5 <meta name=
"viewport" content=
"width=device-width, initial-scale=1" />
8 href=
"data:image/svg+xml;base64,@FAVICON@" />
11 CharmBypass: got that transit equity
16 /* For consistency with the SVG */
17 font-family: sans-serif;
34 /* Display form errors for the one browser that doesn't support
35 * them natively, mobile Firefox. We use "visibility" to toggle
36 * it on and off, but "display" to hide it completely in non-
37 * stupid web browsers. */
45 /* Set the height to
100% of the screen, which we'll keep; and the
46 * initial position to (
0,
0), which we're going to change
47 * every time the window is resized, because the exact amount
48 * that we have to slide the SVG to the left to get the ticket
49 * into the center will change. */
55 /* Hide everything by default. We only show it once the user has
56 * submitted the menu form */
60 /* The blinking fade in/out animation for the ticket date and time */
67 #tickettime, #ticketdate {
68 /*
300 two-second blinks is ten minutes */
69 animation: blink
2s linear
300;
72 /* Define, load, and specify the custom font we use for the ticket
73 * date, time, and service name. */
75 font-family: "CharmBypass Regular";
77 url("data:font/woff2;base64,@CBPREGULAR@") format("woff2")
80 #origindest, #servicename, #tickettime, #ticketdate, #codetext, #zone {
81 font-family: "CharmBypass Regular", sans-serif;
85 font-family: "CharmBypass Bold";
87 url("data:font/woff2;base64,@CBPBOLD@") format("woff2")
91 font-family: "CharmBypass Bold", sans-serif;
94 /************************/
95 /* Scrolling animations */
96 /************************/
100 from { transform: translateX(
0%); }
101 to { transform: translateX(-
100%); }
105 animation: busroll
15s linear infinite;
110 @keyframes tramroll {
111 from { transform: translateX(
0%); }
112 to { transform: translateX(
100%); }
116 animation: tramroll
15s linear infinite;
121 @keyframes trainroll {
122 from { transform: translateX(
0%); }
123 to { transform: translateX(
100%); }
127 animation: trainroll
10s linear infinite;
132 @keyframes cloudsfloat {
133 from { transform: translateX(
0%); }
134 to { transform: translateX(-
50%); }
138 animation: cloudsfloat
25s linear infinite;
141 @keyframes cloudscopyfloat {
142 from { transform: translateX(
0%); }
143 to { transform: translateX(-
50%); }
147 animation: cloudscopyfloat
25s linear infinite;
152 @keyframes treespass {
153 from { transform: translateX(
0%); }
154 to { transform: translateX(-
50%); }
158 /* The trees move a little faster than the clouds */
159 animation: treespass
16s linear infinite;
162 @keyframes treescopypass {
163 from { transform: translateX(
0%); }
164 to { transform: translateX(-
50%); }
168 /* The trees move a little faster than the clouds */
169 animation: treescopypass
16s linear infinite;
174 @keyframes cityscroll {
175 from { transform: translateX(
0%); }
176 to { transform: translateX(-
50%); }
180 /* The city moves faster than the clouds but slower
182 animation: cityscroll
20s linear infinite;
185 @keyframes citycopyscroll {
186 from { transform: translateX(
0%); }
187 to { transform: translateX(-
50%); }
191 /* The city moves faster than the clouds but slower
193 animation: citycopyscroll
20s linear infinite;
201 <p><strong>got that
<em>transit equity
</em></strong></p>
205 <a href=
"https://michael.orlitzky.com/articles/charmbypass_pt._1%3A_introduction.xhtml">
210 <a href=
"https://michael.orlitzky.com/articles/charmbypass_pt._2%3A_analysis.xhtml">
218 <legend>Local Bus, Light Rail, or Metro
</legend>
221 Daily security code (optional):
229 pattern=
"[a-zA-Z0-9]*" />
231 <input type=
"hidden" name=
"servicename" value=
"BaltimoreLink" />
232 <input type=
