Lasso Fill

lassofill.js

Gfx.lassoFill = function(o, f, e, g) {
    var m = function(D, H, w) {
        var p = H[0];
        var B = H[1];
        var F = D * 4 + w;
        var q = p[F + 0];
        var v = p[F + 1];
        var A = p[F + 2];
        var G = ((q == f.r) && (v == f.g) && (A == f.b));
        var q = B[F + 0];
        var v = B[F + 1];
        var A = B[F + 2];
        var C = B[F + 3];
        var u = ((q === 0) && (v === 0) && (A === 255) && (C === 255));
        return ((u) && (G))
    };
    var h = function(q, v, A) {
        var w = v[0];
        var u = v[1];
        var p = q * 4 + A;
        u[p + 0] = 0;
        u[p + 1] = 0;
        u[p + 2] = 255;
        u[p + 3] = 0
    };
    var n = function(G, H, F, w) {
        var C = null;
        var u;
        var D = F.nextp;
        while ((D !== null) && (D.nextp !== null)) {
            C = D.nextp;
            var q = Math.round(D.xIntersect);
            var p = Math.round(C.xIntersect);
            var B = H + w.y;
            var A = d.getScanline(B);
            var v = d.scanlineDataArr;
            Gfx.floodFill(new Vector2(q, B), w, d, m, h, {
                computeBbox: false
            });
            Gfx.floodFill(new Vector2(p, B), w, d, m, h, {
                computeBbox: false
            });
            D = C.nextp
        }
    };
    g.fillStyle = "rgba(0,0,255,0.0)";
    g.globalCompositeOperation = "copy";
    g.fillRect(0, 0, g.canvas.width, g.canvas.height);
    g.fillStyle = "rgba(0,0,255,1.0)";
    g.globalCompositeOperation = "source-over";
    var k = Gfx.scanFill(g, o);
    var d = Gfx.scanlineCacheFull;
    d.init([e, g], k);
    Gfx.scanFill(g, o, k, n);
    d.flush();
    return new Rect()
};
Gfx.scanFill = function(d, m, k, h) {
    var g = [];
    if (typeof k === "undefined") {
        k = Rect.createEnclosingRect(m);
        k.w += 1;
        k.h += 1
    } else {
        var e = Rect.createEnclosingRect(m);
        e.w += 1;
        e.h += 1
    }
    if (typeof h === "undefined") {
        h = Gfx.fillScan
    }
    for (var f = 0; f <= k.h; f++) {
        g.push({
            nextp: null
        })
    }
    Gfx.makeSET(m, g, k);
    AET = {
        nextp: null
    };
    for (var f = 0; f <= k.h; f++) {
        Gfx.buildAET(f, AET, g, k);
        if (AET.nextp !== null) {
            h(d, f, AET, k);
            Gfx.updateAET(f, AET, k);
            Gfx.resortAET(AET)
        }
    }
    return k
};
Gfx.insertEdge = function(d, h) {
    var f = d;
    var g = d.nextp;
    while (g !== null) {
        if (h.xIntersect < g.xIntersect) {
            g = null
        } else {
            f = g;
            g = g.nextp
        }
    }
    h.nextp = f.nextp;
    f.nextp = h
};
Gfx.buildAET = function(d, e, k, h) {
    var f = null;
    var g = k[d].nextp;
    while (g !== null) {
        f = g.nextp;
        Gfx.insertEdge(e, g);
        g = f
    }
};
Gfx.deleteAfter = function(e) {
    var d = e.nextp;
    e.nextp = d.nextp;
    delete d
};
Gfx.updateAET = function(d, e, h) {
    var f = e;
    var g = e.nextp;
    while (g !== null) {
        if ((d + h.y) >= g.yUpper) {
            g = g.nextp;
            Gfx.deleteAfter(f)
        } else {
            g.xIntersect += g.dx;
            f = g;
            g = g.nextp
        }
    }
};
Gfx.resortAET = function(d) {
    var e = null;
    var f = d.nextp;
    d.nextp = null;
    while (f !== null) {
        e = f.nextp;
        Gfx.insertEdge(d, f);
        f = e
    }
};
Gfx.fillScan = function(d, e, g, k) {
    var h = null;
    var f;
    var m = g.nextp;
    while ((m !== null) && (m.nextp !== null)) {
        h = m.nextp;
        d.fillRect(Math.round(m.xIntersect), e + k.y, Math.round(h.xIntersect) - Math.round(m.xIntersect) + 1, 1);
        m = h.nextp
    }
};