From e487e96954c0d171700daa4fd967588f15e10b9c Mon Sep 17 00:00:00 2001
From: nirvn <nirvn.asia@gmail.com>
Date: Thu, 15 Aug 2019 09:51:57 +0700
Subject: [PATCH] [labeling] Prohibit non horizontal orientation for curved
 placement

---
 src/core/qgspallabeling.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/core/qgspallabeling.cpp b/src/core/qgspallabeling.cpp
index ff6ff62af728..02fe2105abf5 100644
--- a/src/core/qgspallabeling.cpp
+++ b/src/core/qgspallabeling.cpp
@@ -545,6 +545,13 @@ void QgsPalLayerSettings::startRender( QgsRenderContext &context )
     return;
   }
 
+  if ( placement == QgsPalLayerSettings::Curved )
+  {
+    // force horizontal orientation, other orientation modes aren't unsupported for curved placement
+    mFormat.setOrientation( QgsTextFormat::HorizontalOrientation );
+    mDataDefinedProperties.property( QgsPalLayerSettings::TextOrientation ).setActive( false );
+  }
+
   if ( mCallout )
   {
     mCallout->startRender( context );