Hires screenshot (Stellarium#141)

* Docfix and use canonical Q_NULLPTR.

* Towards custom-sized screenshots!

Unfinished. Basic operation and GUI editing OK.
Button bars are currently not yet visible. For large sizes,
font and dialogs become smallish as expected (like on 4k devices).
Maybe this requires an artificial pixel aspect ratio?

* Replace inputMask by QIntValidator, fixes GUI problems.

* Forgot remembering a button, docfixes.

* Proper relocation of button bars for screenshot.

Need another scale factor that can be used by
other components like StarMgr to adjust some settings.
Also enable compiling with old widgets (deactivates hi-res screenshot)
A bit of cleanup

* Solve screenshot image format issues when running OpenGL ES

* Guide note on screenshots

* GUI improvement for screenshot sizes

* Exclude diagnostic test on OSX

Still unclear under which circumstances we
can trigger a fatal memory error.

guide/app_config_ini.tex

@@ -502,11 +502,14 @@ \subsection{\big[main\big]}
 \begin{tabularx}{\textwidth}{l|l|X}\toprule
 \emph{ID}                 & \emph{Type} & \emph{Description}\\\midrule
 invert\_screenshots\_colors & bool   & If \emph{true}, Stellarium will saving the screenshorts with inverted colors.\\%\midrule
-restore\_defaults           & bool   & If \emph{true}, Stellarium will restore default settings at startup. 
-                                       This is equivalent to calling Stellarium with the \command{--restore-defaults} option.\\%\midrule
 screenshot\_dir             & string & Path for saving screenshots\\%\midrule
+screenshot\_custom\_size    & bool   & \emph{true} if you want to specify particular dimensions next:\\
+screenshot\_custom\_width   & int    & custom width of screenshots. Max.\ available size is hardware dependent!\\
+screenshot\_custom\_height  & int    & custom height of screenshots. Max.\ available size is hardware dependent!\\\midrule
 version                     & string & Version of Stellarium. This parameter may be used to detect necessary changes in config.ini file, do not edit.\\%\midrule
 use\_separate\_output\_file & bool   & Set to \emph{true} if you want to create a new file for script output for each start of Stellarium\\%\midrule
+restore\_defaults           & bool   & If \emph{true}, Stellarium will restore default settings at startup. 
+                                       This is equivalent to calling Stellarium with the \command{--restore-defaults} option.\\%\midrule
 ignore\_opengl\_warning     & bool   & Set to \emph{true} if you don't want to see OpenGL warnings for each start of Stellarium.\\%\midrule
 check\_requirements         & bool   & Set to \emph{false} if you want to disable and permanently ignore checking hardware requirements at startup. 
                                        Expect problems if hardware is below requirements!\\

guide/ch_interface.tex

@@ -272,8 +272,14 @@ \subsection{The Tools Tab}
 \item[Indication for mount mode] You can activate the short display of a message when switching type of used mount.
 \end{description}
 
-\noindent In addition, you can set the directory where screenshots will be stored, 
-and you can download more star catalogs on this tab.
+\noindent In addition, you can set the directory where screenshots
+will be stored, and \newFeature{0.18.1} also whether you want
+screenshots sized like Stellarium's window or some other, likely
+larger size. The maximum possible size depends on your
+hardware. $4096\times4096$ should be possible on most PCs, others may
+even create $16384\times16384$ images.
+
+Another button allows you to download more star catalogs on this tab.
 
 \subsection{The Scripts Tab}
 \label{sec:gui:scripts}

src/StelMainView.cpp

@@ -25,11 +25,14 @@
 #include "StelModuleMgr.hpp"
 #include "StelPainter.hpp"
 #include "StelGui.hpp"
+#include "SkyGui.hpp"
 #include "StelTranslator.hpp"
 #include "StelUtils.hpp"
 #include "StelActionMgr.hpp"
 #include "StelOpenGL.hpp"
 #include "StelOpenGLArray.hpp"
+#include "StelProjector.hpp"
+#include "StelMovementMgr.hpp"
 
