Zoom bug fix and optimization.

Prevent drawing center from moving when client zoom size exceeds drawing size.
Prevent drawing refresh when zoom level doesn't change to eliminate flicker.

common/base_screen.cpp

@@ -69,10 +69,6 @@ void BASE_SCREEN::InitDatas()
         m_Curseur.y = ReturnPageSize().y / 2;
     }
 
-    // DrawOrg est rendu multiple du zoom min :
-    m_DrawOrg.x -= m_DrawOrg.x % 256;
-    m_DrawOrg.y -= m_DrawOrg.y % 256;
-
     m_O_Curseur = m_Curseur;
 
     SetCurItem( NULL );
@@ -230,12 +226,23 @@ void BASE_SCREEN::SetZoomList( const wxArrayInt& zoomlist )
 }
 
 
-void BASE_SCREEN::SetFirstZoom()
+bool BASE_SCREEN::SetFirstZoom()
 {
     if( m_ZoomList.IsEmpty() )
+    {
+        if( m_Zoom != m_ZoomScalar )
+        {
             m_Zoom = m_ZoomScalar;
-    else
+            return true;
+        }
+    }
+    else if( m_Zoom != m_ZoomList[0] )
+    {
         m_Zoom = m_ZoomList[0];
+        return true;
+    }
+
+    return false;
 }
 
 
@@ -245,57 +252,67 @@ int BASE_SCREEN::GetZoom() const
 }
 
 
-void BASE_SCREEN::SetZoom( int coeff )
+bool BASE_SCREEN::SetZoom( int coeff )
 {
+    if( coeff == m_Zoom )
+        return false;
+
     m_Zoom = coeff;
 
     if( m_Zoom < 1 )
         m_Zoom = 1;
+
+    return true;
 }
 
 
-void BASE_SCREEN::SetNextZoom()
+bool BASE_SCREEN::SetNextZoom()
 {
     size_t i;
 
     if( m_ZoomList.IsEmpty() || m_Zoom >= m_ZoomList.Last() )
-        return;
+        return false;
 
     for( i = 0; i < m_ZoomList.GetCount(); i++ )
     {
         if( m_Zoom < m_ZoomList[i] )
         {
             m_Zoom = m_ZoomList[i];
-            break;
+            return true;
         }
     }
+
+    return false;
 }
 
 
-void BASE_SCREEN::SetPreviousZoom()
+bool BASE_SCREEN::SetPreviousZoom()
 {
     size_t i;
 
     if( m_ZoomList.IsEmpty() || m_Zoom <= m_ZoomList[0] )
-        return;
+        return false;
 
     for( i = m_ZoomList.GetCount(); i != 0; i-- )
     {
         if( m_Zoom > m_ZoomList[i - 1] )
         {
             m_Zoom = m_ZoomList[i - 1];
-            break;
+            return true;
         }
     }
+
+    return false;
 }
 
 
-void BASE_SCREEN::SetLastZoom()
+bool BASE_SCREEN::SetLastZoom()
 {
-    if( m_ZoomList.IsEmpty() )
-        return;
+    if( m_ZoomList.IsEmpty() || m_Zoom == m_ZoomList.Last() )
+        return false;
 
     m_Zoom = m_ZoomList.Last();
+    return true;
 }
 
 

common/drawframe.cpp

@@ -584,8 +584,13 @@ void WinEDA_DrawFrame::AdjustScrollBars()
     // la surface de trace doit etre augmentee
     panel_size = DrawPanel->GetClientSize();
     screen->Unscale( panel_size );
-    draw_size += panel_size / 2;
 
+    /* Adjust drawing size when zooming way out to prevent centering around
+     * cursor problems. */
+    if( panel_size.x > draw_size.x || panel_size.y > draw_size.y )
+        draw_size = panel_size;
+
+    draw_size += panel_size / 2;
 
     if( screen->m_Center )
     {
@@ -598,10 +603,6 @@ void WinEDA_DrawFrame::AdjustScrollBars()
         screen->m_DrawOrg.y = -panel_size.y / 2;
     }
 
-    // DrawOrg est rendu multiple du zoom min :
-    screen->m_DrawOrg.x -= screen->m_DrawOrg.x % 256;
-    screen->m_DrawOrg.y -= screen->m_DrawOrg.y % 256;
-
     // Calcul du nombre de scrolls  (en unites de scrool )
     scrollbar_number = draw_size / screen->Unscale( screen->m_ZoomScalar );
     xUnit = yUnit = screen->m_ZoomScalar;

common/zoom.cpp

@@ -67,7 +67,7 @@ void WinEDA_DrawFrame::Zoom_Automatique( bool move_mouse_cursor )
 /** Redraw the screen with the zoom level which shows all the page or the board
  */
 {
-    GetBaseScreen()->SetZoom( BestZoom() );
+    if( GetBaseScreen()->SetZoom( BestZoom() )
         Recadre_Trace( move_mouse_cursor );
 }
 
@@ -122,7 +122,7 @@ void WinEDA_DrawFrame::OnZoom( wxCommandEvent& event )
     case ID_ZOOM_IN:
         if( id == ID_ZOOM_IN )
             screen->m_Curseur = DrawPanel->GetScreenCenterRealPosition();
-        screen->SetPreviousZoom();
+        if( screen->SetPreviousZoom() )
             Recadre_Trace( zoom_at_cursor );
         break;
 
@@ -133,7 +133,7 @@ void WinEDA_DrawFrame::OnZoom( wxCommandEvent& event )
     case ID_ZOOM_OUT:
         if( id == ID_ZOOM_OUT )
             screen->m_Curseur = DrawPanel->GetScreenCenterRealPosition();
-        screen->SetNextZoom();
+        if( screen->SetNextZoom() )
             Recadre_Trace( zoom_at_cursor );
         break;
 
@@ -170,7 +170,7 @@ void WinEDA_DrawFrame::OnZoom( wxCommandEvent& event )
                             "the zoom list." ), i );
             return;
         }
-        screen->SetZoom( screen->m_ZoomList[i] );
+        if( screen->SetZoom( screen->m_ZoomList[i] ) )
             Recadre_Trace( true );
     }
 

include/class_base_screen.h

@@ -228,7 +228,7 @@ public:
      * Function SetZoom
      * adjusts the current zoom factor
      */
-    void   SetZoom( int coeff );
+    bool   SetZoom( int coeff );
 
     /**
      * Function SetZoomList
@@ -246,10 +246,10 @@ public:
     void   Unscale( wxPoint& pt );
     void   Unscale( wxSize& sz );
 
-    void   SetNextZoom();                   /* ajuste le prochain coeff de zoom */
-    void   SetPreviousZoom();               /* ajuste le precedent coeff de zoom */
-    void   SetFirstZoom();                  /* ajuste le coeff de zoom a 1*/
-    void   SetLastZoom();                   /* ajuste le coeff de zoom au max */
+    bool   SetNextZoom();               /* ajuste le prochain coeff de zoom */
+    bool   SetPreviousZoom();           /* ajuste le precedent coeff de zoom */
+    bool   SetFirstZoom();              /* ajuste le coeff de zoom a 1*/
+    bool   SetLastZoom();               /* ajuste le coeff de zoom au max */
 
     //----<grid stuff>----------------------------------------------------------
     wxRealPoint GetGrid();                      /* retourne la grille */