Pass rect and matrix by value in geometry functions.

Several things irk me about passing values as const pointers:

* They can be NULL, which is not a valid value.
* They require explicit temporary variables for storage.
* They don't compose easily in a legible manner, requiring
  weird pointer passing semantics where the variable being assigned
  is hidden as an argument in the innermost function call.
* We can't change the value through the pointer, requiring yet more
  local variables to hold copies of the input value.

In the device interface where we pass a matrix to a function, we often
find ourselves making a local copy of the matrix so we can concatenate
other transforms to it. This copying is a lot of unnecessary busywork
that I hope to eventually avoid by laying the groundwork with this
commit.

This is a rather large API change, so I apologize for the inconvenience,
but I hope the end result and gain in legibility will be worth the pain.

6 files changed, 17 insertions, 17 deletions

diff --git a/include/mupdf/pdf/annot.h b/include/mupdf/pdf/annot.h
index bd4e8722..1e9361fd 100644
--- a/include/mupdf/pdf/annot.h
+++ b/include/mupdf/pdf/annot.h
@@ -87,7 +87,7 @@ pdf_annot *pdf_next_annot(fz_context *ctx, pdf_annot *annot);
 /*
 	pdf_bound_annot: Return the rectangle for an annotation on a page.
 */
-fz_rect *pdf_bound_annot(fz_context *ctx, pdf_annot *annot, fz_rect *rect);
+fz_rect pdf_bound_annot(fz_context *ctx, pdf_annot *annot);
 
 /*
 	pdf_annot_type: Return the type of an annotation
@@ -132,7 +132,7 @@ pdf_obj *pdf_load_name_tree(fz_context *ctx, pdf_document *doc, pdf_obj *which);
 int pdf_resolve_link(fz_context *ctx, pdf_document *doc, const char *uri, float *xp, float *yp);
 fz_link *pdf_load_link_annots(fz_context *ctx, pdf_document *, pdf_obj *annots, int pagenum, const fz_matrix *page_ctm);
 
-void pdf_annot_transform(fz_context *ctx, pdf_annot *annot, fz_matrix *annot_ctm);
+fz_matrix pdf_annot_transform(fz_context *ctx, pdf_annot *annot);
 void pdf_load_annots(fz_context *ctx, pdf_page *page, pdf_obj *annots);
 void pdf_update_annot(fz_context *ctx, pdf_annot *annot);
 void pdf_drop_annots(fz_context *ctx, pdf_annot *annot_list);
@@ -160,7 +160,7 @@ int pdf_annot_has_open(fz_context *ctx, pdf_annot *annot);
 int pdf_annot_has_author(fz_context *ctx, pdf_annot *annot);
 
 int pdf_annot_flags(fz_context *ctx, pdf_annot *annot);
-void pdf_annot_rect(fz_context *ctx, pdf_annot *annot, fz_rect *rect);
+fz_rect pdf_annot_rect(fz_context *ctx, pdf_annot *annot);
 float pdf_annot_border(fz_context *ctx, pdf_annot *annot);
 float pdf_annot_opacity(fz_context *ctx, pdf_annot *annot);
 void pdf_annot_color(fz_context *ctx, pdf_annot *annot, int *n, float color[4]);
@@ -178,7 +178,7 @@ int pdf_annot_ink_list_stroke_count(fz_context *ctx, pdf_annot *annot, int i);
 fz_point pdf_annot_ink_list_stroke_vertex(fz_context *ctx, pdf_annot *annot, int i, int k);
 
