778 lines
31 KiB
Go
778 lines
31 KiB
Go
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package svg
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import (
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"errors"
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"fmt"
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"html"
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"math"
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"strings"
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"time"
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"b612.me/astro/internal/svgasset"
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"b612.me/astro/moon"
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)
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const (
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localStarOccultationSVGDefaultWidth = 920
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localStarOccultationSVGDefaultHeight = 720
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localStarOccultationSVGMinimumWidth = 640
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localStarOccultationSVGMinimumHeight = 520
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localStarOccultationSVGDefaultStep = 2 * time.Minute
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)
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// ErrInvalidLocalStarOccultationSVGOptions 表示本地图表选项无效。
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// ErrInvalidLocalStarOccultationSVGOptions reports invalid local chart options.
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var ErrInvalidLocalStarOccultationSVGOptions = errors.New("invalid local stellar occultation SVG options")
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// ErrInvalidLocalStarOccultationInfo 表示固定地点事件数据格式错误。
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// ErrInvalidLocalStarOccultationInfo reports malformed fixed-site event data.
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var ErrInvalidLocalStarOccultationInfo = errors.New("invalid local stellar occultation info")
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// LocalStarOccultationSVGOptions 控制固定地点月球与恒星盘面图。
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// LocalStarOccultationSVGOptions controls a fixed-site Moon-star disk chart.
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type LocalStarOccultationSVGOptions struct {
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// Width 和 Height 是 SVG 画布尺寸；非正值使用默认值。
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// Width and Height are SVG canvas dimensions. Values <= 0 use defaults.
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Width int
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Height int
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// Step 是月心恒星轨迹请求采样步长；零值使用两分钟，负值无效，正值小于一秒时提升到一秒。长事件可能增大实际步长，以保持基础轨迹在有界采样预算内。
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// Step is the requested Moon-centered stellar-track sampling step. Zero uses two minutes; negative values are invalid. Positive values below one second are raised to one second, and long events may use a larger effective step to keep the base track within its bounded sample budget.
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Step time.Duration
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// 空文本字段使用本地化的自动标签。
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// Empty text fields use localized automatic labels.
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Title string
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SummaryText string
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GreatestText string
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OverviewTitle string
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PhasePanelsTitle string
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ContactsTitle string
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DirectionText string
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FooterNote string
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// Language 为 "en" 时使用英文，其他值使用中文。
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// Language uses English for "en" and Chinese for every other value.
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Language string
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// Location 控制显示的事件时刻；nil 使用 UTC+8。
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// Location controls displayed event times. Nil uses UTC+8.
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Location *time.Location
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}
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type localStarOccultationSVGLayout struct {
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width float64
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height float64
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margin float64
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overviewLeft float64
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overviewRight float64
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overviewTop float64
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overviewBottom float64
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panelX float64
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panelWidth float64
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stageTop float64
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stageBottom float64
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footerY float64
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}
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type localStarOccultationEventFrame struct {
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label string
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name string
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time time.Time
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frame moon.StarOccultationDiagramFrame
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}
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// FindLocalStarOccultationSVGs 搜索固定观测地点，并渲染请求时间窗口内的每次点光源恒星月掩。不会加载内嵌星表；空切片表示没有本地事件。
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// FindLocalStarOccultationSVGs searches one fixed observing site and renders every point-source stellar occultation in the requested time window. It does not load the embedded star catalog; an empty slice means no local event.
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func FindLocalStarOccultationSVGs(
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start, end time.Time,
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star moon.StarCoordinate,
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longitude, latitude, height float64,
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searchOptions moon.OccultationSearchOptions,
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options LocalStarOccultationSVGOptions,
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) ([]string, error) {
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if err := validateLocalStarOccultationSVGOptions(options); err != nil {
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return nil, err
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}
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events, err := moon.FindStarOccultations(start, end, star, longitude, latitude, height, searchOptions)
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if err != nil {
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return nil, err
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}
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diagrams := make([]string, 0, len(events))
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for _, event := range events {
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diagram, renderErr := LocalStarOccultationSVG(event, star, options)
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if renderErr != nil {
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return nil, renderErr
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}
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diagrams = append(diagrams, diagram)
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}
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return diagrams, nil
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}
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// LocalStarOccultationSVG 渲染已求解的固定地点恒星月掩的月心轨迹及掩始、掩甚、掩终阶段面板；不会运行事件搜索或加载星表。
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// LocalStarOccultationSVG renders an already solved fixed-site stellar occultation as a Moon-centered track with immersion, greatest, and emersion stage panels. It does not run the event search or load the star catalog.
