feat: 新增月掩与日月食地理绘图并提升观测计算精度
- 新增月掩恒星和行星：支持搜索、掩甚点、全球掩带及固定地点轨迹计算 - 支持恒星星表坐标转换、有限盘面行星接触事件和月掩 SVG 输出 - 新增日月食及月掩全球投影图、时间标记和 GeoJSON 地理数据接口 - 扩展日食中心线、南北界及偏食足迹采样，支持极区投影 - 修正站心时角、月出月落、月球视半径、折射和恒星自行计算 - 优化内外行星事件搜索、边界选择、极端输入处理和计算稳定性
This commit is contained in:
@@ -0,0 +1,625 @@
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package svg
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import (
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"fmt"
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"html"
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"math"
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"sort"
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"strings"
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"time"
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eclipsecore "b612.me/astro/eclipse"
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"b612.me/astro/internal/svgmap"
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)
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type solarEclipseMapLayout struct {
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frame svgmap.Frame
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panelX float64
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panelY float64
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panelWidth float64
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panelHeight float64
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}
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type solarEclipseGlobalEventRow struct {
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kind string
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name string
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time time.Time
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point eclipsecore.SolarEclipsePathPoint
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hasPoint bool
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}
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func solarEclipseMapLayoutFor(options SolarEclipseMapSVGOptions, projection svgmap.Projection) solarEclipseMapLayout {
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width := float64(options.Width)
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height := float64(options.Height)
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margin := math.Max(26, math.Min(45, width*0.04))
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gap := math.Max(16, math.Min(24, width*0.025))
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panelWidth := math.Max(148, math.Min(238, width*0.22))
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availableWidth := width - 2*margin - gap - panelWidth
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bottomReserve := 92.0
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if projection != svgmap.ProjectionEquirectangular {
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bottomReserve = 118
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}
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availableHeight := math.Max(110, height-142-bottomReserve)
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mapWidth := math.Min(availableWidth, availableHeight*2)
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mapHeight := mapWidth / 2
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if projection != svgmap.ProjectionEquirectangular {
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mapWidth = math.Min(availableWidth, availableHeight)
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mapHeight = mapWidth
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}
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mapY := 142 + math.Max(0, (availableHeight-mapHeight)/2)
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groupWidth := mapWidth + gap + panelWidth
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mapX := math.Max(margin, (width-groupWidth)/2)
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return solarEclipseMapLayout{
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frame: svgmap.Frame{
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X: mapX, Y: mapY, Width: mapWidth, Height: mapHeight, Projection: projection,
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},
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panelX: mapX + mapWidth + gap,
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panelY: mapY,
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panelWidth: panelWidth,
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panelHeight: mapHeight,
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}
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}
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func writeSolarEclipseMapSectionTitle(
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builder *strings.Builder,
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layout solarEclipseMapLayout,
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options SolarEclipseMapSVGOptions,
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hasCentral bool,
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) {
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label := options.MapTitle
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if label == "" {
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if options.Language == "en" && hasCentral {
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label = "Global visibility and central path"
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} else if options.Language == "en" {
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label = "Global visibility"
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} else if hasCentral {
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label = "全球见食范围与中心食带"
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} else {
