From 99804e0233cbb1054b1b1f5148dc5c7a6833a709 Mon Sep 17 00:00:00 2001
From: Vlad Zagorodniy <vladzzag@gmail.com>
Date: Thu, 9 Aug 2018 21:29:30 +0300
Subject: [PATCH] [effects/mousemark] Properly use GL_LINE_SMOOTH

Summary:
We need to enable GL_BLEND for line smoothing to work.

CCBUG: 337044

Test Plan:
Before:
{F6184072, layout=center, size=full}

After:
{F6184074, layout=center, size=full}

Reviewers: #kwin, davidedmundson

Reviewed By: #kwin, davidedmundson

Subscribers: davidedmundson, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D14714
---
 effects/mousemark/mousemark.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/effects/mousemark/mousemark.cpp b/effects/mousemark/mousemark.cpp
index f18d42f99c..25ddc0f9ad 100644
--- a/effects/mousemark/mousemark.cpp
+++ b/effects/mousemark/mousemark.cpp
@@ -119,7 +119,11 @@ void MouseMarkEffect::paintScreen(int mask, QRegion region, ScreenPaintData& dat
         return;
     if ( effects->isOpenGLCompositing()) {
         if (!GLPlatform::instance()->isGLES()) {
+            glEnable(GL_BLEND);
+            glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
             glEnable(GL_LINE_SMOOTH);
+            glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);
         }
         glLineWidth(width);
         GLVertexBuffer *vbo = GLVertexBuffer::streamingBuffer();
@@ -150,6 +154,7 @@ void MouseMarkEffect::paintScreen(int mask, QRegion region, ScreenPaintData& dat
         glLineWidth(1.0);
         if (!GLPlatform::instance()->isGLES()) {
             glDisable(GL_LINE_SMOOTH);
+            glDisable(GL_BLEND);
         }
     }
 #ifdef KWIN_HAVE_XRENDER_COMPOSITING