fix(tab): handle H/P chain and same-beat edge cases

- Individual arcs per H/P pair in chains (e.g. 5{h} 7{h} 5 now
  renders separate H and P arcs instead of one collapsed arc)
- Prevent tryExpand from merging slurs with different H/P labels
  (fixes label loss when multiple H/P on same beat share beam direction)
- Guard existing effectSlur blocks to skip H/P notes, keeping legato
  slide rendering unaffected

Author: rafaelsales

packages/alphatab/src/rendering/glyphs/TabBeatContainerGlyph.ts

@@ -56,24 +56,22 @@ export class TabBeatContainerGlyph extends BeatContainerGlyph {
             const tapSlur: TabTieGlyph = new TabTieGlyph(`tab.tie.leftHandTap.${n.id}`, n, n, false);
             this.addTie(tapSlur);
         }
-        // start effect slur on first beat
-        if (n.isEffectSlurOrigin && n.effectSlurDestination) {
+        // H/P arc start-side: create individual arc per hammer-pull pair
+        if (n.isHammerPullOrigin && n.hammerPullDestination) {
+            const dest = n.hammerPullDestination;
+            const slurText = dest.fret >= n.fret ? 'H' : 'P';
             let expanded: boolean = false;
             for (const slur of this._effectSlurs) {
-                if (slur.tryExpand(n, n.effectSlurDestination, false, false)) {
+                if (slur.tryExpand(n, dest, false, false, slurText)) {
                     expanded = true;
                     break;
                 }
             }
             if (!expanded) {
-                let slurText: string | undefined = undefined;
-                if (n.isHammerPullOrigin && n.hammerPullDestination) {
-                    slurText = n.hammerPullDestination.fret >= n.fret ? 'H' : 'P';
-                }
                 const effectSlur: TabSlurGlyph = new TabSlurGlyph(
                     `tab.slur.effect.${n.id}`,
                     n,
-                    n.effectSlurDestination,
+                    dest,
                     false,
                     false,
                     slurText
@@ -82,8 +80,53 @@ export class TabBeatContainerGlyph extends BeatContainerGlyph {
                 this.addTie(effectSlur);
             }
         }
-        // end effect slur on last beat
-        if (n.isEffectSlurDestination && n.effectSlurOrigin) {
+        // H/P arc end-side: for cross-bar rendering
+        if (n.isHammerPullDestination && n.hammerPullOrigin) {
+            const origin = n.hammerPullOrigin;
+            const slurText = n.fret >= origin.fret ? 'H' : 'P';
+            let expanded: boolean = false;
+            for (const slur of this._effectSlurs) {
+                if (slur.tryExpand(origin, n, false, true, slurText)) {
+                    expanded = true;
+                    break;
+                }
+            }
+            if (!expanded) {
+                const effectSlur: TabSlurGlyph = new TabSlurGlyph(
+                    `tab.slur.effect.${origin.id}`,
+                    origin,
+                    n,
+                    false,
+                    true,
+                    slurText
+                );
+                this._effectSlurs.push(effectSlur);
+                this.addTie(effectSlur);
+            }
+        }
+        // start non-H/P effect slur (e.g. legato slide)
+        if (n.isEffectSlurOrigin && n.effectSlurDestination && !n.isHammerPullOrigin) {
+            let expanded: boolean = false;
+            for (const slur of this._effectSlurs) {
+                if (slur.tryExpand(n, n.effectSlurDestination, false, false)) {
+                    expanded = true;
+                    break;
+                }
+            }
+            if (!expanded) {
+                const effectSlur: TabSlurGlyph = new TabSlurGlyph(
+                    `tab.slur.effect.${n.id}`,
+                    n,
+                    n.effectSlurDestination,
+                    false,
+                    false
+                );
+                this._effectSlurs.push(effectSlur);
+                this.addTie(effectSlur);
+            }
+        }
+        // end non-H/P effect slur
+        if (n.isEffectSlurDestination && n.effectSlurOrigin && !n.isHammerPullDestination) {
             let expanded: boolean = false;
             for (const slur of this._effectSlurs) {
                 if (slur.tryExpand(n.effectSlurOrigin, n, false, true)) {

packages/alphatab/src/rendering/glyphs/TabSlurGlyph.ts

@@ -23,7 +23,11 @@ export class TabSlurGlyph extends TabTieGlyph {
         return this._slurText;
     }
 
-    public tryExpand(startNote: Note, endNote: Note, forSlide: boolean, forEnd: boolean): boolean {
+    public tryExpand(startNote: Note, endNote: Note, forSlide: boolean, forEnd: boolean, slurText?: string): boolean {
+        // same label required (when provided)
+        if (slurText !== undefined && this._slurText !== slurText) {
+            return false;
+        }
         // same type required
         if (this._forSlide !== forSlide) {
             return false;