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label = "全球见食范围"
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}
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}
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fmt.Fprintf(builder, `<text x="%.3f" y="%.3f" fill="#161a1b" font-family="Georgia, 'Times New Roman', serif" font-size="14" font-weight="700">%s</text>`,
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layout.frame.X, layout.frame.Y-10, html.EscapeString(label))
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}
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func writeSolarEclipseGlobalEventsPanel(
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builder *strings.Builder,
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partial eclipsecore.SolarEclipsePartialFootprintsInfo,
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path eclipsecore.SolarEclipsePath,
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hasCentral bool,
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layout solarEclipseMapLayout,
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options SolarEclipseMapSVGOptions,
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) {
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rows := solarEclipseGlobalEventRows(partial, path, hasCentral, options.Language)
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title := options.EventsTitle
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if title == "" {
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if options.Language == "en" {
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title = "Global phases"
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} else {
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title = "全球阶段"
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}
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}
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fmt.Fprintf(builder, `<g class="solar-global-events">`)
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fmt.Fprintf(builder, `<line x1="%.3f" y1="%.3f" x2="%.3f" y2="%.3f" stroke="#d0d3d1" stroke-width="1"/>`,
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layout.panelX-10, layout.panelY, layout.panelX-10, layout.panelY+layout.panelHeight)
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fmt.Fprintf(builder, `<text x="%.3f" y="%.3f" fill="#161a1b" font-family="Georgia, 'Times New Roman', serif" font-size="14" font-weight="700">%s</text>`,
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layout.panelX, layout.panelY+13, html.EscapeString(title))
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rowTop := layout.panelY + 27
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rowHeight := math.Max(21, (layout.panelHeight-27)/float64(len(rows)))
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for index, row := range rows {
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y := rowTop + float64(index)*rowHeight
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if index > 0 {
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fmt.Fprintf(builder, `<line x1="%.3f" y1="%.3f" x2="%.3f" y2="%.3f" stroke="#e0e1df" stroke-width="0.8"/>`,
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layout.panelX, y-5, layout.panelX+layout.panelWidth, y-5)
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}
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fmt.Fprintf(builder, `<text x="%.3f" y="%.3f" fill="#1c2528" font-family="Arial, sans-serif" font-size="11" font-weight="700">%s</text>`,
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layout.panelX, y+10, html.EscapeString(row.name))
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fmt.Fprintf(builder, `<text x="%.3f" y="%.3f" fill="#1c2528" font-family="Arial, sans-serif" font-size="10" text-anchor="end">%s</text>`,
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layout.panelX+layout.panelWidth, y+10, html.EscapeString(row.time.In(options.Location).Format("15:04:05")))
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if row.hasPoint && rowHeight >= 45 {
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fmt.Fprintf(builder, `<text x="%.3f" y="%.3f" fill="#4c585a" font-family="Arial, sans-serif" font-size="10">%s</text>`,
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layout.panelX, y+27, html.EscapeString(solarEclipseFormatCoordinates(row.point.Longitude, row.point.Latitude)))
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}
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if row.hasPoint && rowHeight >= 52 {
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detail := solarEclipseGlobalEventDetail(row, partial.Eclipse, options.Language)
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fmt.Fprintf(builder, `<text x="%.3f" y="%.3f" fill="#697476" font-family="Arial, sans-serif" font-size="9">%s</text>`,
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layout.panelX, y+43, html.EscapeString(detail))
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}
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}
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builder.WriteString(`</g>`)
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}
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func solarEclipseGlobalEventRows(
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partial eclipsecore.SolarEclipsePartialFootprintsInfo,
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path eclipsecore.SolarEclipsePath,
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hasCentral bool,
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language string,
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) []solarEclipseGlobalEventRow {
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info := partial.Eclipse
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names := []string{"偏食始", "中心食始", "食甚", "中心食终", "偏食终"}
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if language == "en" {
