From d6528d84a9d650015630defaf59041ea5e76e84f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89milie=20Feral?= <emilie.feral@numworks.com>
Date: Fri, 9 Jun 2017 11:35:53 +0200
Subject: [PATCH] [apps/shared] Change zoom to ensure to keep the same cusor
 position

Change-Id: Ie24fcdda2aad7da8872915511fcd2e71d19ff8a6
---
 .../interactive_curve_view_controller.cpp     |  8 ++------
 apps/shared/interactive_curve_view_range.cpp  | 20 +++++++++----------
 apps/shared/interactive_curve_view_range.h    |  2 +-
 apps/shared/zoom_parameter_controller.cpp     |  8 ++++++--
 4 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/apps/shared/interactive_curve_view_controller.cpp b/apps/shared/interactive_curve_view_controller.cpp
index 9c3b3b606..25181ade5 100644
--- a/apps/shared/interactive_curve_view_controller.cpp
+++ b/apps/shared/interactive_curve_view_controller.cpp
@@ -60,16 +60,12 @@ bool InteractiveCurveViewController::handleEvent(Ion::Events::Event event) {
     return false;
   }
   if (event == Ion::Events::Plus) {
-    interactiveCurveViewRange()->zoom(1.0f/3.0f);
-    initCursorParameters();
-    reloadBannerView();
+    interactiveCurveViewRange()->zoom(2.0f/3.0f, m_cursor->x(), m_cursor->y());
     curveView()->reload();
     return true;
   }
   if (event == Ion::Events::Minus) {
-    interactiveCurveViewRange()->zoom(3.0f/4.0f);
-    initCursorParameters();
-    reloadBannerView();
+    interactiveCurveViewRange()->zoom(3.0f/2.0f, m_cursor->x(), m_cursor->y());
     curveView()->reload();
     return true;
   }
diff --git a/apps/shared/interactive_curve_view_range.cpp b/apps/shared/interactive_curve_view_range.cpp
index 9eb8b9f6b..c0da85988 100644
--- a/apps/shared/interactive_curve_view_range.cpp
+++ b/apps/shared/interactive_curve_view_range.cpp
@@ -85,26 +85,26 @@ void InteractiveCurveViewRange::setYAuto(bool yAuto) {
   }
 }
 
-void InteractiveCurveViewRange::zoom(float ratio) {
+void InteractiveCurveViewRange::zoom(float ratio, float x, float y) {
   float xMin = m_xMin;
   float xMax = m_xMax;
   float yMin = m_yMin;
   float yMax = m_yMax;
-  if (2.0f*ratio*fabsf(xMax-xMin) < k_minFloat || 2.0f*ratio*fabsf(yMax-yMin) < k_minFloat) {
+  if (ratio*fabsf(xMax-xMin) < k_minFloat || ratio*fabsf(yMax-yMin) < k_minFloat) {
     return;
   }
-  float newXMin = clipped((xMax+xMin)/2.0f - ratio*fabsf(xMax-xMin), false);
-  float newXMax = clipped((xMax+xMin)/2.0f + ratio*fabsf(xMax-xMin), true);
+  float newXMin = clipped(x*(1.0f-ratio)+ratio*xMin, false);
+  float newXMax = clipped(x*(1.0f-ratio)+ratio*xMax, true);
   if (!isnan(newXMin) && !isnan(newXMax)) {
-    m_xMax = clipped((xMax+xMin)/2.0f + ratio*fabsf(xMax-xMin), true);
-    MemoizedCurveViewRange::setXMin(clipped((xMax+xMin)/2.0f - ratio*fabsf(xMax-xMin), false));
+    m_xMax = newXMax;
+    MemoizedCurveViewRange::setXMin(newXMin);
   }
   m_yAuto = false;
-  float newYMin = clipped((yMax+yMin)/2.0f - ratio*fabsf(yMax-yMin), false);
-  float newYMax = clipped((yMax+yMin)/2.0f + ratio*fabsf(yMax-yMin), true);
+  float newYMin = clipped(y*(1.0f-ratio)+ratio*yMin, false);
+  float newYMax = clipped(y*(1.0f-ratio)+ratio*yMax, true);
   if (!isnan(newYMin) && !isnan(newYMax)) {
-    m_yMax = clipped((yMax+yMin)/2.0f + ratio*fabsf(yMax-yMin), true);
-    MemoizedCurveViewRange::setYMin(clipped((yMax+yMin)/2.0f - ratio*fabsf(yMax-yMin), false));
+    m_yMax = newYMax;
+    MemoizedCurveViewRange::setYMin(newYMin);
   }
 }
 
diff --git a/apps/shared/interactive_curve_view_range.h b/apps/shared/interactive_curve_view_range.h
index 5aa57871e..afe7b6c21 100644
--- a/apps/shared/interactive_curve_view_range.h
+++ b/apps/shared/interactive_curve_view_range.h
@@ -24,7 +24,7 @@ public:
   void setYAuto(bool yAuto);
 
   // Window
-  void zoom(float ratio);
+  void zoom(float ratio, float x, float y);
   void panWithVector(float x, float y);
   virtual void roundAbscissa();
   virtual void normalize();
diff --git a/apps/shared/zoom_parameter_controller.cpp b/apps/shared/zoom_parameter_controller.cpp
index bb2f8bf63..761930834 100644
--- a/apps/shared/zoom_parameter_controller.cpp
+++ b/apps/shared/zoom_parameter_controller.cpp
@@ -21,12 +21,16 @@ View * ZoomParameterController::view() {
 
 bool ZoomParameterController::handleEvent(Ion::Events::Event event) {
   if (event == Ion::Events::Plus) {
-    m_interactiveRange->zoom(1.0f/3.0f);
+    float meanX = (m_interactiveRange->xMin()+m_interactiveRange->xMax())/2.0f;
+    float meanY = (m_interactiveRange->yMin()+m_interactiveRange->yMax())/2.0f;
+    m_interactiveRange->zoom(2.0f/3.0f, meanX, meanY);
     m_contentView.curveView()->reload();
     return true;
   }
   if (event == Ion::Events::Minus) {
-    m_interactiveRange->zoom(3.0f/4.0f);
+    float meanX = (m_interactiveRange->xMin()+m_interactiveRange->xMax())/2.0f;
+    float meanY = (m_interactiveRange->yMin()+m_interactiveRange->yMax())/2.0f;
+    m_interactiveRange->zoom(3.0f/2.0f, meanX, meanY);
     m_contentView.curveView()->reload();
     return true;
   }