diff --git a/android/src/cpp/main.cpp b/android/src/cpp/main.cpp
index 119a373..82e9d53 100644
--- a/android/src/cpp/main.cpp
+++ b/android/src/cpp/main.cpp
@@ -62,7 +62,7 @@ EGLContext g_context = EGL_NO_CONTEXT;
 std::recursive_mutex mutex;
 int mutex_count = 0;
 struct engine g_engine;
-JNIEnv* jni;
+thread_local JNIEnv* jni;
 
 jint JNI_OnLoad(JavaVM* vm, void* /*reserved*/)
 {
@@ -118,6 +118,16 @@ int GetUnicodeChar(struct android_app* app, int eventType, int keyCode, int meta
     return unicodeKey;
 }
 
+void android_attach_jni()
+{
+    g_engine.app->activity->vm->AttachCurrentThread(&jni, nullptr);
+}
+
+void android_detach_jni()
+{
+    g_engine.app->activity->vm->DetachCurrentThread();
+}
+
 void android_async_lock(struct engine* engine)
 {
     mutex.lock();
diff --git a/src/app.cpp b/src/app.cpp
index 8a5d7f1..4034b4a 100644
--- a/src/app.cpp
+++ b/src/app.cpp
@@ -15,6 +15,8 @@
 void android_async_lock(struct engine* engine);
 void android_async_swap(struct engine* engine);
 void android_async_unlock(struct engine* engine);
+void android_attach_jni();
+void android_detach_jni();
 #elif _WIN32
 bool async_lock_try();
 void async_lock();
@@ -853,6 +855,10 @@ void App::ui_thread_main()
     ui_thread_id = std::this_thread::get_id();
     ui_running = true;
 
+#if __ANDROID__
+    android_attach_jni();
+#endif
+
     init();
 
     auto t_start = std::chrono::high_resolution_clock::now();
@@ -922,6 +928,9 @@ void App::ui_thread_main()
             rendered_frames++;
         }
     }
+#if __ANDROID__
+    android_detach_jni();
+#endif
 }
 
 void App::render_thread_start()
diff --git a/src/canvas.cpp b/src/canvas.cpp
index 8482c17..8efcfc3 100644
--- a/src/canvas.cpp
+++ b/src/canvas.cpp
@@ -1395,7 +1395,8 @@ void Canvas::flood_fill(int layer, int plane, std::vector<glm::ivec2> pos, Flood
                     rgb[i] = dest_color * 255.f;
                     plane_data.dirty[plane] = true;
                     glm::vec2 bb_min = glm::min((glm::vec2)p, xy(plane_data.bb[plane]));
-                    glm::vec2 bb_max = glm::max((glm::vec2)p, zw(plane_data.bb[plane]));
+                    // add 1 pixel to the end because 1 pixel has min(0) and max(1)
+                    glm::vec2 bb_max = glm::max((glm::vec2)p + glm::vec2(1), zw(plane_data.bb[plane]));
                     plane_data.bb[plane] = { bb_min, bb_max };
                 }
                 pos.push_back(p);