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6x 6x 6x 6x 6x 6x 123x 123x 123x 6x 6x 6x 6x 6x 6x 6x 6x 6x 6x 6x 6x 6x 1x 1x | import {GeomElement} from "./elements/GeomElement";
import {PlaneElement} from "./elements/plane/PlaneElement";
import {FixedPoint} from "./elements/point/FixedPoint";
import {AllConstructions, Construction, SortedParams, constructions, getConstructionName} from "./elements/Constructions";
import {PointElement} from "./elements/point/PointElement";
import {Canvas} from "canvas";
import {LineElement} from "./elements/line/LineElement";
import {PolygonElement} from "./elements/polygon/PolygonElement";
import {CircleElement} from "./elements/circle/CircleElement";
import {ISlide, ISlideAnimation, IAnimationConfig} from "./index";
import {SlateAnimator} from "./SlateAnimator";
import {DiagnosticLog, IDiagnostic, IDiagnosticInput, DiagnosticSeverity,
diagnosticEventDetail} from "./Diagnostics";
export type SlateCanvas = HTMLCanvasElement | Canvas;
export type ResolveJustification = (ref: string) => string | null | undefined;
// #140 — an element that is highlighted or mid-animation is what the viewer
// is meant to be looking at, so it should not be painted over by whatever
// happens to be declared after it in the deck's `elements` array.
//
// `emphasized` is `_emphasisAmount > 0`, so this stays true through the
// post-animation fade taper — an element can't drop back down in z-order
// while it is still visibly gold. `drawProgress < 1` is the independent
// "currently being drawn in" flag: it defaults to 1 and every animation's
// finalise()/cancel resets it to 1, so it covers an animation that drives
// partial geometry without touching emphasis.
export function isPromoted(e: GeomElement): boolean {
return e.shouldHighlight || e.emphasized || e.drawProgress < 1;
}
/**
* Reorder one draw pass so promoted elements paint last (on top), while
* both groups keep their existing relative order.
*
* The promotion is deliberately *within a pass*, not to the top of the whole
* figure: `drawElements` runs face → edge → vertex → name, so a promoted
* face still stays under every edge. Highlighting a filled polygon therefore
* can't hide the lines drawn across it.
*
* When nothing is promoted this returns the input order, so the render is
* bit-for-bit unchanged for every static figure and every snapshot golden.
*/
export function promotedDrawOrder(elements: GeomElement[]): GeomElement[] {
let promoted: GeomElement[] | null = null;
for (let e of elements) {
if (isPromoted(e)) {
if (promoted == null) promoted = [];
promoted.push(e);
}
}
// Nothing highlighted or animating — the overwhelmingly common case.
// Hand back the original array untouched (no allocation, no reorder).
if (promoted == null) return elements;
const rest: GeomElement[] = [];
for (let e of elements) if (!isPromoted(e)) rest.push(e);
return rest.concat(promoted);
}
export class Slate {
protected _elements : GeomElement[];
// Name aliases — secondary names that resolve to existing elements
// without adding new ones to _elements. The original Geometry Applet
// and Euclid's *Elements* refer to the same circle by every
// permutation of its three named points (BCD ≡ CDB ≡ DBC ≡ …) and
// to lines by either endpoint order (AB ≡ BA). Authors register
// those equivalences here so the prose-side `{NAME}` shortcode can
// light up the canonical element without needing a parallel
// invisible duplicate per alias.
private _aliases : Map<string, string> = new Map();
// #140 — draw highlighted / mid-animation elements last within each
// pass so they aren't painted over by later-declared neighbours.
// On by default; set false to keep the strict declaration order.
private _highlightOnTop : boolean = true;
// Optional slideshow walk-through; populated from init().slides.
// Empty array means no presentation mode is available; SlateControls
// skips the "▶ Present" button.
private _slides : ISlide[] = [];
// Consumer-supplied callback resolving a justification ref label
// (e.g. "I.Post.3") to a URL. Returns null/undefined when the ref
// isn't recognised, in which case the Presentation overlay renders
// the ref as plain text. Undefined means no resolver was passed.
private _resolveJustification : ResolveJustification | null = null;
// Slide-transition animation config (rates, durations, modifiers).
// The slate ships a default; init() merges in whatever the
// consumer provides via IInitialization.animationConfig.
private _animationConfig : IAnimationConfig = {};
// The frame-driver. Lazy-created on first animateTo() so a
// headless test slate that never animates doesn't allocate a
// requestAnimationFrame loop.
private _animator : SlateAnimator | null = null;
// Ephemeral helper elements an animation can spawn for its
// lifetime (compass arms, guide circles, straightedge bars).
