new exercise in unit 1, vocabulary training

exercise_u1.c

@@ -977,3 +977,277 @@ GtkWidget *build_assign(UnitCtx *unit, const char *title,
     g_signal_connect(check, "clicked", G_CALLBACK(assign_check), ac);
     return page;
 }
+
+/* ------------------------------------------------------------------ */
+/* Exercise 14: Wörter übersetzen                                     */
+/* ------------------------------------------------------------------ */
+
+const TypedQ trans_p10[] = {
+    {"der Abend, -e", "večer|evening", "večer"},
+    {"Guten Abend!", "dobrý večer|good evening", "Dobrý večer!"},
+    {"du", "ty|you", "ty"},
+    {"(Es) freut mich.", "těší mě|nice to meet you", "Těší mě."},
+    {"gut", "dobrý|good", "dobrý"},
+    {"Hallo!", "ahoj|hello", "Ahoj!"},
+    {"heißen, er heißt", "jmenovat se|to be called|to be named", "jmenovat se"},
+    {"Ich heiße Jens.", "jmenuji se jens|my name is jens", "Jmenuji se Jens."},
+    {"Hi!", "ahoj|hi", "Ahoj! (neformálně)"},
+    {"ich", "já|i", "já"},
+    {"ihr", "vy|you", "vy"},
+    {"ja", "ano|yes", "ano"},
+    {"der Morgen", "ráno|morning", "ráno"},
+    {"Guten Morgen!", "dobré ráno|good morning", "Dobré ráno!"},
+    {"der Name, -n", "jméno|name", "jméno"},
+    {"nein", "ne|no", "ne"},
+    {"(er/sie/es) ist", "je|is", "je"},
+    {"der Tag, -e", "den|day", "den"},
+    {"Guten Tag!", "dobrý den|good day", "Dobrý den!"},
+    {"und", "a|and", "a"},
+    {"wer", "kdo|who", "kdo"},
+    {"Wer bist du?", "kdo jsi|who are you", "Kdo jsi?"},
+    {"wie", "jak|how", "jak"},
+    {"Wie heißt du?", "jak se jmenuješ|what is your name", "Jak se jmenuješ?"},
+    {"wir", "my|we", "my"},
+};
+
+const TypedQ trans_p11[] = {
+    {"in", "v|in", "v"},
+    {"in der Nähe (von)", "poblíž|v blízkosti|near|nearby", "poblíž, v blízkosti"},
+    {"das Spiel, -e", "hra|game", "hra"},
+    {"wo", "kde|where", "kde"},
+    {"wohnen, er wohnt", "bydlet|to live", "bydlet"},
+    {"Wo wohnst du?", "kde bydlíš|where do you live", "Kde bydlíš?"},
+    {"Ich wohne in Prag.", "bydlím v praze|i live in prague", "Bydlím v Praze."},
+    {"null", "nula|zero", "nula"},
+    {"eins", "jedna|one", "jedna"},
+    {"zwei", "dvě|two", "dvě"},
+    {"drei", "tři|three", "tři"},
+    {"vier", "čtyři|four", "čtyři"},
+    {"fünf", "pět|five", "pět"},
+    {"sechs", "šest|six", "šest"},
+    {"sieben", "sedm|seven", "sedm"},
+    {"acht", "osm|eight", "osm"},
+    {"neun", "devět|nine", "devět"},
+    {"zehn", "deset|ten", "deset"},
+    {"elf", "jedenáct|eleven", "jedenáct"},
+    {"zwölf", "dvanáct|twelve", "dvanáct"},
+    {"dreizehn", "třináct|thirteen", "třináct"},
+    {"vierzehn", "čtrnáct|fourteen", "čtrnáct"},
+    {"fünfzehn", "patnáct|fifteen", "patnáct"},
+    {"sechzehn", "šestnáct|sixteen", "šestnáct"},
+    {"siebzehn", "sedmnáct|seventeen", "sedmnáct"},
+    {"achtzehn", "osmnáct|eighteen", "osmnáct"},
+    {"neunzehn", "devatenáct|nineteen", "devatenáct"},
+    {"zwanzig", "dvacet|twenty", "dvacet"},
+};
+
+const TypedQ trans_p12[] = {
+    {"alt", "starý|old", "starý"},
+    {"er", "on|he", "on"},
+    {"der Monat, -e", "měsíc|month", "měsíc"},
+    {"sie", "ona|she", "ona"},
+    {"sie", "oni|they", "oni"},
+};
+
+const TypedQ trans_p13[] = {
+    {"aber", "ale|but", "ale"},
+    {"das Alter", "věk|age", "věk"},
+    {"auch", "také|also|too", "také"},
+    {"aus", "z|from", "z"},
+    {"die Band, -s", "skupina|band", "(hudební) skupina"},
+    {"chatten, er chattet", "chatovat|to chat", "chatovat"},
+    {"das Computerspiel, -e", "počítačová hra|computer game", "počítačová hra"},
+    {"die/das E-Mail, -s", "e-mail|email", "e-mail"},
+    {"das Englisch", "angličtina|anglicky|english", "angličtina, anglicky"},
+    {"der Fan, -s", "fanoušek|fan", "fanoušek"},
+    {"das Französisch", "francouzština|francouzsky|french",
+     "francouzština, francouzsky"},