 #include <QDebug>
 #include <QDir>
@@ -68,6 +71,9 @@
 #ifdef OPENGL_DEBUG_LOGGING
 #include <QOpenGLDebugLogger>
 #endif
+#include <QLoggingCategory>
+
+Q_LOGGING_CATEGORY(mainview, "stel.MainView")
 
 #include <clocale>
 
@@ -561,6 +567,12 @@ StelMainView::StelMainView(QSettings* settings)
 	  updateQueued(false),
 	  flagInvertScreenShotColors(false),
 	  flagOverwriteScreenshots(false),
+#ifndef USE_OLD_QGLWIDGET
+	  flagUseCustomScreenshotSize(false),
+	  customScreenshotWidth(1024),
+	  customScreenshotHeight(768),
+	  customScreenshotMagnification(1.0f),
+#endif
 	  screenShotPrefix("stellarium-"),
 	  screenShotDir(""),
 	  flagCursorTimeout(false),
@@ -720,8 +732,7 @@ QSurfaceFormat StelMainView::getDesiredGLFormat() const
 	fmt.setBlueBufferSize(8);
 	fmt.setAlphaBufferSize(8);
 	fmt.setDepthBufferSize(24);
-	//I dont think we use the stencil buffer for anything
-	//but maybe Qt needs it
+	//Stencil buffer seems necessary for GUI boxes
 	fmt.setStencilBufferSize(8);
 
 #ifdef OPENGL_DEBUG_LOGGING
@@ -773,7 +784,7 @@ void StelMainView::init()
 
 	QSettings* conf = configuration;
 
-	// Should be check of requirements disabled?
+	// Should be check of requirements disabled? -- NO! This is intentional here, and does no harm.
 	if (conf->value("main/check_requirements", true).toBool())
 	{
 		// Find out lots of debug info about supported version of OpenGL and vendor/renderer.
@@ -843,6 +854,11 @@ void StelMainView::init()
 	}
 
