 	for k,v in pairs(settings) do

richtext/richtext.lua

@@ -329,7 +329,7 @@ function M.create(text, font, settings)
 	local text_metrics = {
 		width = 0,
 		height = 0,
-		char_count = parser.length(text),
+		char_count = 0,
 	}
 	local line_words = {}
 	local line_width = 0
@@ -338,6 +338,7 @@ function M.create(text, font, settings)
 	local word_count = #words
 	for i = 1, word_count do
 		local word = words[i]
+		text_metrics.char_count = text_metrics.char_count + parser.length(word.text)
 		--print("word: [" .. word.text .. "]")
 
 		-- get font to use based on word tags