+    {"der Freund, -e", "kamarád|friend", "kamarád"},
+    {"die Freundin, -nen", "kamarádka|friend", "kamarádka"},
+    {"beste Freundin", "nejlepší kamarádka|best friend", "nejlepší kamarádka"},
+    {"der Fußball", "fotbal|football", "fotbal"},
+    {"Er ist Fußballfanatiker.", "je fotbalový fanatik|he is a football fanatic",
+     "Je fotbalový fanatik."},
+    {"gehen, er geht", "jít|to go", "jít"},
+    {"Ich gehe gern auf Konzerte.",
+     "rád chodím na koncerty|ráda chodím na koncerty|i like going to concerts",
+     "Rád(a) chodím na koncerty."},
+    {"gern", "rád|ráda|gladly", "rád/a"},
+    {"die Gitarre, -n", "kytara|guitar", "kytara"},
+    {"das Handy, -s", "mobil|mobile phone", "mobil"},
+    {"das Hobby, -s", "koníček|hobby", "koníček"},
+    {"hören, er hört", "poslouchat|to listen", "poslouchat"},
+    {"Er hört gern Musik.", "rád poslouchá hudbu|he likes listening to music",
+     "Rád poslouchá hudbu."},
+    {"im Internet surfen, er surft im Internet",
+     "surfovat na internetu|to surf the internet", "surfovat na internetu"},
+    {"immer", "pořád|neustále|always", "pořád, neustále"},
+    {"das Jahr, -e", "rok|year", "rok"},
+    {"kein/keine/kein", "žádný|žádná|žádné|no|none", "žádný/žádná/žádné"},
+    {"das Klavier, -e", "klavír|piano", "klavír"},
+    {"kommen (aus), er kommt", "přicházet|pocházet|to come|to come from",
+     "přicházet, pocházet (z)"},
+    {"Er kommt aus Wien.", "pochází z vídně|he comes from vienna",
+     "Pochází z Vídně."},
+    {"das Konzert, -e", "koncert|concert", "koncert"},
+    {"lernen, er lernt", "učit se|to learn", "učit se"},
+    {"liegen, er liegt", "ležet|to lie", "ležet"},
+    {"der Nachname, -n", "příjmení|surname|last name", "příjmení"},
+    {"nicht weit von", "nedaleko od|not far from", "nedaleko od"},
+    {"reisen, er reist", "cestovat|to travel", "cestovat"},
+    {"schreiben, er schreibt", "psát|to write", "psát"},
+    {"die Schule, -n", "škola|school", "škola"},
+    {"spielen, er spielt", "hrát|to play", "hrát"},
+    {"Sie spielt Gitarre.", "hraje na kytaru|she plays the guitar",
+     "Hraje na kytaru."},
+    {"tanzen, er tanzt", "tancovat|to dance", "tancovat"},
+    {"der Vorname, -n", "křestní jméno|first name", "křestní jméno"},
+    {"der Wohnort, -e", "bydliště|place of residence", "bydliště"},
+};
+
+const TypedQ trans_p14[] = {
+    {"falsch", "nesprávně|chybně|wrong|incorrect", "nesprávně, chybně"},
+    {"die Flöte, -n", "flétna|flute", "flétna"},
+    {"haben, er hat", "mít|to have", "mít"},
+    {"das Instrument, -e", "nástroj|instrument", "(hudební) nástroj"},
+    {"jetzt", "teď|now", "teď"},
+    {"machen, er macht", "dělat|to do|to make", "dělat"},
+    {"richtig", "správně|correct|right", "správně"},
+    {"der Sport", "sport", "sport"},
+    {"Sport treiben, er treibt Sport", "sportovat|to do sport", "sportovat"},
+    {"das Squash", "squash", "squash"},
+    {"das/der Yoga", "jóga|yoga", "jóga"},
+};
+
+const TypedQ trans_p15[] = {
+    {"bald", "brzy|soon", "brzy"},
+    {"Bis bald!", "brzy na shledanou|see you soon", "Brzy na shledanou!"},
+    {"bis", "do|until", "do"},
+    {"Bis zum nächsten Mal!", "do příštího setkání|until next time",
+     "Do příštího setkání!"},
+    {"die Frau, -en", "paní|woman|mrs", "paní"},
+    {"der Herr, -en", "pan|man|mr", "pan"},
+    {"Mach's gut!", "měj se hezky|take care", "Měj se hezky!"},
+    {"das Museum, Museen", "muzeum|museum", "muzeum"},
+    {"Sie gehen ins Museum.", "jdou do muzea|they are going to the museum",
+     "Jdou do muzea."},
+    {"schön", "hezký|beautiful|nice", "hezký"},
+    {"Einen schönen Tag noch!", "hezký zbytek dne|have a nice day",
+     "Hezký zbytek dne!"},
+    {"Servus!", "ahoj|hi", "Ahoj! (servus)"},
+    {"Tschüs!", "ahoj|bye", "Ahoj! (při loučení)"},
+    {"das Wiedersehen", "shledání|reunion", "shledání"},
