From: Carl Hetherington <cth@carlh.net>
Date: Sat, 26 Aug 2023 17:51:51 +0000 (+0200)
Subject: Fix incorrect horizontal positions when different HPositions are used with one VPosition.
X-Git-Tag: v2.16.63~6
X-Git-Url: https://git.carlh.net/gitweb/?a=commitdiff_plain;h=a2507e28a631ee68b0ba898b4fc0c22bbaa2eef2;p=dcpomatic.git

Fix incorrect horizontal positions when different HPositions are used with one VPosition.

Previously if HPosition changed we would still use a single "line" (i.e. Pango layout)
for all the text, meaning that HPosition would not be respected.
---

diff --git a/src/lib/render_text.cc b/src/lib/render_text.cc
index 84fc8414d..ddfccbde8 100644
--- a/src/lib/render_text.cc
+++ b/src/lib/render_text.cc
@@ -408,9 +408,15 @@ render_text(vector<StringText> subtitles, dcp::Size target, DCPTime time, int fr
 	vector<PositionImage> images;
 
 	for (auto const& i: subtitles) {
-		if (!pending.empty() && (i.v_align() != pending.back().v_align() || fabs(i.v_position() - pending.back().v_position()) > 1e-4)) {
-			images.push_back(render_line(pending, target, time, frame_rate));
-			pending.clear ();
+		if (!pending.empty()) {
+			auto const last = pending.back();
+			auto const different_v = i.v_align() != last.v_align() || fabs(i.v_position() - last.v_position()) > 1e-4;
+			auto const different_h = i.h_align() != last.h_align() || fabs(i.h_position() - pending.back().h_position()) > 1e-4;
+			if (different_v || different_h) {
+				/* We need a new line if any new positioning (horizontal or vertical) changes for this section */
+				images.push_back(render_line(pending, target, time, frame_rate));
+				pending.clear ();
+			}
 		}
 		pending.push_back (i);
 	}