Portolan Rhumb Chart

The portolan chart is the working drawing of the age of the compass: a navigational map inked by hand onto a whole sheepskin, its surface webbed with rhumb lines that spoke out from compass roses in red, black, and green. Coastlines were drawn close and scalloped, ports lettered perpendicular to the shore, and the great cities marked with gilded vignettes.

This system rebuilds that workshop hand for the screen. Type is set in Roman capitals and period serifs; color is the heraldic ink palette of the Catalan school — sea-darkened tan vellum, blood-red for the quarter winds, iron-gall brown-black for the principal coast, and muted gold leaf for the roses. Geometry radiates rather than gridding.

波特兰海图是罗盘时代的工作底稿——整张羊皮纸上，航海者用手笔将「恒向线」从一座座罗经花中辐射开来，红、黑、绿三色编码风向等级。海岸线绘得贴近而呈扇贝状，港口名称垂直于岸线书写，重要城市则以金箔小图徽标记。

这套系统把那只作坊之手搬到屏幕上：字体取罗马大写与时代衬线；配色沿用加泰罗尼亚学派的纹章墨水——被海水浸暗的棕褐羊皮、标记四分风与重要港口的纹章红、勾勒主海岸的铁胆墨棕黑，以及罗经花上柔哑的金箔。几何不作直角网格，而是从罗经花中向外放射。