+    {"Auf Wiedersehen!", "na shledanou|goodbye", "Na shledanou!"},
+};
+
+typedef struct {
+    const char *header;   /* i18n key, e.g. "Strana 10" */
+    const TypedQ *rows;
+    int n;
+} TransSection;
+
+static const TransSection trans_sections[] = {
+    {"Strana 10", trans_p10, (int)G_N_ELEMENTS(trans_p10)},
+    {"Strana 11", trans_p11, (int)G_N_ELEMENTS(trans_p11)},
+    {"Strana 12", trans_p12, (int)G_N_ELEMENTS(trans_p12)},
+    {"Strana 13", trans_p13, (int)G_N_ELEMENTS(trans_p13)},
+    {"Strana 14", trans_p14, (int)G_N_ELEMENTS(trans_p14)},
+    {"Strana 15", trans_p15, (int)G_N_ELEMENTS(trans_p15)},
+};
+
+typedef struct {
+    UnitCtx *unit;
+    int ex_num;
+    GtkWidget *feedback;
+    GtkWidget **entries;
+    GtkWidget **trans;
+    int total;
+} TransCtx;
+
+static void translate_check(GtkButton *button, gpointer data) {
+    TransCtx *ctx = data;
+    int ok = 0;
+    int idx = 0;
+
+    (void)button;
+
+    for (guint s = 0; s < G_N_ELEMENTS(trans_sections); s++) {
+        const TransSection *sec = &trans_sections[s];
+        for (int i = 0; i < sec->n; i++, idx++) {
+            const gchar *txt =
+                gtk_editable_get_text(GTK_EDITABLE(ctx->entries[idx]));
+            gchar *norm = normalize_answer(txt);
+            gboolean good =
+                txt && txt[0] && answer_accepts(norm, sec->rows[i].answers);
+
+            g_free(norm);
+            answer_mark(ctx->entries[idx], good);
+            if (good)
+                ok++;
+        }
+    }
+
+    for (int i = 0; i < ctx->total; i++)
+        if (ctx->trans[i])
+            gtk_widget_set_visible(ctx->trans[i], TRUE);
+
+    if (ok == ctx->total) {
+        set_feedback(ctx->feedback, TRUE, tr("feedback_ok"));
+        mark_done(ctx->unit, ctx->ex_num);
+    } else {
+        set_feedback(ctx->feedback, FALSE, tr("feedback_retry"));
+    }
+}
+
+GtkWidget *build_translate(UnitCtx *unit) {
+    GtkWidget *body, *feedback, *check;
+    GtkWidget *page = ex_page_shell(unit->page, "Vokabeltraining",
+                                    "sub_translate", "check",
+                                    &body, &feedback, &check);
+    TransCtx *ctx = g_new0(TransCtx, 1);
+    int total = 0;
+    int idx = 0;
+
+    for (guint s = 0; s < G_N_ELEMENTS(trans_sections); s++)
+        total += trans_sections[s].n;
+
+    ctx->unit = unit;
+    ctx->ex_num = unit->branch_ex;
+    ctx->feedback = feedback;
+    ctx->total = total;
+    ctx->entries = g_new0(GtkWidget *, total);
+    ctx->trans = g_new0(GtkWidget *, total);
+
+    for (guint s = 0; s < G_N_ELEMENTS(trans_sections); s++) {
+        const TransSection *sec = &trans_sections[s];
+        GtkWidget *hdr = gtk_label_new(NULL);
+
+        i18n_bind(hdr, sec->header, 0);
+        gtk_widget_set_halign(hdr, GTK_ALIGN_START);
+        gtk_widget_add_css_class(hdr, "ex-sub");
+        gtk_widget_set_margin_top(hdr, s > 0 ? 12 : 0);
+        gtk_box_append(GTK_BOX(body), hdr);
+
+        for (int i = 0; i < sec->n; i++, idx++) {
+            GtkWidget *prompt = gtk_label_new(sec->rows[i].prompt);
+            GtkWidget *entry;
+
+            gtk_widget_set_halign(prompt, GTK_ALIGN_START);
+            gtk_widget_add_css_class(prompt, "ex-prompt");
+            gtk_label_set_wrap(GTK_LABEL(prompt), TRUE);
+            gtk_box_append(GTK_BOX(body), prompt);
+
+            entry = gtk_entry_new();
+            gtk_widget_set_hexpand(entry, FALSE);
+            gtk_widget_set_halign(entry, GTK_ALIGN_START);
+            gtk_box_append(GTK_BOX(body), entry);
+            ctx->entries[idx] = entry;
+
+            if (sec->rows[i].meaning)
+                ctx->trans[idx] = meaning_add(body, sec->rows[i].meaning);
+        }
+    }
+
+    g_signal_connect(check, "clicked", G_CALLBACK(translate_check), ctx);
+    return page;
+}

