GUI: Box drawing

src/engine/CommandBuffer.zig

@@ -186,6 +186,10 @@ pub fn copyBufferToImage(
     self.proxy.copyBufferToImage(src_buffer, dst_image, dst_image_layout, regions);
 }
 
+pub fn nextSubpass(self: CommandBuffer, contents: vk.SubpassContents) void {
+    self.proxy.nextSubpass(contents);
+}
+
 pub fn pipelineBarrier(self: CommandBuffer, barrier: PipelineBarrier) void {
     self.proxy.pipelineBarrier(
         barrier.src_stage_mask,