Rvgeo NPM | npm.io

RVGeo 2.0.9 改动说明

demo: https://pzq123456.github.io/RVGeo/dist/index.html
docs: this site

2024.3.28 12:27:00 UTC + 08:00 该版本调整了项目结构，部分接口发生变化（降级或移除）。
降级：所有方法内指定 unit 单位的功能均不再支持，默认单位为米。在 math 模块下仍保留原来的单位换算方法，可以直接调用。主要目的是维护全局坐标系统一，原先的写法会默认带入 km、m 的混合问题。
重构：
Geometry 模块的所有代码均已重构，类中接口有部分改动，类继承关系完全改变。
需要注意的是，不再有 toArray 方法，现在可以直接（只读）获取符合 GeoJSON 标准的 coordinates 。具体改动可以参考源代码。
toXYArray 方法也都改名为 toXY 。这样做可以更好地统一独立geometry 与 multigeometry 之间的语意。
功能增强：
Topology 模块直接复制并修改 TopoJSON 代码库（将其由 js 转化为了 TypeScript），现在你可以将 GeoJSON 格式的数据转化为 TopoJSON，并调用一些诸如 merge、mesh 等方法来操纵它。（详细用法请参考 TopoJSON Client）
Geo 模块：参考 leaflet 为每一种投影及坐标系实现一个 object ，这样可以更好地管理多种坐标系。（当前仍然只有 wgs84 的投影与反投影）这也就意味着，原先的 plane2Wgs84 及其逆方法 Wgs842Plane 被移除。现在你需要指定某一投影实体 object，譬如 SphereMercator.project() 或 SphereMercator.unproject() 来达到同样的功能。

origonal RVGeo Welcom Page

Release Notes

2023-11-12 V2.0.7

new function for Class Grid : Grid.fillInvalidValue(bandIndex);
This function can replace the "invalid value" in given band with the mean value.
The so called values are now: -99999, 0. (may the 0 makes no sense and this function will uograde in the future)
新增 RGB 三通道遥感影像渲染，指定渲染通道对应的波段即可实现真彩色、标准假彩色等遥感影像的渲染。
Add RGB three-channel remote sensing image rendering, specify the band corresponding to the rendering channel to achieve the rendering of true color, standard false color and other remote sensing images.

新增影像直方图，正在测试中，仅供参考。

2023-11-12 V2.0.6

新增影像金字塔（Example14）图像傅里叶变换（Example15）
New image pyramid (Example14) image Fourier transform (Example15)

You can use RVGeo.Coverage.subdivide2QTree to get the image pyramid, and use RVGeo.Renderer.drawQTree2d to draw the image pyramid.

const subdivide2QTree = RVGeo.Coverage.subdivide2QTree;
const Grid = RVGeo.Coverage.Grid;
const drawQTree2d = RVGeo.Renderer.drawQTree2d;
const drawGrid2d = RVGeo.Renderer.drawGrid2d;
let mySimpleColorBand = RVGeo.Colors.simpleColorBandFactory(RVGeo.Colors.stretchType.linear);
axios.get('dem.csv').then((res)=>{
let data = parseData(res.data);
let grid = new Grid(myMBR1,[data]);
let subgrid = subdivide2QTree(grid,10); // 10 为金字塔层数
drawQTree2d(canvas,{x: 0, y: 0, w: 1024, h: 1024},subgrid,grid,mySimpleColorBand)
drawGrid2d(canvas, data, {x: 1024, y: 0, w: 1024, h: 1024}, grid.getBandStatistics(0), mySimpleColorBand);
});

You can use the following code segment to test 1D FFT and visualize the result.

const subdivide2QTree = RVGeo.Coverage.subdivide2QTree;
const Grid = RVGeo.Coverage.Grid;
const drawQTree2d = RVGeo.Renderer.drawQTree2d;
const drawGrid2d = RVGeo.Renderer.drawGrid2d;
let mySimpleColorBand = RVGeo.Colors.simpleColorBandFactory(RVGeo.Colors.stretchType.linear);
axios.get('dem.csv').then((res)=>{
let data = parseData(res.data);
let grid = new Grid(myMBR1,[data]);
let subgrid = subdivide2QTree(grid,10);
drawQTree2d(canvas,{x: 0, y: 0, w: 1024, h: 1024},subgrid,grid,mySimpleColorBand)
drawGrid2d(canvas, data, {x: 1024, y: 0, w: 1024, h: 1024}, grid.getBandStatistics(0), mySimpleColorBand);
});

You can use the following code segment to test 2D FFT and visualize the result.

  const subdivide2QTree = RVGeo.Coverage.subdivide2QTree;
  const Grid = RVGeo.Coverage.Grid;
  const drawQTree2d = RVGeo.Renderer.drawQTree2d;
  const drawGrid2d = RVGeo.Renderer.drawGrid2d;
  let mySimpleColorBand = RVGeo.Colors.simpleColorBandFactory(RVGeo.Colors.stretchType.linear);
  axios.get('dem.csv').then((res)=>{
  let data = parseData(res.data);
  let grid = new Grid(myMBR1,[data]);
  let subgrid = subdivide2QTree(grid,10);
  drawQTree2d(canvas,{x: 0, y: 0, w: 1024, h: 1024},subgrid,grid,mySimpleColorBand)
  drawGrid2d(canvas, data, {x: 1024, y: 0, w: 1024, h: 1024}, grid.getBandStatistics(0), mySimpleColorBand);
  });

2023-11-4 V2.0.5

新增等值线计算与渲染（基于 Marching Squares 方法）
Contour calculation and rendering (based on Marching Squares method)
You can use RVGeo.Renderer.drawCountour to draw contour lines, after you get the contour code from RVGeo.Coverage.Grid.getCoutourCode

  const drawCountour = RVGeo.Renderer.drawCountour;

  axios.get('dem.csv').then((res)=>{
    let data = parseData(res.data);
    let grid = new RVGeo.Coverage.Grid(myMBR1,[data]);
    let countour1 = grid.getCoutourCode(0,0.6);
    drawCountour(canvas, countour1, {x: 0, y: 0, w: 1024, h: 1024},"red");
  })