i18n.c

@@ -75,6 +75,9 @@ const TrEntry tr_ui[] = {
      "Sort the phrases into greetings and farewells."},
     {"sub_land", "Přiřaďte symboly ke správné zemi.",
      "Match the symbols to the correct country."},
+    {"Vokabeltraining", NULL, "Vocabulary training"},
+    {"sub_translate", "Přeložte tato slova – česky nebo anglicky.",
+     "Translate these words – in Czech or English."},
     {"assign_hint",
      "Vyberte skupinu a klikněte na kartu. Kliknutím na kartu ve skupině "
      "ji vrátíte zpět.",
@@ -592,6 +595,130 @@ const TrEntry tr_content[] = {
      "My brother is driving to a lake."},
     {"A já? Navštívím obchodní centrum.", NULL,
      "And me? I am going to a shopping centre."},
+    /* ---- unit 1: Wörter übersetzen (page headers) ---- */
+    {"Strana 10", NULL, "Page 10"},
+    {"Strana 11", NULL, "Page 11"},
+    {"Strana 12", NULL, "Page 12"},
+    {"Strana 13", NULL, "Page 13"},
+    {"Strana 14", NULL, "Page 14"},
+    {"Strana 15", NULL, "Page 15"},
+    /* ---- unit 1: Wörter übersetzen (word meanings) ---- */
+    {"večer", NULL, "evening"},
+    {"Dobrý večer!", NULL, "Good evening!"},
+    {"ty", NULL, "you"},
+    {"Těší mě.", NULL, "Nice to meet you."},
+    {"dobrý", NULL, "good"},
+    {"Ahoj!", NULL, "Hello!"},
+    {"jmenovat se", NULL, "to be called"},
+    {"Jmenuji se Jens.", NULL, "My name is Jens."},
+    {"Ahoj! (neformálně)", NULL, "Hi! (informal)"},
+    {"já", NULL, "I"},
+    {"vy", NULL, "you (plural)"},
+    {"ano", NULL, "yes"},
+    {"ráno", NULL, "morning"},
+    {"jméno", NULL, "name"},
+    {"ne", NULL, "no"},
+    {"je", NULL, "is"},
+    {"den", NULL, "day"},
+    {"Dobrý den!", NULL, "Good day!"},
+    {"a", NULL, "and"},
+    {"kdo", NULL, "who"},
+    {"Kdo jsi?", NULL, "Who are you?"},
+    {"jak", NULL, "how"},
+    {"my", NULL, "we"},
+    {"v", NULL, "in"},
+    {"poblíž, v blízkosti", NULL, "near, in the vicinity"},
+    {"hra", NULL, "game"},
+    {"kde", NULL, "where"},
+    {"bydlet", NULL, "to live"},
+    {"Kde bydlíš?", NULL, "Where do you live?"},
+    {"nula", NULL, "zero"},
+    {"jedna", NULL, "one"},
+    {"dvě", NULL, "two"},
+    {"tři", NULL, "three"},
+    {"čtyři", NULL, "four"},
+    {"pět", NULL, "five"},
+    {"sedm", NULL, "seven"},
+    {"osm", NULL, "eight"},
+    {"devět", NULL, "nine"},
+    {"deset", NULL, "ten"},
+    {"jedenáct", NULL, "eleven"},
+    {"dvanáct", NULL, "twelve"},
+    {"patnáct", NULL, "fifteen"},
+    {"šestnáct", NULL, "sixteen"},
+    {"osmnáct", NULL, "eighteen"},
+    {"devatenáct", NULL, "nineteen"},
+    {"starý", NULL, "old"},
+    {"on", NULL, "he"},
+    {"měsíc", NULL, "month"},
+    {"ona", NULL, "she"},
+    {"oni", NULL, "they"},
+    {"ale", NULL, "but"},