"submit" name=
"go" value=
"Generate Ticket" />
237 <legend>Commuter Bus
</legend>
238 <input type=
"hidden" name=
"serviceid" value=
"R" />
239 <input type=
"hidden" name=
"servicename" value=
"Commuter Bus" />
243 Daily security code (optional):
251 pattern=
"[a-zA-Z0-9]*" />
255 Zone
<sup>†</sup>:
258 <input type=
"radio" required
262 <label for=
"zone1">Zone
1</label>
265 <input type=
"radio" required
269 <label for=
"zone2">Zone
2</label>
272 <input type=
"radio" required checked
276 <label for=
"zone3">Zone
3</label>
279 <input type=
"radio" required
283 <label for=
"zone4">Zone
4</label>
286 <input type=
"radio" required
290 <label for=
"zone5">Zone
5</label>
293 <input type=
"submit" name=
"go" value=
"Generate Ticket" />
297 On the MTA's PDF schedule for your route
303 <legend>MARC Train
</legend>
307 Daily security code (optional):
315 pattern=
"[a-zA-Z0-9]*" />
320 <input type=
"radio" required checked
324 <label for=
"origin1">Baltimore/Penn (Penn Line)
</label>
327 <input type=
"radio" required
331 <label for=
"origin2">Baltimore/Camden (Camden Line)
</label>
334 <input type=
"radio" required
338 <label for=
"origin3">Bowie State (Penn Line)
</label>
341 <input type=
"radio" required
345 <label for=
"origin4">BWI Airport (Penn Line)
</label>
348 <input type=
"radio" required
352 <label for=
"origin5">College Park (Camden Line)
</label>
355 <input type=
"radio" required
359 <label for=
"origin6">Seabrook (Penn Line)
</label>
362 <input type=
"radio" required
366 <label for=
"origin7">Washington D.C.
</label>
369 <input type=
"radio" required
373 <label for=
"origin8">West Baltimore (Penn Line)
</label>
378 <input type=
"radio" required
382 <label for=
"destination1">Baltimore/Penn (Penn Line)
</label>
385 <input type=
"radio" required
389 <label for=
"destination2">Baltimore/Camden (Camden Line)
</label>
392 <input type=
"radio" required
396 <label for=
"destination3">Bowie State (Penn Line)
</label>
399 <input type=
"radio" required
403 <label for=
"destination4">BWI Airport (Penn Line)
</label>
406 <input type=
"radio" required
410 <label for=
"destination5">College Park (Camden Line)
</label>
413 <input type=
"radio" required
417 <label for=
"destination6">Seabrook (Penn Line)
</label>
420 <input type=
"radio" required checked
424 <label for=
"destination7">Washington D.C.
</label>
427 <input type=
"radio" required
431 <label for=
"destination8">West Baltimore (Penn Line)
</label>
434 <p id=
"marc-form-errors">OK
</p>
436 <input type=
"hidden" name=
"serviceid" value=
"R" />
437 <input type=
"hidden" name=
"servicename" value=
"MARC Train" />
441 value=
"Generate Ticket" />
451 * Center the ticket within the browser by translating the SVG
452 * until the ticket and the viewport centerlines coincide.
454 function center_ticket() {
455 /* We're relying on the SVG being the full height of the
456 * viewport already, and on the aspect ratio being
457 * preserved. First, find the center of the ticket. */
458 const r = document.getElementById("ticket").getBoundingClientRect();
459 const c = r.left + (r.width /
2);
461 /* That's the center-line of the ticket. We want to move it to
462 * the center-line of the viewport. */
463 const vc = document.documentElement.clientWidth /
2;
465 /* This is how much we need to translate the SVG */
466 const hdelta = vc - c;
468 /* But before we can set the absolute left-coordinate of the
469 * SVG, we need to know where it is now. Note: without the
470 * "px" this doesn't default to pixels like CSS does. */
471 const svg = document.querySelector("svg");
472 svg.style.left = (svg.getBoundingClientRect().left + hdelta) + "px";
477 * Set the service identifier from the querystring if it's there.
