From 88b109bae6e453796b2fc8546dee4d12fd767d3e Mon Sep 17 00:00:00 2001
From: Alessandro Iezzi <aiezzi@alessandroiezzi.it>
Date: Mon, 19 May 2025 16:06:12 +0200
Subject: Add logic to maintain the aspect ratio

---
 src/main/engine/engine.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

(limited to 'src/main/engine/engine.c')

diff --git a/src/main/engine/engine.c b/src/main/engine/engine.c
index b4d70b0..08823a6 100644
--- a/src/main/engine/engine.c
+++ b/src/main/engine/engine.c
@@ -153,9 +153,27 @@ draw_frames()
 	engine_calculate_fps();
 }
 
+static void
+engine_on_ui_expose(UIEventResize *er)
+{
+	/* Set the viewport to the window size */
+	glViewport(0, 0, er->width, er->height);
+
+	/* Objects in the rendering area must maintain the proportions. So, let's enable Ortho */
+	glMatrixMode(GL_PROJECTION);
+	glLoadIdentity();
+	float aspect = (float)er->width / (float)er->height;
+	glOrtho(-aspect, aspect, -1, 1, -1, 1);
+
+	/* Returns to the model view */
+	glMatrixMode(GL_MODELVIEW);
+	glLoadIdentity();
+}
+
 void
 engine_loop(void)
 {
+	ui_set_resize_listener(engine_on_ui_expose);
 	ui_set_loop_listener(draw_frames);
 
 	/* FPS calculation */
-- 
cgit v1.2.3