diff --git a/CHANGELOG.md b/CHANGELOG.md
index 86d6123c..365214ba 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
     * Added Inflate/Deflate modifier (aka Pucker/Bloat)
     * Added support for rounded polygons / stars
     * Added rounded corners modifier
+    * Added support for inverted masks
 * I/O:
     * Loading Lottie with `meta` no longer show a warning
     * Fixed UUIDs when loading lottie animations
@@ -17,6 +18,7 @@
     * Fixed parsing SVG paths
     * Added support for loading basic animated SVG paths
     * Fixed importing solid layers from lottie
+    * Fixed importing mattes affecting precomps
 * UI:
     * Added simplified Chinese translation
     * Added British English translation
diff --git a/src/core/io/glaxnimate/glaxnimate_format.cpp b/src/core/io/glaxnimate/glaxnimate_format.cpp
index abc53d70..17e6f82d 100644
--- a/src/core/io/glaxnimate/glaxnimate_format.cpp
+++ b/src/core/io/glaxnimate/glaxnimate_format.cpp
@@ -11,7 +11,7 @@ using namespace glaxnimate;
 
 io::Autoreg<io::glaxnimate::GlaxnimateFormat> io::glaxnimate::GlaxnimateFormat::autoreg;
 
-const int glaxnimate::io::glaxnimate::GlaxnimateFormat::format_version = 5;
+const int glaxnimate::io::glaxnimate::GlaxnimateFormat::format_version = 6;
 
 
 
diff --git a/src/core/io/glaxnimate/import_state.hpp b/src/core/io/glaxnimate/import_state.hpp
index 4ff17182..70e22e94 100644
--- a/src/core/io/glaxnimate/import_state.hpp
+++ b/src/core/io/glaxnimate/import_state.hpp
@@ -226,6 +226,12 @@ class ImportState
                     object["multiple"] = "Individually";
             }
         }
+
+        if ( document_version < 6 )
+        {
+            if ( object["__type__"].toString() == "MaskSettings" )
+                object["mask"] = int(object["mask"].toBool());
+        }
     }
 
     void do_load_object ( model::Object* target, QJsonObject object, const UnresolvedPath& path )
diff --git a/src/core/io/lottie/lottie_importer.hpp b/src/core/io/lottie/lottie_importer.hpp
index d7b3b240..9f11e499 100644
--- a/src/core/io/lottie/lottie_importer.hpp
+++ b/src/core/io/lottie/lottie_importer.hpp
@@ -10,6 +10,8 @@
 #include "lottie_private_common.hpp"
 #include "io/svg/svg_parser.hpp"
 
+#include <QDebug>
+
 namespace glaxnimate::io::lottie::detail {
 
 struct FontInfo
@@ -123,11 +125,6 @@ class LottieImporterState
             load_layer(pair.second, static_cast<model::Layer*>(pair.first));
     }
 
-    bool has_mask(const QJsonObject& json)
-    {
-        return mask && json["tt"].toInt();
-    }
-
     void load_visibility(model::VisualNode* node, const QJsonObject& json)
     {
         if ( json.contains("hd") && json["hd"].toBool() )
@@ -145,39 +142,63 @@ class LottieImporterState
         }
 
         int ty = json["ty"].toInt();
+
+        std::unique_ptr<model::ShapeElement> inner_shape;
+        bool start_mask = json["td"].toInt();
+
         if ( ty == 0 )
         {
-            load_precomp_layer(json, referenced);
-            mask = nullptr;
+            inner_shape = load_precomp_layer(json);
+
+            auto op = document->main()->animation->last_frame.get();
+            if ( json.contains("parent") || referenced.count(index) || json["ip"].toDouble() != 0 ||
+                json["op"].toDouble(op) != op || start_mask
+            )
+            {
+                auto layer = make_node<model::Layer>(document);
+                layer->name.set(inner_shape->name.get());
+                layer->shapes.insert(std::move(inner_shape), 0);
+                layer_indices[index] = layer.get();
+                deferred.emplace_back(layer.get(), json);
+                inner_shape = std::move(layer);
+            }
         }
         else
         {
             auto layer = std::make_unique<model::Layer>(document);
-            if ( json["td"].toInt() )
+            layer_indices[index] = layer.get();
+            deferred.emplace_back(layer.get(), json);
+            inner_shape = std::move(layer);
+        }
+
+        if ( start_mask )
+        {
+            auto layer = std::make_unique<model::Layer>(document);
+            mask = layer.get();
+            layer->name.set(json["nm"].toString());
+            layer->shapes.insert(std::move(inner_shape), 0);
+            composition->shapes.insert(std::move(layer), 0);
+        }
+        else
+        {
+            auto tt = json["tt"].toInt();
+
+            if ( mask && tt )
             {
-                mask = layer.get();
-                layer->mask->mask.set(true);
-                layer->name.set(json["nm"].toString());
-                auto child = std::make_unique<model::Layer>(document);
-                layer_indices[index] = child.get();
-                deferred.emplace_back(child.get(), json);
-                layer->shapes.insert(std::move(child), 0);
-                composition->shapes.insert(std::move(layer), 0);
+                mask->shapes.insert(std::move(inner_shape), 1);
+                auto mode = model::MaskSettings::MaskMode((tt + 1) / 2);
+                mask->mask->mask.set(mode);
+                mask->mask->inverted.set(tt > 0 && tt % 2 == 0);
             }
             else
             {
-                layer_indices[index] = layer.get();
-                deferred.emplace_back(layer.get(), json);
-                if ( has_mask(json) )
-                    mask->shapes.insert(std::move(layer), 1);
-                else
-                    composition->shapes.insert(std::move(layer), 0);
-                mask = nullptr;
+                composition->shapes.insert(std::move(inner_shape), 0);
             }
+            mask = nullptr;
         }
     }
 
