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| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 | /** * useSuperpositionInteraction — Pointer event handler for the interactive * superposition (triangle drag/flip/snap) proof step. * * Follows the useDragGivenPoints pattern: standalone hook registering * capture-phase pointer events on the canvas. Calls stopPropagation() * during active phases to block tool interaction and pan/zoom. */ import { useEffect } from 'react' import type { MutableRefObject, RefObject } from 'react' import type { ConstructionState, EuclidViewportState, SuperpositionPhase, Vec2 } from '../types' import { getPoint } from '../engine/constructionState' import { screenToWorld2D, worldToScreen2D } from '../../shared/coordinateConversions' import { triangleCentroid, circumradius, triangleOrientation, computeAutoRotation, rotateVerticesAround, pointInTriangle, } from '../engine/superpositionMath' export interface UseSuperpositionOptions { canvasRef: RefObject<HTMLCanvasElement | null> constructionRef: MutableRefObject<ConstructionState> viewportRef: MutableRefObject<EuclidViewportState> superpositionPhaseRef: MutableRefObject<SuperpositionPhase> needsDrawRef: MutableRefObject<boolean> isMobileRef: MutableRefObject<boolean> } /** Snap zone: centroid distance < this fraction of circumradius */ const SNAP_THRESHOLD = 0.5 export function useSuperpositionInteraction({ canvasRef, constructionRef, viewportRef, superpositionPhaseRef, needsDrawRef, isMobileRef, }: UseSuperpositionOptions): void { useEffect(() => { const canvas = canvasRef.current if (!canvas) return /** Track whether the user has an active pointer down (required before processing moves) */ let activePointerId: number | null = null function getCSSSize() { const dpr = window.devicePixelRatio || 1 return { w: canvas!.width / dpr, h: canvas!.height / dpr } } function toWorld(sx: number, sy: number): Vec2 { const v = viewportRef.current const { w, h } = getCSSSize() const pt = screenToWorld2D( sx, sy, v.center.x, v.center.y, v.pixelsPerUnit, v.pixelsPerUnit, w, h ) return pt } function toScreen(wx: number, wy: number): Vec2 { const v = viewportRef.current const { w, h } = getCSSSize() return worldToScreen2D(wx, wy, v.center.x, v.center.y, v.pixelsPerUnit, v.pixelsPerUnit, w, h) } /** Get world-space positions of a triangle's vertices from construction state */ function getTriVertices(ids: [string, string, string]): [Vec2, Vec2, Vec2] | null { const state = constructionRef.current const pts = ids.map((id) => getPoint(state, id)) if (pts.some((p) => !p)) return null return pts.map((p) => ({ x: p!.x, y: p!.y })) as [Vec2, Vec2, Vec2] } function handlePointerDown(e: PointerEvent) { const phase = superpositionPhaseRef.current if (phase.tag === 'idle' || phase.tag === 'settled' || phase.tag === 'lifting') return const rect = canvas!.getBoundingClientRect() const sx = e.clientX - rect.left const sy = e.clientY - rect.top if (phase.tag === 'dragging') { // Start/continue drag — record anchor and capture pointer e.stopPropagation() e.preventDefault() activePointerId = e.pointerId const worldPos = toWorld(sx, sy) superpositionPhaseRef.current = { ...phase, dragAnchor: worldPos, } } else if (phase.tag === 'mismatched') { // Tap on cutout → flip e.stopPropagation() e.preventDefault() // Hit-test tap in screen coords const cutoutScreen = phase.cutoutVertices.map((v) => toScreen(v.x, v.y)) as [ Vec2, Vec2, Vec2, ] const tapPoint: Vec2 = { x: sx, y: sy } if (pointInTriangle(tapPoint, cutoutScreen[0], cutoutScreen[1], cutoutScreen[2])) { // Compute flip axis from the first two mapped vertex pairs const tgtVerts = getTriVertices(phase.tgtTriIds) if (tgtVerts) { // Axis: line connecting first two target vertices (after mapping) const axisPoint = tgtVerts[0] const axLen = Math.hypot(tgtVerts[1].x - tgtVerts[0].x, tgtVerts[1].y - tgtVerts[0].y) const axisDir: Vec2 = axLen > 1e-10 ? { x: (tgtVerts[1].x - tgtVerts[0].x) / axLen, y: (tgtVerts[1].y - tgtVerts[0].y) / axLen, } : { x: 1, y: 0 } superpositionPhaseRef.current = { tag: 'flipping', startTime: performance.now(), axisPoint, axisDir, preFlipVertices: phase.cutoutVertices, postFlipVertices: tgtVerts, srcTriIds: phase.srcTriIds, tgtTriIds: phase.tgtTriIds, mapping: phase.mapping, } needsDrawRef.current = true } } } } function handlePointerMove(e: PointerEvent) { const phase = superpositionPhaseRef.current if (phase.tag !