R 叶绿体：控制多边形填充

我上传了一个shapefile

然而，我相信有一个更优雅的解决方案。使用

id

作为建议的分组变量会导致多边形扭曲

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有人有其他想法吗？

多边形重叠，您可以设置

alpha

ggplot(plot.df, aes(x = long, y = lat)) +
  geom_polygon(aes(fill = factor(value), group = group), alpha = .4)+
  coord_fixed() +
  scale_fill_manual(values = c("red", "green", "blue", "orange"), breaks = c("1", "2", "3", "4")) +
  theme(legend.position = 'none')

ggplot(plot.df, aes(x=long, y=lat))+
    geom_polygon(aes(fill=factor(value), group=group))+
    geom_polygon(data=subset(plot.df, id==0), aes(fill=factor(value), group=group))+
    coord_fixed()+ 
    scale_fill_manual(values = c("red", "green", "blue", "orange"),
                breaks = c("1", "2", "3", "4"))

ggplot(plot.df, aes(x = long, y = lat)) +
  geom_polygon(aes(fill = factor(value), group = group), alpha = .4)+
  coord_fixed() +
  scale_fill_manual(values = c("red", "green", "blue", "orange"), breaks = c("1", "2", "3", "4")) +
  theme(legend.position = 'none')