From c401151541c3265395ee158b665940c51471bb3b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Elena=20Torr=C3=B3?= <elenatorro@gmail.com>
Date: Mon, 19 Oct 2026 12:07:51 +0200
Subject: [PATCH] :bug: Fix mask group drop shadow in PDF export (#12362)

---
 render-wasm/src/render/pdf.rs    |  1 +
 render-wasm/src/render/vector.rs | 73 +++++++++++++++++++-------------
 2 files changed, 44 insertions(+), 30 deletions(-)

diff --git a/render-wasm/src/render/pdf.rs b/render-wasm/src/render/pdf.rs
index c61fef322b..b5b7366509 100644
--- a/render-wasm/src/render/pdf.rs
+++ b/render-wasm/src/render/pdf.rs
@@ -42,6 +42,7 @@ pub fn render_to_pdf(
     let metadata = skia::pdf::Metadata {
         creator: "Penpot".to_string(),
         producer: "Penpot (Skia PDF)".to_string(),
+        raster_dpi: Some(300.0),
         ..Default::default()
     };
 
diff --git a/render-wasm/src/render/vector.rs b/render-wasm/src/render/vector.rs
index 15a8dc0c32..7eddda2b8b 100644
--- a/render-wasm/src/render/vector.rs
+++ b/render-wasm/src/render/vector.rs
@@ -822,34 +822,7 @@ fn render_group(
     let child_opts = opts.for_children_of(element);
 
     if masked {
-        // Mirror the GPU mask: render all children (including the mask shape)
-        // as content, then re-draw the mask silhouette (the group's first child)
-        // with DstIn to clip everything to it.
-        let paint = Paint::default();
-        let subtree_bounds = element.extrect(tree, scale);
-        canvas.save_layer(
-            &skia::canvas::SaveLayerRec::default()
-                .bounds(&subtree_bounds)
-                .paint(&paint),
-        );
-
-        for child_id in &children {
-            render_tree_inner(shared, canvas, child_id, tree, scale, &child_opts)?;
-        }
-
-        if let Some(mask_id) = element.mask_id() {
-            let mut mask_paint = Paint::default();
-            mask_paint.set_blend_mode(skia::BlendMode::DstIn);
-            canvas.save_layer(
-                &skia::canvas::SaveLayerRec::default()
-                    .bounds(&subtree_bounds)
-                    .paint(&mask_paint),
-            );
-            render_tree_inner(shared, canvas, mask_id, tree, scale, &child_opts)?;
-            canvas.restore(); // mask layer
-        }
-
-        canvas.restore(); // composition layer
+        render_masked_children(shared, canvas, element, &children, tree, scale, &child_opts)?;
     } else {
         for child_id in &children {
             render_tree_inner(shared, canvas, child_id, tree, scale, &child_opts)?;
@@ -863,6 +836,42 @@ fn render_group(
     Ok(())
 }
 
+fn render_masked_children(
+    shared: &mut RenderResources,
+    canvas: &Canvas,
+    element: &Shape,
+    children: &[Uuid],
+    tree: ShapesPoolRef,
+    scale: f32,
+    child_opts: &TreeOpts,
+) -> Result<()> {
+    let subtree_bounds = element.extrect(tree, scale);
+    canvas.save_layer(
+        &skia::canvas::SaveLayerRec::default()
+            .bounds(&subtree_bounds)
+            .paint(&Paint::default()),
+    );
+
+    for child_id in children {
+        render_tree_inner(shared, canvas, child_id, tree, scale, child_opts)?;
+    }
+
+    if let Some(mask_id) = element.mask_id() {
+        let mut mask_paint = Paint::default();
+        mask_paint.set_blend_mode(skia::BlendMode::DstIn);
+        canvas.save_layer(
+            &skia::canvas::SaveLayerRec::default()
+                .bounds(&subtree_bounds)
+                .paint(&mask_paint),
+        );
+        render_tree_inner(shared, canvas, mask_id, tree, scale, child_opts)?;
+        canvas.restore(); // mask layer
+    }
+
+    canvas.restore(); // composition layer
+    Ok(())
+}
+
 // ---------------------------------------------------------------------------
 // Frames
 // ---------------------------------------------------------------------------
@@ -991,8 +1000,12 @@ fn render_container_drop_shadows(
 
         let children = children_paint_order(tree, element);
         let child_opts = opts.for_children_of(element);
-        for child_id in &children {
-            render_tree_inner(shared, canvas, child_id, tree, scale, &child_opts)?;
+        if element.is_masked_group() {
+            render_masked_children(shared, canvas, element, &children, tree, scale, &child_opts)?;
+        } else {
+            for child_id in &children {
+                render_tree_inner(shared, canvas, child_id, tree, scale, &child_opts)?;
+            }
         }
 
         canvas.restore();