Scale lines according to screen font size

src/core/StelProjector.cpp

@@ -21,6 +21,7 @@
 #include "StelTranslator.hpp"
 
 #include "StelProjector.hpp"
+#include "StelApp.hpp"
 
 #include <QDebug>
 #include <QString>
@@ -309,6 +310,13 @@ float StelProjector::getPixelPerRadAtCenter() const
 	return pixelPerRad;
 }
 
+float StelProjector::getScreenScale() const
+{
+	const float dppRatio = getDevicePixelsPerPixel();
+	const float fontRatio = StelApp::getInstance().screenFontSizeRatio();
+	return dppRatio * fontRatio;
+}
+
 //! Get the current FOV diameter in degrees
 float StelProjector::getFov() const {
 	return 360.f/static_cast<float>(M_PI)*viewScalingFactorToFov(0.5f*static_cast<float>(viewportFovDiameter)/pixelPerRad);

src/core/StelProjector.hpp

@@ -222,6 +222,10 @@ class StelProjector
 	//! Get size of a radian in pixels at the center of the viewport disk
 	float getPixelPerRadAtCenter() const;
 
+	//! Get the scale factor for objects drawn on screen. This takes into account
+	//! font size and the OS-given high-DPI scaling setting (see #getDevicePixelsPerPixel).
+	float getScreenScale() const;
+
 	//! Get the current FOV diameter in degrees
 	float getFov() const;
 

src/core/modules/ConstellationMgr.cpp

@@ -711,18 +711,19 @@ void ConstellationMgr::drawArt(StelPainter& sPainter, const Vec3d &obsVelocity)
 // Draw constellations lines
 void ConstellationMgr::drawLines(StelPainter& sPainter, const StelCore* core) const
 {
-	const float ppx = static_cast<float>(sPainter.getProjector()->getDevicePixelsPerPixel());
+	const float scale = sPainter.getProjector()->getScreenScale();
+
 	sPainter.setBlending(true);
-	if (constellationLineThickness>1 || ppx>1.f)
-		sPainter.setLineWidth(constellationLineThickness*ppx); // set line thickness
+	if (constellationLineThickness>1 || scale>1.f)
+		sPainter.setLineWidth(constellationLineThickness*scale); // set line thickness
 	sPainter.setLineSmooth(true);
 
 	const SphericalCap& viewportHalfspace = sPainter.getProjector()->getBoundingCap();
 	for (auto* constellation : constellations)
 	{
 		constellation->drawOptim(sPainter, core, viewportHalfspace);
 	}
-	if (constellationLineThickness>1 || ppx>1.f)
+	if (constellationLineThickness>1 || scale>1.f)
 		sPainter.setLineWidth(1); // restore line thickness
 	sPainter.setLineSmooth(false);
 }
@@ -1442,16 +1443,17 @@ bool ConstellationMgr::loadBoundaries(const QString& boundaryFile)
 
 void ConstellationMgr::drawBoundaries(StelPainter& sPainter, const Vec3d &obsVelocity) const
 {
-	const float ppx = static_cast<float>(sPainter.getProjector()->getDevicePixelsPerPixel());
+	const float scale = sPainter.getProjector()->getScreenScale();
+
 	sPainter.setBlending(false);
-	if (constellationBoundariesThickness>1 || ppx>1.f)
-		sPainter.setLineWidth(constellationBoundariesThickness*ppx); // set line thickness
+	if (constellationBoundariesThickness>1 || scale>1.f)
+		sPainter.setLineWidth(constellationBoundariesThickness*scale); // set line thickness
 	sPainter.setLineSmooth(true);
 	for (auto* constellation : constellations)
 	{
 		constellation->drawBoundaryOptim(sPainter, obsVelocity);
 	}
-	if (constellationBoundariesThickness>1 || ppx>1.f)
+	if (constellationBoundariesThickness>1 || scale>1.f)
 		sPainter.setLineWidth(1); // restore line thickness
 	sPainter.setLineSmooth(false);
 }

src/core/modules/Nebula.cpp

@@ -754,7 +754,7 @@ void Nebula::renderDarkNebulaMarker(StelPainter& sPainter, const float x, const
                                     float size, const Vec3f color) const
 {
 	// Take into account device pixel density and global scale ratio, as we are drawing 2D stuff.
-	const auto scale = sPainter.getProjector()->getDevicePixelsPerPixel();
+	const float scale = sPainter.getProjector()->getScreenScale();
 	size *= scale;
 
