diff --git a/examples/gravity.cpp b/examples/gravity.cpp
index 593767b1..a7b67534 100644
--- a/examples/gravity.cpp
+++ b/examples/gravity.cpp
@@ -131,7 +131,7 @@ struct myapp : app::app
 		camera_drag_ = std::nullopt;
 	}
 
-	void on_mouse_move(int x, int y) override
+	void on_mouse_move(int x, int y, int, int) override
 	{
 		mouse_ = {x, y};
 
@@ -152,9 +152,6 @@ struct myapp : app::app
 
 		float const dt = 0.01f;
 		float const G = 100.f;
-		float const E = 200.f;
-		float const K = 0.1f;
-		float const C = 0.1f;
 
 		for (std::size_t step = 0; step < 1; ++step)
 		{
@@ -265,7 +262,7 @@ struct myapp : app::app
 		}
 	}
 
-	void draw() override
+	void render() override
 	{
 		gl::Clear(gl::COLOR_BUFFER_BIT);