From a3e106509657349d6dc44a7a7d520da1e9c2e412 Mon Sep 17 00:00:00 2001
From: Uwe Rathmann <Uwe.Rathmann@tigertal.de>
Date: Wed, 29 Dec 2021 15:30:44 +0100
Subject: [PATCH] QRectF interpolator added

---
 src/common/QskFunctions.cpp | 16 ++++++++++++++++
 src/common/QskFunctions.h   |  3 +++
 2 files changed, 19 insertions(+)

diff --git a/src/common/QskFunctions.cpp b/src/common/QskFunctions.cpp
index a0c1f2ca..c084a433 100644
--- a/src/common/QskFunctions.cpp
+++ b/src/common/QskFunctions.cpp
@@ -122,6 +122,22 @@ QRectF qskValidOrEmptyInnerRect( const QRectF& rect, const QMarginsF& margins )
     return QRectF( x, y, w, h );
 }
 
+QRectF qskInterpolatedRect( const QRectF &from, const QRectF &to, qreal progress )
+{
+    if ( progress <= 0.0 )
+        return from;
+
+    if ( progress >= 1.0 )
+        return to;
+
+    const auto x = from.x() + progress * ( to.x() - from.x() );
+    const auto y = from.y() + progress * ( to.y() - from.y() );
+    const auto w = from.width() + progress * ( to.width() - from.width() );
+    const auto h = from.height() + progress * ( to.height() - from.height() );
+
+    return QRectF( x, y, w, h );
+}
+
 qreal qskHorizontalAdvance( const QFont& font, const QString& text )
 {
     return qskHorizontalAdvance( QFontMetricsF( font ), text );
diff --git a/src/common/QskFunctions.h b/src/common/QskFunctions.h
index 2855a2be..765960a5 100644
--- a/src/common/QskFunctions.h
+++ b/src/common/QskFunctions.h
@@ -30,6 +30,9 @@ QSK_EXPORT QRectF qskValidOrEmptyInnerRect(
 QSK_EXPORT qreal qskHorizontalAdvance( const QFont&, const QString& );
 QSK_EXPORT qreal qskHorizontalAdvance( const QFontMetricsF&, const QString& );
 
+QSK_EXPORT QRectF qskInterpolatedRect(
+    const QRectF& from, const QRectF& to, qreal progress );
+
 inline QMarginsF qskMargins( const QRectF& rect, const QRectF& innerRect )
 {
     return QMarginsF(