From 7672a4f06b21a1550f534b7784bb5ddb6136f757 Mon Sep 17 00:00:00 2001
From: thfrwn <11335318+rfht@users.noreply.github.com>
Date: Fri, 30 Aug 2024 08:10:16 -0400
Subject: [PATCH] avoid accessing array at index -1

---
 src/modules/graphics/Polyline.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/modules/graphics/Polyline.cpp b/src/modules/graphics/Polyline.cpp
index e768687c4..90251e68a 100644
--- a/src/modules/graphics/Polyline.cpp
+++ b/src/modules/graphics/Polyline.cpp
@@ -100,7 +100,7 @@ void Polyline::render(const Vector2 *coords, size_t count, size_t size_hint, flo
 	}
 
 	// Add the degenerate triangle strip.
-	if (extra_vertices)
+	if (extra_vertices && vertex_count > 0)
 	{
 		vertices[vertex_count + 0] = vertices[vertex_count - 1];
 		vertices[vertex_count + 1] = vertices[overdraw_vertex_start];