396 lines
13 KiB
Go
396 lines
13 KiB
Go
// Port of jsruntime/uikit/USHeatmap.tsx — a choropleth of the 50 states + DC, plus
|
||
// optional lat/lng markers, drawn by the WebAssembly. The state boundaries (usstates.go)
|
||
// are pre-projected with d3's albersUsa; the SAME projection is reimplemented below so a
|
||
// lat/lng point lands on top of the states — a faithful port validated to 0px against
|
||
// d3-geo (Alaska and Hawaii insets included).
|
||
//
|
||
// The map scales by viewBox (there is no axis text to keep crisp), so no measurement.
|
||
// Hover reads e.Target()'s data-attribute — the state path or point marker under the
|
||
// pointer — so no coordinate maths is needed to know what is being pointed at; the tooltip
|
||
// anchors to the hovered state's centroid (or the point), drawn into the same SVG.
|
||
package webui
|
||
|
||
import (
|
||
"math"
|
||
"sort"
|
||
"strconv"
|
||
"strings"
|
||
|
||
"kjol/vdom"
|
||
"kjol/wasmruntime"
|
||
)
|
||
|
||
// ── the albersUsa projection (ported from d3-geo; scale 1280, translate [480,300]) ──────
|
||
|
||
const (
|
||
usRad = math.Pi / 180
|
||
usTau = 2 * math.Pi
|
||
usK = 1280.0
|
||
usTX = 480.0
|
||
usTY = 300.0
|
||
usEps = 1e-6
|
||
)
|
||
|
||
func conicEqualAreaRaw(y0, y1 float64) func(lambda, phi float64) (float64, float64) {
|
||
sy0 := math.Sin(y0)
|
||
n := (sy0 + math.Sin(y1)) / 2
|
||
c := 1 + sy0*(2*n-sy0)
|
||
r0 := math.Sqrt(c) / n
|
||
return func(lambda, phi float64) (float64, float64) {
|
||
r := math.Sqrt(c-2*n*math.Sin(phi)) / n
|
||
return r * math.Sin(lambda*n), r0 - r*math.Cos(lambda*n)
|
||
}
|
||
}
|
||
|
||
// albersLobe is one conic-equal-area lobe. center is in the rotated frame (near 0° lon),
|
||
// so it is not re-rotated; the input point is rotated by rotateLon before projecting.
|
||
func albersLobe(rotateLon, centerLon, centerLat, p0, p1, scale, tx, ty float64) func(lon, lat float64) (float64, float64) {
|
||
raw := conicEqualAreaRaw(p0*usRad, p1*usRad)
|
||
rot := func(lon float64) float64 {
|
||
l := (lon + rotateLon) * usRad
|
||
return math.Mod(math.Mod(l+math.Pi, usTau)+usTau, usTau) - math.Pi
|
||
}
|
||
cx, cy := raw(centerLon*usRad, centerLat*usRad)
|
||
return func(lon, lat float64) (float64, float64) {
|
||
x, y := raw(rot(lon), lat*usRad)
|
||
return tx + scale*(x-cx), ty - scale*(y-cy)
|
||
}
|
||
}
|
||
|
||
var (
|
||
usLower48 = albersLobe(96, -0.6, 38.7, 29.5, 45.5, usK, usTX, usTY)
|
||
usAlaska = albersLobe(154, -2, 58.5, 55, 65, usK*0.35, usTX-0.307*usK, usTY+0.201*usK)
|
||
usHawaii = albersLobe(157, -3, 19.9, 8, 18, usK, usTX-0.205*usK, usTY+0.212*usK)
|
||
)
|
||
|
||
func usInBox(x, y, x0, y0, x1, y1 float64) bool {
|
||
return x >= x0 && x <= x1 && y >= y0 && y <= y1
|
||
}
|
||
|
||
// ProjectUS maps [lng, lat] to the 960×600 map, picking the lower-48 / Alaska / Hawaii
|
||
// lobe by which one's clip box the point falls in, the way albersUsa does. ok is false
|
||
// when the point is off-map.
