Merge pull request #20 from LaurenzV/rust_logo_fix

Preliminary fix for #17

Author: reknih

src/defer.rs

@@ -9,7 +9,7 @@ use std::collections::HashMap;
 use pdf_writer::types::{MaskType, ShadingType};
 use pdf_writer::writers::{ExtGraphicsState, Resources, ShadingPattern};
 use pdf_writer::{Finish, Name, PdfWriter, Rect, Ref};
-use usvg::{NodeKind, Tree};
+use usvg::{NodeKind, Transform, Tree};
 
 use super::{content_stream, form_xobject, Context, CoordToPdf};
 use crate::render::Gradient;
@@ -130,6 +130,9 @@ pub struct PendingGroup {
     /// A transformation matrix to allow for a different coordinate system use
     /// in the object.
     pub matrix: Option<[f32; 6]>,
+    // Contains the transform of the context where the pending group
+    // was in the tree
+    pub transform: Transform,
     /// An SVG ID to a mask that should be applied at the start of the content
     /// stream.
     pub initial_mask: Option<String>,
@@ -236,6 +239,9 @@ pub(crate) fn write_masks(tree: &Tree, writer: &mut PdfWriter, ctx: &mut Context
             ctx.push();
             ctx.initial_mask = gp.initial_mask;
 
+            // Get the context of where the pending group was originally in the tree
+            let old = ctx.c.set_transform(gp.transform);
+
             let content = content_stream(&mask_node, writer, ctx);
 
             let mut group =
@@ -245,6 +251,8 @@ pub(crate) fn write_masks(tree: &Tree, writer: &mut PdfWriter, ctx: &mut Context
                 group.matrix(matrix);
             }
 
+            ctx.c.set_transform(old);
+
             let mut resources = group.resources();
             ctx.pop(&mut resources);
             resources.finish();

src/lib.rs

@@ -563,12 +563,18 @@ fn apply_mask(
 
             apply_mask(mask.mask.as_ref(), mask.rect, pdf_bbox, ctx);
 
-            ctx.pending_groups.insert(mask.id.clone(), PendingGroup {
-                reference,
-                bbox,
-                matrix,
-                initial_mask: mask.mask.clone(),
-            });
+            let context_transform = ctx.c.get_transform();
+
+            ctx.pending_groups.insert(
+                mask.id.clone(),
+                PendingGroup {
+                    reference,
+                    bbox,
+                    matrix,
+                    transform: context_transform,
+                    initial_mask: mask.mask.clone(),
+                },
+            );
 
             Some(reference)
         } else {

src/render.rs

@@ -539,7 +539,6 @@ impl Render for usvg::Group {
         content.save_state();
 
         apply_clip_path(self.clip_path.as_ref(), content, ctx);
-        ctx.c.set_transform(old);
 
         if let Some(reference) = apply_mask(self.mask.as_ref(), bbox, pdf_bbox, ctx) {
             let num = ctx.alloc_gs();
@@ -554,6 +553,8 @@ impl Render for usvg::Group {
                 .push(PendingGS::fill_opacity(self.opacity.value() as f32, num));
         }
 
+        ctx.c.set_transform(old);
+
         content.x_object(Name(name.as_bytes()));
         content.restore_state();
         ctx.pending_xobjects.push((num, group_ref));

src/scale.rs

@@ -171,7 +171,13 @@ impl CoordToPdf {
         old
     }
 
-    pub fn set_transform(&mut self, transform: Transform) {
+    pub fn set_transform(&mut self, transform: Transform) -> Transform {
+        let old = self.transform;
         self.transform = transform;
+        old
+    }
+
+    pub fn get_transform(&self) -> Transform {
+        self.transform
     }
 }