+    {"věk", NULL, "age"},
+    {"také", NULL, "also"},
+    {"(hudební) skupina", NULL, "(music) band"},
+    {"chatovat", NULL, "to chat"},
+    {"počítačová hra", NULL, "computer game"},
+    {"e-mail", NULL, "email"},
+    {"angličtina, anglicky", NULL, "English"},
+    {"fanoušek", NULL, "fan"},
+    {"francouzština, francouzsky", NULL, "French"},
+    {"kamarádka", NULL, "friend (f.)"},
+    {"nejlepší kamarádka", NULL, "best friend (f.)"},
+    {"fotbal", NULL, "football"},
+    {"Je fotbalový fanatik.", NULL, "He is a football fanatic."},
+    {"jít", NULL, "to go"},
+    {"Rád(a) chodím na koncerty.", NULL, "I like going to concerts."},
+    {"rád/a", NULL, "gladly"},
+    {"kytara", NULL, "guitar"},
+    {"mobil", NULL, "mobile phone"},
+    {"koníček", NULL, "hobby"},
+    {"poslouchat", NULL, "to listen"},
+    {"Rád poslouchá hudbu.", NULL, "He likes listening to music."},
+    {"surfovat na internetu", NULL, "to surf the internet"},
+    {"pořád, neustále", NULL, "always"},
+    {"rok", NULL, "year"},
+    {"žádný/žádná/žádné", NULL, "no / none"},
+    {"klavír", NULL, "piano"},
+    {"přicházet, pocházet (z)", NULL, "to come (from)"},
+    {"Pochází z Vídně.", NULL, "He comes from Vienna."},
+    {"koncert", NULL, "concert"},
+    {"ležet", NULL, "to lie"},
+    {"příjmení", NULL, "surname"},
+    {"nedaleko od", NULL, "not far from"},
+    {"cestovat", NULL, "to travel"},
+    {"psát", NULL, "to write"},
+    {"škola", NULL, "school"},
+    {"hrát", NULL, "to play"},
+    {"Hraje na kytaru.", NULL, "She plays the guitar."},
+    {"tancovat", NULL, "to dance"},
+    {"křestní jméno", NULL, "first name"},
+    {"bydliště", NULL, "place of residence"},
+    {"nesprávně, chybně", NULL, "wrong, incorrectly"},
+    {"flétna", NULL, "flute"},
+    {"(hudební) nástroj", NULL, "(musical) instrument"},
+    {"teď", NULL, "now"},
+    {"dělat", NULL, "to do"},
+    {"správně", NULL, "correctly"},
+    {"sport", NULL, "sport"},
+    {"sportovat", NULL, "to do sport"},
+    {"squash", NULL, "squash"},
+    {"jóga", NULL, "yoga"},
+    {"brzy", NULL, "soon"},
+    {"Brzy na shledanou!", NULL, "See you soon!"},
+    {"do", NULL, "until"},
+    {"Do příštího setkání!", NULL, "Until next time!"},
+    {"paní", NULL, "woman / Mrs."},
+    {"pan", NULL, "man / Mr."},
+    {"Měj se hezky!", NULL, "Take care!"},
+    {"muzeum", NULL, "museum"},
+    {"Jdou do muzea.", NULL, "They are going to the museum."},
+    {"hezký", NULL, "beautiful"},
+    {"Hezký zbytek dne!", NULL, "Have a nice rest of the day!"},
+    {"Ahoj! (servus)", NULL, "Hi! (Servus)"},
+    {"Ahoj! (při loučení)", NULL, "Bye!"},
+    {"shledání", NULL, "reunion"},
+    {"Na shledanou!", NULL, "Goodbye!"},
     {NULL, NULL, NULL}
 };
 

