注意：圓角功能現(xiàn)已更新，使用矩形加圓角可直接生成操場輪廓。

下圖是一個中學的建筑、操場、綠地polygon數(shù)據(jù)，這些數(shù)據(jù)都是基于geobuilding繪制的，這里介紹下操場的繪制方法。

操場可以理解為2個半圓加一個長方形合并，我們使用參考線工具來繪制, 通過【左轉(zhuǎn)】、【右轉(zhuǎn)】調(diào)整地圖旋轉(zhuǎn)，確保操場水平線和水平刻度重合。拖動參考球(綠色)到合適的矩形位置。拖動到合適位置后，【鎖定參考線】。如下圖

下面開始繪制左邊的圓，步驟

拖動參考球410*410,正方形框，1點擊【繪制圖形】按鈕，2、然后選中剛繪制的矩形，輸入正40邊，點擊【框內(nèi)正】按鈕

選中這個圓形，點擊參考線工具【左右對稱復制】生成右側(cè)圓形

下面我們需要中間的長方形，還要確保長方形的四個頂點正好在圓的上下點上。拖動參考線十字距離左側(cè)205px；右側(cè)參考球到圓的上下點。拖動好了以后，點擊【創(chuàng)建圖形】得到矩形

按著shift鍵，同時選擇2個圓形和中間的矩形，點擊【面合并】按鈕

合并后隱藏參考線，如下圖，我們得到了漂亮的操場輪廓。

本教程地圖信息，打開geobuilding，在右側(cè)地圖信息粘貼可直達該位置。 {"zoom":17.06123136912676,"center":[116.14629597404104,39.72563348924925],"pitch":0}

繪制的跑道geojson數(shù)據(jù) {"id":"b34dcb8a432a1a216310cf80d2ccc14a","type":"Feature","properties":{"floor":1,"name":"","id":"b34dcb8a432a1a216310cf80d2ccc14a"},"geometry":{"coordinates":[[[116.14557110400716,39.72538878432343],[116.14557129756217,39.725388783946336],[116.1455771175672,39.725330004406715],[116.14559539120063,39.72527080266312],[116.14562548117965,39.72521452836315],[116.14566664659083,39.72516256717577],[116.1457178738039,39.72511619856854],[116.14577790143557,39.72507656430338],[116.14584525140629,39.72504464031917],[116.14591826533592,39.72502121270233],[116.14599514537991,39.725006858326196],[116.1460739984962,39.72500193064994],[116.146152883058,39.725006551011006],[116.1462298566683,39.72502060563855],[116.14630302397796,39.725043748456045],[116.14637058336751,39.725075409601374],[116.1464308713002,39.72511480946042],[116.14648240328614,39.72516097786615],[116.14652391043694,39.72521277798688],[116.14655437071013,39.72526893432095],[116.14657303407103,39.72532806410271],[116.1465792411826,39.72538682021288],[116.14657943473634,39.72538681983579],[116.1465820014106,39.72616612222848],[116.14658180785683,39.72616612260556],[116.14658200764103,39.72616801372865],[116.14657600031313,39.72622868443011],[116.14655772668124,39.726287885350644],[116.14652763670068,39.726344158774566],[116.14648647129104,39.72639611907155],[116.14643524407637,39.72644248681803],[116.14637521644465,39.72648212029736],[116.14630786647405,39.72651404361605],[116.1462348525443,39.72653747072627],[116.1461579725003,39.7265518247838],[116.14607911938566,39.72655675234927],[116.14600023482228,39.72655213209211],[116.14592326121198,39.7265380777761],[116.14585009390225,39.726514935460756],[116.1457825345127,39.72648327497646],[116.14572224658167,39.726443875899406],[116.14567071459578,39.72639770835198],[116.14562920744333,39.726345909121505],[116.14559874717179,39.72628975366521],[116.14558008380925,39.72623062470754],[116.14557367691185,39.72616997819466],[116.14557386423661,39.7261680863168],[116.14557367067982,39.72616808669389],[116.14557110400716,39.72538878432343]]],"type":"Polygon"}}

完