 void pdf_set_annot_flags(fz_context *ctx, pdf_annot *annot, int flags);
-void pdf_set_annot_rect(fz_context *ctx, pdf_annot *annot, const fz_rect *rect);
+void pdf_set_annot_rect(fz_context *ctx, pdf_annot *annot, fz_rect rect);
 void pdf_set_annot_border(fz_context *ctx, pdf_annot *annot, float width);
 void pdf_set_annot_opacity(fz_context *ctx, pdf_annot *annot, float opacity);
 void pdf_set_annot_color(fz_context *ctx, pdf_annot *annot, int n, const float color[4]);
diff --git a/include/mupdf/pdf/document.h b/include/mupdf/pdf/document.h
index 57e726d3..4ca9a3a8 100644
--- a/include/mupdf/pdf/document.h
+++ b/include/mupdf/pdf/document.h
@@ -822,7 +822,7 @@ fz_device *pdf_page_write(fz_context *ctx, pdf_document *doc, const fz_rect *med
 	contents: The page contents for the new page (typically
 	create by pdf_page_write).
 */
-pdf_obj *pdf_add_page(fz_context *ctx, pdf_document *doc, const fz_rect *mediabox, int rotate, pdf_obj *resources, fz_buffer *contents);
+pdf_obj *pdf_add_page(fz_context *ctx, pdf_document *doc, fz_rect mediabox, int rotate, pdf_obj *resources, fz_buffer *contents);
 
 /*
 	pdf_insert_page: Insert a page previously created by
diff --git a/include/mupdf/pdf/object.h b/include/mupdf/pdf/object.h
index 71a8d9d8..e4a9b313 100644
--- a/include/mupdf/pdf/object.h
+++ b/include/mupdf/pdf/object.h
@@ -23,8 +23,8 @@ pdf_obj *pdf_new_text_string(fz_context *ctx, const char *s);
 pdf_obj *pdf_new_indirect(fz_context *ctx, pdf_document *doc, int num, int gen);
 pdf_obj *pdf_new_array(fz_context *ctx, pdf_document *doc, int initialcap);
 pdf_obj *pdf_new_dict(fz_context *ctx, pdf_document *doc, int initialcap);
-pdf_obj *pdf_new_rect(fz_context *ctx, pdf_document *doc, const fz_rect *rect);
-pdf_obj *pdf_new_matrix(fz_context *ctx, pdf_document *doc, const fz_matrix *mtx);
+pdf_obj *pdf_new_rect(fz_context *ctx, pdf_document *doc, fz_rect rect);
+pdf_obj *pdf_new_matrix(fz_context *ctx, pdf_document *doc, fz_matrix mtx);
 pdf_obj *pdf_copy_array(fz_context *ctx, pdf_obj *array);
 pdf_obj *pdf_copy_dict(fz_context *ctx, pdf_obj *dict);
 pdf_obj *pdf_deep_copy_obj(fz_context *ctx, pdf_obj *obj);
@@ -127,8 +127,8 @@ void pdf_dict_put_real(fz_context *ctx, pdf_obj *dict, pdf_obj *key, double x);
 void pdf_dict_put_name(fz_context *ctx, pdf_obj *dict, pdf_obj *key, const char *x);
 void pdf_dict_put_string(fz_context *ctx, pdf_obj *dict, pdf_obj *key, const char *x, size_t n);
 void pdf_dict_put_text_string(fz_context *ctx, pdf_obj *dict, pdf_obj *key, const char *x);
-void pdf_dict_put_rect(fz_context *ctx, pdf_obj *dict, pdf_obj *key, const fz_rect *x);
-void pdf_dict_put_matrix(fz_context *ctx, pdf_obj *dict, pdf_obj *key, const fz_matrix *x);
+void pdf_dict_put_rect(fz_context *ctx, pdf_obj *dict, pdf_obj *key, fz_rect x);
+void pdf_dict_put_matrix(fz_context *ctx, pdf_obj *dict, pdf_obj *key, fz_matrix x);
 pdf_obj *pdf_dict_put_array(fz_context *ctx, pdf_obj *dict, pdf_obj *key, int initial);
 pdf_obj *pdf_dict_put_dict(fz_context *ctx, pdf_obj *dict, pdf_obj *key, int initial);
 
@@ -178,8 +178,8 @@ char *pdf_new_utf8_from_pdf_string_obj(fz_context *ctx, pdf_obj *src);
 char *pdf_new_utf8_from_pdf_stream_obj(fz_context *ctx, pdf_obj *src);
 char *pdf_load_stream_or_string_as_utf8(fz_context *ctx, pdf_obj *src);
 