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func LocalStarOccultationSVG(
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info moon.StarOccultationInfo,
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star moon.StarCoordinate,
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options LocalStarOccultationSVGOptions,
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) (string, error) {
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if err := validateLocalStarOccultationInfo(info, star); err != nil {
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return "", err
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}
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if err := validateLocalStarOccultationSVGOptions(options); err != nil {
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return "", err
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}
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options = normalizeLocalStarOccultationSVGOptions(options)
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diagram := moon.StarOccultationDiagram(info, star, moon.StarOccultationDiagramOptions{
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StepDays: options.Step.Hours() / 24,
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})
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if len(diagram.Frames) == 0 {
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return "", fmt.Errorf("%w: diagram geometry is unavailable", ErrInvalidLocalStarOccultationInfo)
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}
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return renderLocalStarOccultationSVG(info, diagram, options), nil
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}
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func validateLocalStarOccultationSVGOptions(options LocalStarOccultationSVGOptions) error {
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if options.Width > 0 && options.Width < localStarOccultationSVGMinimumWidth {
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return fmt.Errorf("%w: width must be zero or at least %d", ErrInvalidLocalStarOccultationSVGOptions, localStarOccultationSVGMinimumWidth)
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}
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if options.Height > 0 && options.Height < localStarOccultationSVGMinimumHeight {
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return fmt.Errorf("%w: height must be zero or at least %d", ErrInvalidLocalStarOccultationSVGOptions, localStarOccultationSVGMinimumHeight)
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}
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if options.Step < 0 {
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return fmt.Errorf("%w: step cannot be negative", ErrInvalidLocalStarOccultationSVGOptions)
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}
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return nil
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}
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func validateLocalStarOccultationInfo(info moon.StarOccultationInfo, star moon.StarCoordinate) error {
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if err := star.Validate(); err != nil {
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return fmt.Errorf("%w: %v", ErrInvalidLocalStarOccultationInfo, err)
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}
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if info.TargetID != "" && star.ID != "" && info.TargetID != star.ID {
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return fmt.Errorf("%w: event target %q does not match star %q", ErrInvalidLocalStarOccultationInfo, info.TargetID, star.ID)
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}
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if err := info.Observer.Validate(); err != nil {
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return fmt.Errorf("%w: %v", ErrInvalidLocalStarOccultationInfo, err)
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}
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if !info.ContactsComplete || info.Immersion.IsZero() || info.Greatest.IsZero() || info.Emersion.IsZero() {
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return fmt.Errorf("%w: complete immersion, greatest, and emersion times are required", ErrInvalidLocalStarOccultationInfo)
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}
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if info.Greatest.Before(info.Immersion) || info.Emersion.Before(info.Greatest) {
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return fmt.Errorf("%w: event times must be ordered", ErrInvalidLocalStarOccultationInfo)
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}
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if info.Type != moon.OccultationTotal && info.Type != moon.OccultationGrazing {
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return fmt.Errorf("%w: unsupported point-source geometry %q", ErrInvalidLocalStarOccultationInfo, info.Type)
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}
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if !starOccultationFinite(info.MinimumSeparationArcsec) || info.MinimumSeparationArcsec < 0 ||
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!starOccultationFinite(info.MoonSemidiameterArcsec) || info.MoonSemidiameterArcsec <= 0 ||
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!starOccultationFinite(info.PositionAngleDeg) ||
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!starOccultationFinite(info.MoonAltitudeAtGreatest) ||
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!starOccultationFinite(info.MoonAzimuthAtGreatest) {
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return fmt.Errorf("%w: event geometry must be finite", ErrInvalidLocalStarOccultationInfo)
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}
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return nil
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}
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func normalizeLocalStarOccultationSVGOptions(options LocalStarOccultationSVGOptions) LocalStarOccultationSVGOptions {
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if options.Width <= 0 {
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options.Width = localStarOccultationSVGDefaultWidth
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}
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if options.Height <= 0 {
