diff --git a/map-tool/src/source.rs b/map-tool/src/source.rs
index 4f1e3de..fc0ff51 100644
--- a/map-tool/src/source.rs
+++ b/map-tool/src/source.rs
@@ -165,8 +165,8 @@ fn load_texture<'bsp,'vpk,'a>(finder:BspFinder<'bsp,'vpk>,texture_name:&str)->Re
 {
 	let mut texture_file_name=PathBuf::from("materials");
 	//lower case
-	let texture_file_name_lowercase=texture_name.to_lowercase();
-	texture_file_name.push(texture_file_name_lowercase.clone());
+	texture_file_name.push(texture_name);
+	texture_file_name.as_mut_os_str().make_ascii_lowercase();
 	//remove stem and search for both vtf and vmt files
 	let stem=texture_file_name.file_stem().unwrap().to_owned();
 	texture_file_name.pop();