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names = []string{"Partial begins", "Central begins", "Greatest", "Central ends", "Partial ends"}
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}
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rows := make([]solarEclipseGlobalEventRow, 0, 11)
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appendContact := func(name string, point eclipsecore.SolarEclipsePathPoint) {
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if point.Time.IsZero() {
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return
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}
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rows = append(rows, solarEclipseGlobalEventRow{
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kind: "shadow-contact", name: name, time: point.Time, point: point, hasPoint: true,
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})
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}
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appendContact("P1 "+names[0], partial.P1)
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appendContact("P2", partial.P2)
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appendContact("U1", partial.U1)
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appendContact("U2", partial.U2)
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if hasCentral && len(path.CenterLine) > 0 {
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rows = append(rows, solarEclipseGlobalEventRow{
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kind: "central-start", name: names[1], time: info.CentralBeginOnEarth,
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point: path.CenterLine[0], hasPoint: true,
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})
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}
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greatest := eclipsecore.SolarEclipsePathPoint{
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Time: info.GreatestEclipse, Longitude: info.GreatestLongitude,
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Latitude: info.GreatestLatitude, WidthKM: info.PathWidthKM,
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}
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if hasCentral {
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greatest = path.Greatest
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}
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rows = append(rows, solarEclipseGlobalEventRow{
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kind: "greatest", name: names[2], time: info.GreatestEclipse,
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point: greatest, hasPoint: true,
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})
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appendContact("U3", partial.U3)
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appendContact("U4", partial.U4)
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if hasCentral && len(path.CenterLine) > 0 {
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rows = append(rows, solarEclipseGlobalEventRow{
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kind: "central-end", name: names[3], time: info.CentralEndOnEarth,
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point: path.CenterLine[len(path.CenterLine)-1], hasPoint: true,
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})
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}
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appendContact("P3", partial.P3)
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appendContact("P4 "+names[4], partial.P4)
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if len(rows) == 0 || partial.P1.Time.IsZero() {
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rows = append(rows, solarEclipseGlobalEventRow{kind: "partial-start", name: names[0], time: info.PartialBeginOnEarth})
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}
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if partial.P4.Time.IsZero() {
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rows = append(rows, solarEclipseGlobalEventRow{kind: "partial-end", name: names[4], time: info.PartialEndOnEarth})
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}
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sort.SliceStable(rows, func(i, j int) bool { return rows[i].time.Before(rows[j].time) })
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return rows
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}
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func solarEclipseGlobalEventDetail(
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row solarEclipseGlobalEventRow,
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info eclipsecore.SolarEclipseInfo,
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language string,
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) string {
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if row.kind == "greatest" {
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if info.HasCentral {
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if language == "en" {
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return fmt.Sprintf("Path width %.1f km", info.PathWidthKM)
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}
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return fmt.Sprintf("食带宽 %.1f km", info.PathWidthKM)
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}
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if language == "en" {
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return fmt.Sprintf("Magnitude %.3f", info.Magnitude)
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}
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return fmt.Sprintf("食分 %.3f", info.Magnitude)
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}
