feat: add cli args for PDF/UA-1 standard and to disable tagging

crates/typst-cli/src/args.rs

@@ -246,6 +246,13 @@ pub struct CompileArgs {
     #[arg(long = "pdf-standard", value_delimiter = ',')]
     pub pdf_standard: Vec<PdfStandard>,
 
+    /// By default, even when not producing a `PDF/UA-1` document, a tagged PDF
+    /// document is written to provide a baseline of accessibility. In some
+    /// circumstances (for example when trying to reduce the size of a document)
+    /// it can be desirable to disable tagged PDF.
+    #[arg(long = "disable-pdf-tags")]
+    pub disable_pdf_tags: bool,
+
     /// The PPI (pixels per inch) to use for PNG export.
     #[arg(long = "ppi", default_value_t = 144.0)]
     pub ppi: f32,
@@ -506,6 +513,9 @@ pub enum PdfStandard {
     /// PDF/A-4e.
     #[value(name = "a-4e")]
     A_4e,
+    /// PDF/UA-1.
+    #[value(name = "ua-1")]
+    Ua_1,
 }
 
 display_possible_values!(PdfStandard);

crates/typst-cli/src/compile.rs

@@ -65,6 +65,8 @@ pub struct CompileConfig {
     pub open: Option<Option<String>>,
     /// A list of standards the PDF should conform to.
     pub pdf_standards: PdfStandards,
+    /// Whether to write PDF (accessibility) tags.
+    pub disable_pdf_tags: bool,
     /// A path to write a Makefile rule describing the current compilation.
     pub make_deps: Option<PathBuf>,
     /// The PPI (pixels per inch) to use for PNG export.
@@ -150,6 +152,7 @@ impl CompileConfig {
             output_format,
             pages,
             pdf_standards,
+            disable_pdf_tags: args.disable_pdf_tags,
             creation_timestamp: args.world.creation_timestamp,
             make_deps: args.make_deps.clone(),
             ppi: args.ppi,
@@ -291,6 +294,7 @@ fn export_pdf(document: &PagedDocument, config: &CompileConfig) -> SourceResult<
         timestamp,
         page_ranges: config.pages.clone(),
         standards: config.pdf_standards.clone(),
+        disable_tags: config.disable_pdf_tags,
     };
     let buffer = typst_pdf::pdf(document, &options)?;
     config
@@ -773,6 +777,7 @@ impl From<PdfStandard> for typst_pdf::PdfStandard {
             PdfStandard::A_4 => typst_pdf::PdfStandard::A_4,
             PdfStandard::A_4f => typst_pdf::PdfStandard::A_4f,
             PdfStandard::A_4e => typst_pdf::PdfStandard::A_4e,
+            PdfStandard::Ua_1 => typst_pdf::PdfStandard::Ua_1,
         }
     }
 }

crates/typst-pdf/src/convert.rs

@@ -39,17 +39,14 @@ pub fn convert(
     typst_document: &PagedDocument,
     options: &PdfOptions,
 ) -> SourceResult<Vec<u8>> {
-    // HACK
-    let config = Configuration::new_with_validator(Validator::UA1);
     let settings = SerializeSettings {
-        compress_content_streams: false, // true,
+        compress_content_streams: true,
         no_device_cs: true,
-        ascii_compatible: true, // false,
+        ascii_compatible: false,
         xmp_metadata: true,
         cmyk_profile: None,
-        configuration: config, // options.standards.config,
-        // TODO: allow opting out of tagging PDFs
-        enable_tagging: true,
+        configuration: options.standards.config,
+        enable_tagging: !options.disable_tags,
         render_svg_glyph_fn: render_svg_glyph,
     };
 

crates/typst-pdf/src/lib.rs

@@ -54,6 +54,11 @@ pub struct PdfOptions<'a> {
     pub page_ranges: Option<PageRanges>,
     /// A list of PDF standards that Typst will enforce conformance with.
     pub standards: PdfStandards,
+    /// By default, even when not producing a `PDF/UA-1` document, a tagged PDF
+    /// document is written to provide a baseline of accessibility. In some
+    /// circumstances, for example when trying to reduce the size of a document,
+    /// it can be desirable to disable tagged PDF.
+    pub disable_tags: bool,
 }
 
 /// Encapsulates a list of compatible PDF standards.
@@ -105,6 +110,7 @@ impl PdfStandards {
                 PdfStandard::A_4 => set_validator(Validator::A4)?,
                 PdfStandard::A_4f => set_validator(Validator::A4F)?,
                 PdfStandard::A_4e => set_validator(Validator::A4E)?,
+                PdfStandard::Ua_1 => set_validator(Validator::UA1)?,
             }
         }
 
@@ -188,4 +194,7 @@ pub enum PdfStandard {
     /// PDF/A-4e.
     #[serde(rename = "a-4e")]
     A_4e,
+    /// PDF/UA-1.
+    #[serde(rename = "ua-1")]
+    Ua_1,
 }