Session 18: Prestige Progress Bar (live visual progress toward next Stellar Essence)

js/prestigeUI.js

@@ -115,6 +115,11 @@ const PrestigeUI = {
             nextEl.textContent = nextEssence;
         }
 
+        // Prestige progress bar: how far total stardust is toward the next
+        // Stellar Essence level. essence(e) = floor(sqrt(totalStardust/1e6)),
+        // so tier e needs e^2*1M stardust and tier (e+1) needs (e+1)^2*1M.
+        this.updatePrestigeProgress();
+
         // Update prestige button state
         const prestigeBtn = document.getElementById('prestige-btn');
         if (prestigeBtn) {
@@ -134,6 +139,35 @@ const PrestigeUI = {
         this.updateBuyMaxPrestigeButton();
     },
 
+    /**
+     * Update the prestige progress bar showing how close total stardust is to
+     * earning the next Stellar Essence. essence level e = floor(sqrt(totalStardust/1e6)),
+     * so tier e begins at e^2*1M and tier (e+1) begins at (e+1)^2*1M; the bar
+     * fills linearly across that tier's stardust range and resets to 0% exactly
+     * when a new essence level is reached. Read-only: mutates only DOM.
+     */
+    updatePrestigeProgress() {
+        const totalStardust = Game.state.totalStardust || 0;
+        const e = Math.floor(Math.sqrt(totalStardust / 1e6));
+        const tierFloor = e * e * 1e6;
+        const tierCeil = (e + 1) * (e + 1) * 1e6;
+        const progress = Math.min(1, Math.max(0, (totalStardust - tierFloor) / (tierCeil - tierFloor)));
+
+        const fillEl = document.getElementById('prestige-progress-fill');
+        if (fillEl) {
+            const pct = Math.round(progress * 100);
+            fillEl.style.width = `${pct}%`;
+            // Only apply the pulsing glow while there is progress to show, so a
+            // freshly-emptied bar (e.g. right after prestige) sits still.
+            fillEl.classList.toggle('filling', pct > 0 && pct < 100);
+        }
+
+        const pctLabel = document.getElementById('prestige-progress-pct');
+        if (pctLabel) {
+            pctLabel.textContent = `${Math.round(progress * 100)}%`;
+        }
+    },
+
     /**
      * Show/hide and enable/disable the "Buy Max" prestige-upgrades button
      * depending on whether at least one unowned, requirement-met prestige