478 * Otherwise, leave it at the default of "F".
480 function set_service_id() {
481 const sid = document.getElementById("serviceid");
483 /* Get the "serviceid" from the querystring if it's there */
484 const params = new URLSearchParams(document.location.search);
485 if (params.get("serviceid")) {
486 sid.textContent = params.get("serviceid");
492 * Set the service name from the querystring if it's there.
493 * Otherwise, leave it at the default of "BaltimoreLink".
495 function set_service_name() {
496 const sid = document.getElementById("servicename");
498 /* Get the "servicename" from the querystring if it's there */
499 const params = new URLSearchParams(document.location.search);
500 if (params.get("servicename")) {
501 sid.textContent = params.get("servicename");
507 * Set the zone from the given "zone" parameter and then unhide it.
509 function set_zone(zone) {
510 const z = document.getElementById("zone");
512 z.textContent = zone;
513 z.style.display = "block"; /* hidden by default */
518 * Resize the ticket background based on the service name.
519 * The BaltimoreLink, Commuter Bus, and MARC Train tickets
520 * are all different heights and are arranged vertically a
523 * Rather than design three completelty separate tickets and
524 * then have to keep track of which one we're using, I have
525 * instead decided to use one ticket and to reposition it
526 * on-the-fly based on the service name. This is necessarily
527 * a bit ugly because it involves a lot of magic numbers that
528 * can only be explained if you open up inkscape with a CharmPass
529 * screenshot to see where things belong and how to get them there.
531 * The SVG was designed with BaltimoreLink in mind, so this
532 * is a no-op if the service is BaltimoreLink.
534 function resize_ticket() {
535 /* Get the "servicename" from the querystring if it's there */
536 const params = new URLSearchParams(document.location.search);
537 const tbg = document.getElementById("ticketbg");
538 const t = document.getElementById("ticket");
539 const sn = document.getElementById("servicename");
541 if (params.get("servicename") === "Commuter Bus") {
542 /* The top of the background is initially at y=
246.859, and
543 * we scale it by a factor of
1.12 to y=
276.482 for a change
544 * of
29.623. So after we scale it, we translate it upwards
545 * by that amount to put it back where it started. */
546 tbg.setAttribute("transform", "translate(
0 -
29.623) scale(
1 1.12)");
548 /* Now translate the entire ticket up by the magic amount,
1/
5
549 * of the size change we made to the background. This ratio
550 * was found by measuring pixels in side-by-side screenshots
551 * of BaltimoreLink and Commuter Bus tickets. */
552 t.setAttribute("transform", "translate(
0 -
9.33)");
554 /* More magic numbers discovered by comparing the two
555 * tickets overlayed in inkscape */
556 sn.setAttribute("transform", "translate(
0 64.28)");
558 else if (params.get("servicename") === "MARC Train") {
559 /* insane tricks are explained above */
560 tbg.setAttribute("transform",
561 "translate(
0 -
72.378) scale(
1 1.2932)");
562 t.setAttribute("transform", "translate(
0 -
67.17)");
563 sn.setAttribute("transform", "translate(
0 131.0)");
569 * Set the security code from the querystring if it was given;
570 * otherwise generate a random code.
572 function set_code() {
573 const ct = document.getElementById("codetext");
575 /* Get the "code" from the querystring if it's there */
576 const params = new URLSearchParams(document.location.search);
577 if (params.get("code")) {
578 ct.textContent = params.get("code").toUpperCase();
581 /* Otherwise, use a random code */
582 const bucket = ["
0","
1","
2","
3","
4","
5","
6","
7","
8","
9",
583 "A","B","C","D","E","F","G","H","I","J",
584 "K","L","M","N","O","P","Q","R","S","T",
585 "U","V","W","X","Y","Z"];
587 /* Two random ints between
0 and
35 */
588 const i1 = Math.floor(Math.random() *
36);
589 const i2 = Math.floor(Math.random() *
36);
590 const d1 = bucket[i1];
591 const d2 = bucket[i2];
592 ct.textContent = d1 + d2;
598 * Center the security code within its container.