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options.Height = localStarOccultationSVGDefaultHeight
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}
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if options.Step <= 0 {
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options.Step = localStarOccultationSVGDefaultStep
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}
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if options.Location == nil {
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options.Location = time.FixedZone("UTC+8", starOccultationSVGDefaultZone)
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}
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if strings.EqualFold(options.Language, starOccultationSVGLanguageEnglish) {
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options.Language = starOccultationSVGLanguageEnglish
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} else {
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options.Language = starOccultationSVGLanguageChinese
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}
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return options
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}
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func renderLocalStarOccultationSVG(
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info moon.StarOccultationInfo,
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diagram moon.StarOccultationDiagramResult,
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options LocalStarOccultationSVGOptions,
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) string {
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title := localStarOccultationSVGTitle(info, options)
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headerLines := localStarOccultationSVGHeaderLines(info, options)
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headerBottom := 72.0 + float64(len(headerLines))*19
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layout := localStarOccultationSVGLayoutFor(options, headerBottom)
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events := localStarOccultationSVGEventFrames(info, diagram.Frames, options.Language)
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var b strings.Builder
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fmt.Fprintf(&b, `<svg xmlns="http://www.w3.org/2000/svg" width="%d" height="%d" viewBox="0 0 %d %d" role="img" aria-label="%s">`,
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options.Width, options.Height, options.Width, options.Height, html.EscapeString(title))
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b.WriteString(`<defs>`)
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b.WriteString(svgasset.MoonFaceSymbol())
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b.WriteString(`<marker id="local-occultation-arrow" viewBox="0 0 10 10" refX="8" refY="5" markerWidth="5" markerHeight="5" orient="auto-start-reverse"><path d="M 0 0 L 10 5 L 0 10 z" fill="#9b3f36"/></marker>`)
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b.WriteString(`</defs>`)
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b.WriteString(`<rect width="100%" height="100%" fill="#efefed"/>`)
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fmt.Fprintf(&b, `<rect x="22" y="18" width="%.3f" height="%.3f" fill="#ffffff" stroke="#c9c9c6" stroke-width="1.2"/>`, layout.width-44, layout.height-36)
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fmt.Fprintf(&b, `<text x="%.3f" y="44" fill="#111111" font-family="Georgia, 'Times New Roman', serif" font-size="%d" font-weight="700" text-anchor="middle">%s</text>`,
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layout.width/2, starOccultationTitleFontSize(title, layout.width), html.EscapeString(title))
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fmt.Fprintf(&b, `<line x1="%.3f" y1="57" x2="%.3f" y2="57" stroke="#555" stroke-width="1"/>`, layout.width/2-78, layout.width/2+78)
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for index, line := range headerLines {
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fontSize, fill := 13, "#3b4143"
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if index == 0 {
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fontSize, fill = 14, "#222222"
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}
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fmt.Fprintf(&b, `<text x="%.3f" y="%.3f" fill="%s" font-family="Georgia, 'Times New Roman', serif" font-size="%d" text-anchor="middle">%s</text>`,
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layout.width/2, 82+float64(index)*19, fill, fontSize, html.EscapeString(line))
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}
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writeLocalStarOccultationOverview(&b, diagram, events, layout, options)
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writeLocalStarOccultationContacts(&b, events, layout, options)
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writeLocalStarOccultationStages(&b, events, layout, options)
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writeLocalStarOccultationFooter(&b, layout, options)
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b.WriteString(`</svg>`)
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return b.String()
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}
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func localStarOccultationSVGLayoutFor(options LocalStarOccultationSVGOptions, headerBottom float64) localStarOccultationSVGLayout {
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width := float64(options.Width)
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height := float64(options.Height)
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margin := math.Max(30, math.Min(44, width*0.05))
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gap := math.Max(18, math.Min(24, width*0.025))
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panelWidth := math.Max(188, math.Min(236, width*0.25))
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overviewLeft := margin
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overviewRight := width - margin - panelWidth - gap
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footerSpace := 64.0
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stageHeight := math.Max(132, math.Min(170, height*0.23))
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stageBottom := height - footerSpace
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stageTop := stageBottom - stageHeight
