From a51226bebbb8bf8ab77f1ad55f1c7fac99226db7 Mon Sep 17 00:00:00 2001
From: iforce2d <iforce2d@gmail.com>
Date: Sun, 14 Dec 2025 12:19:07 +1300
Subject: [PATCH] Preserve world position of mouse cursor after scroll zoom in
 samples app

---
 samples/main.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/samples/main.cpp b/samples/main.cpp
index 9725daf53..3da3c41c4 100644
--- a/samples/main.cpp
+++ b/samples/main.cpp
@@ -378,6 +378,11 @@ static void ScrollCallback( GLFWwindow* window, double dx, double dy )
 		return;
 	}
 
+	double xd, yd;
+	glfwGetCursorPos( window, &xd, &yd );
+	b2Vec2 ps = { float( xd ), float( yd ) };
+	b2Vec2 pwBefore = ConvertScreenToWorld( &s_context.camera, ps );
+
 	if ( dy > 0 )
 	{
 		s_context.camera.zoom /= 1.1f;
@@ -386,6 +391,10 @@ static void ScrollCallback( GLFWwindow* window, double dx, double dy )
 	{
 		s_context.camera.zoom *= 1.1f;
 	}
+
+	b2Vec2 pwAfter = ConvertScreenToWorld( &s_context.camera, ps );
+	b2Vec2 delta = pwAfter - pwBefore;
+	s_context.camera.center -= delta;
 }
 
 static void UpdateUI()