Fix PDF pattern embedding

The PDF snapshot cow patch was reusing a previously emitted surface
pattern if the surface unique id matched the current surface. This
resulted in incorrect output as the new pattern may have a different
pattern matrix.

This patch fixes the PDF backend to always emit a new pattern but
re-use previously emitted image or metasurface XObjects.

1 files changed, 15 insertions, 6 deletions

diff --git a/src/cairo-pdf-surface-private.h b/src/cairo-pdf-surface-private.h
index e64b78acc..5aedcd051 100644
--- a/src/cairo-pdf-surface-private.h
+++ b/src/cairo-pdf-surface-private.h
@@ -60,19 +60,27 @@ typedef struct _cairo_pdf_group_resources {
     cairo_array_t fonts;
 } cairo_pdf_group_resources_t;
 
-typedef struct _cairo_pdf_pattern_entry {
+typedef struct _cairo_pdf_source_surface_entry {
     cairo_hash_entry_t base;
     unsigned int id;
-    cairo_pdf_resource_t pattern_res;
-    cairo_pdf_resource_t gstate_res;
-} cairo_pdf_pattern_entry_t;
+    cairo_bool_t interpolate;
+    cairo_pdf_resource_t surface_res;
+    int width;
+    int height;
+} cairo_pdf_source_surface_entry_t;
+
+typedef struct _cairo_pdf_source_surface {
+    cairo_surface_t *surface;
+    cairo_pdf_source_surface_entry_t *hash_entry;
+} cairo_pdf_source_surface_t;
 
 typedef struct _cairo_pdf_pattern {
     double width;
     double height;
     cairo_rectangle_int_t extents;
     cairo_pattern_t *pattern;
-    cairo_pdf_pattern_entry_t *hash_entry;
+    cairo_pdf_resource_t pattern_res;
+    cairo_pdf_resource_t gstate_res;
 } cairo_pdf_pattern_t;
 
 typedef enum _cairo_pdf_operation {
@@ -125,7 +133,8 @@ struct _cairo_pdf_surface {
     cairo_array_t rgb_linear_functions;
     cairo_array_t alpha_linear_functions;
     cairo_array_t page_patterns;
-    cairo_hash_table_t *all_patterns;
+    cairo_array_t page_surfaces;
+    cairo_hash_table_t *all_surfaces;
     cairo_array_t smask_groups;
     cairo_array_t knockout_group;