 	flagInvertScreenShotColors = conf->value("main/invert_screenshots_colors", false).toBool();
+#ifndef USE_OLD_QGLWIDGET
+	flagUseCustomScreenshotSize=conf->value("main/screenshot_custom_size", false).toBool();
+	customScreenshotWidth=conf->value("main/screenshot_custom_width", 1024).toUInt();
+	customScreenshotHeight=conf->value("main/screenshot_custom_height", 768).toUInt();
+#endif
 	setFlagCursorTimeout(conf->value("gui/flag_mouse_cursor_timeout", false).toBool());
 	setCursorTimeout(conf->value("gui/mouse_cursor_timeout", 10.f).toFloat());
 	setMaxFps(conf->value("video/maximum_fps",10000.f).toFloat());
@@ -1398,23 +1414,113 @@ void StelMainView::doScreenshot(void)
 #ifdef USE_OLD_QGLWIDGET
 	QImage im = glWidget->grabFrameBuffer();
 #else
+	// Make a screenshot which may be larger than the current window. This is harder than you would think:
+	// fbObj the framebuffer governs size of the target image, that's the easy part, but it also has its limits.
+	// However, the GUI parts need to be placed properly,
+	// HiDPI screens interfere, and the viewing angle has to be maintained.
+	// First, image size:
 	glWidget->makeCurrent();
 	float pixelRatio = QOpenGLContext::currentContext()->screen()->devicePixelRatio();
+	int imgWidth =stelScene->width()  * pixelRatio;
+	int imgHeight=stelScene->height() * pixelRatio;
+	if (flagUseCustomScreenshotSize)
+	{
+		// Borrowed from Scenery3d renderer: determine maximum framebuffer size as minimum of texture, viewport and renderbuffer size
+		QOpenGLContext *context = QOpenGLContext::currentContext();
+		if (context)
+		{
+			context->functions()->initializeOpenGLFunctions();
+			//qDebug() << "initializeOpenGLFunctions()...";
+#ifndef Q_OS_MAC
+			// Make sure we have enough free GPU memory!
+			GLint freeGLmemory;
+			context->functions()->glGetIntegerv(GL_GPU_MEMORY_INFO_CURRENT_AVAILABLE_VIDMEM_NVX, &freeGLmemory);
+			qCDebug(mainview)<<"Free GPU memory:" << freeGLmemory << "kB -- we ask for " << customScreenshotWidth*customScreenshotHeight*8 / 1024 <<"kB";
+			GLint freeGLmemoryAMD[4];
+			context->functions()->glGetIntegerv(GL_RENDERBUFFER_FREE_MEMORY_ATI, freeGLmemoryAMD);
+			qCDebug(mainview)<<"Free GPU memory (AMD version):" << (uint)freeGLmemoryAMD[1]/1024 << "+" << (uint)freeGLmemoryAMD[3]/1024 << " of " << (uint)freeGLmemoryAMD[0]/1024 << "+" << (uint)freeGLmemoryAMD[2]/1024 << "kB -- we ask for " << customScreenshotWidth*customScreenshotHeight*8 / 1024 <<"kB";
+#endif
+
+			GLint texSize,viewportSize[2],rbSize;
+			context->functions()->glGetIntegerv(GL_MAX_TEXTURE_SIZE, &texSize);
+			context->functions()->glGetIntegerv(GL_MAX_VIEWPORT_DIMS, viewportSize);
+			context->functions()->glGetIntegerv(GL_MAX_RENDERBUFFER_SIZE, &rbSize);
+			qCDebug(mainview)<<"Maximum texture size:"<<texSize;
+			qCDebug(mainview)<<"Maximum viewport dims:"<<viewportSize[0]<<viewportSize[1];
+			qCDebug(mainview)<<"Maximum renderbuffer size:"<<rbSize;
+			int maximumFramebufferSize = qMin(texSize,qMin(rbSize,qMin(viewportSize[0],viewportSize[1])));
+			qCDebug(mainview)<<"Maximum framebuffer size:"<<maximumFramebufferSize;
+
+			imgWidth =qMin(maximumFramebufferSize, customScreenshotWidth);
+			imgHeight=qMin(maximumFramebufferSize, customScreenshotHeight);
+		}
+		else
+		{
+			qCWarning(mainview) << "No GL context for screenshot! Aborting.";
+			return;
+		}
+	}
+	// The texture format depends on used GL version. RGB is fine on OpenGL. on GLES, we must use RGBA and circumvent problems with a few more steps.
+	bool isGLES=(QOpenGLContext::currentContext()->format().renderableType() == QSurfaceFormat::OpenGLES);
+
 	QOpenGLFramebufferObjectFormat fbFormat;