|
||
func ProjectUS(lng, lat float64) (x, y float64, ok bool) {
|
||
x, y = usLower48(lng, lat)
|
||
if usInBox(x, y, usTX-0.455*usK, usTY-0.238*usK, usTX+0.455*usK, usTY+0.238*usK) {
|
||
return x, y, true
|
||
}
|
||
x, y = usAlaska(lng, lat)
|
||
if usInBox(x, y, usTX-0.425*usK+usEps, usTY+0.120*usK+usEps, usTX-0.214*usK-usEps, usTY+0.234*usK-usEps) {
|
||
return x, y, true
|
||
}
|
||
x, y = usHawaii(lng, lat)
|
||
if usInBox(x, y, usTX-0.214*usK+usEps, usTY+0.166*usK+usEps, usTX-0.115*usK-usEps, usTY+0.234*usK-usEps) {
|
||
return x, y, true
|
||
}
|
||
return 0, 0, false
|
||
}
|
||
|
||
// ── state centroids (bounding-box centre of each path, for the tooltip anchor) ──────
|
||
|
||
var usStateCodes = func() []string {
|
||
codes := make([]string, 0, len(usStates))
|
||
for c := range usStates {
|
||
codes = append(codes, c)
|
||
}
|
||
sort.Strings(codes)
|
||
return codes
|
||
}()
|
||
|
||
var usCentroids = map[string][2]float64{}
|
||
|
||
func stateCentroid(code string) (float64, float64) {
|
||
if c, ok := usCentroids[code]; ok {
|
||
return c[0], c[1]
|
||
}
|
||
nums := pathNums(usStates[code].D)
|
||
minX, minY, maxX, maxY := math.Inf(1), math.Inf(1), math.Inf(-1), math.Inf(-1)
|
||
for i := 0; i+1 < len(nums); i += 2 {
|
||
minX, maxX = math.Min(minX, nums[i]), math.Max(maxX, nums[i])
|
||
minY, maxY = math.Min(minY, nums[i+1]), math.Max(maxY, nums[i+1])
|
||
}
|
||
cx, cy := (minX+maxX)/2, (minY+maxY)/2
|
||
usCentroids[code] = [2]float64{cx, cy}
|
||
return cx, cy
|
||
}
|
||
|
||
// pathNums extracts every number from a path d string. The state coords are all positive
|
||
// (the albersUsa box is 0..960 × 0..600), comma/letter separated, so a simple digit-run
|
||
// scan suffices — no sign or exponent handling needed.
|
||
func pathNums(s string) []float64 {
|
||
var out []float64
|
||
for i := 0; i < len(s); {
|
||
if c := s[i]; (c >= '0' && c <= '9') || c == '.' {
|
||
j := i
|
||
for j < len(s) && ((s[j] >= '0' && s[j] <= '9') || s[j] == '.') {
|
||
j++
|
||
}
|
||
if f, err := strconv.ParseFloat(s[i:j], 64); err == nil {
|
||
out = append(out, f)
|
||
}
|
||
i = j
|
||
} else {
|
||
i++
|
||
}
|
||
}
|
||
return out
|
||
}
|
||
|
||
// ── the component ────────────────────────────────────────────────────────────────
|
||
|
||
type USHeatmapPoint struct {
|
||
Lat, Lng float64
|
||
Value float64
|
||
Label string
|
||
}
|
||
|
||
type USHeatmapProps struct {
|
||
// State value map: USPS code ("CA", "TX", "DC") → number. Present states are shaded on
|
||
// the sequential ramp; absent states get the no-data neutral.
|
||
Data map[string]float64
|
||
// lat/lng markers, projected onto the map. Points outside the US are dropped.
|
||
Points []USHeatmapPoint
|
||
|
||
Height float64 // px; 0 = size from container width (960:600 aspect).
|
||
Class string
|
||
Steps int // choropleth buckets 1–6 (default 6, the token count).
