From b738d5933db85e33f1ea51e1ace44d52a9aaa613 Mon Sep 17 00:00:00 2001
From: Mathieu Duponchelle <mathieu@centricular.com>
Date: Sat, 13 Nov 2021 00:16:51 +0100
Subject: [PATCH] tttojson: fix row computation

I hadn't really tested the element with pop-on mode, and the row
for each line in the input text was hardcoded to 13, which was
clearly wrong.

Switch to incrementing it properly.
---
 video/closedcaption/src/tttojson/imp.rs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/video/closedcaption/src/tttojson/imp.rs b/video/closedcaption/src/tttojson/imp.rs
index be6bd46cd..9eda203e9 100644
--- a/video/closedcaption/src/tttojson/imp.rs
+++ b/video/closedcaption/src/tttojson/imp.rs
@@ -22,6 +22,7 @@ use gst::subclass::prelude::*;
 
 use once_cell::sync::Lazy;
 
+use std::cmp::min;
 use std::sync::Mutex;
 
 use crate::ttutils::{Cea608Mode, Chunk, Line, Lines, TextStyle};
@@ -91,11 +92,13 @@ impl TtToJson {
             clear: Some(false),
         };
 
+        let mut row = min(15usize.saturating_sub(text.lines().count()), 13usize) as u32;
+
         for phrase in text.lines() {
             lines.lines.push(Line {
                 carriage_return: Some(true),
                 column: Some(0),
-                row: Some(13),
+                row: Some(row),
                 chunks: vec![Chunk {
                     // Default CEA 608 styling
                     style: TextStyle::White,
@@ -103,6 +106,8 @@ impl TtToJson {
                     text: phrase.to_string(),
                 }],
             });
+
+            row = min(14u32, row + 1);
         }
 
         let json = serde_json::to_string(&lines).map_err(|err| {