-fz_rect *pdf_to_rect(fz_context *ctx, pdf_obj *array, fz_rect *rect);
-fz_matrix *pdf_to_matrix(fz_context *ctx, pdf_obj *array, fz_matrix *mat);
+fz_rect pdf_to_rect(fz_context *ctx, pdf_obj *array);
+fz_matrix pdf_to_matrix(fz_context *ctx, pdf_obj *array);
 
 pdf_document *pdf_get_indirect_document(fz_context *ctx, pdf_obj *obj);
 pdf_document *pdf_get_bound_document(fz_context *ctx, pdf_obj *obj);
diff --git a/include/mupdf/pdf/page.h b/include/mupdf/pdf/page.h
index bd0cec9d..25043b1d 100644
--- a/include/mupdf/pdf/page.h
+++ b/include/mupdf/pdf/page.h
@@ -58,7 +58,7 @@ fz_link *pdf_load_links(fz_context *ctx, pdf_page *page);
 	exists (visible area after cropping), otherwise the media box will
 	be used (possibly including printing marks).
 */
-fz_rect *pdf_bound_page(fz_context *ctx, pdf_page *page, fz_rect *);
+fz_rect pdf_bound_page(fz_context *ctx, pdf_page *page);
 
 /*
 	pdf_run_page: Interpret a loaded page and render it on a device.
diff --git a/include/mupdf/pdf/resource.h b/include/mupdf/pdf/resource.h
index b6a2a4b5..d8968996 100644
--- a/include/mupdf/pdf/resource.h
+++ b/include/mupdf/pdf/resource.h
@@ -79,12 +79,12 @@ void pdf_drop_pattern(fz_context *ctx, pdf_pattern *pat);
  * XObject
  */
 
-pdf_obj *pdf_new_xobject(fz_context *ctx, pdf_document *doc, const fz_rect *bbox, const fz_matrix *mat, pdf_obj *res, fz_buffer *buffer);
-void pdf_update_xobject(fz_context *ctx, pdf_document *doc, pdf_obj *xobj, const fz_rect *bbox, const fz_matrix *mat, pdf_obj *res, fz_buffer *buffer);
+pdf_obj *pdf_new_xobject(fz_context *ctx, pdf_document *doc, fz_rect bbox, fz_matrix matrix, pdf_obj *res, fz_buffer *buffer);
+void pdf_update_xobject(fz_context *ctx, pdf_document *doc, pdf_obj *xobj, fz_rect bbox, fz_matrix mat, pdf_obj *res, fz_buffer *buffer);
 
 pdf_obj *pdf_xobject_resources(fz_context *ctx, pdf_obj *xobj);
-fz_rect *pdf_xobject_bbox(fz_context *ctx, pdf_obj *xobj, fz_rect *bbox);
-fz_matrix *pdf_xobject_matrix(fz_context *ctx, pdf_obj *xobj, fz_matrix *matrix);
+fz_rect pdf_xobject_bbox(fz_context *ctx, pdf_obj *xobj);
+fz_matrix pdf_xobject_matrix(fz_context *ctx, pdf_obj *xobj);
 int pdf_xobject_isolated(fz_context *ctx, pdf_obj *xobj);
 int pdf_xobject_knockout(fz_context *ctx, pdf_obj *xobj);
 int pdf_xobject_transparency(fz_context *ctx, pdf_obj *xobj);
diff --git a/include/mupdf/pdf/widget.h b/include/mupdf/pdf/widget.h
index 04c9f887..7e2ae591 100644
--- a/include/mupdf/pdf/widget.h
+++ b/include/mupdf/pdf/widget.h
@@ -65,7 +65,7 @@ int pdf_widget_type(fz_context *ctx, pdf_widget *widget);
 /*
 	pdf_bound_widget: get the bounding box of a widget.
 */
-fz_rect *pdf_bound_widget(fz_context *ctx, pdf_widget *widget, fz_rect *);
+fz_rect pdf_bound_widget(fz_context *ctx, pdf_widget *widget);
 
 /*
 	pdf_text_widget_text: Get the text currently displayed in