// Drawn on top of _elements in the same face → edge → vertex →
// name order; never appear in lookupElement; cleared on
// animator.cancel() as a safety net.
private _ephemerals : GeomElement[] = [];
// View transform: model (logical) coords → display px is
// F·model + T, where F = _viewScale (uniform) and T = (_viewOffsetX,
// _viewOffsetY). drawElements then scales by dpr to the bitmap; the
// pick path inverts it. T centres the figure when maximized (#99/#107);
// F shrinks the figure to fit a narrow display (#71). Defaults
// F=1, T=(0,0) are a no-op, so every existing render path — and the
// headless snapshot path — is bit-for-bit unchanged.
// #138 — the bounding box the maximized / presentation centring was
// computed from. Captured ONCE on entering the maximized view (#114
// centres once, not per slide) and cleared on leaving, so the centre
// can't drift as slides reveal and hide elements, and so cloneAside's
// centre phase (#99) eases to exactly the same target.
private _centringBounds : { minX: number, maxX: number, minY: number, maxY: number } | null = null;
private _viewOffsetX : number = 0;
private _viewOffsetY : number = 0;
private _viewScale : number = 1;
// The construction's authored coordinate extent (logical px). Element
// coords live here. Defaults to the canvas bitmap so the headless /
// snapshot path has logical == display == bitmap (fit-scale 1). init()
// overrides it with the authored size on a real DOM canvas (#71).
private _logicalWidth : number = 0;
private _logicalHeight : number = 0;
// Last-dispatched highlighted-name key, so the geomlib:highlight event
// (#108) fires only when the SET of highlighted elements changes — not
// on every redraw frame / emphasisAmount fade.
private _lastHighlightedKey : string = "\u0000";
// #154 — what this slate has complained about, so a badge can show it
// and a consumer can read it. Per-slate on purpose: the dedupe flags
// this replaced were module-global, so one figure's warning silenced
// every other figure on the page.
private _diagnostics : DiagnosticLog = new DiagnosticLog();
private _diagnosticListeners : Array<(s: Slate) => void> = [];
protected _screen : PlaneElement;
protected _pick : PointElement;
protected _canvas : SlateCanvas;
private _htmlCanvas : HTMLCanvasElement = null;
protected _bgcolor : string;
public inTest : boolean = false;
private static numSlate : number = 0;
private _itsNumSlate : number = -1;
constructor(canvas: SlateCanvas) {
Slate.numSlate += 1;
this._itsNumSlate = Slate.numSlate;
this._elements = [];
if(canvas == null) {
throw new TypeError("canvas cannot be null or undefined.");
}
this._canvas = canvas;
let screen_origin = new FixedPoint({x:0,y:0,z:0});
screen_origin.name = "screen_origin";
let screen_x = new FixedPoint({x:1,y:0,z:0});
screen_x.name = "screen_x";
let screen_y = new FixedPoint({x:0,y:1,z:0});
screen_y.name = "screen_y";
let screen = new PlaneElement({
A: screen_origin,
B: screen_x,
C: screen_y
});
screen.name = "screen";
screen.nameColor = null;
screen.isScreen = true;
this._screen = screen;
this._pick = null;
for(let e of [screen_origin, screen_x, screen_y, screen]) {
e.nameColor = null;
e.vertexColor = null;
e.vertexHighlightColor = null;
e.faceColor = null;
e.faceHighlightColor = null;
this._elements.push(e);
}
let slate = this;
let cnv : HTMLCanvasElement = this._canvas as HTMLCanvasElement;
this._htmlCanvas = cnv;
if(this._htmlCanvas.addEventListener == null) return;
// Pointer Events unify mouse / touch / stylus into one event model.
// Setting touch-action: none here (rather than relying on
// consumer-side CSS) tells the browser not to claim drag gestures
// for scroll/zoom; calling setPointerCapture on pointerdown ensures
// we keep getting move/up events even when the finger leaves the
// canvas bounds. See issue #55 for the design rationale.
this._htmlCanvas.style.touchAction = "none";
// Only the primary pointer drives the drag pipeline for now.
// Multi-touch (two-finger rotation etc.) is intentionally not yet
// wired — design questions tracked in issue #57.
let activePointerId: number | null = null;
this._htmlCanvas.addEventListener("pointerdown", (ev: PointerEvent) => {
if (activePointerId !== null) return; // already tracking a primary
activePointerId = ev.pointerId;
try { slate._htmlCanvas.setPointerCapture(ev.pointerId); } catch (_) { /* ignore */ }
let [x, y] = slate._getCanvasPosition(ev.clientX, ev.clientY);
slate._onMouseDown(x, y);
});
this._htmlCanvas.addEventListener("pointermove", (ev: PointerEvent) => {
if (ev.pointerId !== activePointerId) return;
let [x, y] = slate._getCanvasPosition(ev.clientX, ev.clientY);
slate._onMouseDrag(x, y);
});
let endPointer = (ev: PointerEvent) => {
if (ev.pointerId !== activePointerId) return;
let [x, y] = slate._getCanvasPosition(ev.clientX, ev.clientY);
slate._onMouseUp(x, y);
try { slate._htmlCanvas.releasePointerCapture(ev.pointerId); } catch (_) { /* ignore */ }
activePointerId = null;
};
this._htmlCanvas.addEventListener("pointerup", endPointer);
this._htmlCanvas.addEventListener("pointercancel", endPointer);
this._htmlCanvas.addEventListener("lostpointercapture", (ev: PointerEvent) => {
if (ev.pointerId === activePointerId) {
// Browser revoked capture (e.g., system gesture); clear pick state.