 	fbFormat.setAttachment(QOpenGLFramebufferObject::CombinedDepthStencil);
-	fbFormat.setInternalTextureFormat(GL_RGB); // avoid transparent background!
-	QOpenGLFramebufferObject * fbObj = new QOpenGLFramebufferObject(stelScene->width() * pixelRatio, stelScene->height() * pixelRatio, fbFormat);
+	fbFormat.setInternalTextureFormat(isGLES ? GL_RGBA : GL_RGB); // try to avoid transparent background!
+	QOpenGLFramebufferObject * fbObj = new QOpenGLFramebufferObject(imgWidth, imgHeight, fbFormat);
 	fbObj->bind();
-	QOpenGLPaintDevice fbObjPaintDev(stelScene->width(), stelScene->height());
+	// Now the painter has to be convinced to paint to the potentially larger image frame.
+	QOpenGLPaintDevice fbObjPaintDev(imgWidth, imgHeight);
 	fbObjPaintDev.setDevicePixelRatio(pixelRatio);
+
+	// It seems the projector has its own knowledge about image size. We must adjust fov and image size, but reset afterwards.
+	StelProjector::StelProjectorParams pParams=StelApp::getInstance().getCore()->getCurrentStelProjectorParams();
+	StelProjector::StelProjectorParams sParams=pParams;
+	//qCDebug(mainview) << "Screenshot Viewport: x" << pParams.viewportXywh[0] << "/y" << pParams.viewportXywh[1] << "/w" << pParams.viewportXywh[2] << "/h" << pParams.viewportXywh[3];
+	sParams.viewportXywh[2]=imgWidth;
+	sParams.viewportXywh[3]=imgHeight;
+
+	// Configure a helper value to allow some modules to tweak their output sizes. Currently used by StarMgr, maybe solve font issues?
+	customScreenshotMagnification=imgHeight/QApplication::desktop()->screenGeometry().height();
+
+	sParams.viewportCenter.set(0.0+(0.5+pParams.viewportCenterOffset.v[0])*imgWidth, 0.0+(0.5+pParams.viewportCenterOffset.v[1])*imgHeight);
+	sParams.viewportFovDiameter = qMin(imgWidth,imgHeight);
+	StelApp::getInstance().getCore()->setCurrentStelProjectorParams(sParams);
+
 	QPainter painter;
-	painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing);
 	painter.begin(&fbObjPaintDev);
-	stelScene->render(&painter);
+	// next line was above begin(), but caused a complaint. Maybe use after begin()?
+	painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing);
+	stelScene->setSceneRect(0, 0, imgWidth, imgHeight);
+
+	// push the button bars back to the sides where they belong, and fix root item clipping its children.
+	dynamic_cast<StelGui*>(gui)->getSkyGui()->setGeometry(0, 0, imgWidth, imgHeight);
+	rootItem->setSize(QSize(imgWidth, imgHeight));
+	dynamic_cast<StelGui*>(gui)->forceRefreshGui(); // refresh bar position.
+
+	stelScene->render(&painter, QRectF(), QRectF(0,0,imgWidth,imgHeight) , Qt::KeepAspectRatio);
 	painter.end();
-	QImage im = fbObj->toImage();
+
+	QImage im;
+	if (isGLES)
+	{
+		// We have RGBA texture with possibly empty spots when atmosphere was off.
+		// See toImage() help entry why to create wrapper here.
+		QImage fboImage(fbObj->toImage());
+		//qDebug() << "FBOimage format:" << fboImage.format(); // returns Format_RGBA8888_Premultiplied
+		QImage im2(fboImage.constBits(), fboImage.width(), fboImage.height(), QImage::Format_RGBX8888);
+		im=im2.copy();
+	}
+	else
+		im=fbObj->toImage();
 	fbObj->release();
 	delete fbObj;
+	// reset viewport and GUI
+	StelApp::getInstance().getCore()->setCurrentStelProjectorParams(pParams);
+	customScreenshotMagnification=1.0f;
+	stelScene->setSceneRect(0, 0, pParams.viewportXywh[2], pParams.viewportXywh[3]);
+	rootItem->setSize(QSize(pParams.viewportXywh[2], pParams.viewportXywh[3]));
+	dynamic_cast<StelGui*>(gui)->getSkyGui()->setGeometry(0, 0, pParams.viewportXywh[2], pParams.viewportXywh[3]);
+	dynamic_cast<StelGui*>(gui)->forceRefreshGui();
 #endif
 
