Preserve SVG picture fallbacks in the Presentation model

crates/drawingml/src/read.rs

@@ -166,6 +166,12 @@ pub fn blip_fill(src: &mut dyn Source, bf: &El) -> Option<PictureFill> {
     {
         pf.artistic = Some(crate::style::Artistic { effect, original });
     }
+    pf.svg = blip.and_then(|b| b.child(Local("extLst"))).and_then(|extensions| {
+        extensions
+            .elements()
+            .filter(|extension| extension.local() == "ext" && extension.attr_local("uri") == Some("{96DAC541-7B7A-43D3-8B79-37D633B846F1}"))
+            .find_map(|extension| extension.child(Local("svgBlip")).and_then(|svg| media_ref(src, svg)))
+    });
     if let Some(b) = blip {
         for e in b.elements() {
             match e.local() {

crates/drawingml/src/style.rs

@@ -184,6 +184,9 @@ impl Default for PictureMode {
 #[serde(default, rename_all = "camelCase")]
 pub struct PictureFill {
     pub media: MediaId,
+    /// Optional vector SVG version of `media`; the regular media remains the bitmap fallback.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub svg: Option<MediaId>,
     /// Source crop as fractions of the image (left, top, right, bottom); negative values pad.
     pub crop: [f64; 4],
     pub mode: PictureMode,

crates/drawingml/src/write.rs

@@ -107,6 +107,7 @@ pub fn blip_fill(w: &mut Writer, out: &mut dyn Sink, tag: &str, pf: &PictureFill
     w.tag(tag).attr("rotWithShape", if pf.upright { "0" } else { "1" }).open();
     let adj = &pf.adjust;
     let has_kids = pf.alpha.is_some()
+        || pf.svg.is_some()
         || adj.brightness != 0.0
         || adj.contrast != 0.0
         || adj.grayscale
@@ -168,6 +169,13 @@ pub fn blip_fill(w: &mut Writer, out: &mut dyn Sink, tag: &str, pf: &PictureFill
             w.close();
             w.close();
         }
+        if let Some(svg) = pf.svg.and_then(|id| out.media_rel(id, "image")) {
+            w.open("a:extLst", &[]);
+            w.tag("a:ext").attr("uri", "{96DAC541-7B7A-43D3-8B79-37D633B846F1}").open();
+            w.tag("asvg:svgBlip").attr("xmlns:asvg", "http://schemas.microsoft.com/office/drawing/2016/SVG/main").attr("r:embed", &svg).empty();
+            w.close();
+            w.close();
+        }
         w.close();
     } else {
         w.tag("a:blip").list(a).empty();