if (slate._pick != null) {
slate._pick = null;
}
activePointerId = null;
}
});
}
_getCanvasPosition(x: number, y: number) : [number, number] {
let r = this._htmlCanvas.getBoundingClientRect();
// Map display px → model (logical) coords: invert the view
// transform F·model + T, so a click lands on the real element even
// while the figure is fit-scaled (#71) or slid to centre (#99/#107).
// getBoundingClientRect is display px; dpr never enters here.
// F = 1, T = 0 → today's plain rect subtraction.
const F = this._viewScale || 1;
return [(x - r.left - this._viewOffsetX) / F,
(y - r.top - this._viewOffsetY) / F];
}
_onMouseDown(x: number, y: number) {
this._pick = null;
this.movePick(x, y);
};
_onMouseUp(x: number, y: number) {
if (this._pick == null) return;
this.movePick(x, y);
this._pick = null;
};
_onMouseDrag(x: number, y: number) {
if (this._pick == null) return;
this.movePick(x, y);
};
get elements() : GeomElement[] {
return this._elements;
}
set highlightOnTop(value: boolean) {
this._highlightOnTop = value;
}
get highlightOnTop() : boolean {
return this._highlightOnTop;
}
set bgcolor(value: string ) {
this._bgcolor = value;
}
get bgcolor() : string {
return this._bgcolor;
}
// Public accessor for the underlying canvas. Consumer-side code on
// multi-canvas pages (e.g. the {NAME} shortcode on euclids-elements.org)
// needs to compare DOM positions of each slate's canvas against the
// prose-side <span> to pick the right slate. Was protected before
// 0.4.0; the few prior callers (s.canvas in elem-ref-highlight.js)
// were just reading undefined and falling through to a brute-force
// walk of geomlib.slates.
get canvas() : SlateCanvas {
return this._canvas;
}
lookupElement(name: string) : GeomElement {
for (let elem of this._elements) {
if (elem.name == name) {
return elem;
}
}
// Direct miss — follow the alias map and look up the canonical
// name. One hop only: we don't chase chains because aliases are
// expected to point at real element names, not at each other.
let canonical = this._aliases.get(name);
if (canonical != null) {
for (let elem of this._elements) {
if (elem.name == canonical) return elem;
}
}
return null;
}
// Register a single secondary name → canonical name mapping. Idempotent.
// Called by init() when the user passes an `aliases` field.
addAlias(from: string, to: string) : void {
this._aliases.set(from, to);
}
addAliases(aliases: {[from: string]: string}) : void {
for (let from in aliases) this._aliases.set(from, aliases[from]);
}
// Draggable elements named here are excluded from the slideshow's
// every-slide auto-union and follow slide visible sets like any
// other element — for proof-introduced draggables ("Take an
// arbitrary point F") that shouldn't show before their moment.
// They stay fully draggable whenever visible (#89). Populated by
// init() from the `deferDraggables` field.
private _deferredDraggables : Set<string> = new Set();
get deferredDraggables() : Set<string> {
return this._deferredDraggables;
}
deferDraggables(names: string[]) : void {
for (const n of names || []) this._deferredDraggables.add(n);
}
get slides() : ISlide[] {
return this._slides;
}
set slides(value: ISlide[]) {
this._slides = value || [];
}
get resolveJustification() : ResolveJustification | null {
return this._resolveJustification;
}
set resolveJustification(value: ResolveJustification | null) {
this._resolveJustification = value;
}
get animationConfig() : IAnimationConfig {
return this._animationConfig;
}
set animationConfig(value: IAnimationConfig) {
this._animationConfig = value || {};
}
get animator() : SlateAnimator | null {
return this._animator;
}
get ephemerals() : GeomElement[] {
return this._ephemerals;
}
addEphemeral(e: GeomElement) : void {
this._ephemerals.push(e);
}
// Register a pre-built element as a persistent (non-ephemeral) member of
// the figure — drawn in the normal pass, addressable by name, and governed
// by the slideshow visible-set. Used by macro animations (e.g.
// A.Circle.compassTransfer's keepCircles) to leave named scaffolding that a
// later slide can re-show, where addEphemeral's wipe-on-advance won't do.
addElement(e: GeomElement) : void {
if (this._elements.indexOf(e) === -1) this._elements.push(e);
}
removeEphemeral(e: GeomElement) : void {
const i = this._ephemerals.indexOf(e);
if (i >= 0) this._ephemerals.splice(i, 1);
}
clearEphemerals() : void {
this._ephemerals.length = 0;
}
get viewOffsetX() : number { return this._viewOffsetX; }
get viewOffsetY() : number { return this._viewOffsetY; }
get viewScale() : number { return this._viewScale; }
// Device pixel ratio (#71). The canvas BITMAP is sized to display px ×
// dpr so drawing lands on native device pixels (crisp on HiDPI/retina).
