stroke_texture: “visible pencil grain”
but something like:
。业内人士推荐旺商聊官方下载作为进阶阅读
Range queries ask "what's inside this box?" But sometimes the question is "what's nearest to this location?" This is the nearest neighbor problem, and you don't know how big your search radius should be. The nearest point might be right next to you or far away.
Collins had to pilot the shuttle through a 360 degree flip while flying beneath the International Space Station. It allowed colleagues on the orbiting lab to photograph the craft's underside and check if the heatshield had been breached.