== 'dragging') return // Only process moves when user has an active pointer down if (activePointerId === null || e.pointerId !== activePointerId) return e.stopPropagation() e.preventDefault() const rect = canvas!.getBoundingClientRect() const sx = e.clientX - rect.left const sy = e.clientY - rect.top const worldPos = toWorld(sx, sy) // Translate cutout by pointer delta from initial centroid + anchor offset const dx = worldPos.x - phase.dragAnchor.x const dy = worldPos.y - phase.dragAnchor.y let newVerts = phase.cutoutVertices.map((v) => ({ x: v.x + dx, y: v.y + dy, })) as [Vec2, Vec2, Vec2] // Get target triangle vertices const tgtVerts = getTriVertices(phase.tgtTriIds) if (tgtVerts) { const cutCentroid = triangleCentroid(newVerts[0], newVerts[1], newVerts[2]) const tgtCentroid = triangleCentroid(tgtVerts[0], tgtVerts[1], tgtVerts[2]) const circumR = circumradius(tgtVerts[0], tgtVerts[1], tgtVerts[2]) // Auto-rotation const autoAngle = computeAutoRotation(cutCentroid, tgtCentroid, newVerts, tgtVerts, circumR) if (Math.abs(autoAngle) > 1e-6) { newVerts = rotateVerticesAround(newVerts, cutCentroid, autoAngle) } // Check snap zone const dist = Math.hypot(cutCentroid.x - tgtCentroid.x, cutCentroid.y - tgtCentroid.y) if (dist < SNAP_THRESHOLD * circumR) { // Orientation check const cutOrientation = triangleOrientation(newVerts[0], newVerts[1], newVerts[2]) const tgtOrientation = triangleOrientation(tgtVerts[0], tgtVerts[1], tgtVerts[2]) if (cutOrientation === tgtOrientation) { // Same orientation → snap superpositionPhaseRef.current = { tag: 'snapping', startTime: performance.now(), fromVertices: newVerts, toVertices: tgtVerts, srcTriIds: phase.srcTriIds, tgtTriIds: phase.tgtTriIds, mapping: phase.mapping, } } else { // Opposite orientation → mismatch superpositionPhaseRef.current = { tag: 'mismatched', cutoutVertices: newVerts, srcTriIds: phase.srcTriIds, tgtTriIds: phase.tgtTriIds, mapping: phase.mapping, settleTime: performance.now(), } } needsDrawRef.current = true return } } // Update dragging phase with new vertices and anchor superpositionPhaseRef.current = { ...phase, cutoutVertices: newVerts, dragAnchor: worldPos, } needsDrawRef.current = true } function handlePointerUp(e: PointerEvent) { const phase = superpositionPhaseRef.current if (phase.tag === 'dragging') { // Release — cutout stays where it is e.stopPropagation() if (e.pointerId === activePointerId) { activePointerId = null } } } // Block all pointer events during active superposition phases function handleCapture(e: PointerEvent) { const phase = superpositionPhaseRef.current if ( phase.tag === 'lifting' || phase.tag === 'flipping' || phase.tag === 'snapping' || phase.tag === 'settled' ) { e.stopPropagation() e.preventDefault() } } canvas.addEventListener('pointerdown', handlePointerDown, { capture: true }) canvas.addEventListener('pointermove', handlePointerMove, { capture: true }) canvas.addEventListener('pointerup', handlePointerUp, { capture: true }) canvas.addEventListener('pointerdown', handleCapture, { capture: true }) return () => { canvas.removeEventListener('pointerdown', handlePointerDown, { capture: true }) canvas.removeEventListener('pointermove', handlePointerMove, { capture: true }) canvas.removeEventListener('pointerup', handlePointerUp, { capture: true }) canvas.removeEventListener('pointerdown', handleCapture, { capture: true }) } }, [canvasRef, constructionRef, viewportRef, superpositionPhaseRef, needsDrawRef, isMobileRef]) } |