// 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 horzToVertDistRatio = 2 * Math.sqrt(3) / 3,
arcSize = {
'small': Math.atan(horzToVertDistRatio / 6),
'medium': Math.atan(horzToVertDistRatio / 2),
'large': Math.atan(7 * horzToVertDistRatio / 2)
},
firingArcVisibility = {
defender: false,
attacker: 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 };