main.c

@@ -31,6 +31,12 @@ void unit_meta_init(void) {
     units[1].progress_file = PROGRESS_U2;
     units[2].sub_key = "unit3_sub";
     units[2].progress_file = PROGRESS_U3;
+
+    /* Off-path branch hanging above exercise 2 of unit 1. */
+    units[0].has_branch = TRUE;
+    units[0].branch_name = "Vokabeltraining";
+    units[0].branch_target = "u1vocab";
+    units[0].branch_ex = MAX_UNIT_EX;
 }
 
 void unit_configure(int idx, const char *const *names, int n) {
@@ -183,6 +189,12 @@ void activate(GtkApplication *app, gpointer user_data) {
             g_snprintf(name, sizeof(name), "%se%d", u->ex_tag, n);
             gtk_stack_add_named(main_stack, page, name);
         }
+        if (u->has_branch && u->branch_target) {
+            GtkWidget *branch = build_translate(u);
+
+            if (branch)
+                gtk_stack_add_named(main_stack, branch, u->branch_target);
+        }
     }
 
     gtk_stack_set_visible_child_name(main_stack, "welcome");

maturita.h

@@ -36,6 +36,7 @@
 #define EX_SPAC    150.0   /* horizontal distance between bubbles       */
 #define EX_GAP     200.0   /* vertical space between folded rows        */
 #define EX_WAVE    26.0    /* wavy vertical offset of the bubbles       */
+#define EX_BRANCH_LIFT 150.0  /* extra top space for an off-path branch  */
 #define HM_WORDS 5
 #define HM_MAX_MISSES 6
 #define HM_N_LETTERS 29   /* QWERTY rows + Ä/Ö/Ü (see hm_letters[]) */
@@ -116,6 +117,16 @@ typedef struct {
     double ex_cy[MAX_UNIT_EX];
     int ex_rows, ex_cols, ex_cw, ex_ch;
     guint ex_idle;
+    /* optional off-path branch exercise (e.g. vocabulary training) */
+    gboolean has_branch;
+    const char *branch_name;     /* label under the branch bubble          */
+    const char *branch_target;   /* stack page name                        */
+    int branch_ex;               /* done[] slot used by the branch          */
+    GtkWidget *branch_cell;
+    GtkWidget *branch_label;
+    GtkWidget *branch_icon;
+    double branch_cx;
+    double branch_cy;
 } UnitCtx;
 typedef struct { double r, g, b; } Rgb;
 typedef struct {
@@ -816,6 +827,7 @@ char *verbq_german(const char *before, const char *answer,
                           const char *after);
 GtkWidget *build_ex8(UnitCtx *unit);
 GtkWidget *build_ex12(UnitCtx *unit);
+GtkWidget *build_translate(UnitCtx *unit);
 void assign_rebuild(AssignCtx *ac);
 void assign_chip_clicked(GtkButton *button, gpointer data);
 void assign_group_toggled(GtkToggleButton *button, gpointer data);

progress.c

@@ -6,7 +6,7 @@
 
 void unit_save_progress(UnitCtx *u) {
     GKeyFile *kf = g_key_file_new();
-    for (int i = 1; i <= u->n_ex; i++) {
+    for (int i = 1; i <= MAX_UNIT_EX; i++) {
         gchar key[8];
         g_snprintf(key, sizeof(key), "%d", i);
         g_key_file_set_boolean(kf, "done", key, u->done[i]);
@@ -40,7 +40,7 @@ void unit_load_progress(UnitCtx *u) {
         return;
     }
 
-    for (int i = 1; i <= u->n_ex; i++) {
+    for (int i = 1; i <= MAX_UNIT_EX; i++) {
         gchar key[8];
         g_snprintf(key, sizeof(key), "%d", i);
         u->done[i] = g_key_file_get_boolean(kf, "done", key, NULL);
@@ -92,6 +92,19 @@ void refresh_completion_ui(void) {
             }
         }
 