 	const float roundRadius = 0.35 * size;
@@ -841,7 +841,7 @@ void Nebula::renderMarkerRoundedRect(StelPainter& sPainter, const float x, const
                                      float size, const Vec3f color) const
 {
 	// Take into account device pixel density and global scale ratio, as we are drawing 2D stuff.
-	const auto scale = sPainter.getProjector()->getDevicePixelsPerPixel();
+	const float scale = sPainter.getProjector()->getScreenScale();
 	size *= scale;
 
 	const float roundRadius = 0.35 * size;
@@ -897,7 +897,7 @@ void Nebula::renderRoundMarker(StelPainter& sPainter, const float x, const float
                                float size, const Vec3f color, const bool crossed) const
 {
 	// Take into account device pixel density and global scale ratio, as we are drawing 2D stuff.
-	const auto scale = sPainter.getProjector()->getDevicePixelsPerPixel();
+	const float scale = sPainter.getProjector()->getScreenScale();
 	size *= scale;
 
 	sPainter.setBlending(true);
@@ -923,7 +923,7 @@ void Nebula::renderEllipticMarker(StelPainter& sPainter, const float x, const fl
                                   const float aspectRatio, const float angle, const Vec3f color) const
 {
 	// Take into account device pixel density and global scale ratio, as we are drawing 2D stuff.
-	const auto scale = sPainter.getProjector()->getDevicePixelsPerPixel();
+	const float scale = sPainter.getProjector()->getScreenScale();
 	size *= scale;
 
 	const float radiusY = 0.35 * size;
@@ -957,21 +957,21 @@ void Nebula::renderMarkerPointedCircle(StelPainter& sPainter, const float x, con
                                        float size, const Vec3f color, const bool insideRect) const
 {
 	// Take into account device pixel density and global scale ratio, as we are drawing 2D stuff.
-	const auto scale = sPainter.getProjector()->getDevicePixelsPerPixel();
+	const float scale = sPainter.getProjector()->getScreenScale();
 	size *= scale;
 
 	texPointElement->bind();
 	sPainter.setColor(color, hintsBrightness);
 	sPainter.setBlending(true, GL_SRC_ALPHA, GL_ONE);
-	const auto numPoints = StelUtils::getSmallerPowerOfTwo(std::clamp(int(0.4f*size), 8, 4096));
-	const auto spriteSize = std::min(0.25f * 2*M_PIf*size / numPoints, 5.f);
+	const auto numPoints = StelUtils::getSmallerPowerOfTwo(std::clamp(int(0.4f*size/scale), 8, 4096));
+	const auto spriteSize = std::min(0.25f * 2*M_PIf*size / numPoints, 5.f * scale);
 	if(insideRect)
 		size -= spriteSize*2;
 	const float*const cossin = StelUtils::ComputeCosSinRhoZone((2*M_PIf)/numPoints, numPoints, 0);
 	for(int n = 0; n < numPoints; ++n)
 	{
 		const auto cosa = cossin[2*n], sina = cossin[2*n+1];
-		sPainter.drawSprite2dMode(x - size*sina, y - size*cosa, spriteSize);
+		sPainter.drawSprite2dModeNoDeviceScale(x - size*sina, y - size*cosa, spriteSize);
 	}
 }
 
@@ -981,7 +981,12 @@ float Nebula::getHintSize(StelPainter& sPainter) const
 	float scaledSize = 0.0f;
 	// Should getPixelPerRadAtCenter() not adjust for HiDPI? Apparently it does not!
 	if (drawHintProportional)
-		scaledSize = static_cast<float>(getAngularRadius(Q_NULLPTR)) *(M_PI_180f)*static_cast<float>(sPainter.getProjector()->getPixelPerRadAtCenter()) / static_cast<float>(sPainter.getProjector()->getDevicePixelsPerPixel());
+	{
+		const float scale = sPainter.getProjector()->getScreenScale();
+		const float angularRadiusAtCenter = static_cast<float>(getAngularRadius(nullptr)) * M_PI_180f;
+		const float pixPerRadAtCenter = static_cast<float>(sPainter.getProjector()->getPixelPerRadAtCenter());
+		scaledSize = angularRadiusAtCenter * pixPerRadAtCenter / scale;
+	}
 	// TODO: Is it correct that for NebRegions any catalog data for getAngularRadius() is ignored? And that NebRegions are ALWAYS drawn with larger symbol?
 	if (nType==NebRegion)
 		scaledSize = 12.f;