Attempt at fixing spheric mirror effect on retina

This commit will at least make the rendering work, as long
as we don't resize the window!  It mostly makes sure that
the effect buffer size is using the actual screen pixel size
and not the logical size.

It's not good.  The code it quite complex and we have to jungle
with the screen scale (pixelsPerPixel) in a few places where it
shouldn't matter.

The input handling is also broken.

Need to keep working on that.

src/core/StelApp.cpp

@@ -956,7 +956,7 @@ void StelApp::quit()
 void StelApp::setDevicePixelsPerPixel(float dppp)
 {
 	// Check that the device-independent pixel size didn't change
-	if (devicePixelsPerPixel!=dppp)
+	if (!viewportEffect && devicePixelsPerPixel!=dppp)
 	{
 		devicePixelsPerPixel = dppp;
 		StelProjector::StelProjectorParams params = core->getCurrentStelProjectorParams();

src/core/StelViewportEffect.cpp

@@ -72,21 +72,22 @@ StelViewportDistorterFisheyeToSphericMirror::StelViewportDistorterFisheyeToSpher
 	core->getMovementMgr()->setMaxFov(distorter_max_fov);
 
 	// width of the not yet distorted image
-	newProjectorParams.viewportXywh[2] = conf.value("spheric_mirror/newProjectorParams.viewportXywh[2]idth", originalProjectorParams.viewportXywh[2]).toInt();
+	newProjectorParams.devicePixelsPerPixel = 1;
+	newProjectorParams.viewportXywh[2] = conf.value("spheric_mirror/newProjectorParams.viewportXywh[2]idth", originalProjectorParams.viewportXywh[2] * params.devicePixelsPerPixel).toInt();
 	if (newProjectorParams.viewportXywh[2] <= 0)
 	{
-		newProjectorParams.viewportXywh[2] = originalProjectorParams.viewportXywh[2];
+		newProjectorParams.viewportXywh[2] = originalProjectorParams.viewportXywh[2] * params.devicePixelsPerPixel;
 	}
 	else if (newProjectorParams.viewportXywh[2] > screen_w)
 	{
 		newProjectorParams.viewportXywh[2] = screen_w;
 	}
 
 	// height of the not yet distorted image
-	newProjectorParams.viewportXywh[3] = conf.value("spheric_mirror/newProjectorParams.viewportXywh[3]eight", originalProjectorParams.viewportXywh[3]).toInt();
+	newProjectorParams.viewportXywh[3] = conf.value("spheric_mirror/newProjectorParams.viewportXywh[3]eight", originalProjectorParams.viewportXywh[3] * params.devicePixelsPerPixel).toInt();
 	if (newProjectorParams.viewportXywh[3] <= 0)
 	{
-		newProjectorParams.viewportXywh[3] = originalProjectorParams.viewportXywh[3];
+		newProjectorParams.viewportXywh[3] = originalProjectorParams.viewportXywh[3] * params.devicePixelsPerPixel;
 	}
 	else if (newProjectorParams.viewportXywh[3] > screen_h)
 	{
@@ -106,8 +107,6 @@ StelViewportDistorterFisheyeToSphericMirror::StelViewportDistorterFisheyeToSpher
 	newProjectorParams.viewportXywh[0] = (screen_w-newProjectorParams.viewportXywh[2]) >> 1;
 	newProjectorParams.viewportXywh[1] = (screen_h-newProjectorParams.viewportXywh[3]) >> 1;
 
-	newProjectorParams.viewportXywh[2] *= originalProjectorParams.devicePixelsPerPixel;
-	newProjectorParams.viewportXywh[3] *= originalProjectorParams.devicePixelsPerPixel;
 	StelApp::getInstance().getCore()->setCurrentStelProjectorParams(newProjectorParams);
 
 	// init transformation
@@ -248,13 +247,7 @@ StelViewportDistorterFisheyeToSphericMirror::~StelViewportDistorterFisheyeToSphe
 {
 	if (texture_point_array)
 		delete[] texture_point_array;
-
-	// TODO repair
-	// prj->setMaxFov(original_max_fov);
-	//	prj->setViewport(original_viewport[0],original_viewport[1],
-	// 	                 original_viewport[2],original_viewport[3],
-	// 	                 original_viewportCenter[0],original_viewportCenter[1],
-	// 	                 original_viewportFovDiameter);
+	StelApp::getInstance().getCore()->setCurrentStelProjectorParams(originalProjectorParams);
 }