Set cull mode to None so that the shape doesn't disappear when the camera is on its back

code/beginner/tutorial6-uniforms/src/lib.rs

@@ -419,7 +419,7 @@ impl State {
                 topology: wgpu::PrimitiveTopology::TriangleList,
                 strip_index_format: None,
                 front_face: wgpu::FrontFace::Ccw,
-                cull_mode: Some(wgpu::Face::Back),
+                cull_mode: None,
                 // Setting this to anything other than Fill requires Features::POLYGON_MODE_LINE
                 // or Features::POLYGON_MODE_POINT
                 polygon_mode: wgpu::PolygonMode::Fill,