+        /* off-path branch marker */
+        if (u->has_branch && u->branch_cell) {
+            if (u->done[u->branch_ex]) {
+                gtk_widget_add_css_class(u->branch_cell, "done");
+                if (u->branch_icon)
+                    gtk_widget_set_visible(u->branch_icon, TRUE);
+            } else {
+                gtk_widget_remove_css_class(u->branch_cell, "done");
+                if (u->branch_icon)
+                    gtk_widget_set_visible(u->branch_icon, FALSE);
+            }
+        }
+
         /* roadmap node marker */
         if (u->node) {
             if (all && u->n_ex > 0) {
@@ -113,7 +126,7 @@ void refresh_completion_ui(void) {
 }
 
 void mark_done(UnitCtx *u, int n) {
-    if (!u || n < 1 || n > u->n_ex)
+    if (!u || n < 1 || n > MAX_UNIT_EX)
         return;
     u->done[n] = TRUE;
     refresh_completion_ui();

style.css

@@ -344,6 +344,13 @@ windowcontrols button:not(:hover) image {
 .ex-bubble:focus-visible {
    outline: none;
 }
+.ex-branch {
+   border-style: dashed;
+   border-color: @accent;
+}
+.ex-branch:hover {
+   border-style: solid;
+}
 .bubble-number {
    font-size: 22px;
    font-weight: 800;

unitmap.c

@@ -9,6 +9,7 @@
 void ex_layout_geometry(UnitCtx *u, double avail) {
     const int n = u->n_ex;
     const double phase = 2.0 * G_PI * 1.7 / (double)(n > 1 ? n - 1 : 1);
+    const double lift = u->has_branch ? EX_BRANCH_LIFT : 0.0;
     int rows;
     int r, c, i;
 
@@ -26,7 +27,7 @@ void ex_layout_geometry(UnitCtx *u, double avail) {
     if (u->ex_cols < 1)
         u->ex_cols = 1;
     u->ex_cw = (int)(2.0 * EX_MX + (u->ex_cols - 1) * EX_SPAC);
-    u->ex_ch = (int)(2.0 * EX_MY + (rows - 1) * EX_GAP);
+    u->ex_ch = (int)(2.0 * EX_MY + (rows - 1) * EX_GAP + lift);
 
     for (r = 0; r < rows; r++) {
         int base = r * u->ex_cols;
@@ -36,10 +37,16 @@ void ex_layout_geometry(UnitCtx *u, double avail) {
             i = base + c;
             int cc = fwd ? c : (u->ex_cols - 1 - c);
             u->ex_cx[i] = EX_MX + cc * EX_SPAC;
-            u->ex_cy[i] = EX_MY + r * EX_GAP
+            u->ex_cy[i] = EX_MY + lift + r * EX_GAP
                           + EX_WAVE * sin((double)i * phase);
         }
     }
+
+    /* The branch hangs straight above exercise 2 (index 1). */
+    if (u->has_branch && n > 1) {
+        u->branch_cx = u->ex_cx[1];
+        u->branch_cy = u->ex_cy[1] - EX_BRANCH_LIFT;
+    }
 }
 
 void ex_point(UnitCtx *u, double t, double *ox, double *oy) {
@@ -125,6 +132,28 @@ void draw_ex_rail(GtkDrawingArea *area, cairo_t *cr,
         cairo_set_line_width(cr, 9);
         cairo_stroke(cr);
     }
+
+    /* Off-path branch connector up from exercise 2. */
+    if (u->has_branch && u->n_ex > 1) {
+        gboolean bdone = u->done[u->branch_ex];
+
+        cairo_new_path(cr);
+        cairo_move_to(cr, u->ex_cx[1], u->ex_cy[1]);
+        cairo_line_to(cr, u->branch_cx, u->branch_cy);
+        cairo_set_line_width(cr, 14);
+        cairo_set_source_rgb(cr, rail.r, rail.g, rail.b);
+        cairo_stroke(cr);
+
+        cairo_new_path(cr);
+        cairo_move_to(cr, u->ex_cx[1], u->ex_cy[1]);
+        cairo_line_to(cr, u->branch_cx, u->branch_cy);
+        cairo_set_line_width(cr, 9);
+        if (bdone)
+            cairo_set_source_rgba(cr, green.r, green.g, green.b, 0.85);
+        else
+            cairo_set_source_rgb(cr, slate.r, slate.g, slate.b);
+        cairo_stroke(cr);
+    }
 }
 
 void ex_apply_layout(UnitCtx *u) {
@@ -144,6 +173,16 @@ void ex_apply_layout(UnitCtx *u) {
                            (int)(u->ex_cy[i] + EX_BUBBLE / 2.0 + 8.0));
     }
 