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if language == "en" {
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return fmt.Sprintf("Sun altitude %+.1f°", row.point.SunAltitude)
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}
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return fmt.Sprintf("太阳高度 %+.1f°", row.point.SunAltitude)
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}
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func writeSolarEclipseTerminator(
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builder *strings.Builder,
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info eclipsecore.SolarEclipseInfo,
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frame svgmap.Frame,
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) {
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terminator := svgmap.SphericalCircle(solarEclipseSubsolarPoint(info.GreatestEclipse), 90, 360)
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if len(terminator) > 0 {
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terminator = append(terminator, terminator[0])
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}
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writeEclipseMapGeoLine(
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builder, frame, terminator, "solar-greatest-terminator", "#6f7778", 1.05, "4 3", "solar-map-clip",
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)
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}
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func writeSolarEclipsePenumbralOutlines(
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builder *strings.Builder,
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info eclipsecore.SolarEclipsePartialFootprintsInfo,
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frame svgmap.Frame,
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options SolarEclipseMapSVGOptions,
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) {
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if options.PenumbralOutlineStep <= 0 {
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return
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}
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selected := solarEclipseFootprintsAtStep(
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info.Footprints,
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options.PenumbralOutlineStep,
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options.Location,
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info.Eclipse.GreatestEclipse,
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)
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labelPositions := make([][2]float64, 0, len(selected))
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for _, footprint := range selected {
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writeSolarEclipseFootprintBoundary(
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builder, footprint, frame, "solar-penumbral-outline", "#b07a18", 0.75, "3 3",
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)
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if mapTimeDistance(footprint.Time, info.Eclipse.GreatestEclipse) <= info.Step/2 {
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continue
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}
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x, y, ok := solarEclipseFootprintLabelPosition(footprint, frame)
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if !ok || solarEclipseMapLabelOverlaps(x, y, labelPositions) {
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continue
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}
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labelPositions = append(labelPositions, [2]float64{x, y})
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labelTime := solarEclipseMapAlignedTime(footprint.Time, options.PenumbralOutlineStep, options.Location)
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fmt.Fprintf(builder, `<text class="solar-penumbral-time-label" x="%.3f" y="%.3f" fill="#8b5b08" stroke="#ffffff" stroke-width="2.4" paint-order="stroke" font-family="Arial, sans-serif" font-size="8" font-weight="700" text-anchor="middle">%s</text>`,
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x, y-4, html.EscapeString(labelTime.Format("15:04")))
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}
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}
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func writeSolarEclipseCentralShadowOutlines(
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builder *strings.Builder,
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footprints []eclipsecore.SolarEclipsePartialFootprint,
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frame svgmap.Frame,
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) {
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for _, footprint := range footprints {
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writeSolarEclipseFootprintBoundary(
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builder, footprint, frame, "solar-central-shadow-outline", "#7b5a42", 0.8, "",
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)
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}
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}
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func solarEclipseFootprintLabelPosition(
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footprint eclipsecore.SolarEclipsePartialFootprint,
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frame svgmap.Frame,
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) (float64, float64, bool) {
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bestX, bestY, bestScore := 0.0, 0.0, math.Inf(1)
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centerX := frame.X + frame.Width/2
