Guard and attack markers (shields and swords, up to eight each, right click removes); the world and the interface are copied opaque so glows keep their brightness

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/ui.rs

@@ -24,6 +24,7 @@ thread_local! {
     static UI_TARGET: std::cell::RefCell<Option<(RenderTarget, u32, u32)>> = std::cell::RefCell::new(None);
     static UP_TARGET: std::cell::RefCell<Option<(RenderTarget, u32, u32)>> = std::cell::RefCell::new(None);
     static FRAME_STARTED: std::cell::Cell<bool> = std::cell::Cell::new(false);
+    static OPAQUE: std::cell::RefCell<Option<Material>> = std::cell::RefCell::new(None);
 }
 
 // the rows of the virtual screen for this frame (0: device pixels). Set once per frame before
@@ -188,7 +189,16 @@ pub fn end_frame() {
     c.render_target = Some(up.clone());
     set_camera(&c);
     clear_background(Color::new(0.0, 0.0, 0.0, 1.0));
+    // opaque: translucent parts must not let the black below shine through
+    OPAQUE.with(|m| {
+        let mut m = m.borrow_mut();
+        if m.is_none() {
+            *m = Some(crate::render3d::opaque_material());
+        }
+        gl_use_material(m.as_ref().unwrap());
+    });
     draw_texture_ex(&rt.texture, 0.0, 0.0, WHITE, DrawTextureParams { dest_size: Some(vec2(uw as f32, uh as f32)), flip_y: true, ..Default::default() });
+    gl_use_default_material();
     set_default_camera();
     draw_texture_ex(&up.texture, 0.0, 0.0, WHITE, DrawTextureParams { dest_size: Some(vec2(screen_width(), screen_height())), flip_y: true, ..Default::default() });
 }