|
||
NoTooltip bool //
|
||
Proportional bool // scale each dot's AREA by its value (radius ∝ √value).
|
||
|
||
ValueFormat func(float64) string
|
||
PointColor string // default var(--color-chart-1)
|
||
PointRadius float64 // fixed radius (default 5); MAX radius when proportional.
|
||
PointOpacity float64 // default 0.85
|
||
StateName func(string) string
|
||
}
|
||
|
||
const choroplethSteps = 6 // must match --color-choropleth-1..N
|
||
|
||
type usHover struct {
|
||
kind string // "" | "state" | "point"
|
||
code string
|
||
idx int
|
||
}
|
||
|
||
// USHeatmap is a CONTROLLER (it holds the hover signal across renders). Build it once and
|
||
// call Render(props) each render.
|
||
type USHeatmap struct {
|
||
hover *vdom.Signal[usHover]
|
||
svgRef *vdom.Ref
|
||
tipRef *vdom.Ref // the HTML tooltip, positioned imperatively so it follows the cursor
|
||
props USHeatmapProps
|
||
}
|
||
|
||
func NewUSHeatmap() *USHeatmap {
|
||
return &USHeatmap{hover: vdom.NewSignal(usHover{}), svgRef: vdom.NewRef(), tipRef: vdom.NewRef()}
|
||
}
|
||
|
||
func (c *USHeatmap) setHover(h usHover) {
|
||
if h != c.hover.Get() {
|
||
c.hover.Set(h)
|
||
}
|
||
}
|
||
func (c *USHeatmap) onLeave() { c.setHover(usHover{}) }
|
||
|
||
func (c *USHeatmap) onMove(e vdom.Event) {
|
||
if c.props.NoTooltip {
|
||
return
|
||
}
|
||
var hv usHover
|
||
if s, ok := wasmruntime.ClosestAttr(e.Target(), "[data-pt]", "data-pt"); ok {
|
||
idx, _ := strconv.Atoi(s)
|
||
hv = usHover{kind: "point", idx: idx}
|
||
} else if code, ok := wasmruntime.ClosestAttr(e.Target(), "[data-state]", "data-state"); ok {
|
||
hv = usHover{kind: "state", code: code}
|
||
}
|
||
c.setHover(hv)
|
||
if hv.kind == "" {
|
||
return
|
||
}
|
||
// position the tooltip at the pointer (follows the cursor, like the Solid heatmap). The
|
||
// svg is at the wrapper's top-left, so pointer-minus-svg-rect is the tooltip's left/top.
|
||
r := wasmruntime.Measure(c.svgRef)
|
||
if r.Width == 0 {
|
||
return
|
||
}
|
||
wasmruntime.SetStyle(c.tipRef, "left", num(clampf(float64(e.ClientX())-r.X, 8, r.Width-8))+"px")
|
||
wasmruntime.SetStyle(c.tipRef, "top", num(clampf(float64(e.ClientY())-r.Y, 8, r.Height-8))+"px")
|
||
wasmruntime.SetStyle(c.tipRef, "transform", "translate(-50%, calc(-100% - 12px))")
|
||
}
|
||
|
||
// tooltipNode is the HTML tooltip (absolute, pointer-events-none), rendered every pass so
|
||
// its ref stays valid; onMove positions it imperatively. Hidden when nothing is hovered.