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for _, boundary := range footprint.Boundaries {
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for _, point := range boundary {
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x, y, visible := frame.Project(point.Longitude, point.Latitude)
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if !visible || x < frame.X+24 || x > frame.X+frame.Width-24 ||
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y < frame.Y+14 || y > frame.Y+frame.Height-14 {
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continue
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}
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score := y + 0.05*math.Abs(x-centerX)
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if score < bestScore {
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bestX, bestY, bestScore = x, y, score
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}
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}
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}
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return bestX, bestY, !math.IsInf(bestScore, 1)
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}
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func solarEclipseMapLabelOverlaps(x, y float64, positions [][2]float64) bool {
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for _, position := range positions {
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if math.Abs(x-position[0]) < 52 && math.Abs(y-position[1]) < 17 {
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return true
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}
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}
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return false
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}
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func solarEclipseMapAlignedTime(value time.Time, step time.Duration, location *time.Location) time.Time {
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local := value.In(location)
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dayStart := time.Date(local.Year(), local.Month(), local.Day(), 0, 0, 0, 0, location)
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elapsed := local.Sub(dayStart)
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return dayStart.Add(((elapsed + step/2) / step) * step)
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}
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func writeSolarEclipseFootprintBoundary(
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builder *strings.Builder,
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footprint eclipsecore.SolarEclipsePartialFootprint,
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frame svgmap.Frame,
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className, color string,
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strokeWidth float64,
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dash string,
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) {
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for _, boundary := range footprint.Boundaries {
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points := make([]svgmap.GeoPoint, len(boundary))
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for index, point := range boundary {
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points[index] = svgmap.GeoPoint{Longitude: point.Longitude, Latitude: point.Latitude}
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}
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writeEclipseMapGeoLine(builder, frame, points, className, color, strokeWidth, dash, "solar-map-clip")
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}
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}
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func solarEclipseFootprintsAtStep(
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footprints []eclipsecore.SolarEclipsePartialFootprint,
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step time.Duration,
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location *time.Location,
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include time.Time,
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) []eclipsecore.SolarEclipsePartialFootprint {
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if len(footprints) == 0 || step <= 0 {
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return nil
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}
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targets := make([]time.Time, 0)
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for value := firstMapTimeLabelAfter(footprints[0].Time, step, location); !value.After(footprints[len(footprints)-1].Time); value = value.Add(step) {
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targets = append(targets, value)
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}
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if !include.IsZero() {
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targets = append(targets, include)
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}
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sort.Slice(targets, func(i, j int) bool { return targets[i].Before(targets[j]) })
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selected := make([]eclipsecore.SolarEclipsePartialFootprint, 0, len(targets))
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index := 0
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for _, target := range targets {
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for index+1 < len(footprints) &&
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mapTimeDistance(footprints[index+1].Time, target) < mapTimeDistance(footprints[index].Time, target) {
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index++
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}
