// 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;
let svg;
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 edgePoint({ 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);
}
class Point {
constructor(x = 0, y = 0) {
this.x = +x;
this.y = +y;
}
toString() {
return `${this.x},${this.y}`;
}
}
function position(e, firingArc, firingArcOutline, aimLine, grid) {
// TODO: handle exactly horizontal and vertical lines?
let pointer = new DOMPoint(e.clientX, e.clientY);
let pointerPt = pointer.matrixTransform(grid.getScreenCTM().inverse());
let pivotPt = new Point(aimLine.getAttribute('x1'), aimLine.getAttribute('y1'));
let { x, y, width, height } = grid.getBBox();
const bounds = {
x: [x, x + width],
y: [y, y + height]
}
let cornerPoints = [
[x, y],
[x + width, y],
[x + width, y + height],
[x, y + height]
].map(([x, y]) => new Point(x, y));
let aimPt = edgePoint(pivotPt, pointerPt, bounds);
aimLine.setAttributeNS(null, 'x2', aimPt.x);
aimLine.setAttributeNS(null, 'y2', aimPt.y);
let angle = calculateAngle(aimPt.x - pivotPt.x, aimPt.y - pivotPt.y);
let arcAngle = arcSize[firingArc.dataset.size];
let distance = Math.sqrt((aimPt.x - pivotPt.x) ** 2 + (aimPt.y - pivotPt.y) ** 2);
let yDelta = distance * Math.cos(angle) * Math.tan(arcAngle);
let xDelta = distance * Math.sin(angle) * Math.tan(arcAngle);
let arcPt1 = new Point(aimPt.x - xDelta, aimPt.y - yDelta);
let arcPt2 = new Point(aimPt.x + xDelta, aimPt.y + yDelta);
arcPt1 = edgePoint(pivotPt, arcPt1, bounds);
arcPt2 = edgePoint(pivotPt, arcPt2, bounds);
firingArcOutline.setAttributeNS(null, 'points', `${arcPt1} ${pivotPt} ${arcPt2}`);
function touchSameEdge({ x: x1, y: y1 }, { x: x2, y: y2 }) {
return x1 === x2 || y1 === y2;
}
function touchOrthogonalEdges({ x: x1, y: y1 }, { x: x2, y: y2 }) {
return (bounds.x.includes(x1) && bounds.y.includes(y2)) || (bounds.y.includes(y1) && bounds.x.includes(x2));
}
function shareValue({ x: x1, y: y1 }, { x: x2, y: y2 }) {
return x1 === x2 || y1 === y2;
}
// 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 findWhichCorners(pt, ...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 ? 'x' : 'y';
let cornerVal;
if (pt[nonSharedValKey] < sharedValPt[nonSharedValKey]) {
cornerVal = Math.min(...bounds[nonSharedValKey]);
} else {
cornerVal = Math.max(...bounds[nonSharedValKey]);
}
return cornerPoints.filter(cp => cp[nonSharedValKey] === cornerVal);
}
let points;
if (touchSameEdge(arcPt1, arcPt2)) {
// 0-corner case
points = [arcPt2, pivotPt, arcPt1];
} else if (touchOrthogonalEdges(arcPt1, arcPt2)) {
if (touchSameEdge(aimPt, arcPt1) || touchSameEdge(aimPt, arcPt2)) {
// 1-corner case
let cp = cornerPoints.find(cp => shareValue(cp, arcPt1) && shareValue(cp, arcPt2));
points = [arcPt2, pivotPt, arcPt1, cp];
} else {
// 3-corner case
points = cornerPoints.filter(cp => !shareValue(cp, arcPt1) || !shareValue(cp, arcPt2));
let index = points.findIndex(cp => shareValue(cp, arcPt2));
points.splice(index + 1, 0, arcPt2, pivotPt, arcPt1);
}
} else {
if (touchSameEdge(aimPt, arcPt1) || touchSameEdge(aimPt, arcPt2)) {
// 2-corner case, aim and an arc point touch the same edge
points = findWhichCorners(aimPt, arcPt1, arcPt2);
let index = points.findIndex(cp => shareValue(cp, arcPt2));
points.splice(index + 1, 0, arcPt2, pivotPt, arcPt1);
} else {
// 2-corner case, aim and both arc points all touch different edges
points = cornerPoints.filter(cp => shareValue(cp, aimPt) || shareValue(cp, aimPt));
let index = points.findIndex(cp => shareValue(cp, arcPt2));
points.splice(index + 1, 0, arcPt2, pivotPt, arcPt1);
}
}
firingArc.setAttributeNS(null, 'points', points.join(' '));
}
function setDataAttrs({ dataset: { allegiance, number }}, el) {
el.dataset.allegiance = allegiance;
el.dataset.number = number;
}
