Web Dev Solutions

Catalin Mititiuc

// source: https://www.redblobgames.com/grids/hexagons/ // Horizontal distance between hex centers is sqrt(3) * size. The vertical // distance is 3 / 2 * size. When we calculate horzDist / vertDist, the size // cancels out, leaving us with a unitless ratio of sqrt(3) / (3 / 2), or // 2 * sqrt(3) / 3. const svgns = "http://www.w3.org/2000/svg", horzToVertDistRatio = 2 * Math.sqrt(3) / 3, arcSize = { 'small': Math.atan(horzToVertDistRatio / 6), 'medium': Math.atan(horzToVertDistRatio / 2), 'large': Math.atan(7 * horzToVertDistRatio / 2) }, firingArcVisibility = { davion: false, liao: false }, clippedFiringArcRadius = 25; class Point { constructor(x = 0, y = 0) { this.x = +x; this.y = +y; } toString() { return `${this.x},${this.y}`; } } function calculateAngle(xDiff, yDiff) { yDiff = -yDiff; let angle = Math.abs(Math.atan(yDiff / xDiff)); if (xDiff < 0 && yDiff > 0) { angle = Math.PI - angle; } else if (xDiff < 0 && yDiff < 0) { angle = Math.PI + angle; } else if (xDiff > 0 && yDiff < 0) { angle = 2 * Math.PI - angle; } return angle; } function calcEdgePt({ x: x1, y: y1 }, { x: x2, y: y2 }, { x: [minX, maxX], y: [minY, maxY] }) { const xDiff = x2 - x1, yDiff = y2 - y1, xIntercept = y => (y - y1) * xDiff / yDiff + x1, yIntercept = x => (x - x1) * yDiff / xDiff + y1; let pointCoords; if (xDiff > 0 && yDiff > 0) { let x = xIntercept(maxY); pointCoords = x <= maxX ? [x, maxY] : [maxX, yIntercept(maxX)]; } else if (xDiff > 0 && yDiff < 0) { let y = yIntercept(maxX); pointCoords = y >= minY ? [maxX, y] : [xIntercept(minY), minY]; } else if (xDiff < 0 && yDiff < 0) { let x = xIntercept(minY); pointCoords = x >= minX ? [x, minY] : [minX, yIntercept(minX)]; } else { let y = yIntercept(minX); pointCoords = y <= maxY ? [minX, y] : [xIntercept(maxY), maxY]; } return new Point(...pointCoords); } function touchSameEdge({ x: x1, y: y1 }, { x: x2, y: y2 }) { return x1 === x2 || y1 === y2; } function shareValue({ x: x1, y: y1 }, { x: x2, y: y2 }) { return x1 === x2 || y1 === y2; } function touchOrthogonalEdges({ x: x1, y: y1 }, { x: x2, y: y2 }, bounds) { return (bounds.x.includes(x1) && bounds.y.includes(y2)) || (bounds.y.includes(y1) && bounds.x.includes(x2)); } function getCornerPts({ x: [xMin, xMax], y: [yMin, yMax] }) { const corners = [[xMin, yMin], [xMax, yMin], [xMax, yMax], [xMin, yMax]]; return corners.map(([x, y]) => new Point(x, y)); } function getBounds({ x, y, width, height }) { return { x: [x, x + width], y: [y, y + height] }; } // which arcpt does aimpt share a value with? // if they share an x value, we will look for corner y value // if they share a y value, we will look for corner x value // is aim pt non-shared value greater or less than arcpt non-shared value? function findWhichTwoCorners(pt, bounds, ...pts) { const ptVals = Object.values(pt), sharedValPt = pts.find(({ x, y }) => ptVals.includes(x) || ptVals.includes(y)); if (!sharedValPt) { return; } const nonSharedValKey = pt.x === sharedValPt.x ? 