Fix dropdown menu offset when zooming

include/math.hpp

@@ -271,6 +271,21 @@ struct Rect {
 		r.pos.y = clampf(pos.y, bound.pos.y, bound.pos.y + bound.size.y - size.y);
 		return r;
 	}
+	/** Expands this Rect to contain `other` */
+	Rect expand(Rect other) {
+		Rect r;
+		r.pos.x = fminf(pos.x, other.pos.x);
+		r.pos.y = fminf(pos.y, other.pos.y);
+		r.size.x = fmaxf(pos.x + size.x, other.pos.x + other.size.x) - r.pos.x;
+		r.size.y = fmaxf(pos.y + size.y, other.pos.y + other.size.y) - r.pos.y;
+		return r;
+	}
+	/** Returns a Rect with its position set to zero */
+	Rect zeroPos() {
+		Rect r;
+		r.size = size;
+		return r;
+	}
 };
 
 

include/widgets.hpp

@@ -56,8 +56,13 @@ struct Widget {
 
 	virtual ~Widget();
 
-	Vec getAbsolutePos();
 	Rect getChildrenBoundingBox();
+	/**  Returns `v` transformed into the coordinate system of `relative` */
+	virtual Vec getRelativeOffset(Vec v, Widget *relative);
+	/** Returns `v` transformed into world coordinates */
+	Vec getAbsoluteOffset(Vec v) {
+		return getRelativeOffset(v, NULL);
+	}
 	/** Returns a subset of the given Rect bounded by the box of this widget and all ancestors */
 	virtual Rect getViewport(Rect r);
 
@@ -149,6 +154,7 @@ struct TransformWidget : Widget {
 
 struct ZoomWidget : Widget {
 	float zoom = 1.0;
+	Vec getRelativeOffset(Vec v, Widget *relative) override;
 	Rect getViewport(Rect r) override;
 	void setZoom(float zoom);
 	void draw(NVGcontext *vg) override;

src/app/RackScrollWidget.cpp

@@ -6,7 +6,7 @@ namespace rack {
 
 
 void RackScrollWidget::step() {
-	Vec pos = gMousePos.minus(getAbsolutePos());
+	Vec pos = gRackWidget->lastMousePos;
 	// Scroll rack if dragging cable near the edge of the screen
 	if (gRackWidget->wireContainer->activeWire) {
 		float margin = 20.0;

src/app/Toolbar.cpp

@@ -39,7 +39,7 @@ struct QuitItem : MenuItem {
 struct FileChoice : ChoiceButton {
 	void onAction() override {
 		Menu *menu = gScene->createMenu();
-		menu->box.pos = getAbsolutePos().plus(Vec(0, box.size.y));
+		menu->box.pos = getAbsoluteOffset(Vec(0, box.size.y));
 		menu->box.size.x = box.size.x;
 
 		{
@@ -70,7 +70,7 @@ struct SampleRateItem : MenuItem {
 struct SampleRateChoice : ChoiceButton {
 	void onAction() override {
 		Menu *menu = gScene->createMenu();
-		menu->box.pos = getAbsolutePos().plus(Vec(0, box.size.y));
+		menu->box.pos = getAbsoluteOffset(Vec(0, box.size.y));
 		menu->box.size.x = box.size.x;
 
 		PauseItem *pauseItem = new PauseItem();

src/app/WireWidget.cpp

@@ -124,31 +124,27 @@ void WireWidget::updateWire() {
 }
 
 Vec WireWidget::getOutputPos() {
-	Vec pos;
 	if (outputPort) {
-		pos = Rect(outputPort->getAbsolutePos(), outputPort->box.size).getCenter();
+		return outputPort->getRelativeOffset(outputPort->box.zeroPos().getCenter(), gRackWidget);
 	}
 	else if (hoveredOutputPort) {
-		pos = Rect(hoveredOutputPort->getAbsolutePos(), hoveredOutputPort->box.size).getCenter();
+		return hoveredOutputPort->getRelativeOffset(hoveredOutputPort->box.zeroPos().getCenter(), gRackWidget);
 	}
 	else {
 		return gRackWidget->lastMousePos;
 	}
-	return pos.minus(getAbsolutePos().minus(box.pos));
 }
 
 Vec WireWidget::getInputPos() {
-	Vec pos;
 	if (inputPort) {
-		pos = Rect(inputPort->getAbsolutePos(), inputPort->box.size).getCenter();
+		return inputPort->getRelativeOffset(inputPort->box.zeroPos().getCenter(), gRackWidget);
 	}
 	else if (hoveredInputPort) {
-		pos = Rect(hoveredInputPort->getAbsolutePos(), hoveredInputPort->box.size).getCenter();
+		return hoveredInputPort->getRelativeOffset(hoveredInputPort->box.zeroPos().getCenter(), gRackWidget);
 	}
 	else {
 		return gRackWidget->lastMousePos;
 	}
-	return pos.minus(getAbsolutePos().minus(box.pos));
 }
 
 void WireWidget::draw(NVGcontext *vg) {

src/core/AudioInterface.cpp

@@ -335,7 +335,7 @@ struct AudioChoice : ChoiceButton {
 	AudioInterface *audioInterface;
 	void onAction() override {
 		Menu *menu = gScene->createMenu();
-		menu->box.pos = getAbsolutePos().plus(Vec(0, box.size.y));
+		menu->box.pos = getAbsoluteOffset(Vec(0, box.size.y)).round();
 		menu->box.size.x = box.size.x;
 