 	if (flagInvertScreenShotColors)
@@ -1502,15 +1608,15 @@ void StelMainView::glContextDoneCurrent()
 	glWidget->doneCurrent();
 }
 
-//! Set the sky background color. Everything else than black creates an work of art!
+// Set the sky background color. Everything else than black creates a work of art!
 void StelMainView::setSkyBackgroundColor(Vec3f color)
 {
 	rootItem->setSkyBackgroundColor(color);
 	StelApp::getInstance().getSettings()->setValue("color/sky_background_color", StelUtils::vec3fToStr(color));
 	emit skyBackgroundColorChanged(color);
 }
 
-//! Get the sky background color. Everything else than black creates an work of art!
+// Get the sky background color. Everything else than black creates a work of art!
 Vec3f StelMainView::getSkyBackgroundColor()
 {
 	return rootItem->getSkyBackgroundColor();

src/StelMainView.hpp

@@ -51,6 +51,11 @@ class StelMainView : public QGraphicsView
 	Q_PROPERTY(bool fullScreen                 READ isFullScreen                  WRITE setFullScreen                 NOTIFY fullScreenChanged)
 	Q_PROPERTY(bool flagInvertScreenShotColors READ getFlagInvertScreenShotColors WRITE setFlagInvertScreenShotColors NOTIFY flagInvertScreenShotColorsChanged)
 	Q_PROPERTY(bool flagOverwriteScreenshots   READ getFlagOverwriteScreenShots   WRITE setFlagOverwriteScreenShots   NOTIFY flagOverwriteScreenshotsChanged)
+#ifndef USE_OLD_QGLWIDGET
+	Q_PROPERTY(bool flagUseCustomScreenshotSize READ getFlagUseCustomScreenshotSize WRITE setFlagUseCustomScreenshotSize NOTIFY flagUseCustomScreenshotSizeChanged)
+	Q_PROPERTY(int  customScreenshotWidth      READ getCustomScreenshotWidth      WRITE setCustomScreenshotWidth      NOTIFY customScreenshotWidthChanged)
+	Q_PROPERTY(int  customScreenshotHeight     READ getCustomScreenshotHeight     WRITE setCustomScreenshotHeight     NOTIFY customScreenshotHeightChanged)
+#endif
 	Q_PROPERTY(bool flagUseButtonsBackground   READ getFlagUseButtonsBackground   WRITE setFlagUseButtonsBackground   NOTIFY flagUseButtonsBackgroundChanged)
 	Q_PROPERTY(bool flagCursorTimeout          READ getFlagCursorTimeout          WRITE setFlagCursorTimeout          NOTIFY flagCursorTimeoutChanged)
 	Q_PROPERTY(double cursorTimeout            READ getCursorTimeout              WRITE setCursorTimeout              NOTIFY cursorTimeoutChanged)
@@ -131,6 +136,23 @@ public slots:
 	//! Set whether existing files are overwritten when saving screenshot
 	void setFlagOverwriteScreenShots(bool b) {flagOverwriteScreenshots=b; emit flagOverwriteScreenshotsChanged(b);}
 
+#ifndef USE_OLD_QGLWIDGET
+	//! Get whether custom size should be used for screenshots
+	bool getFlagUseCustomScreenshotSize() const {return flagUseCustomScreenshotSize;}
+	//! Set whether custom size should be used for screenshots
+	void setFlagUseCustomScreenshotSize(bool b) {flagUseCustomScreenshotSize=b; emit flagUseCustomScreenshotSizeChanged(b);}
+	//! Get custom screenshot width
+	int getCustomScreenshotWidth() const {return customScreenshotWidth;}
+	//! Set whether custom size should be used for screenshots
+	void setCustomScreenshotWidth(int width) {customScreenshotWidth=width; emit customScreenshotWidthChanged(width);}
+	//! Get custom screenshot height
+	int getCustomScreenshotHeight() const {return customScreenshotHeight;}
+	//! Set whether custom size should be used for screenshots
+	void setCustomScreenshotHeight(int height) {customScreenshotHeight=height; emit customScreenshotHeightChanged(height);}
+	//! Get screenshot magnification. This should be used by StarMgr, text drawing and other elements which may
+	//! want to enlarge their output in screenshots to keep them visible.
+	float getCustomScreenshotMagnification() {return customScreenshotMagnification;}
+#endif
 	//! Get the state of the mouse cursor timeout flag
 	bool getFlagCursorTimeout() {return flagCursorTimeout;}
 	//! Get the state of the mouse cursor timeout flag
@@ -168,9 +190,9 @@ public slots:
 	//! Get the state of the flag of usage background for GUI buttons
 	bool getFlagUseButtonsBackground() { return flagUseButtonsBackground; }
 
-	//! Set the sky background color. (Actually forwards to the StelRootItem.)  Everything else than black creates an work of art!
+	//! Set the sky background color. (Actually forwards to the StelRootItem.)  Everything else than black creates a work of art!
 	void setSkyBackgroundColor(Vec3f color);
-	//! Get the sky background color. (Actually retrieves from the StelRootItem.)  Everything else than black creates an work of art!
+	//! Get the sky background color. (Actually retrieves from the StelRootItem.)  Everything else than black creates a work of art!
 	Vec3f getSkyBackgroundColor();
 