// Headless / no window → 1, so node-canvas rendering (and the snapshot
// goldens) is unchanged.
private _dpr() : number {
return (typeof window !== "undefined" && window.devicePixelRatio) || 1;
}
// The authored coordinate extent (logical px) — the space element
// coords live in. Falls back to the bitmap when unset (headless /
// snapshot path), so logical == bitmap there. (#71)
get logicalWidth() : number { return this._logicalWidth || this._canvas.width; }
get logicalHeight() : number { return this._logicalHeight || this._canvas.height; }
setLogicalSize(w: number, h: number) : void {
if (w > 0) this._logicalWidth = w;
if (h > 0) this._logicalHeight = h;
}
// The canvas DISPLAY size in CSS px (responsive; clientWidth on a real
// DOM canvas, the fixed bitmap headless). The figure is fit-scaled from
// logical → display. (#71)
get displayWidth() : number {
const c = this._canvas as any;
return (typeof c.clientWidth === "number" && c.clientWidth) || this._canvas.width;
}
get displayHeight() : number {
const c = this._canvas as any;
return (typeof c.clientHeight === "number" && c.clientHeight) || this._canvas.height;
}
// Recompute the fit-scale F = min(1, display / logical): shrink the
// figure to fit a narrow display, never grow it. Called on init/resize.
recomputeFitScale() : void {
const sx = this.displayWidth / this.logicalWidth;
const sy = this.displayHeight / this.logicalHeight;
this._viewScale = Math.min(1, sx, sy);
}
// Set the view transform's translate T (display px). drawElements
// applies F·model + T; the pick path inverts it. (#99/#107)
setViewOffset(x: number, y: number) : void {
this._viewOffsetX = x;
this._viewOffsetY = y;
}
clearViewOffset() : void {
this._viewOffsetX = 0;
this._viewOffsetY = 0;
}
// Axis-aligned bounding box (canvas px) of the visible figure —
// every named, visible, non-screen element. Returns null when the
// figure is empty. Used by cloneAside auto-place for the centre
// target and the fit check (#99). Points/lines/polygons/circles are
// measured exactly; sector markers sit inside their vertex (already
// counted) so they're not separately walked.
visibleBounds() : { minX: number, maxX: number, minY: number, maxY: number } | null {
return this._bounds(true);
}
// Like visibleBounds() but over EVERY named, non-screen element
// regardless of its `visible` flag — a stable bound that doesn't drift
// as a presentation reveals/hides elements slide-to-slide. Used to
// centre the figure in a maximized / presentation view (#107).
figureBounds() : { minX: number, maxX: number, minY: number, maxY: number } | null {
return this._bounds(false);
}
// #138 — does this element put any ink on the canvas?
//
// Deck figures carry construction helpers that exist only to define a
// direction or a slider's track — a "point at infinity" aim, the two
// anchors a lineSlider runs between — authored with zero colours so they
// draw nothing. They are still `visible`, so a visibility filter does NOT
// exclude them; only asking what actually paints does.
//
// The test is per type because a colour slot an element never uses tells
// us nothing: PointElement.drawEdge / drawFace are no-ops, so a point's
// edgeColor (which defaults to black when the author omits the field)
// must not count as ink — that default is exactly what made these helpers
// look paintable.
private _paintsInk(elem: GeomElement) : boolean {
if (!elem.visible) return false;
if (elem.nameColor != null) return true;
if (elem instanceof PointElement) return elem.vertexColor != null;
return elem.edgeColor != null || elem.faceColor != null;
}
// Bounding box to centre the figure on in the maximized / presentation
// view (#107). Measures only elements that actually paint, so an
// off-screen zero-colour helper can't inflate the box and translate the
// real geometry off-canvas — the #138 blank-slideshow bug, hit on I.35,
// I.42 and I.43.
//
// Captured once per maximized session rather than recomputed: the result
// must not move as slides change visibility, and cloneAside reads the
// same captured box so its centre phase lands where the base centring
// already is. Falls back to the all-elements bounds if nothing paints at
// all (a figure built entirely from helpers), so the caller always gets
// the same shape of answer as before.
