diff -r 0f221121849b -r 4585d8d7a7ec src/ui/canvas.cpp
--- a/src/ui/canvas.cpp	Thu Feb 27 14:38:58 2020 +0200
+++ b/src/ui/canvas.cpp	Thu Feb 27 22:46:39 2020 +0200
@@ -7,7 +7,8 @@
 	DocumentManager* documents,
 	const ldraw::ColorTable& colorTable,
 	QWidget* parent) :
-	PartRenderer{model, documents, colorTable, parent}
+	PartRenderer{model, documents, colorTable, parent},
+	gridProgram{this}
 {
 	this->setMouseTracking(true);
 }
@@ -21,13 +22,20 @@
 	this->update();
 }
 
+QString vectorToString(const glm::vec3& vec)
+{
+	return "(%1, %2, %3)"_q
+		.arg(toDouble(vec.x))
+		.arg(toDouble(vec.y))
+		.arg(toDouble(vec.z));
+}
+
 void Canvas::mouseMoveEvent(QMouseEvent* event)
 {
 	const ldraw::Id id = this->pick(event->pos());
 	this->highlighted = id;
 	this->totalMouseMove += (event->pos() - this->lastMousePosition).manhattanLength();
-	this->lastMousePosition = event->pos();
-	this->worldPosition = this->screenToModelCoordinates(this->lastMousePosition, geom::XY);
+	this->worldPosition = this->screenToModelCoordinates(event->pos(), geom::XY);
 	if (this->worldPosition.has_value())
 	{
 		this->worldPosition = glm::round(*this->worldPosition);
@@ -35,9 +43,9 @@
 	if (this->worldPosition.has_value())
 	{
 		this->newStatusText("Position: (%1, %2, %3)"_q
-			.arg(this->worldPosition->x)
-			.arg(this->worldPosition->y)
-			.arg(this->worldPosition->z));
+			.arg(toDouble(this->worldPosition->x))
+			.arg(toDouble(this->worldPosition->y))
+			.arg(toDouble(this->worldPosition->z)));
 	}
 	else
 	{
@@ -72,15 +80,51 @@
 	PartRenderer::mouseReleaseEvent(event);
 }
 
+void Canvas::initializeGL()
+{
+	// We first create the grid program and connect everything and only then call the part renderer's initialization
+	// functions so that when initialization sets up, the signals also set up the matrices on our side.
+	this->gridProgram.emplace(this);
+	this->gridProgram->initialize();
+	connect(this, &PartRenderer::projectionMatrixChanged, [&]()
+	{
+		this->gridProgram->setProjectionMatrix(this->projectionMatrix);
+	});
+	connect(this, &PartRenderer::modelMatrixChanged, [&]()
+	{
+		this->gridProgram->setModelMatrix(this->modelMatrix);
+	});
+	connect(this, &PartRenderer::viewMatrixChanged, [&]()
+	{
+		this->gridProgram->setViewMatrix(this->viewMatrix);
+	});
+	connect(this, &PartRenderer::renderPreferencesChanged, [&]()
+	{
+		if (this->gridProgram.has_value())
+		{
+			const bool isDark = luma(this->renderPreferences.backgroundColor) < 0.25;
+			this->gridProgram->setGridColor(isDark ? Qt::white : Qt::black);
+		}
+	});
+	PartRenderer::initializeGL();
+}
+
 void Canvas::paintGL()
 {
 	PartRenderer::paintGL();
+	glEnable(GL_BLEND);
+	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+	this->gridProgram->draw();
+	glDisable(GL_BLEND);
 	if (this->worldPosition.has_value())
 	{
 		QPainter painter{this};
 		painter.setRenderHint(QPainter::Antialiasing);
 		painter.setPen(Qt::black);
 		painter.setBrush(Qt::green);
-		painter.drawEllipse(this->modelToScreenCoordinates(*this->worldPosition), 10, 10);
+		const QPointF pos = this->modelToScreenCoordinates(*this->worldPosition);
+		painter.drawEllipse(pos, 5, 5);
+		painter.setPen(Qt::white);
+		painter.drawText(pos + QPointF{5, 5}, vectorToString(*this->worldPosition));
 	}
 }