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overviewTop := headerBottom + 26
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overviewBottom := stageTop - 20
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return localStarOccultationSVGLayout{
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width: width,
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height: height,
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margin: margin,
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overviewLeft: overviewLeft,
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overviewRight: overviewRight,
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overviewTop: overviewTop,
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overviewBottom: overviewBottom,
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panelX: overviewRight + gap,
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panelWidth: panelWidth,
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stageTop: stageTop,
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stageBottom: stageBottom,
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footerY: height - 43,
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}
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}
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func writeLocalStarOccultationOverview(
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b *strings.Builder,
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diagram moon.StarOccultationDiagramResult,
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events []localStarOccultationEventFrame,
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layout localStarOccultationSVGLayout,
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options LocalStarOccultationSVGOptions,
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) {
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fmt.Fprintf(b, `<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.overviewLeft, layout.overviewTop-10, html.EscapeString(localStarOccultationSVGOverviewTitle(options)))
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cx := (layout.overviewLeft + layout.overviewRight) / 2
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cy := (layout.overviewTop+layout.overviewBottom)/2 + 4
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extent := localStarOccultationSVGExtent(diagram.Frames)
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availableWidth := layout.overviewRight - layout.overviewLeft - 74
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availableHeight := layout.overviewBottom - layout.overviewTop - 50
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scale := math.Min(availableWidth/(2*extent), availableHeight/(2*extent))
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if !starOccultationFinite(scale) || scale <= 0 {
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scale = 1
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}
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mapX := func(value float64) float64 { return cx - value*scale }
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mapY := func(value float64) float64 { return cy - value*scale }
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moonRadius := localStarOccultationSVGMaximumMoonRadius(diagram.Frames) * scale
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writeLocalStarOccultationAxes(b, cx, cy, moonRadius, options.Language)
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writeLocalStarOccultationMoon(b, cx, cy, moonRadius, "overview-moon")
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writeLocalStarOccultationLunarPath(b, diagram.Frames, mapX, mapY, extent, options.Language)
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writeLocalStarOccultationTrack(b, diagram.Frames, mapX, mapY)
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for _, event := range events {
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x := mapX(event.frame.StarXArcsec)
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y := mapY(event.frame.StarYArcsec)
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writeLocalStarOccultationStar(b, x, y, event.frame.BehindMoon, "overview-star", event.label)
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writeLocalStarOccultationOverviewLabel(b, event, x, y, cx, cy, options.Language)
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}
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}
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func localStarOccultationSVGExtent(frames []moon.StarOccultationDiagramFrame) float64 {
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extent := 1.0
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for _, frame := range frames {
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extent = math.Max(extent, frame.MoonRadiusArcsec)
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extent = math.Max(extent, math.Abs(frame.StarXArcsec))
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extent = math.Max(extent, math.Abs(frame.StarYArcsec))
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}
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return extent * 1.28
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}
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func localStarOccultationSVGMaximumMoonRadius(frames []moon.StarOccultationDiagramFrame) float64 {
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|
|
radius := 1.0
|
||
|
|
for _, frame := range frames {
|
||
|
|
radius = math.Max(radius, frame.MoonRadiusArcsec)
|
||
|
|
}
|
||
|
|
return radius
|
||
|
|
}
|
||
|
|
|
||
|
|
func writeLocalStarOccultationTrack(
|
||
|
|
b *strings.Builder,
|
||
|
|
frames []moon.StarOccultationDiagramFrame,
|
||
|
|
mapX, mapY func(float64) float64,
|
||
|
|
) {
|
||
|
|
if len(frames) < 2 {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
var path strings.Builder
|
||
|
|
for index, frame := range frames {
|
||
|
|
command := "L"
|
||
|
|
if index == 0 {
|
||
|
|
command = "M"
|
||
|
|
}
|
||
|
|
fmt.Fprintf(&path, "%s %.3f %.3f ", command, mapX(frame.StarXArcsec), mapY(frame.StarYArcsec))
|
||
|
|
}
|
||
|
|
fmt.Fprintf(b, `<path class="local-star-track" d="%s" fill="none" stroke="#9b3f36" stroke-width="1.7" stroke-dasharray="5 4" opacity="0.82" marker-end="url(#local-occultation-arrow)"/>`, strings.TrimSpace(path.String()))
|
||
|
|
}
|
||
|
|
|
||
|
|
func writeLocalStarOccultationLunarPath(
|
||
|
|
b *strings.Builder,
|
||
|
|
frames []moon.StarOccultationDiagramFrame,
|
||
|
|
mapX, mapY func(float64) float64,
|
||
|
|
extent float64,
|
||
|
|
language string,
|
||
|
|
) {
|
||
|
|
unitX, unitY, ok := localStarOccultationSVGLunarPathDirection(frames)
|
||
|
|
if !ok {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
lineExtent := extent * 0.92
|
||
|
|
startX := mapX(-unitX * lineExtent)
|
||
|
|
startY := mapY(-unitY * lineExtent)
|
||
|
|
endX := mapX(unitX * lineExtent)
|
||
|
|
endY := mapY(unitY * lineExtent)
|
||
|
|
if !starOccultationFinite(startX) || !starOccultationFinite(startY) ||
|
||
|
|
!starOccultationFinite(endX) || !starOccultationFinite(endY) {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
fmt.Fprintf(b, `<line class="lunar-path-line" x1="%.3f" y1="%.3f" x2="%.3f" y2="%.3f" stroke="#506975" stroke-width="1.1" stroke-dasharray="7 4" opacity="0.86"/>`,
|
||
|
|
startX, startY, endX, endY)
|
||
|
|
labelX, labelY, anchor := startX, startY, "end"
|
||
|
|
if endX < startX {
|
||
|
|
labelX, labelY = endX, endY
|
||
|
|
}
|
||
|
|
fmt.Fprintf(b, `<text class="lunar-path-label" x="%.3f" y="%.3f" fill="#405966" stroke="#ffffff" stroke-width="3" paint-order="stroke" font-family="Georgia, 'Times New Roman', serif" font-size="12" text-anchor="%s">%s</text>`,
|
||
|
|
labelX-6, labelY-6, anchor, html.EscapeString(localStarOccultationSVGLunarPathLabel(language)))
|
||
|
|
}
|
||
|
|
|
||
|
|
// 恒星轨迹相对固定月心测量，因此其切线与月球站心视运动反向。参考线没有箭头，因此归一化轨迹切线就是图表使用的月掩路径轴。
|
||
|
|
// The star track is measured relative to a fixed lunar center, so its tangent is antiparallel to the Moon's topocentric apparent motion. A reference line has no arrow, therefore the normalized track tangent is the same lunar-path axis used by the chart.
|
||
|
|
func localStarOccultationSVGLunarPathDirection(frames []moon.StarOccultationDiagramFrame) (float64, float64, bool) {
|
||
|
|
if len(frames) < 2 {
|
||
|
|
return 0, 0, false
|
||
|
|
}
|
||
|
|
greatest := -1
|
||
|
|
for index, frame := range frames {
|
||
|
|
if localStarOccultationSVGFrameHasLabel(frame, "Greatest") {
|
||
|
|
greatest = index
|
||
|
|
break
|
||
|
|
}
|
||
|
|
}
|
||
|
|
left, right := 0, len(frames)-1
|
||
|
|
if greatest > 0 && greatest+1 < len(frames) {
|
||
|
|
left, right = greatest-1, greatest+1
|
||
|
|
} else if greatest == 0 {
|
||
|
|
left, right = 0, 1
|
||
|
|
} else if greatest == len(frames)-1 {
|
||
|
|
left, right = len(frames)-2, len(frames)-1
|
||
|
|
}
|
||
|
|
dx := frames[right].StarXArcsec - frames[left].StarXArcsec
|
||
|
|
dy := frames[right].StarYArcsec - frames[left].StarYArcsec
|
||
|
|
length := math.Hypot(dx, dy)
|
||
|
|
if !starOccultationFinite(length) || length == 0 {
|
||
|
|
return 0, 0, false
|
||
|
|
}
|
||
|
|
return dx / length, dy / length, true
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGLunarPathLabel(language string) string {
|
||
|
|
if language == starOccultationSVGLanguageEnglish {
|
||
|
|
return "Lunar path"
|
||
|
|
}
|
||
|
|
return "白道"
|
||
|
|
}
|
||
|
|
|
||
|
|
func writeLocalStarOccultationMoon(b *strings.Builder, cx, cy, radius float64, class string) {
|
||
|
|
fmt.Fprintf(b, `<g class="%s">`, html.EscapeString(class))
|
||
|
|
fmt.Fprintf(b, `<use href="#le-moon" x="%.3f" y="%.3f" width="%.3f" height="%.3f"/>`,
|
||
|
|
cx-radius, cy-radius, radius*2, radius*2)
|
||
|
|
fmt.Fprintf(b, `<circle cx="%.3f" cy="%.3f" r="%.3f" fill="none" stroke="#4f5d60" stroke-width="1.1" opacity="0.9"/>`, cx, cy, radius)
|
||
|
|
b.WriteString(`</g>`)
|
||
|
|
}
|
||
|
|
|
||
|
|
func writeLocalStarOccultationAxes(b *strings.Builder, cx, cy, radius float64, language string) {
|
||
|
|
north, east, west, south := "北", "东", "西", "南"
|
||
|
|
if language == starOccultationSVGLanguageEnglish {
|
||
|
|
north, east, west, south = "N", "E", "W", "S"
|
||
|
|
}
|
||
|
|
labels := []struct {
|
||
|
|
x, y float64
|
||
|
|
anchor string
|
||
|
|
text string
|
||
|
|
}{
|
||
|
|
{cx, cy - radius - 15, "middle", north},
|
||
|
|
{cx - radius - 18, cy + 4, "middle", east},
|
||
|
|
{cx + radius + 18, cy + 4, "middle", west},
|
||
|
|
{cx, cy + radius + 24, "middle", south},
|
||
|
|
}
|
||
|
|
for _, label := range labels {
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#293235" font-family="Georgia, 'Times New Roman', serif" font-size="12" font-weight="700" text-anchor="%s">%s</text>`,
|
||
|
|
label.x, label.y, label.anchor, html.EscapeString(label.text))
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func writeLocalStarOccultationStar(b *strings.Builder, x, y float64, hidden bool, class, label string) {
|
||
|
|
fill, stroke, dash := "#fff7d6", "#9b3028", ""
|
||
|
|
if hidden {
|
||
|
|
fill, stroke, dash = "none", "#7d3430", ` stroke-dasharray="2 2"`
|
||
|
|
}
|
||
|
|
fmt.Fprintf(b, `<g class="%s" data-label="%s">`, html.EscapeString(class), html.EscapeString(label))
|
||
|
|
fmt.Fprintf(b, `<circle cx="%.3f" cy="%.3f" r="4.2" fill="%s" stroke="%s" stroke-width="1.4"%s/>`, x, y, fill, stroke, dash)
|
||
|
|
fmt.Fprintf(b, `<line x1="%.3f" y1="%.3f" x2="%.3f" y2="%.3f" stroke="%s" stroke-width="1"/>`, x-6, y, x+6, y, stroke)
|
||
|
|
fmt.Fprintf(b, `<line x1="%.3f" y1="%.3f" x2="%.3f" y2="%.3f" stroke="%s" stroke-width="1"/>`, x, y-6, x, y+6, stroke)
|
||
|
|
b.WriteString(`</g>`)
|
||
|
|
}
|
||
|
|
|
||
|
|
func writeLocalStarOccultationOverviewLabel(
|
||
|
|
b *strings.Builder,
|
||
|
|
event localStarOccultationEventFrame,
|
||
|
|
x, y, cx, cy float64,
|
||
|
|
language string,
|
||
|
|
) {
|
||
|
|
dx, dy, anchor := 8.0, -9.0, "start"
|
||
|
|
if x > cx {
|
||
|
|
dx, anchor = -8, "end"
|
||
|
|
}
|
||
|
|
if y < cy-20 {
|
||
|
|
dy = 15
|
||
|
|
}
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#792d28" stroke="#ffffff" stroke-width="3" paint-order="stroke" font-family="Arial, sans-serif" font-size="11" font-weight="700" text-anchor="%s">%s</text>`,
|
||
|
|
x+dx, y+dy, anchor, html.EscapeString(localStarOccultationSVGEventName(event.label, language)))
|
||
|
|
}
|
||
|
|
|
||
|
|
func writeLocalStarOccultationContacts(
|
||
|
|
b *strings.Builder,
|
||
|
|
events []localStarOccultationEventFrame,
|
||
|
|
layout localStarOccultationSVGLayout,
|
||
|
|
options LocalStarOccultationSVGOptions,
|
||
|
|
) {
|
||
|
|
fmt.Fprintf(b, `<line x1="%.3f" y1="%.3f" x2="%.3f" y2="%.3f" stroke="#d0d3d1" stroke-width="1"/>`,
|
||
|
|
layout.panelX-12, layout.overviewTop-12, layout.panelX-12, layout.overviewBottom)
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#161a1b" font-family="Georgia, 'Times New Roman', serif" font-size="14" font-weight="700">%s</text>`,
|
||
|
|
layout.panelX, layout.overviewTop-10, html.EscapeString(localStarOccultationSVGContactsTitle(options)))
|
||
|
|
available := layout.overviewBottom - layout.overviewTop - 10
|
||
|
|
rowHeight := math.Min(86, available/math.Max(1, float64(len(events))))
|
||
|
|
for index, event := range events {
|
||
|
|
y := layout.overviewTop + 17 + float64(index)*rowHeight
|
||
|
|
if index > 0 {
|
||
|
|
fmt.Fprintf(b, `<line x1="%.3f" y1="%.3f" x2="%.3f" y2="%.3f" stroke="#e0e1df" stroke-width="0.8"/>`,
|
||
|
|
layout.panelX, y-13, layout.panelX+layout.panelWidth, y-13)
|
||
|
|
}
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#1c2528" font-family="Arial, sans-serif" font-size="12" font-weight="700">%s</text>`,
|
||
|
|
layout.panelX, y, html.EscapeString(event.name))
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#1c2528" font-family="Arial, sans-serif" font-size="11" text-anchor="end">%s</text>`,
|
||
|
|
layout.panelX+layout.panelWidth, y, html.EscapeString(event.time.In(options.Location).Format("15:04:05.0")))
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#536063" font-family="Arial, sans-serif" font-size="10">PA %.1f° | %s %.1f°</text>`,
|
||
|
|
layout.panelX, y+18, event.frame.PositionAngleDeg, localStarOccultationSVGAltitudeLabel(options.Language), event.frame.MoonAltitudeDeg)
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#6b7577" font-family="Arial, sans-serif" font-size="10">%s %.1f° | %s</text>`,
|
||
|
|
layout.panelX, y+34, localStarOccultationSVGAzimuthLabel(options.Language), event.frame.MoonAzimuthDeg,
|
||
|
|
html.EscapeString(localStarOccultationSVGVisibilityText(event.frame.MoonAltitudeDeg >= 0, options.Language)))
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func writeLocalStarOccultationStages(
|
||
|
|
b *strings.Builder,
|
||
|
|
events []localStarOccultationEventFrame,
|
||
|
|
layout localStarOccultationSVGLayout,
|
||
|
|
options LocalStarOccultationSVGOptions,
|
||
|
|
) {
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#161a1b" font-family="Georgia, 'Times New Roman', serif" font-size="14" font-weight="700">%s</text>`,
|
||
|
|
layout.margin, layout.stageTop+13, html.EscapeString(localStarOccultationSVGPhasePanelsTitle(options)))
|
||
|
|
if len(events) == 0 {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
usableWidth := layout.width - 2*layout.margin
|
||
|
|
columnWidth := usableWidth / float64(len(events))
|
||
|
|
maxMoonRadius := localStarOccultationSVGMaximumMoonRadiusFromEvents(events)
|
||
|
|
radius := math.Min(46, math.Max(31, (layout.stageBottom-layout.stageTop-53)/2))
|
||
|
|
scale := radius / maxMoonRadius
|
||
|
|
cy := layout.stageTop + 34 + radius
|
||
|
|
for index, event := range events {
|
||
|
|
cx := layout.margin + columnWidth*(float64(index)+0.5)
|
||
|
|
writeLocalStarOccultationMoon(b, cx, cy, event.frame.MoonRadiusArcsec*scale, "stage-moon")
|
||
|
|
x := cx - event.frame.StarXArcsec*scale
|
||
|
|
y := cy - event.frame.StarYArcsec*scale
|
||
|
|
writeLocalStarOccultationStar(b, x, y, event.frame.BehindMoon, "stage-star", event.label)
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#1c2528" font-family="Arial, sans-serif" font-size="11" font-weight="700" text-anchor="middle">%s</text>`,
|
||
|
|
cx, cy+radius+19, html.EscapeString(event.name))
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#667174" font-family="Arial, sans-serif" font-size="10" text-anchor="middle">%s</text>`,
|
||
|
|
cx, cy+radius+34, html.EscapeString(event.time.In(options.Location).Format("15:04:05.0")))
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGMaximumMoonRadiusFromEvents(events []localStarOccultationEventFrame) float64 {
|
||
|
|
radius := 1.0
|
||
|
|
for _, event := range events {
|
||
|
|
radius = math.Max(radius, event.frame.MoonRadiusArcsec)
|
||
|
|
}
|
||
|
|
return radius
|
||
|
|
}
|
||
|
|
|
||
|
|
func writeLocalStarOccultationFooter(
|
||
|
|
b *strings.Builder,
|
||
|
|
layout localStarOccultationSVGLayout,
|
||
|
|
options LocalStarOccultationSVGOptions,
|
||
|
|
) {
|
||
|
|
directionLines := starOccultationWrapText(localStarOccultationSVGDirectionText(options), layout.width-80, 10)
|
||
|
|
for index, line := range directionLines {
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#4f595b" font-family="Georgia, 'Times New Roman', serif" font-size="10">%s</text>`,
|
||
|
|
layout.margin, layout.footerY+float64(index)*14-8, html.EscapeString(line))
|
||
|
|
}
|
||
|
|
footerLines := starOccultationWrapText(localStarOccultationSVGFooterNote(options), layout.width-80, 9)
|
||
|
|
for index, line := range footerLines {
|
||
|
|
fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#747c7d" font-family="Georgia, 'Times New Roman', serif" font-size="9">%s</text>`,
|
||
|
|
layout.margin, layout.footerY+float64(len(directionLines))*14+float64(index)*12-6, html.EscapeString(line))
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGEventFrames(
|
||
|
|
info moon.StarOccultationInfo,
|
||
|
|
frames []moon.StarOccultationDiagramFrame,
|
||
|
|
language string,
|
||
|
|
) []localStarOccultationEventFrame {
|
||
|
|
times := map[string]time.Time{
|
||
|
|
"Immersion": info.Immersion,
|
||
|
|
"Greatest": info.Greatest,
|
||
|
|
"Emersion": info.Emersion,
|
||
|
|
}
|
||
|
|
labels := []string{"Immersion", "Greatest", "Emersion"}
|
||
|
|
result := make([]localStarOccultationEventFrame, 0, len(labels))
|
||
|
|
for _, label := range labels {
|
||
|
|
for _, frame := range frames {
|
||
|
|
if localStarOccultationSVGFrameHasLabel(frame, label) {
|
||
|
|
result = append(result, localStarOccultationEventFrame{
|
||
|
|
label: label,
|
||
|
|
name: localStarOccultationSVGEventName(label, language),
|
||
|
|
time: times[label],
|
||
|
|
frame: frame,
|
||
|
|
})
|
||
|
|
break
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return result
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGFrameHasLabel(frame moon.StarOccultationDiagramFrame, label string) bool {
|
||
|
|
if frame.Label == label {
|
||
|
|
return true
|
||
|
|
}
|
||
|
|
for _, current := range frame.Labels {
|
||
|
|
if current == label {
|
||
|
|
return true
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return false
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGHeaderLines(info moon.StarOccultationInfo, options LocalStarOccultationSVGOptions) []string {
|
||
|
|
lines := make([]string, 0, 4)
|
||
|
|
for _, value := range []string{
|
||
|
|
localStarOccultationSVGSummaryText(info, options),
|
||
|
|
localStarOccultationSVGGreatestText(info, options),
|
||
|
|
} {
|
||
|
|
lines = append(lines, starOccultationWrapText(value, float64(options.Width)-80, 13)...)
|
||
|
|
}
|
||
|
|
return lines
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGTitle(info moon.StarOccultationInfo, options LocalStarOccultationSVGOptions) string {
|
||
|
|
if options.Title != "" {
|
||
|
|
return options.Title
|
||
|
|
}
|
||
|
|
target := info.TargetID
|
||
|
|
if target == "" {
|
||
|
|
if options.Language == starOccultationSVGLanguageEnglish {
|
||
|
|
target = "star"
|
||
|
|
} else {
|
||
|
|
target = "恒星"
|
||
|
|
}
|
||
|
|
}
|
||
|
|
date := info.Greatest.In(options.Location).Format("2006-01-02")
|
||
|
|
if options.Language == starOccultationSVGLanguageEnglish {
|
||
|
|
return fmt.Sprintf("%s Local Lunar Occultation of %s", date, target)
|
||
|
|
}
|
||
|
|
return fmt.Sprintf("%s 指定地点月掩%s", date, target)
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGSummaryText(info moon.StarOccultationInfo, options LocalStarOccultationSVGOptions) string {
|
||
|
|
if options.SummaryText != "" {
|
||
|
|
return options.SummaryText
|
||
|
|
}
|
||
|
|
coordinates := starOccultationFormatCoordinates(info.Observer.Longitude, info.Observer.Latitude)
|
||
|
|
duration := localStarOccultationSVGFormatDuration(info.Emersion.Sub(info.Immersion), options.Language)
|
||
|
|
if options.Language == starOccultationSVGLanguageEnglish {
|
||
|
|
return fmt.Sprintf("Site %s | elevation %.0f m | %s | duration %s", coordinates, info.Observer.Height,
|
||
|
|
localStarOccultationSVGTypeName(info.Type, options.Language), duration)
|
||
|
|
}
|
||
|
|
return fmt.Sprintf("观测点 %s | 海拔 %.0f 米 | %s | 掩星历时 %s", coordinates, info.Observer.Height,
|
||
|
|
localStarOccultationSVGTypeName(info.Type, options.Language), duration)
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGGreatestText(info moon.StarOccultationInfo, options LocalStarOccultationSVGOptions) string {
|
||
|
|
if options.GreatestText != "" {
|
||
|
|
return options.GreatestText
|
||
|
|
}
|
||
|
|
value := info.Greatest.In(options.Location)
|
||
|
|
zone := starOccultationLocationLabel(value, options.Location)
|
||
|
|
if options.Language == starOccultationSVGLanguageEnglish {
|
||
|
|
return fmt.Sprintf("Greatest %s %s | minimum separation %.2f arcsec | Moon altitude %+.1f° azimuth %.1f°",
|
||
|
|
value.Format("2006-01-02 15:04:05.0"), zone, info.MinimumSeparationArcsec, info.MoonAltitudeAtGreatest, info.MoonAzimuthAtGreatest)
|
||
|
|
}
|
||
|
|
return fmt.Sprintf("掩甚 %s %s | 最小角距 %.2f 角秒 | 月球高度 %+.1f° 方位 %.1f°",
|
||
|
|
value.Format("2006-01-02 15:04:05.0"), zone, info.MinimumSeparationArcsec, info.MoonAltitudeAtGreatest, info.MoonAzimuthAtGreatest)
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGOverviewTitle(options LocalStarOccultationSVGOptions) string {
|
||
|
|
if options.OverviewTitle != "" {
|
||
|
|
return options.OverviewTitle
|
||
|
|
}
|
||
|
|
if options.Language == starOccultationSVGLanguageEnglish {
|
||
|
|
return "Topocentric star track"
|
||
|
|
}
|
||
|
|
return "站心恒星轨迹"
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGPhasePanelsTitle(options LocalStarOccultationSVGOptions) string {
|
||
|
|
if options.PhasePanelsTitle != "" {
|
||
|
|
return options.PhasePanelsTitle
|
||
|
|
}
|
||
|
|
if options.Language == starOccultationSVGLanguageEnglish {
|
||
|
|
return "Contact stages"
|
||
|
|
}
|
||
|
|
return "掩始、掩甚与掩终视圆"
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGContactsTitle(options LocalStarOccultationSVGOptions) string {
|
||
|
|
if options.ContactsTitle != "" {
|
||
|
|
return options.ContactsTitle
|
||
|
|
}
|
||
|
|
if options.Language == starOccultationSVGLanguageEnglish {
|
||
|
|
return "Local contacts"
|
||
|
|
}
|
||
|
|
return "本地接触时刻"
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGDirectionText(options LocalStarOccultationSVGOptions) string {
|
||
|
|
if options.DirectionText != "" {
|
||
|
|
return options.DirectionText
|
||
|
|
}
|
||
|
|
if options.Language == starOccultationSVGLanguageEnglish {
|
||
|
|
return "Moon fixed at center; east is left and north is up. The blue-gray dashed line is the local lunar path; the red dashed line is the star track."
|
||
|
|
}
|
||
|
|
return "月球固定在中心；图上左东右西，向上为北。灰蓝虚线为掩甚附近的站心白道，红色虚线为恒星相对月心轨迹。"
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGFooterNote(options LocalStarOccultationSVGOptions) string {
|
||
|
|
if options.FooterNote != "" {
|
||
|
|
return options.FooterNote
|
||
|
|
}
|
||
|
|
if options.Language == starOccultationSVGLanguageEnglish {
|
||
|
|
return "The star is a point source; immersion and emersion occur where it crosses the topocentric apparent lunar limb. Lunar texture is schematic."
|
||
|
|
}
|
||
|
|
return "恒星按点光源绘制；掩始和掩终是恒星穿越站心月球视圆外缘的时刻，月面纹理仅作方向辅助。"
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGEventName(label, language string) string {
|
||
|
|
if language == starOccultationSVGLanguageEnglish {
|
||
|
|
switch label {
|
||
|
|
case "Immersion":
|
||
|
|
return "Immersion"
|
||
|
|
case "Greatest":
|
||
|
|
return "Greatest"
|
||
|
|
case "Emersion":
|
||
|
|
return "Emersion"
|
||
|
|
}
|
||
|
|
}
|
||
|
|
switch label {
|
||
|
|
case "Immersion":
|
||
|
|
return "掩始"
|
||
|
|
case "Greatest":
|
||
|
|
return "掩甚"
|
||
|
|
case "Emersion":
|
||
|
|
return "掩终"
|
||
|
|
default:
|
||
|
|
return label
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGTypeName(eventType moon.OccultationType, language string) string {
|
||
|
|
if language == starOccultationSVGLanguageEnglish {
|
||
|
|
if eventType == moon.OccultationGrazing {
|
||
|
|
return "grazing"
|
||
|
|
}
|
||
|
|
return "total"
|
||
|
|
}
|
||
|
|
if eventType == moon.OccultationGrazing {
|
||
|
|
return "擦边掩星"
|
||
|
|
}
|
||
|
|
return "全掩"
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGFormatDuration(duration time.Duration, language string) string {
|
||
|
|
if duration < 0 {
|
||
|
|
duration = -duration
|
||
|
|
}
|
||
|
|
duration = duration.Round(100 * time.Millisecond)
|
||
|
|
hours := int(duration / time.Hour)
|
||
|
|
duration -= time.Duration(hours) * time.Hour
|
||
|
|
minutes := int(duration / time.Minute)
|
||
|
|
duration -= time.Duration(minutes) * time.Minute
|
||
|
|
seconds := float64(duration) / float64(time.Second)
|
||
|
|
if language == starOccultationSVGLanguageEnglish {
|
||
|
|
if hours > 0 {
|
||
|
|
return fmt.Sprintf("%dh %02dm %04.1fs", hours, minutes, seconds)
|
||
|
|
}
|
||
|
|
return fmt.Sprintf("%dm %04.1fs", minutes, seconds)
|
||
|
|
}
|
||
|
|
if hours > 0 {
|
||
|
|
return fmt.Sprintf("%d时%02d分%04.1f秒", hours, minutes, seconds)
|
||
|
|
}
|
||
|
|
return fmt.Sprintf("%d分%04.1f秒", minutes, seconds)
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGAltitudeLabel(language string) string {
|
||
|
|
if language == starOccultationSVGLanguageEnglish {
|
||
|
|
return "alt"
|
||
|
|
}
|
||
|
|
return "高度"
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGAzimuthLabel(language string) string {
|
||
|
|
if language == starOccultationSVGLanguageEnglish {
|
||
|
|
return "az"
|
||
|
|
}
|
||
|
|
return "方位"
|
||
|
|
}
|
||
|
|
|
||
|
|
func localStarOccultationSVGVisibilityText(visible bool, language string) string {
|
||
|
|
if language == starOccultationSVGLanguageEnglish {
|
||
|
|
if visible {
|
||
|
|
return "above horizon"
|
||
|
|
}
|
||
|
|
return "below horizon"
|
||
|
|
}
|
||
|
|
if visible {
|
||
|
|
return "地平线上"
|
||
|
|
}
|
||
|
|
return "地平线下"
|
||
|
|
}
|