+    if (u->has_branch && u->branch_cell) {
+        gtk_fixed_move(GTK_FIXED(u->ex_fixed), u->branch_cell,
+                       (int)(u->branch_cx - EX_BUBBLE / 2.0),
+                       (int)(u->branch_cy - EX_BUBBLE / 2.0));
+        if (u->branch_label)
+            gtk_fixed_move(GTK_FIXED(u->ex_fixed), u->branch_label,
+                           (int)(u->branch_cx + EX_BUBBLE / 2.0 + 10.0),
+                           (int)(u->branch_cy - 14.0));
+    }
+
     gtk_widget_set_size_request(u->ex_fixed, u->ex_cw, u->ex_ch);
     gtk_widget_set_size_request(u->ex_rail, u->ex_cw, u->ex_ch);
     gtk_fixed_move(GTK_FIXED(u->ex_fixed), u->ex_rail, 0, 0);
@@ -225,6 +264,43 @@ GtkWidget *make_bubble(UnitCtx *u, int n) {
     return btn;
 }
 
+static GtkWidget *make_branch_bubble(UnitCtx *u) {
+    GtkWidget *btn;
+    GtkWidget *vbox;
+    GtkWidget *star;
+    GtkWidget *icon;
+
+    btn = gtk_button_new();
+    gtk_widget_add_css_class(btn, "ex-bubble");
+    gtk_widget_add_css_class(btn, "ex-branch");
+    gtk_widget_set_size_request(btn, (int)EX_BUBBLE, (int)EX_BUBBLE);
+    gtk_widget_set_can_focus(btn, FALSE);
+    if (u->done[u->branch_ex])
+        gtk_widget_add_css_class(btn, "done");
+
+    vbox = gtk_box_new(GTK_ORIENTATION_VERTICAL, 2);
+    gtk_widget_set_halign(vbox, GTK_ALIGN_CENTER);
+    gtk_widget_set_valign(vbox, GTK_ALIGN_CENTER);
+    gtk_button_set_child(GTK_BUTTON(btn), vbox);
+
+    star = gtk_label_new("★");
+    gtk_widget_set_halign(star, GTK_ALIGN_CENTER);
+    gtk_widget_add_css_class(star, "bubble-number");
+    gtk_box_append(GTK_BOX(vbox), star);
+
+    icon = icon_area_new(draw_check_icon, 0.1176, 0.1176, 0.1804, 16);
+    gtk_widget_set_visible(icon, u->done[u->branch_ex]);
+    gtk_box_append(GTK_BOX(vbox), icon);
+
+    u->branch_cell = btn;
+    u->branch_icon = icon;
+
+    g_object_set_data_full(G_OBJECT(btn), "target",
+                           g_strdup(u->branch_target), g_free);
+    g_signal_connect(btn, "clicked", G_CALLBACK(on_nav_clicked), NULL);
+    return btn;
+}
+
 GtkWidget *build_unit_page(UnitCtx *u) {
     GtkWidget *page;
     GtkWidget *scroll;
@@ -293,6 +369,19 @@ GtkWidget *build_unit_page(UnitCtx *u) {
         gtk_fixed_put(GTK_FIXED(fixed), lbl, 0, 0);
     }
 
+    if (u->has_branch && u->branch_target) {
+        GtkWidget *btn = make_branch_bubble(u);
+        GtkWidget *lbl = gtk_label_new(u->branch_name);
+
+        u->branch_label = lbl;
+        gtk_widget_set_halign(lbl, GTK_ALIGN_START);
+        gtk_widget_add_css_class(lbl, "ex-label");
+        gtk_widget_set_visible(lbl, TRUE);
+
+        gtk_fixed_put(GTK_FIXED(fixed), btn, 0, 0);
+        gtk_fixed_put(GTK_FIXED(fixed), lbl, 0, 0);
+    }
+
     ha = gtk_scrolled_window_get_hadjustment(GTK_SCROLLED_WINDOW(scroll));
     va = gtk_scrolled_window_get_vadjustment(GTK_SCROLLED_WINDOW(scroll));
     g_signal_connect(ha, "notify::page-size",