Use another nanovg context for rendering to the framebuffer

include/gui.hpp

@@ -17,6 +17,7 @@ namespace rack {
 
 extern GLFWwindow *gWindow;
 extern NVGcontext *gVg;
+extern NVGcontext *gFramebufferVg;
 extern std::shared_ptr<Font> gGuiFont;
 extern float gPixelRatio;
 extern bool gAllowCursorLock;

include/widgets.hpp

@@ -228,7 +228,6 @@ struct FramebufferWidget : virtual Widget {
 
 	FramebufferWidget();
 	~FramebufferWidget();
-	void step() override;
 	void draw(NVGcontext *vg) override;
 	int getImageHandle();
 };

src/app/RackScene.cpp

@@ -31,7 +31,7 @@ RackScene::RackScene() {
 	scrollWidget = new RackScrollWidget();
 	{
 		zoomWidget = new ZoomWidget();
-		zoomWidget->zoom = 1.0;
+		zoomWidget->zoom = 0.5;
 		{
 			assert(!gRackWidget);
 			gRackWidget = new RackWidget();

src/app/RackWidget.cpp

@@ -404,6 +404,9 @@ struct AddManufacturerMenuItem : MenuItem {
 		for (Model *model : models) {
 			AddModuleMenuItem *item = new AddModuleMenuItem();
 			item->text = model->name;
+			// item->rightText = model->plugin->slug;
+			// if (!model->plugin->version.empty())
+			// 	item->rightText += " v" + model->plugin->version;
 			item->model = model;
 			item->modulePos = modulePos;
 			menu->pushChild(item);

src/gui.cpp

@@ -29,6 +29,7 @@ namespace rack {
 
 GLFWwindow *gWindow = NULL;
 NVGcontext *gVg = NULL;
+NVGcontext *gFramebufferVg = NULL;
 std::shared_ptr<Font> gGuiFont;
 float gPixelRatio = 0.0;
 bool gAllowCursorLock = true;
@@ -220,15 +221,15 @@ void renderGui() {
 	gPixelRatio = (float)width / windowWidth;
 
 	// Update and render
-	glViewport(0, 0, width, height);
-	glClearColor(0.0, 0.0, 0.0, 1.0);
-	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
 	nvgBeginFrame(gVg, width, height, gPixelRatio);
 
 	nvgReset(gVg);
 	nvgScale(gVg, gPixelRatio, gPixelRatio);
 	gScene->draw(gVg);
 
+	glViewport(0, 0, width, height);
+	glClearColor(0.0, 0.0, 0.0, 1.0);
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
 	nvgEndFrame(gVg);
 	glfwSwapBuffers(gWindow);
 }
@@ -288,6 +289,9 @@ void guiInit() {
 	// gVg = nvgCreateGL3(NVG_ANTIALIAS);
 	assert(gVg);
 
+	gFramebufferVg = nvgCreateGL2(NVG_ANTIALIAS);
+	assert(gFramebufferVg);
+
 	// Set up Blendish
 	gGuiFont = Font::load(assetGlobal("res/DejaVuSans.ttf"));
 	bndSetFont(gGuiFont->handle);
@@ -298,6 +302,7 @@ void guiDestroy() {
 	gGuiFont.reset();
 	nvgDeleteGL2(gVg);
 	// nvgDeleteGL3(gVg);
+	nvgDeleteGL2(gFramebufferVg);
 	glfwDestroyWindow(gWindow);
 	glfwTerminate();
 }

src/widgets/FramebufferWidget.cpp

@@ -32,11 +32,7 @@ FramebufferWidget::~FramebufferWidget() {
 	delete internal;
 }
 
-void FramebufferWidget::step() {
-	// Step children before rendering
-	Widget::step();
-
-	// Render the scene to the framebuffer if dirty
+void FramebufferWidget::draw(NVGcontext *vg) {
 	if (dirty) {
 		internal->box.pos = Vec(0, 0);
 		internal->box.size = box.size;
@@ -50,6 +46,7 @@ void FramebufferWidget::step() {
 
 		// Delete old one first to free up GPU memory
 		internal->setFramebuffer(NULL);
+		// Create a framebuffer from the main nanovg context. We will draw to this in the secondary nanovg context.
 		NVGLUframebuffer *fb = nvgluCreateFramebuffer(gVg, fbSize.x, fbSize.y, NVG_IMAGE_REPEATX | NVG_IMAGE_REPEATY);
 		if (!fb)
 			return;
@@ -59,36 +56,19 @@ void FramebufferWidget::step() {
 		glViewport(0.0, 0.0, fbSize.x, fbSize.y);
 		glClearColor(0.0, 0.0, 0.0, 0.0);
 		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
-		nvgBeginFrame(gVg, fbSize.x, fbSize.y, gPixelRatio * oversample);
 
-		nvgScale(gVg, gPixelRatio * oversample, gPixelRatio * oversample);
-		Widget::draw(gVg);
+		nvgBeginFrame(gFramebufferVg, fbSize.x, fbSize.y, gPixelRatio * oversample);
 
-		nvgEndFrame(gVg);
+		nvgScale(gFramebufferVg, gPixelRatio * oversample, gPixelRatio * oversample);
+		Widget::draw(gFramebufferVg);
+
+		nvgEndFrame(gFramebufferVg);
 		nvgluBindFramebuffer(NULL);
 
 		dirty = false;
 	}
-}
-
-void FramebufferWidget::draw(NVGcontext *vg) {
-	// {
-	// 	float xform[6];
-	// 	nvgCurrentTransform(vg, xform);
-	// 	printf("%f %f %f %f %f %f\n", xform[0], xform[1], xform[2], xform[3], xform[4], xform[5]);
-	// 	nvgSave(vg);
-	// 	nvgResetTransform(vg);
-	// 	nvgTranslate(vg, xform[5], xform[6]);
-	// 	nvgBeginPath(vg);
-	// 	nvgRect(vg, 0, 0, 50, 50);
-	// 	nvgFillColor(vg, nvgRGBf(1.0, 0.0, 0.0));
-	// 	nvgFill(vg);
-	// 	nvgRestore(vg);
-	// }
 
 	if (!internal->fb) {
-		// Bypass framebuffer cache entirely
-		// Widget::draw(vg);
 		return;
 	}
 
@@ -102,6 +82,22 @@ void FramebufferWidget::draw(NVGcontext *vg) {
 	// For debugging bounding box of framebuffer image
 	// nvgFillColor(vg, nvgRGBA(255, 0, 0, 64));
 	// nvgFill(vg);
+
+	{
+		float xform[6];
+		nvgCurrentTransform(vg, xform);
+		// printf("%f %f %f %f; %f %f\n", xform[0], xform[1], xform[2], xform[3], xform[4], xform[5]);
+		nvgSave(vg);
+		nvgResetTransform(vg);
+		nvgTranslate(vg, xform[4], xform[5]);
+		nvgScale(vg, xform[0], xform[3]);
+		nvgBeginPath(vg);
+		nvgRect(vg, 0, 0, internal->box.size.x, internal->box.size.y);
+		nvgStrokeWidth(vg, 2.0);
+		nvgStrokeColor(vg, nvgRGBf(1.0, 0.0, 0.0));
+		nvgStroke(vg);
+		nvgRestore(vg);
+	}
 }
 
 int FramebufferWidget::getImageHandle() {