Make "vertlabel[]" formspec element support core.colorize

[CrazyladMT]

Fixes #14426

This PR adds support for core.colorize in the vertlabel[] formspec element by using EnrichedString to preserve newlines and color escapes.

There are also some minor code style fixes applied throughout guiFormSpecMenu.cpp, as shown in the commit.

To do

This PR is Ready for Review.

How to test

1. make a mod with the following code:

core.register_on_joinplayer(function(player)
   local name = player:get_player_name()

   local fs = table.concat({
       "formspec_version[6]",
       "size[8,8]",
       "vertlabel[1,0;",
           core.colorize("#FF0000", " Red\ntext"),
       "]",
   })

   core.show_formspec(name, "test:vertlabel", fs)
end)

2. enable the mod and join any world
3. observe that vertlabel[] now colorizes text

[sfan5]

my changes:

diff --git a/src/gui/guiFormSpecMenu.cpp b/src/gui/guiFormSpecMenu.cpp
index 3bcc955b4..787d6c006 100644
--- a/src/gui/guiFormSpecMenu.cpp
+++ b/src/gui/guiFormSpecMenu.cpp
@@ -1887,13 +1887,10 @@ void GUIFormSpecMenu::parseVertLabel(parserData* data, const std::string &elemen
 	// Use EnrichedString so color escapes and formatting are preserved
 	EnrichedString etext(unescape_string(utf8_to_wide(parts[1])));
 
-	// Build vertical enriched text (one character per line)
+	// Build vertical text (one character per line)
 	EnrichedString vlabel;
 	const size_t char_count = etext.getString().size();
-	const size_t line_count = char_count + 1;  // account for dummy line
-
-	// Dummy first line to avoid clipping
-	vlabel.addCharNoColor(L'\n');
+	const size_t line_count = char_count;
 
 	for (size_t i = 0; i < char_count; i++) {
 		vlabel += etext.substr(i, 1);
@@ -1916,12 +1913,9 @@ void GUIFormSpecMenu::parseVertLabel(parserData* data, const std::string &elemen
 		// Vertlabels are positioned by center, not left.
 		pos.X -= imgsize.X / 2;
 
-		// We use the character count + 1 because without it, the rect
-		// isn't quite tall enough and cuts off the text.
 		rect = core::rect<s32>(pos.X, pos.Y,
 			pos.X + imgsize.X,
-			pos.Y + font_line_height(font) *
-			(etext.getString().size() + 1));
+			pos.Y + font_line_height(font) * char_count);
 
 	} else {
 		pos = getElementBasePos(&v_pos);

here's the results (vertlabel and label at exactly the same place):

this looks much more correct to me than introducing some random offset

[sfan5]

ok

[CrazyladMT]

this looks much more correct to me than introducing some random offset

Thanks for the help. I agree, it does look correct now. I must have been confused about the difference between real coordinates and the old formspec system.

Using "real_coordinates[true]" with "vertlabel[0.15,0;" .. core.colorize("#FF0000", " Red\ntext") .. "]",:

This looks correct.
However, with "real_coordinates[false]":

Apparently this offset existed even before my changes, unless I am missing something.
I do find it strange that inputting 0 as the Y value for the vertlabel formspec element makes the label... not be at Y = 0. I'm not exactly sure how to fix this. Is this the desired behavior?

[sfan5]

Is this the desired behavior?

with real_coordinates disabled: sure.