|
||
func (c *USHeatmap) tooltipNode(p USHeatmapProps, hv usHover, mn, mx float64, steps int) *vdom.VNode {
|
||
base := "pointer-events-none absolute z-10 min-w-28 max-w-64 rounded-default border border-line bg-surface px-3 py-2 text-ss shadow-lg"
|
||
if p.NoTooltip || hv.kind == "" {
|
||
return vdom.Div(vdom.WithRef(c.tipRef), vdom.Attr("class", cx(base, "hidden")))
|
||
}
|
||
var title, value, swatch string
|
||
if hv.kind == "state" {
|
||
title = c.stateName(hv.code)
|
||
if v, has := p.Data[hv.code]; has && !math.IsNaN(v) {
|
||
value = c.valFmt(v)
|
||
swatch = "var(--color-choropleth-" + strconv.Itoa(heatBucket(v, mn, mx, steps)) + ")"
|
||
} else {
|
||
value = "no data"
|
||
swatch = "var(--color-surface-strong)"
|
||
}
|
||
} else if hv.idx >= 0 && hv.idx < len(p.Points) {
|
||
pt := p.Points[hv.idx]
|
||
title = pt.Label
|
||
if title == "" {
|
||
title = strconv.FormatFloat(pt.Lat, 'f', 2, 64) + ", " + strconv.FormatFloat(pt.Lng, 'f', 2, 64)
|
||
}
|
||
value = c.valFmt(pt.Value)
|
||
swatch = p.PointColor
|
||
if swatch == "" {
|
||
swatch = "var(--color-chart-1)"
|
||
}
|
||
}
|
||
content := []*vdom.VNode{
|
||
vdom.Div(vdom.Attr("class", "flex items-center gap-2"),
|
||
swatchSpan(swatch),
|
||
vdom.Span(vdom.Attr("class", "font-medium text-ink"), vdom.Text(title))),
|
||
}
|
||
if value != "" {
|
||
content = append(content, vdom.Div(vdom.Attr("class", "mt-1 font-semibold text-ink"),
|
||
vdom.Attr("style", "font-variant-numeric:tabular-nums"), vdom.Text(value)))
|
||
}
|
||
return vdom.Div(kids([]vdom.Mod{vdom.WithRef(c.tipRef), vdom.Attr("class", base)}, content)...)
|
||
}
|
||
|
||
func (c *USHeatmap) valFmt(v float64) string {
|
||
if c.props.ValueFormat != nil {
|
||
return c.props.ValueFormat(v)
|
||
}
|
||
return groupNum(v)
|
||
}
|
||
|
||
func (c *USHeatmap) stateName(code string) string {
|
||
if c.props.StateName != nil {
|
||
return c.props.StateName(code)
|
||
}
|
||
if s, ok := usStates[code]; ok {
|
||
return s.Name
|
||
}
|
||
return code
|
||
}
|
||
|
||
func heatBucket(v, mn, mx float64, steps int) int {
|
||
t := 1.0
|
||
if mx > mn {
|
||
t = (v - mn) / (mx - mn)
|
||
}
|
||
return clampi(int(math.Floor(t*float64(steps))), 0, steps-1) + 1
|
||
}
|
||
|
||
func (c *USHeatmap) Render(p USHeatmapProps) *vdom.VNode {
|
||
c.props = p
|
||
hv := c.hover.Get()
|
||
steps := clampi(p.Steps, 1, choroplethSteps)
|
||
if p.Steps == 0 {
|
||
steps = choroplethSteps
|
||
}
|
||
|
||
mn, mx, hasData := math.Inf(1), math.Inf(-1), false
|
||
for _, v := range p.Data {
|
||
if !math.IsNaN(v) && !math.IsInf(v, 0) {
|
||
mn, mx, hasData = math.Min(mn, v), math.Max(mx, v), true
|
||
}
|
||
}
|
||
|
||
var b strings.Builder
|
||
// states (sorted for a stable diff order)
|
||
for _, code := range usStateCodes {
|
||
v, has := p.Data[code]
|
||
fill := "var(--color-surface-strong)"
|
||
if has && !math.IsNaN(v) {
|
||
fill = "var(--color-choropleth-" + strconv.Itoa(heatBucket(v, mn, mx, steps)) + ")"
