@jbrowse/plugin-wiggle/esm/drawLine.js

JBrowse 2 wiggle adapters, tracks, etc.

import { readConfObject } from '@jbrowse/core/configuration';
import { clamp } from '@jbrowse/core/util';
import { checkStopToken2, createStopTokenChecker, } from '@jbrowse/core/util/stopToken';
import { WIGGLE_CLIP_HEIGHT, WIGGLE_FUDGE_FACTOR, getScale } from "./util.js";
export function drawLine(ctx, props) {
    const { features, regions, bpPerPx, scaleOpts, height: unadjustedHeight, ticks: { values }, displayCrossHatches, colorCallback, config, offset = 0, staticColor, stopToken, lastCheck = createStopTokenChecker(stopToken), } = props;
    const region = regions[0];
    const regionStart = region.start;
    const regionEnd = region.end;
    const reversed = region.reversed;
    const invBpPerPx = 1 / bpPerPx;
    const width = (regionEnd - regionStart) * invBpPerPx;
    const height = unadjustedHeight - offset * 2;
    const clipColor = readConfObject(config, 'clipColor');
    const scale = getScale({ ...scaleOpts, range: [0, height] });
    const domain = scale.domain();
    const niceMin = domain[0];
    const niceMax = domain[1];
    const domainSpan = niceMax - niceMin;
    const isLog = scaleOpts.scaleType === 'log';
    const linearRatio = domainSpan !== 0 ? height / domainSpan : 0;
    const log2 = Math.log(2);
    const logMin = Math.log(niceMin) / log2;
    const logMax = Math.log(niceMax) / log2;
    const logSpan = logMax - logMin;
    const logRatio = logSpan !== 0 ? height / logSpan : 0;
    const toY = isLog
        ? (n) => clamp(height - (Math.log(n) / log2 - logMin) * logRatio, 0, height) +
            offset
        : (n) => clamp(height - (n - niceMin) * linearRatio, 0, height) + offset;
    let lastVal;
    let prevLeftPx = Number.NEGATIVE_INFINITY;
    const reducedFeatures = [];
    if (staticColor) {
        ctx.beginPath();
        ctx.strokeStyle = staticColor;
        const clippingFeatures = [];
        for (const feature of features.values()) {
            checkStopToken2(lastCheck);
            const fStart = feature.get('start');
            const fEnd = feature.get('end');
            const leftPx = reversed
                ? (regionEnd - fEnd) * invBpPerPx
                : (fStart - regionStart) * invBpPerPx;
            const rightPx = reversed
                ? (regionEnd - fStart) * invBpPerPx
                : (fEnd - regionStart) * invBpPerPx;
            if ((leftPx | 0) !== (prevLeftPx | 0) || rightPx - leftPx > 1) {
                reducedFeatures.push(feature);
                prevLeftPx = leftPx;
            }
            const score = feature.get('score');
            const scoreY = toY(score);
            if (score > niceMax) {
                clippingFeatures.push({
                    leftPx,
                    w: rightPx - leftPx + WIGGLE_FUDGE_FACTOR,
                    high: true,
                });
            }
            else if (score < niceMin && !isLog) {
                clippingFeatures.push({
                    leftPx,
                    w: rightPx - leftPx + WIGGLE_FUDGE_FACTOR,
                    high: false,
                });
            }
            const startY = lastVal !== undefined ? toY(lastVal) : scoreY;
            if (!reversed) {
                ctx.moveTo(leftPx, startY);
                ctx.lineTo(leftPx, scoreY);
                ctx.lineTo(rightPx, scoreY);
            }
            else {
                ctx.moveTo(rightPx, startY);
                ctx.lineTo(rightPx, scoreY);
                ctx.lineTo(leftPx, scoreY);
            }
            lastVal = score;
        }
        ctx.stroke();
        if (clippingFeatures.length > 0) {
            ctx.fillStyle = clipColor;
            for (const { leftPx, w, high } of clippingFeatures) {
                if (high) {
                    ctx.fillRect(leftPx, offset, w, WIGGLE_CLIP_HEIGHT);
                }
                else {
                    ctx.fillRect(leftPx, height - WIGGLE_CLIP_HEIGHT, w, WIGGLE_CLIP_HEIGHT);
                }
            }
        }
    }
    else {
        for (const feature of features.values()) {
            checkStopToken2(lastCheck);
            const fStart = feature.get('start');
            const fEnd = feature.get('end');
            const leftPx = reversed
                ? (regionEnd - fEnd) * invBpPerPx
                : (fStart - regionStart) * invBpPerPx;
            const rightPx = reversed
                ? (regionEnd - fStart) * invBpPerPx
                : (fEnd - regionStart) * invBpPerPx;
            if ((leftPx | 0) !== (prevLeftPx | 0) || rightPx - leftPx > 1) {
                reducedFeatures.push(feature);
                prevLeftPx = leftPx;
            }
            const score = feature.get('score');
            const scoreY = toY(score);
            const w = rightPx - leftPx + WIGGLE_FUDGE_FACTOR;
            const c = colorCallback(feature, score);
            ctx.beginPath();
            ctx.strokeStyle = c;
            const startY = lastVal !== undefined ? toY(lastVal) : scoreY;
            if (!reversed) {
                ctx.moveTo(leftPx, startY);
                ctx.lineTo(leftPx, scoreY);
                ctx.lineTo(rightPx, scoreY);
            }
            else {
                ctx.moveTo(rightPx, startY);
                ctx.lineTo(rightPx, scoreY);
                ctx.lineTo(leftPx, scoreY);
            }
            ctx.stroke();
            lastVal = score;
            if (score > niceMax) {
                ctx.fillStyle = clipColor;
                ctx.fillRect(leftPx, offset, w, WIGGLE_CLIP_HEIGHT);
            }
            else if (score < niceMin && !isLog) {
                ctx.fillStyle = clipColor;
                ctx.fillRect(leftPx, height - WIGGLE_CLIP_HEIGHT, w, WIGGLE_CLIP_HEIGHT);
            }
        }
    }
    if (displayCrossHatches) {
        ctx.lineWidth = 1;
        ctx.strokeStyle = 'rgba(200,200,200,0.5)';
        for (const tick of values) {
            ctx.beginPath();
            ctx.moveTo(0, Math.round(toY(tick)));
            ctx.lineTo(width, Math.round(toY(tick)));
            ctx.stroke();
        }
    }
    return {
        reducedFeatures,
    };
}