captureCentringBounds() : { minX: number, maxX: number, minY: number, maxY: number } | null {
const inked = this._bounds(false, (e) => this._paintsInk(e));
this._centringBounds = inked != null ? inked : this._bounds(false);
return this._centringBounds;
}
get centringBounds() : { minX: number, maxX: number, minY: number, maxY: number } | null {
return this._centringBounds;
}
clearCentringBounds() : void {
this._centringBounds = null;
}
private _bounds(visibleOnly: boolean,
accept?: (e: GeomElement) => boolean) : { minX: number, maxX: number, minY: number, maxY: number } | null {
let minX = Infinity, maxX = -Infinity, minY = Infinity, maxY = -Infinity;
const add = (x: number, y: number) => {
if (x < minX) minX = x; if (x > maxX) maxX = x;
if (y < minY) minY = y; if (y > maxY) maxY = y;
};
for (let elem of this._elements) {
if (elem.name == null || elem.name.startsWith("screen")) continue;
if (visibleOnly && !elem.visible) continue;
if (accept != null && !accept(elem)) continue;
if (elem instanceof PolygonElement) {
for (let v of elem.V) add(v.x, v.y);
} else if (elem instanceof CircleElement) {
const r = elem.radius;
add(elem.Center.x - r, elem.Center.y - r);
add(elem.Center.x + r, elem.Center.y + r);
} else if (elem instanceof LineElement) {
add(elem.A.x, elem.A.y);
add(elem.B.x, elem.B.y);
} else if (elem instanceof PointElement) {
add(elem.x, elem.y);
}
}
if (minX === Infinity) return null;
return { minX, maxX, minY, maxY };
}
// All names that resolve to the element named `canonical`: the
// element's own name plus every alias whose target is it. Used to tag
// the geomlib:highlight event so a consumer can match a prose ref by
// any spelling (BCD ≡ CDB ≡ DBC). (#108)
namesFor(canonical: string) : string[] {
const names = [canonical];
this._aliases.forEach((target, from) => {
if (target === canonical && from !== canonical) names.push(from);
});
return names;
}
// Lazy-create the animator on first use. Each slate owns at most
// one — cancel() preserves it for re-use across slide transitions.
private _ensureAnimator() : SlateAnimator {
if (this._animator == null) {
this._animator = new SlateAnimator(this);
}
return this._animator;
}
// Public entry point for slideshow controllers. Diff the current
// visibility / highlight state against the target, run any slide-
// listed animations against the elements becoming visible. Newly-
// visible elements without an explicit animation entry pop in
// instantly (4b parity). Returns a Promise that resolves when the
// animator completes the run or cancel() is called.
animateTo(
targetVisible: Set<string>,
targetHighlighted: Set<string>,
slideAnimations: ISlideAnimation[],
mode: "cascade" | "parallel",
) : Promise<void> {
return this._ensureAnimator().run(
targetVisible, targetHighlighted, slideAnimations, mode,
);
}
// Hide every named element whose name is not in the supplied set.
// Names not matching any element are silently ignored; elements
// without a name (intermediate construction outputs) are left alone.
// Screen-helper elements (screen / screen_origin / screen_x /
// screen_y) follow the same rule: their visible flag does flip, but
// since they're created with all-null colours they never draw
// visible pixels anyway. Called by the presentation overlay per
// slide; consumers can call directly too.
setVisibleNames(names: string[]) : void {
const visible = new Set(names);
for (let elem of this._elements) {
if (elem.name == null) continue;
elem.visible = visible.has(elem.name);
}
}
// Names of elements that start hidden (angle markers by default, or
// anything in init's `initiallyHidden`). clearVisibility restores to
// this baseline rather than blanket-true, so hidden elements stay
// hidden after a presentation walk. (#100)
private _initiallyHidden : Set<string> = new Set();
get initiallyHidden() : Set<string> {
return this._initiallyHidden;
}
// Mark a named element hidden in the initial figure: flips its
// visible flag off now and remembers it for clearVisibility.
setInitiallyHidden(name: string) : void {
if (name == null) return;
this._initiallyHidden.add(name);
const elem = this.lookupElement(name);
if (elem != null) elem.visible = false;
}
// Restore every element's visible flag to its initial baseline —
// true, except names registered as initially hidden. Counterpart to
// setVisibleNames; called on presentation exit so the canvas
// returns to its inline default.
clearVisibility() : void {
for (let elem of this._elements) {
elem.visible = !(elem.name != null && this._initiallyHidden.has(elem.name));
}
}
// Sort params into P[] (points), E[] (other elements), N[] (integers),
// matching Java's selectDataChoice (Slate.java lines 344-393).
// LineElements are expanded into their two endpoint PointElements, unless
// the target construction opts out (keepLineElements — e.g. curvedTriangle/
// curvedPolygon take a line intact as a straight-side carrier).
convertParams(params: any[], keepLineElements: boolean = false) : SortedParams {
let P: PointElement[] = [];
let E: GeomElement[] = [];
let N: number[] = [];
for(let param of params) {
switch(typeof(param)) {
case "string":
let g : GeomElement = this.lookupElement(param);
if ( g == null )
throw new TypeError(`Element with name ${param} not found.`);
if (g instanceof PointElement) {
P.push(g);
} else if (g instanceof LineElement && !keepLineElements) {
// LineElement expands to two PointElements (matching Java)
P.push(g.A);
P.push(g.B);
} else {
E.push(g);
}
break;
case "number":
N.push(param);
break;
default:
throw new TypeError("Expecting only named elements (strings) or numbers.");
}
}
return {P, E, N};
}
findConstruction(cm : AllConstructions, sp: SortedParams) : Construction {
for(let c of constructions) {
if(c.validateSignature(cm, sp)) {
return c;
}
}
return null;
}
createElement(cm : AllConstructions, params: any[], name?: string) : GeomElement {
// A construction for this method may want LineElement params kept
// intact (not expanded to endpoints) — see Construction.keepsLineElements.