|
||
}
|
||
op := "1"
|
||
if hv.kind == "state" && hv.code == code {
|
||
op = "0.82"
|
||
}
|
||
b.WriteString(`<path d="` + usStates[code].D + `" data-state="` + code + `" fill="` + fill + `" fill-opacity="` + op + `" stroke="var(--color-surface)" stroke-width="0.8"/>`)
|
||
}
|
||
|
||
// points
|
||
pc := p.PointColor
|
||
if pc == "" {
|
||
pc = "var(--color-chart-1)"
|
||
}
|
||
pop := p.PointOpacity
|
||
if pop == 0 {
|
||
pop = 0.85
|
||
}
|
||
maxR := p.PointRadius
|
||
if maxR == 0 {
|
||
if p.Proportional {
|
||
maxR = 16
|
||
} else {
|
||
maxR = 5
|
||
}
|
||
}
|
||
minR := math.Min(3, maxR*0.35)
|
||
maxV := 1.0
|
||
if p.Proportional {
|
||
for _, pt := range p.Points {
|
||
if pt.Value > maxV {
|
||
maxV = pt.Value
|
||
}
|
||
}
|
||
}
|
||
for i, pt := range p.Points {
|
||
x, y, ok := ProjectUS(pt.Lng, pt.Lat)
|
||
if !ok {
|
||
continue
|
||
}
|
||
r := maxR
|
||
if p.Proportional {
|
||
r = minR + (maxR-minR)*math.Sqrt(clampf(pt.Value/maxV, 0, 1))
|
||
}
|
||
if hv.kind == "point" && hv.idx == i {
|
||
r += 2
|
||
}
|
||
b.WriteString(`<circle data-pt="` + strconv.Itoa(i) + `" cx="` + num(x) + `" cy="` + num(y) + `" r="` + num(r) + `" fill="` + svgEsc(pc) + `" fill-opacity="` + num(pop) + `"/>`)
|
||
}
|
||
|
||
svgMods := []vdom.Mod{
|
||
vdom.WithRef(c.svgRef),
|
||
vdom.Attr("viewBox", usViewBox),
|
||
vdom.Attr("role", "img"),
|
||
vdom.Raw(b.String()),
|
||
}
|
||
if p.Height > 0 {
|
||
svgMods = append(svgMods, vdom.Attr("class", "block"), vdom.Attr("style", "height:"+num(p.Height)+"px;width:auto;margin:0 auto"))
|
||
} else {
|
||
svgMods = append(svgMods, vdom.Attr("class", "block w-full"), vdom.Attr("style", "aspect-ratio:960/600"))
|
||
}
|
||
if !p.NoTooltip {
|
||
svgMods = append(svgMods,
|
||
vdom.OnEvent(vdom.EVENT_POINTERMOVE, c.onMove),
|
||
vdom.On(vdom.EVENT_POINTERLEAVE, c.onLeave),
|
||
)
|
||
}
|
||
|
||
children := []*vdom.VNode{vdom.Svg(svgMods...), c.tooltipNode(p, hv, mn, mx, steps)}
|
||
if hasData {
|
||
children = append(children, choroplethLegend(mn, mx, steps, c.valFmt))
|
||
}
|
||
return vdom.Div(kids([]vdom.Mod{vdom.Attr("class", cx("relative w-full", p.Class))}, children)...)
|
||
}
|
||
|
||
func choroplethLegend(mn, mx float64, steps int, fmt func(float64) string) *vdom.VNode {
|
||
swatches := []*vdom.VNode{}
|
||
for k := 1; k <= steps; k++ {
|
||
swatches = append(swatches, vdom.Span(vdom.Attr("class", "h-3 w-6"),
|
||
vdom.Attr("style", "background-color:var(--color-choropleth-"+strconv.Itoa(k)+")")))
|
||
}
|
||
ramp := vdom.Div(kids([]vdom.Mod{vdom.Attr("class", "flex overflow-hidden rounded-xs")}, swatches)...)
|
||
return vdom.Div(vdom.Attr("class", "mt-3 flex items-center gap-2 text-ss text-ink-muted"),
|
||
vdom.Span(vdom.Attr("style", "font-variant-numeric:tabular-nums"), vdom.Text(fmt(mn))),
|
||
ramp,
|
||
vdom.Span(vdom.Attr("style", "font-variant-numeric:tabular-nums"), vdom.Text(fmt(mx))),
|
||
)
|
||
}
|