[node] Don't needlessly reset map state

1 files changed, 41 insertions, 19 deletions

diff --git a/platform/node/src/node_map.cpp b/platform/node/src/node_map.cpp
index e630275ec0..c58a450295 100644
--- a/platform/node/src/node_map.cpp
+++ b/platform/node/src/node_map.cpp
@@ -21,15 +21,15 @@
 namespace node_mbgl {
 
 struct NodeMap::RenderOptions {
-    double zoom = 0;
-    double bearing = 0;
-    double pitch = 0;
-    double latitude = 0;
-    double longitude = 0;
+    mbgl::optional<double> zoom;
+    mbgl::optional<double> bearing;
+    mbgl::optional<double> pitch;
+    mbgl::optional<double> latitude;
+    mbgl::optional<double> longitude;
     unsigned int width = 512;
     unsigned int height = 512;
-    std::vector<std::string> classes;
-    mbgl::MapDebugOptions debugOptions = mbgl::MapDebugOptions::NoDebug;
+    mbgl::optional<std::vector<std::string>> classes;
+    mbgl::optional<mbgl::MapDebugOptions> debugOptions;
 };
 
 Nan::Persistent<v8::Function> NodeMap::constructor;
@@ -266,37 +266,40 @@ NodeMap::RenderOptions NodeMap::ParseOptions(v8::Local<v8::Object> obj) {
     if (Nan::Has(obj, Nan::New("classes").ToLocalChecked()).FromJust()) {
         auto classes = Nan::To<v8::Object>(Nan::Get(obj, Nan::New("classes").ToLocalChecked()).ToLocalChecked()).ToLocalChecked().As<v8::Array>();
         const int length = classes->Length();
-        options.classes.reserve(length);
+        std::vector<std::string> vector;
+        vector.reserve(length);
         for (int i = 0; i < length; i++) {
-            options.classes.push_back(std::string { *Nan::Utf8String(Nan::To<v8::String>(Nan::Get(classes, i).ToLocalChecked()).ToLocalChecked()) });
+            vector.push_back(std::string { *Nan::Utf8String(Nan::To<v8::String>(Nan::Get(classes, i).ToLocalChecked()).ToLocalChecked()) });
         }
+        options.classes = std::move(vector);
     }
 
     if (Nan::Has(obj, Nan::New("debug").ToLocalChecked()).FromJust()) {
         auto debug = Nan::To<v8::Object>(Nan::Get(obj, Nan::New("debug").ToLocalChecked()).ToLocalChecked()).ToLocalChecked();
+        options.debugOptions = mbgl::MapDebugOptions::NoDebug;
         if (Nan::Has(debug, Nan::New("tileBorders").ToLocalChecked()).FromJust()) {
             if (Nan::Get(debug, Nan::New("tileBorders").ToLocalChecked()).ToLocalChecked()->BooleanValue()) {
-                options.debugOptions = options.debugOptions | mbgl::MapDebugOptions::TileBorders;
+                *options.debugOptions = *options.debugOptions | mbgl::MapDebugOptions::TileBorders;
             }
         }
         if (Nan::Has(debug, Nan::New("parseStatus").ToLocalChecked()).FromJust()) {
             if (Nan::Get(debug, Nan::New("parseStatus").ToLocalChecked()).ToLocalChecked()->BooleanValue()) {
-                options.debugOptions = options.debugOptions | mbgl::MapDebugOptions::ParseStatus;
+                *options.debugOptions = *options.debugOptions | mbgl::MapDebugOptions::ParseStatus;
             }
         }
         if (Nan::Has(debug, Nan::New("timestamps").ToLocalChecked()).FromJust()) {
             if (Nan::Get(debug, Nan::New("timestamps").ToLocalChecked()).ToLocalChecked()->BooleanValue()) {
-                options.debugOptions = options.debugOptions | mbgl::MapDebugOptions::Timestamps;
+                *options.debugOptions = *options.debugOptions | mbgl::MapDebugOptions::Timestamps;
             }
         }
         if (Nan::Has(debug, Nan::New("collision").ToLocalChecked()).FromJust()) {
             if (Nan::Get(debug, Nan::New("collision").ToLocalChecked()).ToLocalChecked()->BooleanValue()) {
-                options.debugOptions = options.debugOptions | mbgl::MapDebugOptions::Collision;
+                *options.debugOptions = *options.debugOptions | mbgl::MapDebugOptions::Collision;
             }
         }
         if (Nan::Has(debug, Nan::New("overdraw").ToLocalChecked()).FromJust()) {
             if (Nan::Get(debug, Nan::New("overdraw").ToLocalChecked()).ToLocalChecked()->BooleanValue()) {
-                options.debugOptions = mbgl::MapDebugOptions::Overdraw;
+                *options.debugOptions = mbgl::MapDebugOptions::Overdraw;
             }
         }
     }
@@ -364,11 +367,30 @@ void NodeMap::startRender(NodeMap::RenderOptions options) {
         view.reset();
         view = std::make_unique<mbgl::OffscreenView>(backend.getContext(), fbSize);
     }
-    map->setClasses(options.classes);
-    map->setLatLngZoom(mbgl::LatLng(options.latitude, options.longitude), options.zoom);
-    map->setBearing(options.bearing);
-    map->setPitch(options.pitch);
-    map->setDebug(options.debugOptions);
+
+    if (options.classes) {
+        map->setClasses(*options.classes);
+    }
+
+    if (options.latitude && options.longitude) {
+        map->setLatLng(mbgl::LatLng(*options.latitude, *options.longitude));
+    }
+
+    if (options.zoom) {
+        map->setZoom(*options.zoom);
+    }
+
+    if (options.bearing) {
+        map->setBearing(*options.bearing);
+    }
+
+    if (options.pitch) {
+        map->setPitch(*options.pitch);
+    }
+
+    if (options.debugOptions) {
+        map->setDebug(*options.debugOptions);
+    }
 
     map->renderStill(*view, [this](const std::exception_ptr eptr) {
         if (eptr) {