From 6ee7e51af360b3c7479e31df989b78bd69a8e606 Mon Sep 17 00:00:00 2001 From: James Turner Date: Fri, 27 Nov 2015 23:25:11 +0000 Subject: [PATCH] Clamp diagram zoom. - avoid poor performance and unusable UI when zooming out --- src/GUI/BaseDiagram.cxx | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/src/GUI/BaseDiagram.cxx b/src/GUI/BaseDiagram.cxx index 4204626e5..fa593f8b7 100644 --- a/src/GUI/BaseDiagram.cxx +++ b/src/GUI/BaseDiagram.cxx @@ -38,6 +38,8 @@ const float rec = 6378137; // earth radius, equator (?) const float rpol = 6356752.314f; // earth radius, polar (?) +const double MINIMUM_SCALE = 0.002; + //Returns Earth radius at a given latitude (Ellipsoide equation with two equal axis) static float earth_radius_lat( float lat ) { @@ -547,12 +549,16 @@ void BaseDiagram::wheelEvent(QWheelEvent *we) m_wheelAngleDeltaAccumulator += delta; if (m_wheelAngleDeltaAccumulator > 120) { m_wheelAngleDeltaAccumulator = 0; - m_scale *= 2.0; + + m_scale *= 1.5; + } else if (m_wheelAngleDeltaAccumulator < -120) { m_wheelAngleDeltaAccumulator = 0; - m_scale *= 0.5; + + m_scale *= 0.75; } + SG_CLAMP_RANGE(m_scale, MINIMUM_SCALE, 1.0); update(); } -- 2.39.5