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candidate := footprints[index]
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if len(selected) == 0 || !selected[len(selected)-1].Time.Equal(candidate.Time) {
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selected = append(selected, candidate)
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}
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}
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return selected
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}
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func mapTimeDistance(a, b time.Time) time.Duration {
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value := a.Sub(b)
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if value < 0 {
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return -value
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}
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return value
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}
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func writeSolarEclipseContactMarkers(
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builder *strings.Builder,
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info eclipsecore.SolarEclipsePartialFootprintsInfo,
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frame svgmap.Frame,
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) {
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type marker struct {
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name string
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point eclipsecore.SolarEclipsePathPoint
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color string
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labelDX float64
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labelDY float64
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textAnchor string
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}
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markers := []marker{
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{name: "P1", point: info.P1, color: "#a52d70", labelDX: -7, labelDY: 14, textAnchor: "end"},
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{name: "P2", point: info.P2, color: "#a52d70", labelDX: 7, labelDY: -7, textAnchor: "start"},
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{name: "P3", point: info.P3, color: "#a52d70", labelDX: -7, labelDY: -7, textAnchor: "end"},
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{name: "P4", point: info.P4, color: "#a52d70", labelDX: 7, labelDY: 14, textAnchor: "start"},
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{name: "U1", point: info.U1, color: "#a12c25", labelDX: -7, labelDY: -7, textAnchor: "end"},
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{name: "U2", point: info.U2, color: "#a12c25", labelDX: 7, labelDY: 14, textAnchor: "start"},
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{name: "U3", point: info.U3, color: "#a12c25", labelDX: -7, labelDY: 14, textAnchor: "end"},
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{name: "U4", point: info.U4, color: "#a12c25", labelDX: 7, labelDY: -7, textAnchor: "start"},
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}
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for _, marker := range markers {
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if marker.point.Time.IsZero() {
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continue
|
||||
}
|
||||
x, y, visible := frame.Project(marker.point.Longitude, marker.point.Latitude)
|
||||
if !visible {
|
||||
continue
|
||||
}
|
||||
labelX := x + marker.labelDX
|
||||
textAnchor := marker.textAnchor
|
||||
if labelX < frame.X+18 {
|
||||
labelX = x + 7
|
||||
textAnchor = "start"
|
||||
} else if labelX > frame.X+frame.Width-18 {
|
||||
labelX = x - 7
|
||||
textAnchor = "end"
|
||||
}
|
||||
fmt.Fprintf(builder, `<g class="solar-shadow-contact solar-contact-%s"><circle cx="%.3f" cy="%.3f" r="2.7" fill="%s" stroke="#ffffff" stroke-width="0.9"/><text x="%.3f" y="%.3f" fill="%s" stroke="#ffffff" stroke-width="2.4" paint-order="stroke" font-family="Arial, sans-serif" font-size="8" font-weight="700" text-anchor="%s">%s</text></g>`,
|
||||
strings.ToLower(marker.name), x, y, marker.color, labelX, y+marker.labelDY, marker.color,
|
||||
textAnchor, marker.name)
|
||||
}
|
||||
}
|
||||
|
||||
func writeSolarEclipseAxisMarkers(
|
||||
builder *strings.Builder,
|
||||
path eclipsecore.SolarEclipsePath,
|
||||
frame svgmap.Frame,
|
||||
options SolarEclipseMapSVGOptions,
|
||||
) {
|
||||
if len(path.CenterLine) < 2 {
|
||||
return
|
||||
}
|
||||
points := []eclipsecore.SolarEclipsePathPoint{path.CenterLine[0], path.CenterLine[len(path.CenterLine)-1]}
|
||||
for index, point := range points {
|
||||
x, y, visible := frame.Project(point.Longitude, point.Latitude)
|
||||
if !visible {
|
||||
continue
|
||||
}
|
||||
label := "中心线始"
|
||||
if index == 1 {
|
||||
label = "中心线终"
|
||||
}
|
||||
if options.Language == "en" {
|
||||
label = "Axis enters"
|
||||
if index == 1 {
|
||||
label = "Axis exits"
|
||||
}
|
||||
}
|
||||
fmt.Fprintf(builder, `<g class="solar-axis-contact" aria-label="%s"><title>%s</title><rect x="%.3f" y="%.3f" width="5" height="5" fill="#263f58" stroke="#ffffff" stroke-width="0.8"/></g>`,
|
||||
html.EscapeString(label), html.EscapeString(label), x-2.5, y-2.5)
|
||||
}
|
||||
}
|
||||
|
||||
func writeSolarEclipseSubsolarMarker(
|
||||
builder *strings.Builder,
|
||||
info eclipsecore.SolarEclipseInfo,
|
||||
frame svgmap.Frame,
|
||||
language string,
|
||||
) {
|
||||
point := solarEclipseSubsolarPoint(info.GreatestEclipse)
|
||||
x, y, visible := frame.Project(point.Longitude, point.Latitude)
|
||||
if !visible {
|
||||
return
|
||||
}
|
||||
label := "日下点"
|
||||
if language == "en" {
|
||||
label = "Subsolar"
|
||||
}
|
||||