600 * Some codes like "II" and "WW" can take up wildly different
601 * amounts of horizonetal space, but they should always be
602 * centered inside their little red box. This turns out to be
603 * harder than it sounds because we can only find the width of
604 * the code in browser coordinates, whereas its "x" coordinate
605 * is in SVG coordinates. Anyway, we do it.
607 function center_code() {
608 /* Center the security code inside its red box */
609 const ct = document.getElementById("codetext");
610 const bg = document.getElementById("codebg");
612 /* First, find the center of the red box */
613 const r1 = bg.getBoundingClientRect();
614 const c1 = r1.left + (r1.width /
2);
616 /* Now the center of the code text */
617 const r2 = ct.getBoundingClientRect();
618 const c2 = r2.left + (r2.width /
2);
620 /* What do we add to c2 to make it equal to c1? */
621 const hdelta = c1 - c2;
623 /* We've measured everything so far in "client rect"
624 * coordinates, because that's the only available measurement
625 * we have for the width of the
<text> element. But when we
626 * reposition that
<text> element, it will be by adjusting its
627 * "x" attribute, and that attribute uses a different coordinate
628 * system than the client rect does. Specifically, "x" refers to
629 * an offset within the SVG's coordinate system, and the client
630 * rect coordinates are pixels on-screen. To convert between the
631 * two, we can take the "width" attribute of the background
632 * element and compare it to the width of the background
633 * element's client rect. Since the size of the background is
634 * fixed, this should give us a multiplier that turns client rect
635 * distances (what we have) into SVG distances (what we want) */
636 const client_to_svg = parseFloat(bg.getAttribute("width"))/r1.width;
638 /* Convert hdelta from client rect to SVG coordinates */
639 const svg_hdelta = hdelta * client_to_svg;
641 /* Since this
<text> element has an "x" attribute it's easier for
642 * us to shift that than it is to mess with the "left" style. */
643 ct.setAttribute("x", parseFloat(ct.getAttribute("x")) + svg_hdelta);
647 * Set the ticket's expiration date and time.
649 * BaltimoreLink and MARC Train tickets expire after
90 minutes;
650 * while Commuter Bus tickets expire after
10 minutes.
652 function set_ticket_expiry() {
653 /* There are two parameters, time and date, that we store in one
654 * underlying "date" variable. */
655 const date = new Date();
657 /* BaltimoreLink and MARC Train */
659 const params = new URLSearchParams(document.location.search);
660 if (params.get("servicename") === "Commuter Bus") {
661 /* Commuter bus tickets are only valid for ten minutes */
665 /* We use the low-level get/setTime to change the number of
666 * milliseconds since the epoch that this date represents
667 * Obviously correct, and avoids all suspicious corner cases
668 * for a few more decades. */
669 date.setTime(date.getTime() + (minutes*
60*
1000));
671 tt = document.getElementById("tickettime");
672 tt.textContent = date.toLocaleTimeString();
674 const td = document.getElementById("ticketdate");
680 td.textContent = date.toLocaleDateString("en-US", dateopts);
685 * Swap the day/night sky colors.
687 * We use CSS classes to keep track of the current state because
688 * it's a tiny bit cleaner than a global variable, but for some
689 * reason we can't use those same classes to actually change the
690 * color. (The classes, change, but the color doesn't.) Rather
691 * than waste time trying to explain this, we just set the "fill"
692 * attribute ourselves whenever we swap classes.
