Add pixelRatio to settings.

include/settings.hpp

@@ -43,6 +43,10 @@ static const float zoomMax = 2.f;
 static const float zoomMin = -2.f;
 /** Reverse the zoom scroll direction */
 extern bool invertZoom;
+/** Ratio between UI pixel and physical screen pixel.
+0 for auto.
+*/
+extern float pixelRatio;
 /** Opacity of cables in the range [0, 1] */
 extern float cableOpacity;
 /** Straightness of cables in the range [0, 1]. Unitless and arbitrary. */

src/Window.cpp

@@ -435,13 +435,18 @@ void Window::step() {
 		internal->lastWindowTitle = windowTitle;
 	}
 
-	// Get desired scaling
+	// Get desired pixel ratio
 	float newPixelRatio;
-	glfwGetWindowContentScale(win, &newPixelRatio, NULL);
-	newPixelRatio = std::floor(newPixelRatio + 0.5);
+	if (settings::pixelRatio > 0.0) {
+		newPixelRatio = settings::pixelRatio;
+	}
+	else {
+		glfwGetWindowContentScale(win, &newPixelRatio, NULL);
+		newPixelRatio = std::floor(newPixelRatio + 0.5);
+	}
 	if (newPixelRatio != pixelRatio) {
-		APP->event->handleDirty();
 		pixelRatio = newPixelRatio;
+		APP->event->handleDirty();
 	}
 
 	// Get framebuffer/window ratio

src/settings.cpp

@@ -26,6 +26,7 @@ math::Vec windowSize = math::Vec(1024, 768);
 math::Vec windowPos = math::Vec(NAN, NAN);
 float zoom = 0.0;
 bool invertZoom = false;
+float pixelRatio = 0.0;
 float cableOpacity = 0.5;
 float cableTension = 0.5;
 float rackBrightness = 1.0;
@@ -104,6 +105,8 @@ json_t* toJson() {
 
 	json_object_set_new(rootJ, "invertZoom", json_boolean(invertZoom));
 
+	json_object_set_new(rootJ, "pixelRatio", json_real(pixelRatio));
+
 	json_object_set_new(rootJ, "cableOpacity", json_real(cableOpacity));
 
 	json_object_set_new(rootJ, "cableTension", json_real(cableTension));
@@ -224,6 +227,10 @@ void fromJson(json_t* rootJ) {
 	if (invertZoomJ)
 		invertZoom = json_boolean_value(invertZoomJ);
 
+	json_t* pixelRatioJ = json_object_get(rootJ, "pixelRatio");
+	if (pixelRatioJ)
+		pixelRatio = json_number_value(pixelRatioJ);
+
 	json_t* cableOpacityJ = json_object_get(rootJ, "cableOpacity");
 	if (cableOpacityJ)
 		cableOpacity = json_number_value(cableOpacityJ);

src/widget/FramebufferWidget.cpp

@@ -191,7 +191,8 @@ void FramebufferWidget::render(math::Vec scale, math::Vec offsetF, math::Rect cl
 	internal->fbBox = math::Rect::fromMinMax(min, max);
 	// DEBUG("%g %g %g %g", RECT_ARGS(internal->fbBox));
 
-	math::Vec newFbSize = internal->fbBox.size.mult(APP->window->pixelRatio).ceil();
+	float pixelRatio = std::fmax(1.f, std::floor(APP->window->pixelRatio));
+	math::Vec newFbSize = internal->fbBox.size.mult(pixelRatio).ceil();
 
 	// Create framebuffer if a new size is needed
 	if (!internal->fb || !newFbSize.equals(internal->fbSize)) {