 protected:
@@ -200,6 +222,10 @@ public slots:
 	void updateIconsRequested();
 	void flagInvertScreenShotColorsChanged(bool b);
 	void flagOverwriteScreenshotsChanged(bool b);
+	void flagUseCustomScreenshotSizeChanged(bool use);
+	void customScreenshotWidthChanged(int width);
+	void customScreenshotHeightChanged(int height);
+
 	void flagUseButtonsBackgroundChanged(bool b);
 	void skyBackgroundColorChanged(Vec3f color);
 	void flagCursorTimeoutChanged(bool b);
@@ -255,7 +281,12 @@ private slots:
 	bool updateQueued;
 	bool flagInvertScreenShotColors;
 	bool flagOverwriteScreenshots; //! if set to true, screenshot is named exactly screenShotPrefix.png and overwrites existing file
-
+#ifndef USE_OLD_QGLWIDGET
+	bool flagUseCustomScreenshotSize; //! if true, the next 2 values are observed for screenshots.
+	int customScreenshotWidth;            //! used when flagCustomResolutionScreenshots==true
+	int customScreenshotHeight;           //! used when flagCustomResolutionScreenshots==true
+	float customScreenshotMagnification;  //! tracks the magnification factor customScreenshotHeight/NormalWindowHeight
+#endif
 	QString screenShotPrefix;
 	QString screenShotDir;
 

src/core/StelHips.hpp

@@ -74,10 +74,10 @@ class HipsSurvey : public QObject
 	//! Render the survey.
 	//! @param sPainter the painter to use.
 	//! @param angle total visible angle of the survey in radians. This is used to optimize the rendering of planet
-	//         surveys.  Should be set to 2 pi for sky surveys.
+	//!         surveys.  Should be set to 2 pi for sky surveys.
 	//! @param callback if set this will be called for each visible tile, and the callback should do it rendering
-	//         itself.  If set to NULL, the function will draw the tiles using the default shader.
-	void draw(StelPainter* sPainter, double angle = 2 * M_PI, DrawCallback callback = nullptr);
+	//!         itself.  If set to Q_NULLPTR, the function will draw the tiles using the default shader.
+	void draw(StelPainter* sPainter, double angle = 2.0 * M_PI, DrawCallback callback = Q_NULLPTR);
 
 	//! Return the source URL of the survey.
 	const QString& getUrl() const {return url;}

src/core/StelPainter.hpp

@@ -205,9 +205,9 @@ class StelPainter : protected QOpenGLFunctions
 	//! @param stacks: number of horizontal segments ("latitude zones")
 	//! @param orientInside: 1 to have normals point inside, e.g. for Milky Way, Zodiacal Light, etc.
 	//! @param flipTexture: if texture should be mapped to inside of sphere, e.g. Milky Way.
-	//! @param topAngle GZ: new parameter. An opening angle [radians] at top of the sphere. Useful if there is an empty
+	//! @param topAngle: An opening angle [radians] at top of the sphere. Useful if there is an empty
 	//!        region around the top pole, like North Galactic Pole.
-	//! @param bottomAngle GZ: new parameter. An opening angle [radians] at bottom of the sphere. Useful if there is an empty
+	//! @param bottomAngle: An opening angle [radians] at bottom of the sphere. Useful if there is an empty
 	//!        region around the bottom pole, like South Galactic Pole.
 	static StelVertexArray computeSphereNoLight(float radius, float oneMinusOblateness, int slices, int stacks,
                             int orientInside = 0, bool flipTexture = false,

src/core/StelSkyDrawer.cpp

@@ -29,6 +29,9 @@
 #include "StelUtils.hpp"
 #include "StelMovementMgr.hpp"
 #include "StelPainter.hpp"
+#ifndef USE_OLD_QGLWIDGET
+#include "StelMainView.hpp"
+#endif
 
 #include "StelModuleMgr.hpp"
 #include "LandscapeMgr.hpp"
@@ -344,7 +347,9 @@ bool StelSkyDrawer::computeRCMag(float mag, RCMag* rcMag) const
 {
 	rcMag->radius = eye->adaptLuminanceScaledLn(pointSourceMagToLnLuminance(mag), starRelativeScale*1.40f/2.f);
 	rcMag->radius *=starLinearScale;
-
+#ifndef USE_OLD_QGLWIDGET
+	rcMag->radius *=StelMainView::getInstance().getCustomScreenshotMagnification();
+#endif
 	// Use now statically min_rmag = 0.5, because higher and too small values look bad
 	if (rcMag->radius < 0.3f)
 	{