let keepLines = constructions.some(c => c.constructionMethod === cm && c.keepsLineElements);
let sp : SortedParams = this.convertParams(params, keepLines);
let c : Construction = this.findConstruction(cm, sp);
if(c == null) {
let cName : String = getConstructionName(cm);
if (name == null) {
name = "";
}
throw new TypeError(`Construction not found for "${name}" ${cName} with params P=[${sp.P}] E=[${sp.E}] N=[${sp.N}]`);
}
let [gs, g] = c.construct(this._screen, sp.P, sp.E, sp.N);
// Mark as preexisting if this element was already in _elements
// before this construction (e.g., point;first returns an existing
// PointElement). Preexisting elements are skipped during
// rotate/translate to avoid double-movement.
// (Java: Slate.java preexists[] array)
if (this._elements.indexOf(g) !== -1) {
g.preexists = true;
}
if(name != null)
g.name = name;
for (let elem of gs) {
if (this._elements.indexOf(elem) == -1)
this._elements.push(elem);
}
if(this._elements.indexOf(g) == -1)
this._elements.push(g);
return g;
}
reset() : void {
for (let element of this._elements) {
element.reset();
}
this.update();
}
update() : void {
for(let element of this._elements) element.update();
this.drawElements();
}
drawElements(): void {
if(this.inTest) return;
let ctx : CanvasRenderingContext2D = this._canvas.getContext("2d") as CanvasRenderingContext2D;
// View transform (#71/#99/#107): model (logical) coords map to
// device px as dpr·(F·model + T), where F = _viewScale (fit) and
// T = view offset (centre). Clear + background fill cover the whole
// bitmap under identity; the figure + ephemerals then draw under the
// model→device transform. Headless dpr=1, F=1, T=0 → identity, so
// node-canvas rendering (and every snapshot golden) is unchanged.
const dpr = this._dpr(), F = this._viewScale;
const tx = this._viewOffsetX, ty = this._viewOffsetY;
// Keep decorations (labels, dots, line widths) a constant on-screen
// size while the geometry is fit-scaled by F (#71). 1/F ≥ 1; F=1 → 1.
GeomElement.styleScale = F > 0 ? 1 / F : 1;
ctx.setTransform(1, 0, 0, 1, 0, 0);
ctx.clearRect(0, 0, this._canvas.width, this._canvas.height);
ctx.fillStyle = this._bgcolor;
ctx.fillRect(0, 0, this._canvas.width, this._canvas.height);
ctx.setTransform(dpr * F, 0, 0, dpr * F, dpr * tx, dpr * ty);
// #140 — highlighted / mid-animation elements paint last within each
// pass, so a later-declared neighbour can't chop the gold stroke
// where it crosses. Identity when nothing is promoted.
const order = this._highlightOnTop
? promotedDrawOrder(this._elements) : this._elements;
for(let element of order) element.drawFace(this._canvas);
for(let element of order) element.drawEdge(this._canvas);
for(let element of order) element.drawVertex(this._canvas);
// and then draw their names.
for(let element of order)
element.drawName(this._canvas);
// Ephemeral animation helpers render on top of the permanent
// figure (compass arms, guide circles, straightedge bars).
// Same face → edge → vertex → name pass order so a guide arc
// overlays correctly without re-clearing the canvas.
for(let e of this._ephemerals) e.drawFace(this._canvas);
for(let e of this._ephemerals) e.drawEdge(this._canvas);
for(let e of this._ephemerals) e.drawVertex(this._canvas);
for(let e of this._ephemerals) e.drawName(this._canvas);
ctx.setTransform(1, 0, 0, 1, 0, 0); // reset so nothing leaks
GeomElement.styleScale = 1;
this._dispatchHighlightChange();
}
// #108 — bidirectional highlight binding. After each real draw, if the
// SET of highlighted elements (shouldHighlight || emphasized — the
// boolean intent, ignoring the fading emphasisAmount) has changed,
// emit a `geomlib:highlight` CustomEvent on the canvas so a consuming
// page can light up every textual reference to those elements. The
// event carries each element's canonical name + all its aliases. Fires
// on any highlight source (prose-ref hover, slide `highlighted`) since
// it lives in the shared redraw path; idempotent (no re-emit on an
// unchanged set → no feedback loop). No-op when the canvas can't
// dispatch DOM events (node-canvas in tests).
