From f116221ab92a6273eb9cb589877a7177eafa2f1f Mon Sep 17 00:00:00 2001
From: Eirik Aavitsland <eirik.aavitsland@qt.io>
Date: Tue, 5 May 2020 15:25:54 +0200
Subject: [PATCH] RHI: fix off-by-one clipping

In cases where qrhi_toTopLeftRenderTargetRect() would clip the width or height
to the available space, it would subtract 1 from the result, leading to
painting errors.

Fixes: QTBUG-83928
Change-Id: I65d23151d838386b516ded0588702bc0bf4c0d93
Reviewed-by: Jonas Karlsson <jonas.karlsson@qt.io>
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>
---
 src/gui/rhi/qrhi_p_p.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/gui/rhi/qrhi_p_p.h b/src/gui/rhi/qrhi_p_p.h
index 95f04fbd1b..729b85c4d5 100644
--- a/src/gui/rhi/qrhi_p_p.h
+++ b/src/gui/rhi/qrhi_p_p.h
@@ -267,9 +267,9 @@ bool qrhi_toTopLeftRenderTargetRect(const QSize &outputSize, const std::array<T,
     *h = qMax<T>(0, inputHeight - heightOffset);
 
     if (*x + *w > outputWidth)
-        *w = qMax<T>(0, outputWidth - *x - 1);
+        *w = qMax<T>(0, outputWidth - *x);
     if (*y + *h > outputHeight)
-        *h = qMax<T>(0, outputHeight - *y - 1);
+        *h = qMax<T>(0, outputHeight - *y);
 
     return true;
 }