Question

这是一个演示我的问题的演示：我在半径500000的地图上绘制一个圆圈，但在一个位置，圆圈看起来更大。我试图检查地图的缩放，它总是一样的。

＆＃13;

.container {
  height: 30px;
  width:100%;
}
#map {
  height: 400px;
}

＆＃13;

<script src="https://cdnjs.cloudflare.com/ajax/libs/leaflet/1.0.0-beta.2.rc.2/leaflet.js"></script>
<link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/leaflet/1.0.0-beta.2.rc.2/leaflet.css">

<div class="container">
<button id="name1">place1</button>
<button id="name2">place2</button>
</div>
<div id="map"></div>

＆＃13;

drop table artist;
drop table CDs;
drop table label;
drop table guests;
drop table genre;
drop table country;
drop table short_CD_info;
drop table short_guest_info;
create table artist(pseudo_of_artist varchar(50),name varchar(50), surname varchar(50), CDs varchar(50), date_of_birthday year, genre varchar(50),  country varchar(50));
create table CDs(title varchar(100), pseudo_of_artist varchar(50), label varchar(50), tracks int(50), pseudo_of_guests varchar(50), genre varchar(50), edition enum('Digipack','Plastic','Other'),year_of_cutting year,iTunes_bonus enum('Yes', 'No'));
create table label(name_of_label varchar(50), country varchar(50), owner varchar(50), year_of_founding year);
create table guests(pseudo_of_guests varchar(50), name varchar(50), surname varchar(50), date_of_birthday year, CDs varchar(100), country varchar(50));
create table genre(name_of_genre varchar(50), country varchar(50), example_of_artist varchar(50));
create table country(code varchar(10), full_name varchar(50));
create table short_CD_info(pseudo_of_artist varchar(50), title varchar(100));
create table short_guest_info(pseudo_of_guests varchar(50), title varchar(100));
ALTER TABLE artist 
ADD CONSTRAINT pk_artistID PRIMARY KEY(pseudo_of_artist);
alter table CDs
add constraint pk_CDsID primary key(title);
alter table label
add constraint pk_labelID primary key(name_of_label);
alter table guests
add constraint pk_guestsID primary key(pseudo_of_guests);
alter table genre
add constraint pk_genreID primary key(name_of_genre);
alter table country
add constraint pk_countryID primary key(code);
alter table short_CD_info
add constraint pk_scdiID primary key(pseudo_of_artist, title);
alter table short_guest_info
add constraint pk_sgiID primary key(pseudo_of_guests, title);
ALTER TABLE artist
ADD CONSTRAINT artits1_fk
FOREIGN KEY (CDs)
REFERENCES short_CD_info(title);
ALTER TABLE artist
ADD CONSTRAINT fk_artist2
FOREIGN KEY (genre)
REFERENCES genre(name_of_genre);
ALTER TABLE artist
ADD CONSTRAINT fk_artist3
FOREIGN KEY (country)
REFERENCES country(code);
ALTER TABLE CDs
ADD CONSTRAINT fk_CDs1
FOREIGN KEY (pseudo_of_artist)
REFERENCES short_CD_info(pseudo_of_artist);
ALTER TABLE CDs
ADD CONSTRAINT fk_CD2
FOREIGN KEY (label)
REFERENCES label(name_of_label);
ALTER TABLE CDs
ADD CONSTRAINT fk_CD3
FOREIGN KEY (pseudo_of_guests)
REFERENCES short_guest_info(pseudo_of_guests);
ALTER TABLE CDs
ADD CONSTRAINT fk_CD4
FOREIGN KEY (genre)
REFERENCES genre(name_of_genre);
ALTER TABLE label
ADD CONSTRAINT fk_label1
FOREIGN KEY (country)
REFERENCES country(code);
ALTER TABLE guests
ADD CONSTRAINT fk_guests1
FOREIGN KEY (CDs)
REFERENCES short_guest_info(title);
ALTER TABLE guests
ADD CONSTRAINT fk_guests2
FOREIGN KEY (country)
REFERENCES country(code);
ALTER TABLE genre
ADD CONSTRAINT fk_genre1
FOREIGN KEY (country)
REFERENCES country(code);
ALTER TABLE genre
ADD CONSTRAINT fk_genre2
FOREIGN KEY (example_of_artist)
REFERENCES artist(pseudo_of_artist);

＆＃13;

Answer 1

这是由于Mercator projection。引用维基百科：

墨卡托投影将对象的大小扭曲为纬度从赤道到极点的距离越来越大无限

place1的纬度比place2的纬度更靠近赤道，因此显得更小。

为什么圆圈尺寸会在地图上发生变化？

1 个答案: