feat: 完善日月食与月掩几何链路并扩展历法接口
- 新增日月食中心带、偏食带、阴影足迹、等时线、食分线及升落边界计算，支持极区与混合食拓扑 - 新增日食单时刻阴影求解器、站心状态查询、批量采样和 ΔT 覆盖接口 - 重构恒星与行星月掩路径，补充有限盘面接触、站心修正、掩带宽度、极区投影及升落边界 - 扩展 SVG 与 GeoJSON 输出，支持详细面板、全球/极区/地球投影、边界闭合、时间标记和拓扑签名 - 扩展日月食候选搜索、局地搜索、沙罗序列预计算与范围外推，补充系列锚点和成员一致性校验 - 补齐古历纪年、儒略历独有闰日、多公历候选、历法改革跨日及精确日期运算接口 - 优化 ΔT、章动、恒星时、月球地平线、事件根搜索和本地星历缓存，降低重复计算开销并提升边界稳定
This commit is contained in:
@@ -0,0 +1,127 @@
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package svgchart
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// LabelBox 是文本或图形占位的保守包围盒。/ LabelBox is a conservative bounding box for a reserved label or graphic.
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type LabelBox struct {
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X, Y, Width, Height float64
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}
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// LabelPlacement 是一个候选位次：文本锚点与 text-anchor 取值。
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// LabelPlacement is one candidate slot: the text anchor point and its text-anchor value.
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type LabelPlacement struct {
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X, Y float64
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Anchor string
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}
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// LabelTable 记录已占位的矩形，后来的标签按候选顺序避让。
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// LabelTable records reserved rectangles; later labels avoid them in candidate order.
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type LabelTable struct {
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boxes []LabelBox
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}
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// labelClearance 是落位判定要求的间隙：包围盒各向外放 1 px，写出的坐标取整后两个盒子也不会贴成相交。
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const labelClearance = 1.0
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// Reserve 占位一个矩形；非正宽高直接忽略。
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// Reserve claims a rectangle; non-positive extents are ignored.
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func (table *LabelTable) Reserve(x, y, width, height float64) {
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if width <= 0 || height <= 0 {
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return
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}
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table.boxes = append(table.boxes, LabelBox{X: x, Y: y, Width: width, Height: height})
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}
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// LabelTextBox 返回文本的保守包围盒，anchor 取 start、middle 或 end。
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// LabelTextBox returns a text's conservative box for a start, middle, or end anchor.
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func LabelTextBox(x, baseline, fontSize float64, text, anchor string) LabelBox {
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if fontSize <= 0 {
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fontSize = 12
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}
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width := EstimatedTextWidth(text, fontSize)
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left := x
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switch anchor {
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case "middle":
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left = x - width/2
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case "end":
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left = x - width
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}
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above, below := EstimatedTextExtents(fontSize)
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return LabelBox{X: left, Y: baseline - above, Width: width, Height: above + below}
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}
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// ReserveText 占位一段文本并返回它的包围盒。
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// ReserveText claims a text box and returns it.
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func (table *LabelTable) ReserveText(x, baseline, fontSize float64, text, anchor string) LabelBox {
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box := LabelTextBox(x, baseline, fontSize, text, anchor)
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table.Reserve(box.X, box.Y, box.Width, box.Height)
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return box
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}
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// Overlaps 报告矩形是否压到已占位矩形；两个盒子之间至少留 labelClearance。
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// Overlaps reports whether a rectangle collides with any reserved box, keeping labelClearance between them.
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func (table *LabelTable) Overlaps(x, y, width, height float64) bool {
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for _, box := range table.boxes {
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if box.X+box.Width+labelClearance <= x || x+width+labelClearance <= box.X {
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continue
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}
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if box.Y+box.Height+labelClearance <= y || y+height+labelClearance <= box.Y {
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continue
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}
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return true
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}
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return false
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}
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// OverlapsText 报告文本是否压到已占位矩形。
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// OverlapsText reports whether a text collides with any reserved box.
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func (table *LabelTable) OverlapsText(x, baseline, fontSize float64, text, anchor string) bool {
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box := LabelTextBox(x, baseline, fontSize, text, anchor)
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return table.Overlaps(box.X, box.Y, box.Width, box.Height)
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}
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// Place 按候选顺序放一段文本：返回首个不压叠的位次并占位；全部压叠时返回 false 且不占位。
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// Place takes the first candidate that keeps the text clear, claims it, and reports false when none does.
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func (table *LabelTable) Place(text string, fontSize float64, candidates []LabelPlacement) (LabelPlacement, bool) {
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for _, candidate := range candidates {
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box := LabelTextBox(candidate.X, candidate.Y, fontSize, text, candidate.Anchor)
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if table.Overlaps(box.X, box.Y, box.Width, box.Height) {
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continue
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}
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table.Reserve(box.X, box.Y, box.Width, box.Height)
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return candidate, true
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}
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return LabelPlacement{}, false
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}
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// MirrorLabelAnchor 返回镜像后的 text-anchor：start 与 end 互换，middle 不变。
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// MirrorLabelAnchor flips start and end, and keeps middle.
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func MirrorLabelAnchor(anchor string) string {
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switch anchor {
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case "start":
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return "end"
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case "end":
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return "start"
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default:
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return "middle"
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}
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}
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// LabelCandidates 生成绕锚点的候选位次：原位、上下左右、四角，再按镜像 anchor 重复一遍。
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// LabelCandidates lists candidate slots around an anchor: in place, then the four sides, then the
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// four corners, repeated for the mirrored anchor.
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func LabelCandidates(x, y float64, anchor string, radius float64) []LabelPlacement {
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candidates := make([]LabelPlacement, 0, 18)
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for _, current := range []string{anchor, MirrorLabelAnchor(anchor)} {
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candidates = append(candidates,
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LabelPlacement{X: x, Y: y, Anchor: current},
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LabelPlacement{X: x, Y: y - radius, Anchor: current},
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LabelPlacement{X: x, Y: y + radius, Anchor: current},
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LabelPlacement{X: x + radius, Y: y, Anchor: current},
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LabelPlacement{X: x - radius, Y: y, Anchor: current},
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LabelPlacement{X: x + radius, Y: y - radius, Anchor: current},
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LabelPlacement{X: x - radius, Y: y - radius, Anchor: current},
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LabelPlacement{X: x + radius, Y: y + radius, Anchor: current},
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LabelPlacement{X: x - radius, Y: y + radius, Anchor: current},
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)
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}
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return candidates
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}
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@@ -0,0 +1,162 @@
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// Package svgchart 提供日月食与月掩星详细版式共用的数据块与版面计算。
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// Package svgchart holds the data blocks and page geometry shared by the detailed eclipse and occultation charts.
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package svgchart
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import (
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"fmt"
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"html"
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"math"
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"strings"
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)
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// PanelRow 是数据块里的一行；Detail 非空时在数值下方补一行灰色小字。
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type PanelRow struct {
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Label string
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Value string
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Detail string
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}
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// PanelBlock 是一个带标题的数据块。
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type PanelBlock struct {
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Title string
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Rows []PanelRow
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}
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// WritePanelBox 画一个数据块：标题加若干行“标签 + 数值”。
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// 行高按行数等分，因此块高变化时不会溢出；Class 用于区分各族图的样式钩子。
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func WritePanelBox(
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b *strings.Builder,
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class string,
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x, y, width, height float64,
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title string,
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rows []PanelRow,
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) {
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if len(rows) == 0 || height <= 0 {
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return
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}
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fmt.Fprintf(b, `<g class="%s">`, class)
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fmt.Fprintf(b, `<rect x="%.3f" y="%.3f" width="%.3f" height="%.3f" rx="3" fill="#fbfcfd" stroke="#dde3e9"/>`,
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x, y, width, height)
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fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#111827" font-family="Georgia, 'Times New Roman', serif" font-size="12" font-weight="700">%s</text>`,
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x+12, y+20, html.EscapeString(title))
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rowHeight := (height - panelBoxHeaderHeight) / float64(len(rows))
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for index, row := range rows {
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if row.Label == "" {
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continue
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}
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rowY := y + panelBoxHeaderHeight + float64(index)*rowHeight
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size := PanelRowFontSize(width, row)
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fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#475569" font-family="Arial, sans-serif" font-size="%.1f">%s</text>`,
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x+panelBoxPadding, rowY+11, size, html.EscapeString(row.Label))
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fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#0f172a" font-family="Arial, sans-serif" font-size="%.1f" font-weight="700" text-anchor="end">%s</text>`,
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x+width-panelBoxPadding, rowY+11, size, html.EscapeString(row.Value))
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if row.Detail != "" {
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fmt.Fprintf(b, `<text x="%.3f" y="%.3f" fill="#7b8794" font-family="Arial, sans-serif" font-size="%d">%s</text>`,
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x+panelBoxPadding, rowY+22, panelRowDetailSize, html.EscapeString(row.Detail))
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}
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}
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b.WriteString(`</g>`)
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}
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const (
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panelBoxHeaderHeight = 30
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panelRowLabelSize = 10.5
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panelRowDetailSize = 9
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panelBoxPadding = 12
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panelLabelValueGap = 8
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panelMinimumFontSize = 8
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)
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// EstimatedTextWidth 按字号估算文本宽度：ASCII 取 0.62em，非 ASCII（含全角中文）取 1.05em。
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// 没有字体度量可用，这里只服务于压叠判定，估值偏大以保证判定保守。
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// EstimatedTextWidth estimates text width from the font size: 0.62em per ASCII rune and 1.05em
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// otherwise. It exists only for overlap checks, so it deliberately over-estimates.
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func EstimatedTextWidth(text string, fontSize float64) float64 {
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units := 0.0
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for _, symbol := range text {
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if symbol < 128 {
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units += 0.62
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continue
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}
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units += 1.05
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}
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return units * fontSize
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}
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// EstimatedTextExtents 返回文本相对基线的上下留白，用于构造占位矩形。
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// EstimatedTextExtents returns the space a text keeps above and below its baseline.
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func EstimatedTextExtents(fontSize float64) (above, below float64) {
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return 0.85 * fontSize, 0.30 * fontSize
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}
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// PanelRowFontSize 返回该行“标签 + 数值”放不下时等比缩小后的字号；缩小到下限仍放不下说明块太窄。
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// PanelRowFontSize shrinks a row's font until its label and value fit side by side.
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func PanelRowFontSize(width float64, row PanelRow) float64 {
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content := width - 2*panelBoxPadding
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if content <= 0 {
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return panelMinimumFontSize
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}
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pair := EstimatedTextWidth(row.Label, panelRowLabelSize) + EstimatedTextWidth(row.Value, panelRowLabelSize)
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if pair+panelLabelValueGap <= content {
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return panelRowLabelSize
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}
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size := panelRowLabelSize * (content - panelLabelValueGap) / pair
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if size < panelMinimumFontSize {
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return panelMinimumFontSize
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}
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return size
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}
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func panelTextRect(x, baseline, fontSize float64, text string, anchorEnd bool) panelTextBox {
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width := EstimatedTextWidth(text, fontSize)
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left := x
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if anchorEnd {
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left = x - width
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}
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above, below := EstimatedTextExtents(fontSize)
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return panelTextBox{x: left, y: baseline - above, width: width, height: above + below}
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}
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// panelTextBox 是文本的保守包围盒。
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type panelTextBox struct {
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x, y, width, height float64
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}
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func panelTextBoxesOverlap(first, second panelTextBox) bool {
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left, right := math.Max(first.x, second.x), math.Min(first.x+first.width, second.x+second.width)
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top, bottom := math.Max(first.y, second.y), math.Min(first.y+first.height, second.y+second.height)
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return right-left > 0.5 && bottom-top > 0
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}
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// PanelBoxOverlaps 报告该块在给定位次与尺寸下，块内文本是否会互相压叠。
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// 行高按行数等分，所以块太矮时行距会小于文字高度，此时必须由调用方拒绝该画布而不是画出压叠的文字。
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// PanelBoxOverlaps reports whether the block's own texts would collide at the given box; callers must
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// reject a canvas whose panels cannot keep the rows apart.
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func PanelBoxOverlaps(x, y, width, height float64, title string, rows []PanelRow) bool {
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if len(rows) == 0 || height <= 0 {
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return false
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}
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boxes := make([]panelTextBox, 0, 2*len(rows)+1)
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boxes = append(boxes, panelTextRect(x+12, y+20, 12, title, false))
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rowHeight := (height - panelBoxHeaderHeight) / float64(len(rows))
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for index, row := range rows {
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if row.Label == "" {
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continue
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}
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rowY := y + panelBoxHeaderHeight + float64(index)*rowHeight
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size := PanelRowFontSize(width, row)
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boxes = append(boxes, panelTextRect(x+panelBoxPadding, rowY+11, size, row.Label, false))
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boxes = append(boxes, panelTextRect(x+width-panelBoxPadding, rowY+11, size, row.Value, true))
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if row.Detail != "" {
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boxes = append(boxes, panelTextRect(x+panelBoxPadding, rowY+22, panelRowDetailSize, row.Detail, false))
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}
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}
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for first := 0; first < len(boxes); first++ {
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for second := first + 1; second < len(boxes); second++ {
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if panelTextBoxesOverlap(boxes[first], boxes[second]) {
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return true
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}
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}
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}
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return false
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}
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@@ -0,0 +1,75 @@
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package svgchart
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import (
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"math"
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"strings"
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"testing"
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)
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func TestEstimatedTextWidthUsesSeparateAsciiAndWideRuneUnits(t *testing.T) {
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if got := EstimatedTextWidth("", 10); got != 0 {
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t.Fatalf("empty text width = %v, want 0", got)
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}
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if got := EstimatedTextWidth("AB", 10); math.Abs(got-12.4) > 1e-9 {
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t.Fatalf("two ASCII runes = %v, want 12.4", got)
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}
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if got := EstimatedTextWidth("中文", 10); math.Abs(got-21) > 1e-9 {
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t.Fatalf("two wide runes = %v, want 21", got)
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}
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above, below := EstimatedTextExtents(10)
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if math.Abs(above-8.5) > 1e-9 || math.Abs(below-3) > 1e-9 {
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t.Fatalf("extents = %v/%v, want 8.5/3", above, below)
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}
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}
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func TestPanelRowFontSizeShrinksUntilLabelAndValueFit(t *testing.T) {
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row := PanelRow{Label: "地平视差 H.P.", Value: "00°16'21.4\""}
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if got := PanelRowFontSize(320, row); got != panelRowLabelSize {
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t.Fatalf("wide box font = %v, want the base size", got)
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}
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narrow := 170.0
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size := PanelRowFontSize(narrow, row)
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if size >= panelRowLabelSize || size < panelMinimumFontSize {
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t.Fatalf("narrow box font = %v, want a size in [%v,%v)", size, panelMinimumFontSize, panelRowLabelSize)
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}
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content := narrow - 2*panelBoxPadding
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pair := EstimatedTextWidth(row.Label, size) + EstimatedTextWidth(row.Value, size)
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if pair+panelLabelValueGap > content {
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t.Fatalf("shrunk label %v + value %v + gap does not fit %v", pair, panelLabelValueGap, content)
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}
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}
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func TestPanelBoxOverlapsDetectsCrowdedRows(t *testing.T) {
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rows := []PanelRow{
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{Label: "赤经 R.A.", Value: "23h21m52.2s"},
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{Label: "赤纬 Dec.", Value: "-05°59'26.5\""},
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{Label: "掩甚", Value: "04:28:23", Detail: "90.9407°E, 11.7283°N"},
|
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{Label: "视半径 S.D.", Value: "00°16'21.4\""},
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}
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if PanelBoxOverlaps(0, 0, 230, 200, "月亮（地心坐标）", rows) {
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t.Fatal("tall box reported overlapping rows")
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}
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if !PanelBoxOverlaps(0, 0, 230, 34, "月亮（地心坐标）", rows) {
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t.Fatal("box too short for its rows reported no overlap")
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}
|
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if !PanelBoxOverlaps(0, 0, 120, 200, "月亮（地心坐标）", rows) {
|
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t.Fatal("box too narrow for label and value reported no overlap")
|
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}
|
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if PanelBoxOverlaps(0, 0, 230, 200, "标题", nil) {
|
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t.Fatal("empty block reported an overlap")
|
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}
|
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}
|
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|
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func TestWritePanelBoxKeepsEveryTextInsideTheBlockWidth(t *testing.T) {
|
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row := PanelRow{Label: "地平视差 H.P.", Value: "00°16'21.4\""}
|
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var builder strings.Builder
|
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WritePanelBox(&builder, "panel", 0, 0, 170, 200, "月亮（地心坐标）", []PanelRow{row})
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document := builder.String()
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labelX := strings.Index(document, `x="12.000"`)
|
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if labelX < 0 {
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t.Fatalf("label is not drawn at the block padding: %s", document)
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}
|
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if !strings.Contains(document, `text-anchor="end"`) {
|
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t.Fatalf("value is not right-anchored: %s", document)
|
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}
|
||||
}
|
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@@ -0,0 +1,118 @@
|
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package svgchart
|
||||
|
||||
import (
|
||||
"math"
|
||||
"strings"
|
||||
"unicode"
|
||||
)
|
||||
|
||||
// ellipsisMark 是截断标记；用单个全角省略号，避免与文本里的三个半角点混淆。
|
||||
const ellipsisMark = "…"
|
||||
|
||||
// estimatedTextRuneWidth 与 EstimatedTextWidth 的逐字符口径必须一致，否则折行结果会与占位判定矛盾。
|
||||
func estimatedTextRuneWidth(symbol rune, fontSize float64) float64 {
|
||||
if symbol < 128 {
|
||||
return 0.62 * fontSize
|
||||
}
|
||||
return 1.05 * fontSize
|
||||
}
|
||||
|
||||
// EllipsizeText 把单行文本裁到 maxWidth 内：放不下时保留前缀并追加省略号，全空的返回值表示连省略号都放不下。
|
||||
// EllipsizeText clamps one line to maxWidth, appending an ellipsis when the text does not fit;
|
||||
// an empty result means even the ellipsis does not fit.
|
||||
func EllipsizeText(value string, maxWidth, fontSize float64) string {
|
||||
if EstimatedTextWidth(value, fontSize) <= maxWidth {
|
||||
return value
|
||||
}
|
||||
return truncateWithMark(value, maxWidth, fontSize)
|
||||
}
|
||||
|
||||
// truncateWithMark 无条件追加省略号：被截断的行即使本身放得下，也必须标出后面还有内容。
|
||||
func truncateWithMark(value string, maxWidth, fontSize float64) string {
|
||||
markWidth := EstimatedTextWidth(ellipsisMark, fontSize)
|
||||
if markWidth > maxWidth {
|
||||
return ""
|
||||
}
|
||||
runes := []rune(value)
|
||||
for len(runes) > 0 && EstimatedTextWidth(string(runes), fontSize)+markWidth > maxWidth {
|
||||
runes = runes[:len(runes)-1]
|
||||
}
|
||||
return strings.TrimRight(string(runes), " ") + ellipsisMark
|
||||
}
|
||||
|
||||
// WrapText 按 EstimatedTextWidth 保守折行：优先在空白处断开，单个词或全角文本按字符断开，空行不返回。
|
||||
// WrapText wraps conservatively by EstimatedTextWidth, preferring whitespace breaks; empty lines are dropped.
|
||||
func WrapText(value string, maxWidth, fontSize float64) []string {
|
||||
value = strings.TrimSpace(value)
|
||||
if value == "" {
|
||||
return nil
|
||||
}
|
||||
if EstimatedTextWidth(value, fontSize) <= maxWidth {
|
||||
return []string{value}
|
||||
}
|
||||
runes := []rune(value)
|
||||
lines := make([]string, 0, 4)
|
||||
for len(runes) > 0 {
|
||||
width := 0.0
|
||||
end := 0
|
||||
lastSpace := -1
|
||||
for end < len(runes) {
|
||||
nextWidth := width + estimatedTextRuneWidth(runes[end], fontSize)
|
||||
if nextWidth > maxWidth && end > 0 {
|
||||
break
|
||||
}
|
||||
width = nextWidth
|
||||
if unicode.IsSpace(runes[end]) {
|
||||
lastSpace = end
|
||||
}
|
||||
end++
|
||||
}
|
||||
if end < len(runes) && lastSpace > 0 {
|
||||
end = lastSpace
|
||||
}
|
||||
if end == 0 {
|
||||
end = 1
|
||||
}
|
||||
if line := strings.TrimSpace(string(runes[:end])); line != "" {
|
||||
lines = append(lines, line)
|
||||
}
|
||||
runes = runes[end:]
|
||||
for len(runes) > 0 && unicode.IsSpace(runes[0]) {
|
||||
runes = runes[1:]
|
||||
}
|
||||
}
|
||||
return lines
|
||||
}
|
||||
|
||||
// TextLineLimit 返回高度预算 maxHeight 能容纳的行数，至少一行；口径与 EstimatedTextExtents 一致。
|
||||
// TextLineLimit reports how many lines fit in maxHeight, never less than one.
|
||||
func TextLineLimit(fontSize, lineHeight, maxHeight float64) int {
|
||||
if lineHeight <= 0 {
|
||||
lineHeight = 1.2 * fontSize
|
||||
}
|
||||
above, below := EstimatedTextExtents(fontSize)
|
||||
limit := int(math.Floor((maxHeight-above-below)/lineHeight)) + 1
|
||||
if limit < 1 {
|
||||
return 1
|
||||
}
|
||||
return limit
|
||||
}
|
||||
|
||||
// BaselineLineLimit 返回自 firstBaseline 起、底线 bottomLimit 之前能排下的行数，至少一行。
|
||||
// BaselineLineLimit reports how many lines fit below firstBaseline and above bottomLimit, never less than one.
|
||||
func BaselineLineLimit(fontSize, lineHeight, firstBaseline, bottomLimit float64) int {
|
||||
above, _ := EstimatedTextExtents(fontSize)
|
||||
return TextLineLimit(fontSize, lineHeight, bottomLimit-firstBaseline+above)
|
||||
}
|
||||
|
||||
// TruncateTextLines 按行数上限截断折行结果：截断时末行以省略号结尾并重新裁到 maxWidth 内，未截断时原样返回。
|
||||
// TruncateTextLines cuts lines to maxLines; a cut last line is ellipsized to maxWidth.
|
||||
func TruncateTextLines(lines []string, maxWidth, fontSize float64, maxLines int) []string {
|
||||
if len(lines) == 0 || maxLines <= 0 || len(lines) <= maxLines {
|
||||
return lines
|
||||
}
|
||||
kept := make([]string, maxLines)
|
||||
copy(kept, lines[:maxLines])
|
||||
kept[maxLines-1] = truncateWithMark(kept[maxLines-1], maxWidth, fontSize)
|
||||
return kept
|
||||
}
|
||||
@@ -0,0 +1,108 @@
|
||||
package svgchart
|
||||
|
||||
import (
|
||||
"strings"
|
||||
"testing"
|
||||
)
|
||||
|
||||
// 折行与截断必须与 EstimatedTextWidth/EstimatedTextExtents 同口径：留下的每一行都不超宽，
|
||||
// 截断后的行数不超过高度预算，且末行以省略号结尾。
|
||||
|
||||
func textFits(t *testing.T, lines []string, maxWidth, fontSize float64) {
|
||||
t.Helper()
|
||||
for _, line := range lines {
|
||||
if width := EstimatedTextWidth(line, fontSize); width > maxWidth {
|
||||
t.Fatalf("line %q width %.1f exceeds %.1f", line, width, maxWidth)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestWrapTextKeepsEveryLineInsideWidth(t *testing.T) {
|
||||
for _, test := range []struct {
|
||||
name string
|
||||
value string
|
||||
maxWidth float64
|
||||
fontSize float64
|
||||
}{
|
||||
{name: "ascii words", value: strings.Repeat("alpha beta gamma ", 20), maxWidth: 220, fontSize: 11},
|
||||
{name: "chinese runs", value: strings.Repeat("月球掩星示意图说明", 30), maxWidth: 180, fontSize: 11},
|
||||
{name: "mixed", value: strings.Repeat("掩星 occultation 说明；", 40), maxWidth: 260, fontSize: 9},
|
||||
{name: "single word", value: strings.Repeat("A", 200), maxWidth: 120, fontSize: 10},
|
||||
} {
|
||||
t.Run(test.name, func(t *testing.T) {
|
||||
lines := WrapText(test.value, test.maxWidth, test.fontSize)
|
||||
if len(lines) < 2 {
|
||||
t.Fatalf("lines = %d, want the text to be wrapped", len(lines))
|
||||
}
|
||||
textFits(t, lines, test.maxWidth, test.fontSize)
|
||||
})
|
||||
}
|
||||
}
|
||||
|
||||