'y' : 'x'; let cornerVal; if (pt[nonSharedValKey] < sharedValPt[nonSharedValKey]) { cornerVal = Math.min(...bounds[nonSharedValKey]); } else { cornerVal = Math.max(...bounds[nonSharedValKey]); } return getCornerPts(bounds).filter(cp => cp[nonSharedValKey] === cornerVal); } function selectCornerPoints(aimPt, arcPt1, arcPt2, bounds) { const cornerPts = getCornerPts(bounds); let points; if (touchSameEdge(arcPt1, arcPt2)) { // 0-corner case points = []; } else if (touchOrthogonalEdges(arcPt1, arcPt2, bounds)) { if (touchSameEdge(aimPt, arcPt1) || touchSameEdge(aimPt, arcPt2)) { // 1-corner case let cp = cornerPts.find(cp => shareValue(cp, arcPt1) && shareValue(cp, arcPt2)); points = [cp]; } else { // 3-corner case points = cornerPts.filter(cp => !shareValue(cp, arcPt1) || !shareValue(cp, arcPt2)); } } else { if (touchSameEdge(aimPt, arcPt1) || touchSameEdge(aimPt, arcPt2)) { // 2-corner case, aim and an arc point touch the same edge points = findWhichTwoCorners(aimPt, bounds, arcPt1, arcPt2); } else { // 2-corner case, aim and both arc points all touch different edges points = cornerPts.filter(cp => shareValue(cp, aimPt) || shareValue(cp, aimPt)); } } return points; } function orderPoints(arcPoints, cornerPts) { if (cornerPts.length === 0) { return arcPoints; } const index = cornerPts.findIndex(cp => shareValue(cp, arcPoints.at(0))); return cornerPts.slice(0, index + 1).concat(arcPoints).concat(cornerPts.slice(index + 1)); } function calcArcLinePtDeltas(aimPt, pivotPt, size) { const angle = calculateAngle(aimPt.x - pivotPt.x, aimPt.y - pivotPt.y), arcAngle = arcSize[size], distance = Math.sqrt((aimPt.x - pivotPt.x) ** 2 + (aimPt.y - pivotPt.y) ** 2), yDelta = distance * Math.cos(angle) * Math.tan(arcAngle), xDelta = distance * Math.sin(angle) * Math.tan(arcAngle); return { xDelta, yDelta }; } function calcPoints(e, aimLine, grid, size) { const pointer = new DOMPoint(e.clientX, e.clientY), pointerPt = pointer.matrixTransform(grid.getScreenCTM().inverse()), pivotPt = new Point(aimLine.getAttribute('x1'), aimLine.getAttribute('y1')), bounds = getBounds(grid.getBBox()), aimPt = calcEdgePt(pivotPt, pointerPt, bounds), { xDelta, yDelta } = calcArcLinePtDeltas(aimPt, pivotPt, size), arcPt1 = calcEdgePt(pivotPt, new Point(aimPt.x - xDelta, aimPt.y - yDelta), bounds), arcPt2 = calcEdgePt(pivotPt, new Point(aimPt.x + xDelta, aimPt.y + yDelta), bounds), outlinePoints = [arcPt2, pivotPt, arcPt1], cornerPoints = selectCornerPoints(aimPt, arcPt1, arcPt2, bounds), arcPoints = orderPoints(outlinePoints, cornerPoints); return { aimPt, outlinePoints, arcPoints }; } function setDataAttrs({ dataset: { allegiance, number }}, el) { el.dataset.allegiance = allegiance; el.dataset.number = number; } function getClipPathId({ dataset: { allegiance, number }}) { return `clip-path-${allegiance}-${number}`; } function getUnclipped(svg) { return svg.querySelectorAll('#firing-arcs #shapes polygon:not([clip-path]), #firing-arcs #lines polyline:not([clip-path])'); }; function createAimLine(x, y, container) { const aimLine = document.createElementNS(svgns, 'line'); aimLine.setAttributeNS(null, 'x1', x); aimLine.setAttributeNS(null, 'y1', y); aimLine.setAttributeNS(null, 'x2', x); aimLine.setAttributeNS(null, 'y2', y); container.appendChild(aimLine); return aimLine; } function createClipPath(x, y, id, container) { const clipShape = document.createElementNS(svgns, 'circle'), clipPath = document.createElementNS(svgns, 'clipPath'); clipShape.setAttributeNS(null, 'cx', x); clipShape.setAttributeNS(null, 'cy', y); clipShape.setAttributeNS(null, 'r', clippedFiringArcRadius); clipPath.setAttributeNS(null, 'id', id); clipPath.appendChild(clipShape); container.appendChild(clipPath); return clipPath; } function createFiringArc(x, y, size, container) { const firingArc = document.createElementNS(svgns, 'polygon'); firingArc.setAttributeNS(null, 'points', `${x},${y}`); firingArc.dataset.size = size; firingArc.classList.add('firing-arc', 'active'); container.appendChild(firingArc); return