-    void load_precomp_layer(const QJsonObject& json, std::set<int>& referenced)
+    std::unique_ptr<model::PreCompLayer> load_precomp_layer(const QJsonObject& json)
     {
         auto props = load_basic_setup(json);
 
@@ -211,27 +232,9 @@ class LottieImporterState
             json["h"].toInt()
         ));
 
-        int index = json["ind"].toInt();
-        auto op = document->main()->animation->last_frame.get();
-        if ( json.contains("parent") || referenced.count(index) || json["ip"].toDouble() != 0 ||
-            json["op"].toDouble(op) != op || has_mask(json)
-        )
-        {
-            auto layer = make_node<model::Layer>(document);
-            layer->name.set(precomp->name.get());
-            layer->shapes.insert(std::move(precomp), 0);
-            if ( has_mask(json) )
-                layer->mask->mask.set(mask);
-            layer_indices[index] = layer.get();
-            deferred.emplace_back(layer.get(), json);
-            load_transform(json["ks"].toObject(), layer->transform.get(), &layer->opacity);
-            composition->shapes.insert(std::move(layer), 0);
-        }
-        else
-        {
-            load_transform(json["ks"].toObject(), precomp->transform.get(), &precomp->opacity);
-            composition->shapes.insert(std::move(precomp), 0);
-        }
+        load_transform(json["ks"].toObject(), precomp->transform.get(), &precomp->opacity);
+
+        return precomp;
     }
 
     void load_mask(const QJsonObject& json, model::Group* group)
@@ -318,7 +321,7 @@ class LottieImporterState
             auto masks = json["masksProperties"].toArray();
             if ( !masks.empty() )
             {
-                layer->mask->mask.set(true);
+                layer->mask->mask.set(model::MaskSettings::Alpha);
 
                 auto clip_p = make_node<model::Group>(document);
                 auto clip = clip_p.get();
diff --git a/src/core/io/svg/svg_parser.cpp b/src/core/io/svg/svg_parser.cpp
index 93671da7..20d1b3c3 100644
--- a/src/core/io/svg/svg_parser.cpp
+++ b/src/core/io/svg/svg_parser.cpp
@@ -574,7 +574,7 @@ class glaxnimate::io::svg::SvgParser::Private
         auto layer = std::make_unique<model::Layer>(document);
         apply_common_style(layer.get(), args.element, style);
         set_name(layer.get(), args.element);
-        layer->mask->mask.set(true);
+        layer->mask->mask.set(model::MaskSettings::Alpha);
 
         QDomElement element = args.element;
 
diff --git a/src/core/model/mask_settings.hpp b/src/core/model/mask_settings.hpp
index 14b5dd45..17347c25 100644
--- a/src/core/model/mask_settings.hpp
+++ b/src/core/model/mask_settings.hpp
@@ -11,8 +11,16 @@ class MaskSettings : public Object
 {
     GLAXNIMATE_OBJECT(MaskSettings)
 
-    GLAXNIMATE_PROPERTY(bool, mask, false, {}, {}, PropertyTraits::Visual)
-//     GLAXNIMATE_PROPERTY(bool, invert, false, {}, {}, PropertyTraits::Visual)
+public:
+    enum MaskMode
+    {
+        NoMask = 0,
+        Alpha = 1,
+    };
+    Q_ENUM(MaskMode)
+
+    GLAXNIMATE_PROPERTY(MaskMode, mask, NoMask, {}, {}, PropertyTraits::Visual)
+    GLAXNIMATE_PROPERTY(bool, inverted, false, {}, {}, PropertyTraits::Visual)
 
 public:
     using Object::Object;
diff --git a/src/core/model/shapes/layer.cpp b/src/core/model/shapes/layer.cpp
index 2fb4389e..e29c91c6 100644
--- a/src/core/model/shapes/layer.cpp
+++ b/src/core/model/shapes/layer.cpp
@@ -3,6 +3,7 @@
 #include <QPainter>
 
 #include "model/composition.hpp"
+#include "model/document.hpp"
 
 GLAXNIMATE_OBJECT_IMPL(glaxnimate::model::Layer)
 
@@ -124,6 +125,14 @@ void glaxnimate::model::Layer::paint(QPainter* painter, FrameTime time, PaintMod
         {
             QPainterPath clip = shapes[0]->to_clip(time);
             clip.setFillRule(Qt::WindingFill);
+            if ( mask->inverted.get() )
+            {
+                QPainterPath outer_clip;
+                outer_clip.addPolygon(
+                    transform.inverted().map(QRectF(QPointF(0, 0), document()->size()))
+                );
+                clip = outer_clip.subtracted(clip);
+            }
             painter->setClipPath(clip, Qt::IntersectClip);
         }
 
diff --git a/src/python/miscdefs.cpp b/src/python/miscdefs.cpp
index 809bfdd8..7279a574 100644
--- a/src/python/miscdefs.cpp
+++ b/src/python/miscdefs.cpp
@@ -103,7 +103,7 @@ static void define_trace(py::module& m)
     py::class_<TraceOptions>(trace, "TraceOptions")
         .def(py::init<>())
         .def_property("smoothness", &TraceOptions::smoothness, &TraceOptions::set_smoothness)
-        .def_property("min_area", &TraceOptions::min_area, &TraceOptions::min_area)
+        .def_property("min_area", &TraceOptions::min_area, &TraceOptions::set_min_area)
     ;
     py::class_<Tracer>(trace, "Tracer")
         .def(py::init<const QImage&, const TraceOptions&>())