func TestWrapTextKeepsShortTextOnOneLine(t *testing.T) {
|
||||
lines := WrapText(" 短说明 short note ", 400, 11)
|
||||
if len(lines) != 1 || lines[0] != "短说明 short note" {
|
||||
t.Fatalf("lines = %#v, want one trimmed line", lines)
|
||||
}
|
||||
if lines := WrapText(" ", 400, 11); lines != nil {
|
||||
t.Fatalf("blank text lines = %#v, want nil", lines)
|
||||
}
|
||||
}
|
||||
|
||||
func TestTruncateTextLinesMarksTheCut(t *testing.T) {
|
||||
lines := []string{"第一行", "第二行", "第三行", "第四行"}
|
||||
kept := TruncateTextLines(lines, 400, 11, 2)
|
||||
if len(kept) != 2 || kept[0] != "第一行" {
|
||||
t.Fatalf("kept = %#v, want the first two lines", kept)
|
||||
}
|
||||
if !strings.HasSuffix(kept[1], ellipsisMark) {
|
||||
t.Fatalf("last kept line = %q, want the ellipsis mark", kept[1])
|
||||
}
|
||||
if kept := TruncateTextLines(lines, 400, 11, 9); len(kept) != 4 || kept[3] != "第四行" {
|
||||
t.Fatalf("kept = %#v, want the untouched input", kept)
|
||||
}
|
||||
}
|
||||
|
||||
func TestTruncateTextLinesEllipsizesTheLastLineToWidth(t *testing.T) {
|
||||
lines := []string{strings.Repeat("宽", 20), strings.Repeat("宽", 20)}
|
||||
kept := TruncateTextLines(lines, 60, 10, 1)
|
||||
if len(kept) != 1 || !strings.HasSuffix(kept[0], ellipsisMark) {
|
||||
t.Fatalf("kept = %#v, want one ellipsized line", kept)
|
||||
}
|
||||
textFits(t, kept, 60, 10)
|
||||
}
|
||||
|
||||
func TestTextLineLimitCountsExtents(t *testing.T) {
|
||||
// 3 行 11 号字、行距 15 的总高约 42.65，预算再少一点就只放得下 2 行。
|
||||
if limit := TextLineLimit(11, 15, 42.7); limit != 3 {
|
||||
t.Fatalf("limit = %d, want 3", limit)
|
||||
}
|
||||
if limit := TextLineLimit(11, 15, 42.6); limit != 2 {
|
||||
t.Fatalf("limit = %d, want 2", limit)
|
||||
}
|
||||
if limit := TextLineLimit(11, 15, 1); limit != 1 {
|
||||
t.Fatalf("limit = %d, want the one-line floor", limit)
|
||||
}
|
||||
// 基线口径：首行基线 100，第 2 行要排得下需要底线不低于 100+15+0.3*11。
|
||||
if limit := BaselineLineLimit(11, 15, 100, 118.4); limit != 2 {
|
||||
t.Fatalf("limit = %d, want 2", limit)
|
||||
}
|
||||
if limit := BaselineLineLimit(11, 15, 100, 118.2); limit != 1 {
|
||||
t.Fatalf("limit = %d, want 1", limit)
|
||||
}
|
||||
}
|
||||
|
||||
func TestEllipsizeTextStaysInsideWidth(t *testing.T) {
|
||||
value := strings.Repeat("长文本 ellipsis ", 30)
|
||||
clamped := EllipsizeText(value, 150, 11)
|
||||
if !strings.HasSuffix(clamped, ellipsisMark) {
|
||||
t.Fatalf("clamped = %q, want the ellipsis mark", clamped)
|
||||
}
|
||||
textFits(t, []string{clamped}, 150, 11)
|
||||
if short := EllipsizeText("短", 150, 11); short != "短" {
|
||||
t.Fatalf("short text = %q, want it untouched", short)
|
||||
}
|
||||
if empty := EllipsizeText(value, 1, 11); empty != "" {
|
||||
t.Fatalf("clamped = %q, want an empty string when even the mark does not fit", empty)
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user