add nanort lib and update external git modules

src/canvas.cpp

@@ -2207,6 +2207,9 @@ void Canvas::draw_objects(std::function<void(const glm::mat4& camera, const glm:
 
         glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, 0);
         layer.m_rtt[i].unbindFramebuffer();
+
+        layer.m_dirty_face[i] = true;
+        layer.m_dirty_box[i] = { 0, 0, layer.w, layer.h };
     }
 
     glDeleteRenderbuffers(1, &rboID);