private _dispatchHighlightChange() : void {
const names: string[] = [];
for (let elem of this._elements) {
if (elem.name == null || elem.name.startsWith("screen")) continue;
if (elem.shouldHighlight || elem.emphasized) names.push(elem.name);
}
const key = names.sort().join("|");
if (key === this._lastHighlightedKey) return;
this._lastHighlightedKey = key;
const canvas: any = this._canvas;
if (!canvas || typeof canvas.dispatchEvent !== "function"
|| typeof CustomEvent !== "function") return;
const highlighted = names.map(n => ({ name: n, aliases: this.namesFor(n) }));
canvas.dispatchEvent(new CustomEvent("geomlib:highlight", {
bubbles: true,
detail: { highlighted },
}));
}
// ---- Diagnostics (#154) ------------------------------------------
//
// geomlib skips what it cannot resolve and keeps rendering, which is
// the right behaviour — a deck with one bad name should still draw.
// The cost is that the only evidence was a console line nobody has
// open. Reporting through here records it too, so SlateControls can
// badge the canvas and a consumer can read the list.
/**
* Record a diagnostic and mirror it to the console.
*
* Deduped per key, per slate: repeat reports bump a counter without
* a second console line. That replaces two module-global dedupe
* flags which silenced a warning for every OTHER figure on the page
* once any one figure tripped them.
*/
reportDiagnostic(input: IDiagnosticInput) : void {
const rec = this._diagnostics.report(input, Date.now());
if (rec == null) return; // already reported on this slate
if (typeof console !== "undefined") {
const fn = rec.severity === "error" ? console.error : console.warn;
if (fn) fn("[geomlib] " + rec.message);
}
this._dispatchDiagnostic(rec);
this._notifyDiagnosticListeners();
}
/** Everything this slate has reported, oldest first. */
get diagnostics() : IDiagnostic[] {
return this._diagnostics.entries;
}
/** Worst severity reported, or null when the slate is clean. */
get diagnosticSeverity() : DiagnosticSeverity | null {
return this._diagnostics.severity;
}
/**
* Forget everything reported so far.
*
* NOT called from reset(): minimize() and presentation-exit both run
* reset() internally, and construction-time diagnostics never fire
* again, so clearing there would silently discard exactly the
* warnings worth keeping. SlateControls calls this from the explicit
* reset control / `r` key instead — a deliberate viewer gesture.
*/
clearDiagnostics() : void {
this._diagnostics.clear();
this._dispatchDiagnostic(null);
this._notifyDiagnosticListeners();
}
/** Subscribe to diagnostic changes. Returns an unsubscribe fn. */
onDiagnosticsChanged(listener: (s: Slate) => void) : () => void {
this._diagnosticListeners.push(listener);
return () => {
const i = this._diagnosticListeners.indexOf(listener);
if (i >= 0) this._diagnosticListeners.splice(i, 1);
};
}
private _notifyDiagnosticListeners() : void {
for (const l of this._diagnosticListeners.slice()) {
try { l(this); } catch (_) { /* a listener must not break reporting */ }
}
}
// Same capability guard as the geomlib:highlight dispatch above — a
// node-canvas Canvas has no dispatchEvent, so the headless path
// short-circuits here exactly as it does for highlights.
private _dispatchDiagnostic(d: IDiagnostic | null) : void {
const canvas: any = this._canvas;
if (!canvas || typeof canvas.dispatchEvent !== "function"
|| typeof CustomEvent !== "function") return;
canvas.dispatchEvent(new CustomEvent("geomlib:diagnostic", {
bubbles: true,
detail: diagnosticEventDetail(this._diagnostics, d),
}));
}
// Update coordinates starting with element[i+1], matching Java's
// Slate.java updateCoordinates (lines 808-814). Only elements AFTER
// the picked element are recomputed — elements before it are left
// untouched to avoid reprojection artifacts after rotation.
updateCoordinates(i : number) {
for(++i; i < this._elements.length; i++) {
if(!this._elements[i].defined())
this._elements[i].reset();
this._elements[i].update();
}
this.drawElements();
}
translateCoordinates(dx : number, dy: number) {
// translate all non-preexisting elements
// (Java: Slate.java line 819 — if (!preexists[i]) element[i].translate(...))
for(let i = 0; i < this._elements.length; i++) {
let elem = this._elements[i];
if (!elem.preexists)
elem.translate(dx, dy);
}
this.update();
}
closestVisiblePoint(elements : GeomElement[], p : PointElement, tolerance : number = 30) : PointElement {
// Use 2D screen distance (x,y only, ignoring z) for picking,
// matching the Java applet's movePick() at Slate.java:887-889.
