高端网站建设有哪些,全国做网站的公,虚拟机怎么做网页,门头沟网站建设前文链接#xff1a;QGraphicsView实现简易地图1『加载离线瓦片地图』 地图采用GCJ02 Web 墨卡托投影#xff0c;最小坐标#xff1a;(-180.00000000000000,-85.05112877980655)#xff0c;最大坐标#xff1a;(180.00000000000000,85.05112877980655)。瓦片地图单张图片像…前文链接QGraphicsView实现简易地图1『加载离线瓦片地图』 地图采用GCJ02 Web 墨卡托投影最小坐标(-180.00000000000000,-85.05112877980655)最大坐标(180.00000000000000,85.05112877980655)。瓦片地图单张图片像素大小为256*256经度均分256像素但纬度分布不均匀需要公式计算。 1、动态演示效果
2、静态展示图片
核心代码 1、数据定义GeoData.h
#pragma once
#include QMetaType/** 地理几何数据* 瓦片地图坐标投影GCJ02 Web 墨卡托投影*/#define PIXMAP_SIZE 256// 瓦片坐标
struct TileCoord
{TileCoord(double _x, double _y) : x(_x), y(_y) {}double x;double y;
};// 经纬度坐标
struct GeoCoord
{GeoCoord() default;GeoCoord(double _lon, double _lat) : lon(_lon), lat(_lat) {}double lon; // 经度double lat; // 纬度
};
Q_DECLARE_METATYPE(GeoCoord)2、MapUtility类
#pragma once
#include QPointF
#include DataStruct/GeoData.hclass MapUtility
{
public:// 场景坐标转经纬度static GeoCoord geoCoordFromScene(QPointF scenePos, int level);private:// 场景坐标转瓦片坐标瓦片坐标系static TileCoord tileCoordFromScene(QPointF scenePos, int level);// 场景坐标转所在瓦片像素点坐标static QPointF tilePixelCoordFromScene(QPointF scenePos, int level);
};#include MapUtility.h
#include TileUtility.hGeoCoord MapUtility::geoCoordFromScene(QPointF scenePos, int level)
{TileCoord tileCoord tileCoordFromScene(scenePos, level);QPointF tilePixelCoord tilePixelCoordFromScene(scenePos, level);return TileUtility::pixelToLonLat(tilePixelCoord.x(), tilePixelCoord.y(), tileCoord.x, tileCoord.y, level);
}TileCoord MapUtility::tileCoordFromScene(QPointF scenePos, int level)
{int tileX std::floor(scenePos.x() / PIXMAP_SIZE);int tileY std::floor(scenePos.y() / PIXMAP_SIZE);return TileCoord(tileX, tileY);
}QPointF MapUtility::tilePixelCoordFromScene(QPointF scenePos, int level)
{TileCoord tileCoord tileCoordFromScene(scenePos, level);double left tileCoord.x * PIXMAP_SIZE; // scenePos所在瓦片的左侧位于场景中的坐标double top tileCoord.y * PIXMAP_SIZE; // scenePos所在瓦片的上侧位于场景中的坐标return QPointF(scenePos.x() - left, scenePos.y() - top);
}3、TileUtility类
class TileUtility
{friend class MapUtility;private:/*** 将地图层级下瓦片的像素点转换到经纬度* 瓦片地图左上角为(0, 0)点* param pixelX 瓦片像素点X* param pixelY 瓦片像素点Y* param tileX 瓦片坐标X* param tileY 瓦片坐标Y* param level 瓦片层级* return 经纬度坐标*/static GeoCoord pixelToLonLat(double pixelX, double pixelY, int tileX, int tileY, int level);static double pixelXToLon(double pixelX, double tileX, int level);static double pixelXToLat(double pixelY, double tileY, int level);static double mathSinH(double value);/*** 获取地图层级下X/Y轴上的瓦片数量* param level 瓦片层级* return 瓦片数量*/static int mapSize(int level);
};GeoCoord TileUtility::pixelToLonLat(double pixelX, double pixelY, int tileX, int tileY, int level)
{double lon pixelXToLon(pixelX, tileX, level);double lat pixelXToLat(pixelY, tileY, level);return GeoCoord(lon, lat);
}double TileUtility::pixelXToLon(double pixelX, double tileX, int level)
{const double pixelXToTileAddition pixelX / PIXMAP_SIZE;const double lon (tileX pixelXToTileAddition) / mapSize(level) * 360 - 180;return lon;
}double TileUtility::pixelXToLat(double pixelY, double tileY, int level)
{const double pixelYToTileAddition pixelY / PIXMAP_SIZE;const double lat qAtan(mathSinH(M_PI * (1 - 2 * (tileY pixelYToTileAddition) / mapSize(level)))) * 180.0 / M_PI;return lat;
}double TileUtility::mathSinH(double value)
{return (qExp(value) - qExp(-value)) / 2;
}int TileUtility::mapSize(int level)
{return pow(2, level);
}4、场景鼠标移动事件
void MapScene::mouseMoveEvent(QGraphicsSceneMouseEvent *mouseEvent)
{m_coordPos MapUtility::geoCoordFromScene(mouseEvent-scenePos(), m_curLevel);emit geoCoordChanged(m_coordPos);
}
