Fixes, properly handle TV format any ystart changes from GUI.

src/emucore/Console.cxx

@@ -216,7 +216,7 @@ Console::~Console()
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-void Console::autodetectFrameLayout()
+void Console::autodetectFrameLayout(bool reset)
 {
   // Run the TIA, looking for PAL scanline patterns
   // We turn off the SuperCharger progress bars, otherwise the SC BIOS
@@ -227,7 +227,8 @@ void Console::autodetectFrameLayout()
 
   FrameLayoutDetector frameLayoutDetector;
   myTIA->setFrameManager(&frameLayoutDetector);
-  mySystem->reset(true);
+
+  if (reset) mySystem->reset(true);
 
   for(int i = 0; i < 60; ++i) myTIA->update();
 
@@ -247,7 +248,7 @@ void Console::redetectFrameLayout()
   myOSystem.sound().close();
   save(s);
 
-  autodetectFrameLayout();
+  autodetectFrameLayout(false);
   if (myYStartAutodetected) autodetectYStart();
 
   load(s);
@@ -255,7 +256,7 @@ void Console::redetectFrameLayout()
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-void Console::autodetectYStart()
+void Console::autodetectYStart(bool reset)
 {
   // We turn off the SuperCharger progress bars, otherwise the SC BIOS
   // will take over 250 frames!
@@ -266,7 +267,8 @@ void Console::autodetectYStart()
   YStartDetector ystartDetector;
   ystartDetector.setLayout(myDisplayFormat == "PAL" ? FrameLayout::pal : FrameLayout::ntsc);
   myTIA->setFrameManager(&ystartDetector);
-  mySystem->reset(true);
+
+  if (reset) mySystem->reset(true);
 
   for (int i = 0; i < 80; i++) myTIA->update();
 
@@ -288,7 +290,7 @@ void Console::redetectYStart()
   myOSystem.sound().close();
   save(s);
 
-  autodetectYStart();
+  autodetectYStart(false);
 
   load(s);
   initializeAudio();
@@ -718,6 +720,20 @@ void Console::changeYStart(int direction)
   myTIA->frameReset();
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void Console::updateYStart(uInt32 ystart)
+{
+  if (ystart == TIAConstants::minYStart-1 && !myYStartAutodetected) {
+    redetectYStart();
+    ystart = myAutodetectedYstart;
+  } else if (ystart <= TIAConstants::maxYStart) myYStartAutodetected = false;
+
+  if (ystart <= TIAConstants::maxYStart) {
+    myTIA->setYStart(ystart);
+    myTIA->frameReset();
+  }
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void Console::changeHeight(int direction)
 {

src/emucore/Console.hxx

@@ -304,16 +304,21 @@ class Console : public Serializable
     */
     void toggleJitter() const;
 
+    /**
+     * Update yatart and run autodetection if necessary.
+     */
+    void updateYStart(uInt32 ystart);
+
   private:
     /**
      * Dry-run the emulation and detect the frame layout (PAL / NTSC).
      */
-    void autodetectFrameLayout();
+    void autodetectFrameLayout(bool reset = true);
 
     /**
      * Dryrun the emulation and detect ystart (the first visible scanline).
      */
-    void autodetectYStart();
+    void autodetectYStart(bool reset = true);
 
     /**
      * Rerun frame layout autodetection

src/emucore/tia/frame-manager/AbstractFrameManager.cxx

@@ -24,7 +24,6 @@ AbstractFrameManager::AbstractFrameManager() :
   myOnFrameComplete(nullptr)
 {
   layout(FrameLayout::ntsc);
-  reset();
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/tia/frame-manager/FrameLayoutDetector.cxx

@@ -42,6 +42,12 @@ FrameLayout FrameLayoutDetector::detectedLayout() const{
   return myPalFrames > myNtscFrames ? FrameLayout::pal : FrameLayout::ntsc;
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+FrameLayoutDetector::FrameLayoutDetector()
+{
+  reset();
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void FrameLayoutDetector::onReset()
 {

src/emucore/tia/frame-manager/FrameLayoutDetector.hxx

@@ -28,7 +28,7 @@
 class FrameLayoutDetector: public AbstractFrameManager {
   public:
 
-    FrameLayoutDetector() = default;
+    FrameLayoutDetector();
 
   public:
 

src/emucore/tia/frame-manager/FrameManager.cxx

@@ -49,6 +49,7 @@ FrameManager::FrameManager()
     myYStart(0),
     myJitterEnabled(false)
 {
+  reset();
   onLayoutChange();
 }
 

src/emucore/tia/frame-manager/YStartDetector.cxx

@@ -46,6 +46,12 @@ enum Metrics: uInt32 {
   initialGarbageFrames      = TIAConstants::initialGarbageFrames
 };
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+YStartDetector::YStartDetector()
+{
+  reset();
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 uInt32 YStartDetector::detectedYStart() const
 {

src/emucore/tia/frame-manager/YStartDetector.hxx

@@ -28,7 +28,7 @@ class YStartDetector: public AbstractFrameManager {
 
   public:
 
-    YStartDetector() = default;
+    YStartDetector();
 
   public:
 

src/gui/GameInfoDialog.cxx

@@ -560,12 +560,8 @@ void GameInfoDialog::saveConfig()
     // update 'Display' tab settings immediately
     bool reset = false;
     instance().console().setFormat(myFormat->getSelected());
-    if(uInt32(myYStart->getValue()) != TIAConstants::minYStart - 1 &&
-       uInt32(myYStart->getValue()) != instance().console().tia().ystart())
-    {
-      instance().console().tia().setYStart(myYStart->getValue());
-      reset = true;
-    }
+    instance().console().updateYStart(myYStart->getValue());
+
     if(uInt32(myHeight->getValue()) != TIAConstants::minViewableHeight - 1 &&
        uInt32(myHeight->getValue()) != instance().console().tia().height())
     {