694 function swap_day_night() {
695 const sky = document.getElementById("sky");
697 if (sky.getAttribute("class") === "night") {
698 sky.setAttribute("fill", "#efb02f");
699 sky.setAttribute("class", "day");
702 /* Put this case second so that the first time the
703 * screen is tapped (when there are no classes on
704 * the sky element) the color still changes. */
705 sky.setAttribute("fill", "#
143b66");
706 sky.setAttribute("class", "night");
712 * Compute the zone (string) for the given origin/destination pair.
714 * If we don't know it or if you chose in invalid pair (destination
715 * not on the same line as your origin?) then null is returned.
717 function compute_marc_zone(src, dest) {
719 /* Sorted on the first component, then the second.
748 /* Forward direction key for zone_map */
749 const fwd = src +
"_" + dest;
751 /* Reverse direction key for zone_map. The zone_map only
752 * has them listed in one direction, so we check both
753 * directions here. */
754 const rev = dest +
"_" + src;
756 /* The default. Obviously wrong for when we don't
757 * have the necessary data. */
761 zone = zone_map[fwd];
763 else if (zone_map[rev]) {
764 zone = zone_map[rev];
767 /* Convert the number to a string */
784 * Compute and set the zone.
786 * We can be given a zone in two ways. First, on Commuter Bus
787 * tickets, it is given explicitly via the querystring. But
788 * It can also be specified implicitly via the origin and
789 * destination on a MARC Train ticket. Here we try both and
790 * then call set_zone() with the result if something worked.
792 function compute_and_set_zone() {
793 const params = new URLSearchParams(document.location.search);
794 const src = params.get(
"origin");
795 const dest = params.get(
"destination");
798 /* MARC Train. We can assume that compute_marc_zone() doesn't
799 * return null because that's part of our form validation. */
800 const zone = compute_marc_zone(src, dest);
803 else if (params.get(
"zone")) {
805 set_zone(params.get(
"zone"));
811 * Set the origin and destination for the MARC Train if they
812 * were provided, and unhide them if so.
814 function set_marc_origin_destination() {
815 const params = new URLSearchParams(document.location.search);
816 if (!params.get(
"origin") || !params.get(
"destination")) {
820 const src = params.get(
"origin");
821 const dest = params.get(
"destination");
823 /* origindest contains both the origin and destination */
824 const origindest = document.getElementById(
"origindest");
826 const origin = document.getElementById(
"origin");
827 const destination = document.getElementById(
"destination");
829 origin.textContent = params.get(
"origin");
830 destination.textContent = params.get(
"destination");
832 origindest.style.display =
"block"; /* hidden by default */
837 * Hide the menu and display the ticket. This is what happens
838 * when you submit the form.
841 /* To create our
"window" onto the scene, we're going to slide the
842 * SVG off the left-hand side of the screen, and we don't want
843 * scroll bars to appear. */
844 document.body.style.overflow =
"hidden";
845 document.body.style.margin =
"0";
846 document.body.style.padding =
"0";
848 const svg = document.querySelector(
"svg");
849 const menu = document.getElementById(
"menu");
850 svg.style.display =
"initial";
851 menu.style.display =
"none";
855 * Determine if the user agent is mobile Firefox.
857 function ua_is_mobile_ff() {
858 const ua = navigator.userAgent.toLowerCase();
859 return (ua.includes(
"firefox") && ua.includes(
"mobile"));
863 * Validate the MARC form's origin/destination.
865 * We don't want the user to be able to choose a pair of stops that
866 * aren't actually connected by the same MARC line. If we don't have
867 * zone information for the (origin,destination) pair, that indicates
868 * that it's probably not a valid choice; otherwise I would have
869 * filled in the information from the CharmPass app already.
871 * All browsers except mobile Firefox let us call setCustomValidity()
872 * to provide an error message that is displayed if the user tries
873 * to submit invalid choices. But amazingly, mobile Firefox does not:
875 * https://bugzilla.mozilla.org/show_bug.cgi?id=
1510450
877 * Instead we have to work around it (in that one browser) by
878 * showing/hiding a paragraph that we fill with the errors.
