Added boolean parameter to make knobs snap, made them visually snap as

well

README.md

@@ -20,7 +20,7 @@ Rack's dependencies (GLEW, glfw, etc) do not need to be installed on your system
 ### Mac
 
 Install [Xcode](https://developer.apple.com/xcode/).
-Install [CMake](https://cmake.org/) and wget, preferably from [Homebrew](https://brew.sh/).
+Install [CMake](https://cmake.org/) (for some of Rack's dependencies) and wget, preferably from [Homebrew](https://brew.sh/).
 
 ### Windows
 

include/app.hpp

@@ -183,6 +183,9 @@ struct ParamWidget : OpaqueWidget, QuantityWidget {
 
 /** Implements vertical dragging behavior for ParamWidgets */
 struct Knob : ParamWidget {
+	/** Snap to nearest integer while dragging */
+	bool snap = false;
+	float snapValue;
 	void onDragStart();
 	void onDragMove(Vec mouseRel);
 	void onDragEnd();
@@ -209,14 +212,6 @@ struct SVGKnob : virtual Knob, FramebufferWidget {
 	void onChange();
 };
 
-/** Snaps to the nearest integer value on mouse release */
-struct SnapKnob : virtual Knob {
-	void onDragEnd() {
-		setValue(roundf(value));
-		Knob::onDragEnd();
-	}
-};
-
 struct SVGSlider : Knob, FramebufferWidget {
 	/** Intermediate positions will be interpolated between these positions */
 	Vec minHandlePos, maxHandlePos;

include/components.hpp

@@ -57,7 +57,11 @@ struct RoundHugeBlackKnob : RoundBlackKnob {
 	}
 };
 
-struct RoundSmallBlackSnapKnob : RoundSmallBlackKnob, SnapKnob {};
+struct RoundSmallBlackSnapKnob : RoundSmallBlackKnob {
+	RoundSmallBlackSnapKnob() {
+		snap = true;
+	}
+};
 
 
 struct Davies1900hKnob : SVGKnob {
@@ -109,7 +113,11 @@ struct Davies1900hSmallBlackKnob : Davies1900hKnob {
 	}
 };
 
-struct Davies1900hSmallBlackSnapKnob : Davies1900hSmallBlackKnob, SnapKnob {};
+struct Davies1900hSmallBlackSnapKnob : Davies1900hSmallBlackKnob {
+	Davies1900hSmallBlackSnapKnob() {
+		snap = true;
+	}
+};
 
 
 struct Rogan : SVGKnob {
@@ -366,7 +374,11 @@ struct BefacoBigKnob : SVGKnob {
 	}
 };
 
-struct BefacoBigSnapKnob : BefacoBigKnob, SnapKnob {};
+struct BefacoBigSnapKnob : BefacoBigKnob {
+	BefacoBigSnapKnob() {
+		snap = true;
+	}
+};
 
 struct BefacoTinyKnob : SVGKnob {
 	BefacoTinyKnob() {

src/app/Knob.cpp

@@ -12,6 +12,7 @@ namespace rack {
 
 void Knob::onDragStart() {
 	guiCursorLock();
+	snapValue = value;
 	randomizable = false;
 }
 
@@ -19,7 +20,11 @@ void Knob::onDragMove(Vec mouseRel) {
 	// Drag slower if Mod
 	if (guiIsModPressed())
 		mouseRel = mouseRel.mult(1/16.0);
-	setValue(value - KNOB_SENSITIVITY * (maxValue - minValue) * mouseRel.y);
+	snapValue += KNOB_SENSITIVITY * (maxValue - minValue) * -mouseRel.y;
+	if (snap)
+		setValue(roundf(snapValue));
+	else
+		setValue(snapValue);
 }
 
 void Knob::onDragEnd() {