function getClipPathId({ dataset: { allegiance, number }}) {
return `clip-path-${allegiance}-${number}`;
}
function getUnclipped() {
return svg.querySelectorAll('#firing-arcs :not([clip-path])');
};
export default function (el) {
svg = el;
this.set = function (size, counter, { x, y }) {
this.get(counter).forEach(fa => fa.remove());
let arcLayer = svg.querySelector('#shapes');
let outlineLayer = svg.querySelector('#lines');
let arcContainer = svg.querySelector('#firing-arcs');
let grid = svg.querySelector('.grid');
let aimLine = document.createElementNS(svgns, 'line');
aimLine.setAttributeNS(null, 'x1', x);
aimLine.setAttributeNS(null, 'y1', y);
aimLine.setAttributeNS(null, 'x2', x);
aimLine.setAttributeNS(null, 'y2', y);
outlineLayer.appendChild(aimLine);
let firingArc = document.createElementNS(svgns, 'polygon');
setDataAttrs(counter, firingArc);
firingArc.setAttributeNS(null, 'points', `${x},${y}`);
firingArc.dataset.size = size;
firingArc.classList.add('firing-arc', 'active');
let firingArcOutline = document.createElementNS(svgns, 'polyline');
setDataAttrs(counter, firingArcOutline);
firingArcOutline.setAttributeNS(null, 'points', `${x},${y}`);
let clipShape = document.createElementNS(svgns, 'circle');
clipShape.setAttributeNS(null, 'cx', x);
clipShape.setAttributeNS(null, 'cy', y);
clipShape.setAttributeNS(null, 'r', clippedFiringArcRadius);
let clipPath = document.createElementNS(svgns, 'clipPath');
setDataAttrs(counter, clipPath);
clipPath.setAttributeNS(null, 'id', getClipPathId(counter));
clipPath.appendChild(clipShape);
arcContainer.appendChild(clipPath);
arcLayer.appendChild(firingArc);
outlineLayer.appendChild(firingArcOutline);
// const positionListener = position.bind(svg, firingArc, firingArcOutline, aim, grid);
function positionListener(e) {
position(e, firingArc, firingArcOutline, aimLine, grid);
}
let placementListener = e => {
grid.removeAttribute('style');
aimLine.remove();
svg.querySelectorAll('.firing-arc.active').forEach(el => el.classList.remove('active'));
svg.removeEventListener('mousemove', positionListener);
};
let cancelPlacementListener = e => {
e.preventDefault();
this.get(counter).forEach(fa => fa.remove());
grid.removeAttribute('style');
svg.removeEventListener('mousemove', positionListener);
};
grid.style.pointerEvents = 'none';
firingArc.addEventListener('click', placementListener, { once: true });
firingArc.addEventListener('contextmenu', cancelPlacementListener, { once: true });
svg.addEventListener('mousemove', positionListener);
};
this.clear = function (allegiance) {
const selector = `#firing-arcs [data-allegiance="${allegiance}"]`;
svg.querySelectorAll(selector).forEach(el => el.remove());
};
this.get = function ({ dataset: { allegiance, number }}) {
return svg.querySelectorAll(`#firing-arcs [data-number="${number}"][data-allegiance="${allegiance}"], #firing-arcs line`);
};
this.toggleVisibility = function (allegiance) {
const vis = firingArcVisibility[allegiance],
clipPaths = svg.querySelectorAll(`clipPath[data-allegiance="${allegiance}"]`);
clipPaths.forEach(cp => cp.style.display = !vis ? 'none' : '');
firingArcVisibility[allegiance] = !vis;
};
this.toggleCounterVisibility = function ({ dataset: { number, allegiance }}, vis) {
const cp = svg.querySelector(`#clip-path-${allegiance}-${number}`),
display = vis ? 'none' : '';
if (cp) {
cp.style.display = firingArcVisibility[allegiance] ? 'none' : display;
}
};
this.clipAll = function () {
let unclipped = getUnclipped();
unclipped.forEach(el => {
const { number, allegiance } = el.dataset,
clipPathId = `clip-path-${allegiance}-${number}`,
isVisible = firingArcVisibility[allegiance];
if (isVisible) {
svg.querySelector(`#${clipPathId}`).style.display = 'none';
}
el.setAttributeNS(null, 'clip-path', `url(#${clipPathId})`);
});
};
}