// The canvas is a 2D projection; a 3D point at (x,y,z) renders
// at screen position (x,y) regardless of z.
let screenDist2 = (a: PointElement, b: PointElement) =>
(a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y);
let sortedDistanceElements = elements
.filter(e => e instanceof PointElement)
.map(e => e as PointElement)
.filter(e => e.vertexColor != null)
.sort((a,b) => {
let adcp = screenDist2(a, p);
let bdcp = screenDist2(b, p);
if(adcp < bdcp) {
return -1;
} else if (bdcp < adcp) {
return 1;
}
return 0;
});
if (sortedDistanceElements.length == 0) return null;
let bestDistPoint = sortedDistanceElements[0];
if(Math.sqrt(screenDist2(bestDistPoint, p)) > tolerance) return null;
return bestDistPoint;
}
private _getPick(c: number, d: number) : PointElement {
if (this._pick != null) return this._pick;
let currentPoint = new PointElement({x:c,y:d});
let closestVisiblePoint = this.closestVisiblePoint(this._elements, currentPoint);
if(closestVisiblePoint == null) return;
this._pick = closestVisiblePoint;
return this._pick;
}
// Set the pivot point for scene rotation.
// Format: "pointName" or "pointName,planeName"
// Without a plane, the pivot is set on the screen plane.
// With a plane, the pivot is set on that plane (for 3D rotation).
// (Java: Slate.java setPivot, lines 787-801)
setPivot(param : string) : void {
let parts = param.split(",");
let pointName = parts[0].trim();
let e : GeomElement = this.lookupElement(pointName);
if (e == null || !(e instanceof PointElement)) return;
let piv : PointElement = e as PointElement;
if (parts.length > 1) {
// "A,xyplane" — set pivot on a specific plane
let planeName = parts[1].trim();
let p : GeomElement = this.lookupElement(planeName);
if (p == null || !(p instanceof PlaneElement)) return;
(p as PlaneElement).pivot = piv;
} else {
// "A" — set pivot on screen plane
piv._AP = this._screen;
this._screen.pivot = piv;
}
}
movePick(c: number, d: number) : void {
if(this._getPick(c, d) == null) return;
let picki = this._elements.indexOf(this._pick);
// Clamp the drag to the on-screen region in MODEL coords. Under the
// view transform F·model + T, the display spans model
// [−T/F, (display − T)/F] — so the fit-scale (#71) and centre offset
// (#99/#107) both shift/scale the bounds. F=1, T=0 → [0, display].
const F = this._viewScale || 1;
let ox = this._viewOffsetX, oy = this._viewOffsetY;
let loX = -ox / F, hiX = (this.displayWidth - ox) / F;
if (c < loX) c = loX; else if (c > hiX) c = hiX;
let loY = -oy / F, hiY = (this.displayHeight - oy) / F;
if (d < loY) d = loY; else if (d > hiY) d = hiY;
if (Math.abs(c - this._pick.x) + Math.abs(d - this._pick.y) < 1.0) {
return; // no motion
}
if ( this._pick.draggable ) {
if(this._pick.drag(c,d)) {
this.updateCoordinates(picki);
} else {
return;
}
} else if (this._pick.AP != null
&& this._pick.AP.pivot != null
&& this._pick.AP.pivot != this._pick) { // rotate around the pivot
this.rotateCoordinates(c,d);
} else {
let dx = c - this._pick.x;
let dy = d - this._pick.y;
this.translateCoordinates(dx,dy);
}
this.drawElements();
}
rotateCoordinates(c : number, d : number) : void {
// rotate space according to how pick goes around pivot in the plane
let pick : PointElement = this._pick;
let piv : PointElement = pick.AP.pivot;
// compute old and new pick's 3D coordinates relative to the pivot
let oldP : PointElement = PointElement.difference(pick,piv);
let newx : number = c-piv.x;
let newy : number = d-piv.y; //(newz is irrelevant)
// find their 2D coordinates on the plane
let S : PointElement = pick.AP.S;
let T : PointElement = pick.AP.T;
let olds : number = PointElement.dot(oldP,S);
let oldt : number = PointElement.dot(oldP,T);
let den : number = S.x * T.y - S.y * T.x;
let news : number = (newx*T.y - newy*T.x)/den;
let newt : number = (newy*S.x - newx*S.y)/den;
// compute the scale&rotation factors
den = olds*olds + oldt*oldt;
let ac : number = (news*olds + newt*oldt)/den;
let as : number = (newt*olds - news*oldt)/den;
// Rotate all non-preexisting elements directly.
// (Java: Slate.java line 843-845)
for (let elem of this._elements) {
if (!elem.preexists)
elem.rotate(piv, ac, as);
}
// After direct rotation, recompute derived elements from their (now
// rotated) parents. Java doesn't need this because element[] carries
// duplicate entries for shared objects — a Layoff created by
// line;extend and re-referenced by point;last appears at two indices,
// one with preexists=false that gets rotated directly. TS dedupes
// _elements, so a shared object marked preexists=true is skipped,
// which means Layoff-style points backed by bare LineElement wrappers
// would never get moved directly (bare LineElement.rotate is a no-op).
// Running update() rebuilds them from their (rotated) parents, which
// produces the same result because rotation is a linear operation
// and Layoff.update() derives its position from parent coords.
this.update();
}
}
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