 		int deviceCount = audioInterface->getDeviceCount();
@@ -373,7 +373,7 @@ struct SampleRateChoice : ChoiceButton {
 	AudioInterface *audioInterface;
 	void onAction() override {
 		Menu *menu = gScene->createMenu();
-		menu->box.pos = getAbsolutePos().plus(Vec(0, box.size.y));
+		menu->box.pos = getAbsoluteOffset(Vec(0, box.size.y)).round();
 		menu->box.size.x = box.size.x;
 
 		const float sampleRates[6] = {44100, 48000, 88200, 96000, 176400, 192000};
@@ -404,7 +404,7 @@ struct BlockSizeChoice : ChoiceButton {
 	AudioInterface *audioInterface;
 	void onAction() override {
 		Menu *menu = gScene->createMenu();
-		menu->box.pos = getAbsolutePos().plus(Vec(0, box.size.y));
+		menu->box.pos = getAbsoluteOffset(Vec(0, box.size.y)).round();
 		menu->box.size.x = box.size.x;
 
 		const int blockSizes[] = {64, 128, 256, 512, 1024, 2048, 4096};

src/core/MidiClockToCV.cpp

@@ -201,7 +201,7 @@ struct ClockRatioChoice : ChoiceButton {
 
 	void onAction() {
 		Menu *menu = gScene->createMenu();
-		menu->box.pos = getAbsolutePos().plus(Vec(0, box.size.y));
+		menu->box.pos = getAbsoluteOffset(Vec(0, box.size.y)).round();
 		menu->box.size.x = box.size.x;
 
 		for (unsigned long ratio = 0; ratio < ratioNames.size(); ratio++) {

src/core/MidiIO.cpp

@@ -182,7 +182,7 @@ void MidiItem::onAction() {
 
 void MidiChoice::onAction() {
 	Menu *menu = gScene->createMenu();
-	menu->box.pos = getAbsolutePos().plus(Vec(0, box.size.y));
+	menu->box.pos = getAbsoluteOffset(Vec(0, box.size.y)).round();
 	menu->box.size.x = box.size.x;
 
 	{
@@ -217,7 +217,7 @@ void ChannelItem::onAction() {
 
 void ChannelChoice::onAction() {
 	Menu *menu = gScene->createMenu();
-	menu->box.pos = getAbsolutePos().plus(Vec(0, box.size.y));
+	menu->box.pos = getAbsoluteOffset(Vec(0, box.size.y)).round();
 	menu->box.size.x = box.size.x;
 
 	{

src/core/QuadMidiToCV.cpp

@@ -259,7 +259,7 @@ struct ModeChoice : ChoiceButton {
 
 	void onAction() {
 		Menu *menu = gScene->createMenu();
-		menu->box.pos = getAbsolutePos().plus(Vec(0, box.size.y));
+		menu->box.pos = getAbsoluteOffset(Vec(0, box.size.y)).round();
 		menu->box.size.x = box.size.x;
 
 		for (unsigned long i = 0; i < modeNames.size(); i++) {

src/widgets/Tooltip.cpp

@@ -6,7 +6,7 @@ namespace rack {
 
 void Tooltip::step() {
 	// Follow the mouse
-	box.pos = gMousePos.minus(parent->getAbsolutePos());
+	box.pos = gMousePos;
 
 	// Wrap size to contents
 	// box.size = getChildrenBoundingBox().getBottomRight();

src/widgets/Widget.cpp

@@ -16,28 +16,28 @@ Widget::~Widget() {
 	clearChildren();
 }
 
-Vec Widget::getAbsolutePos() {
-	// Recursively compute position offset from parents
-	if (!parent) {
-		return box.pos;
-	}
-	else {
-		return box.pos.plus(parent->getAbsolutePos());
+Rect Widget::getChildrenBoundingBox() {
+	Rect bound;
+	for (Widget *child : children) {
+		if (child == children.front()) {
+			bound = child->box;
+		}
+		else {
+			bound = bound.expand(child->box);
+		}
 	}
+	return bound;
 }
 
-Rect Widget::getChildrenBoundingBox() {
-	if (children.empty()) {
-		return Rect();
+Vec Widget::getRelativeOffset(Vec v, Widget *relative) {
+	if (this == relative) {
+		return v;
 	}
-
-	Vec topLeft = Vec(INFINITY, INFINITY);
-	Vec bottomRight = Vec(-INFINITY, -INFINITY);
-	for (Widget *child : children) {
-		topLeft = topLeft.min(child->box.pos);
-		bottomRight = bottomRight.max(child->box.getBottomRight());
+	v = v.plus(box.pos);
+	if (parent) {
+		v = parent->getRelativeOffset(v, relative);
 	}
-	return Rect(topLeft, bottomRight.minus(topLeft));
+	return v;
 }
 
 Rect Widget::getViewport(Rect r) {

src/widgets/ZoomWidget.cpp

@@ -3,6 +3,11 @@
 
 namespace rack {
 
+
+Vec ZoomWidget::getRelativeOffset(Vec v, Widget *relative) {
+	return Widget::getRelativeOffset(v.mult(zoom), relative);
+}
+
 Rect ZoomWidget::getViewport(Rect r) {
 	r.pos = r.pos.mult(zoom);
 	r.size = r.size.mult(zoom);