880 function validate_origin_destination(event) {
881 const origins = document.getElementsByName(
"origin");
882 const destinations = document.getElementsByName(
"destination");
883 const mfe = document.getElementById(
"marc-form-errors");
884 const marcsubmit = document.getElementById(
"marc-submit");
886 if (ua_is_mobile_ff()) {
887 /* Even though this is only for one browser, empty paragraphs
888 * are handled inconsistently and should be avoided as a rule.
889 * So, we make it say
"OK" before we hide it. */
890 mfe.textContent =
"OK";
891 mfe.style.visibility =
"hidden";
892 marcsubmit.disabled = false;
897 origins.forEach((x) =
> { if (x.checked) src = x; })
898 destinations.forEach((x) =
> {
899 if (x.checked) dest = x;
901 /* clear all errors before possibly setting one */
902 x.setCustomValidity('');
905 if (src.value === dest.value) {
906 let err = "Origin and destination are the same";
907 dest.setCustomValidity(err);
909 if (ua_is_mobile_ff()) {
910 mfe.textContent = err;
911 mfe.style.visibility = "visible";
912 marcsubmit.disabled = true;
915 else if (compute_marc_zone(src.value, dest.value) === null) {
916 let err = "Origin and destination are on different lines";
917 dest.setCustomValidity(err);
919 if (ua_is_mobile_ff()) {
920 mfe.textContent = err;
921 mfe.style.visibility = "visible";
922 marcsubmit.disabled = true;
927 /*****************************************************/
928 /* Add event handlers for all of the functions above */
929 /*****************************************************/
931 const params = new URLSearchParams(document.location.search);
932 if (params.get("go")) {
933 /* First unhide the SVG (swap it with the form) */
934 window.addEventListener("load", go);
936 /* Center the ticket once when the page has loaded */
937 window.addEventListener("load", center_ticket);
939 /* Re-center the ticket when the window is resized */
940 window.addEventListener("resize", center_ticket);
942 /* Set the service identifier when the page has loaded */
943 window.addEventListener("load", set_service_id);
945 /* Set the service name when the page has loaded */
946 window.addEventListener("load", set_service_name);
948 /* Resize the ticket background if necessary */
949 window.addEventListener("load", resize_ticket);
951 /* Set the security code text when the page has loaded */
952 window.addEventListener("load", set_code);
954 /* Center the security code text when the page has loaded; in
955 * particular, after we set the code. */
956 window.addEventListener("load", center_code);
958 /* Set the ticket expiration date/time upon page load */
959 window.addEventListener("load", set_ticket_expiry);
961 /* Set the MARC Train origin and destination, if applicable */
962 window.addEventListener("load", set_marc_origin_destination);
964 /* Compute and set the zone, if applicable */
965 window.addEventListener("load", compute_and_set_zone);
967 /* Swap colors when the screen is tapped */
968 document.body.addEventListener("click", swap_day_night);
971 /* If we haven't submitted the form yet, set up change handlers
972 * for the origin/destination radio buttons that validate that
973 * the origin and destination are on the same line. */
974 document.getElementsByName("origin").forEach(
975 (x) =
> x.addEventListener("change", validate_origin_destination)
977 document.getElementsByName("destination").forEach(
978 (x) =
> x.addEventListener("change", validate_origin_destination)
981 /* Also do it when the page loads, because firefox likes to
982 * remember your selection even after the page reloads. */
983 window.addEventListener("load", validate_origin_destination);
985 /* Finally, we have to babysit mobile Firefox, who doesn't
986 * support HTML5 form validation going into
2024. Turn on
987 * the little form errors paragraph so we can toggle its
988 * visibility (and make it display the error) when the user
989 * makes an invalid selection. */
990 window.addEventListener("load", () =
> {
991 if (ua_is_mobile_ff()) {
992 const mfe = document.getElementById("marc-form-errors");
993 mfe.style.display = "block";