fmt.Fprintf(builder, `<g class="solar-subsolar-marker"><circle cx="%.3f" cy="%.3f" r="4" fill="#f4c542" stroke="#714f00" stroke-width="1"/><path d="M %.3f %.3f h 8 M %.3f %.3f v 8" fill="none" stroke="#714f00" stroke-width="1"/><text x="%.3f" y="%.3f" fill="#714f00" stroke="#ffffff" stroke-width="2.5" paint-order="stroke" font-family="Arial, sans-serif" font-size="9" font-weight="700" text-anchor="middle">%s</text></g>`,
|
||||
x, y, x-4, y, x, y-4, x, y-9, html.EscapeString(label))
|
||||
}
|
||||
|
||||
func solarEclipseFormatCoordinates(longitude, latitude float64) string {
|
||||
lonSuffix := "E"
|
||||
if longitude < 0 {
|
||||
lonSuffix = "W"
|
||||
}
|
||||
latSuffix := "N"
|
||||
if latitude < 0 {
|
||||
latSuffix = "S"
|
||||
}
|
||||
return fmt.Sprintf("%.4f°%s, %.4f°%s", math.Abs(longitude), lonSuffix, math.Abs(latitude), latSuffix)
|
||||
}
|
||||
|
||||
func writeSolarEclipseTimeMarkers(
|
||||
builder *strings.Builder,
|
||||
path eclipsecore.SolarEclipsePath,
|
||||
frame svgmap.Frame,
|
||||
options SolarEclipseMapSVGOptions,
|
||||
) {
|
||||
if options.TimeLabelStep <= 0 || len(path.CenterLine) < 2 {
|
||||
return
|
||||
}
|
||||
excluded := []time.Time{
|
||||
path.Eclipse.CentralBeginOnEarth,
|
||||
path.Eclipse.CentralEndOnEarth,
|
||||
}
|
||||
markers := solarEclipseTimeMarkerPoints(path.CenterLine, options.TimeLabelStep, options.Location, excluded)
|
||||
projected := make([][2]float64, 0, len(markers))
|
||||
for _, marker := range markers {
|
||||
x, y, visible := frame.Project(marker.Longitude, marker.Latitude)
|
||||
if !visible || x < frame.X+22 || x > frame.X+frame.Width-22 || y < frame.Y+12 || y > frame.Y+frame.Height-12 {
|
||||
continue
|
||||
}
|
||||
tooClose := false
|
||||
for _, previous := range projected {
|
||||
if math.Hypot(x-previous[0], y-previous[1]) < 44 {
|
||||
tooClose = true
|
||||
break
|
||||
}
|
||||
}
|
||||
if tooClose {
|
||||
continue
|
||||
}
|
||||
projected = append(projected, [2]float64{x, y})
|
||||
labelY := y - 8
|
||||
if mapTimesNear(marker.Time, path.Eclipse.GreatestEclipse, solarEclipseGreatestTimeLabelWindow(options.TimeLabelStep)) {
|
||||
labelY = y + 15
|
||||
} else if labelY < frame.Y+10 {
|
||||
labelY = y + 15
|
||||
}
|
||||
fmt.Fprintf(builder, `<g class="solar-time-marker"><circle cx="%.3f" cy="%.3f" r="2.3" fill="#263f58" stroke="#ffffff" stroke-width="1"/><text x="%.3f" y="%.3f" fill="#263f58" stroke="#ffffff" stroke-width="3" paint-order="stroke" font-family="Arial, sans-serif" font-size="9" font-weight="700" text-anchor="middle">%s</text></g>`,
|
||||
x, y, x, labelY, html.EscapeString(marker.Time.In(options.Location).Format("15:04")))
|
||||
}
|
||||
}
|
||||
|
||||
func solarEclipseGreatestTimeLabelWindow(step time.Duration) time.Duration {
|
||||
window := step / 3
|
||||
if window < 10*time.Minute {
|
||||
return 10 * time.Minute
|
||||
}
|
||||
return window
|
||||
}
|
||||
|
||||
func solarEclipseTimeMarkerPoints(
|
||||
points []eclipsecore.SolarEclipsePathPoint,
|
||||
step time.Duration,
|
||||
location *time.Location,
|
||||
excluded []time.Time,
|
||||
) []eclipsecore.SolarEclipsePathPoint {
|
||||
if len(points) < 2 || step <= 0 {
|
||||
return nil
|
||||
}
|
||||
start := points[0].Time
|
||||
end := points[len(points)-1].Time
|
||||
current := firstMapTimeLabelAfter(start, step, location)
|
||||
window := step / 4
|
||||
if window > 5*time.Minute {
|
||||
window = 5 * time.Minute
|
||||
}
|
||||
if window < 30*time.Second {
|
||||
window = 30 * time.Second
|
||||
}
|
||||
result := make([]eclipsecore.SolarEclipsePathPoint, 0)
|
||||
segment := 1
|
||||
for current.Before(end) {
|
||||
for segment < len(points) && points[segment].Time.Before(current) {
|
||||
segment++
|
||||
}
|
||||
if segment >= len(points) {
|
||||
break
|
||||
}
|
||||
if !mapTimeNearAny(current, excluded, window) {
|
||||
a, b := points[segment-1], points[segment]
|
||||
span := b.Time.Sub(a.Time)
|
||||
if span > 0 {
|
||||
fraction := float64(current.Sub(a.Time)) / float64(span)
|
||||
result = append(result, interpolateSolarEclipsePathPoint(a, b, fraction, current))
|
||||
}
|
||||
}
|
||||
current = current.Add(step)
|
||||
}
|
||||
return result
|
||||
}
|
||||
|
||||
func interpolateSolarEclipsePathPoint(
|
||||
a, b eclipsecore.SolarEclipsePathPoint,
|
||||
fraction float64,
|
||||
value time.Time,
|
||||
) eclipsecore.SolarEclipsePathPoint {
|
||||
deltaLongitude := b.Longitude - a.Longitude
|
||||
if deltaLongitude > 180 {
|
||||
deltaLongitude -= 360
|
||||
} else if deltaLongitude < -180 {
|
||||
deltaLongitude += 360
|
||||
}
|
||||
longitude := a.Longitude + fraction*deltaLongitude
|
||||
if longitude > 180 {
|
||||
longitude -= 360
|
||||
} else if longitude < -180 {
|
||||
longitude += 360
|
||||
}
|
||||
return eclipsecore.SolarEclipsePathPoint{
|
||||
Time: value,
|
||||
Longitude: longitude,
|
||||
Latitude: a.Latitude + fraction*(b.Latitude-a.Latitude),
|
||||
SunAltitude: a.SunAltitude + fraction*(b.SunAltitude-a.SunAltitude),
|
||||
WidthKM: a.WidthKM + fraction*(b.WidthKM-a.WidthKM),
|
||||
}
|
||||
}
|
||||
|
||||
func firstMapTimeLabelAfter(value time.Time, step time.Duration, location *time.Location) time.Time {
|
||||
local := value.In(location)
|
||||
dayStart := time.Date(local.Year(), local.Month(), local.Day(), 0, 0, 0, 0, location)
|
||||
elapsed := local.Sub(dayStart)
|
||||
return dayStart.Add((elapsed/step + 1) * step)
|
||||
}
|
||||
|
||||
func mapTimeNearAny(value time.Time, excluded []time.Time, window time.Duration) bool {
|
||||
for _, candidate := range excluded {
|
||||
if candidate.IsZero() {
|
||||
continue
|
||||
}
|
||||
delta := value.Sub(candidate)
|
||||
if delta < 0 {
|
||||
delta = -delta
|
||||
}
|
||||
if delta <= window {
|
||||
return true
|
||||
}
|
||||
}
|
||||
return false
|
||||
}
|
||||
|
||||
func mapTimesNear(a, b time.Time, window time.Duration) bool {
|
||||
delta := a.Sub(b)
|
||||
if delta < 0 {
|
||||
delta = -delta
|
||||
}
|
||||
return delta <= window
|
||||
}
|
||||
Reference in New Issue
Block a user