firingArc; } function createFiringArcOutline(x, y, container) { const firingArcOutline = document.createElementNS(svgns, 'polyline'); firingArcOutline.setAttributeNS(null, 'points', `${x},${y}`); container.appendChild(firingArcOutline); return firingArcOutline; } function queryContainers(svg) { const grid = svg.querySelector('.grid'), arcContainer = svg.querySelector('#firing-arcs'), arcLayer = arcContainer.querySelector('#shapes'), outlineLayer = arcContainer.querySelector('#lines'); return { grid, containers: { arcContainer, arcLayer, outlineLayer }}; } function create(x, y, size, counter, { arcContainer, arcLayer, outlineLayer }) { const aimLine = createAimLine(x, y, outlineLayer), firingArc = createFiringArc(x, y, size, arcLayer), firingArcOutline = createFiringArcOutline(x, y, outlineLayer), clipPath = createClipPath(x, y, getClipPathId(counter), arcContainer); setDataAttrs(counter, firingArc); setDataAttrs(counter, firingArcOutline); setDataAttrs(counter, clipPath); return { aimLine, firingArc, firingArcOutline }; } function set(svg, size, counter, { x, y }) { get(svg, counter).forEach(el => el.remove()); const { grid, containers } = queryContainers(svg), { aimLine, firingArc, firingArcOutline } = create(x, y, size, counter, containers); function positionListener(e) { const { aimPt, outlinePoints, arcPoints } = calcPoints(e, aimLine, grid, size); aimLine.setAttributeNS(null, 'x2', aimPt.x); aimLine.setAttributeNS(null, 'y2', aimPt.y); firingArcOutline.setAttributeNS(null, 'points', outlinePoints.join(' ')); firingArc.setAttributeNS(null, 'points', arcPoints.join(' ')); } function placementListener() { aimLine.remove(); firingArc.classList.remove('active'); grid.removeAttribute('style'); svg.removeEventListener('mousemove', positionListener); } function cancelPlacementListener(e) { e.preventDefault(); get(counter).forEach(el => el.remove()); grid.removeAttribute('style'); svg.removeEventListener('mousemove', positionListener); } grid.style.pointerEvents = 'none'; firingArc.addEventListener('click', placementListener, { once: true }); firingArc.addEventListener('contextmenu', cancelPlacementListener, { once: true }); svg.addEventListener('mousemove', positionListener); } function clear(svg, allegiance) { const selector = `#firing-arcs [data-allegiance="${allegiance}"]`; svg.querySelectorAll(selector).forEach(el => el.remove()); } function get(svg, { dataset: { allegiance, number }}) { return svg.querySelectorAll(`#firing-arcs [data-number="${number}"][data-allegiance="${allegiance}"], #firing-arcs line`); } function toggleVisibility(svg, allegiance) { const vis = firingArcVisibility[allegiance], clipPaths = svg.querySelectorAll(`clipPath[data-allegiance="${allegiance}"]`); clipPaths.forEach(cp => cp.style.display = !vis ? 'none' : ''); firingArcVisibility[allegiance] = !vis; } function toggleCounterVisibility(svg, { dataset: { number, allegiance }}, vis) { const cp = svg.querySelector(`#clip-path-${allegiance}-${number}`), display = vis ? 'none' : ''; if (cp) { cp.style.display = firingArcVisibility[allegiance] ? 'none' : display; } } function clipAll(svg) { getUnclipped(svg).forEach(el => { const { number, allegiance } = el.dataset, clipPathId = `clip-path-${allegiance}-${number}`, isVisible = firingArcVisibility[allegiance]; if (isVisible) { svg.querySelector(`#${clipPathId}`).style.display = 'none'; } el.setAttributeNS(null, 'clip-path', `url(#${clipPathId})`); }); } export { set, clear, get, toggleVisibility, toggleCounterVisibility, clipAll };