Add DPI stettings to SkDocument::CreatePDF(). Tests will be added in a future cl, once DPI will be …

include/core/SkDocument.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkDocument_DEFINED
 #define SkDocument_DEFINED
 
 #include "SkBitmap.h"
 #include "SkPicture.h"
 #include "SkRect.h"
 #include "SkRefCnt.h"
 
 class SkCanvas;
 class SkWStream;
 
+/** SK_ScalarDefaultDPI is 72 DPI.
+*/
+#define SK_ScalarDefaultDPI           SkFloatToScalar(72.0f)
+
 /**
  *  High-level API for creating a document-based canvas. To use..
  *
  *  1. Create a document, specifying a stream to store the output.
  *  2. For each "page" of content:
  *      a. canvas = doc->beginPage(...)
  *      b. draw_my_content(canvas);
  *      c. doc->endPage();
  *  3. Close the document with doc->close().
  */
 class SkDocument : public SkRefCnt {
 public:
     SK_DECLARE_INST_COUNT(SkDocument)
 
     /**
      *  Create a PDF-backed document, writing the results into a file.
      *  If there is an error trying to create the doc, returns NULL.
      *  encoder sets the DCTEncoder for images, to encode a bitmap
      *    as JPEG (DCT).

[reed1, 2013/10/21 13:10:24]

What does DPI mean to the client when they draw into this Document? Does it
affect the coordinates they should pass in? Does it affect internal
optimizations? Does it indicated something about the presumed target when the
Document gets "played" back?

[edisonn, 2013/10/21 14:40:58]

No
 Does it affect internal
it could, the images might be smaller or bigger, we might change the way we
encode the image (no ecoding, zip, jpeg), but I am not sure I should put this in
the comment, as the encoder controlls this
Does it indicated something about the presumed target when the
Not much, but if a ridiculous high DPI is used, the play back will be slow or
will fail because memory can't be allocated

added comment

      */
     static SkDocument* CreatePDF(const char filename[],
-                                 SkPicture::EncodeBitmap encoder = NULL);
+                                 SkPicture::EncodeBitmap encoder = NULL,
+                                 SkScalar dpi = SK_ScalarDefaultDPI);
 
     /**
      *  Create a PDF-backed document, writing the results into a stream.
      *  If there is an error trying to create the doc, returns NULL.
      *
      *  The document may write to the stream at anytime during its lifetime,
      *  until either close() is called or the document is deleted. Once close()
      *  has been called, and all of the data has been written to the stream,
      *  if there is a Done proc provided, it will be called with the stream.
      *  The proc can delete the stream, or whatever it needs to do.
      *  encoder sets the DCTEncoder for images, to encode a bitmap
      *    as JPEG (DCT).
      */
     static SkDocument* CreatePDF(SkWStream*, void (*Done)(SkWStream*) = NULL,
-                                 SkPicture::EncodeBitmap encoder = NULL);
+                                 SkPicture::EncodeBitmap encoder = NULL,
+                                 SkScalar dpi = SK_ScalarDefaultDPI);
 
     /**
      *  Begin a new page for the document, returning the canvas that will draw
      *  into the page. The document owns this canvas, and it will go out of
      *  scope when endPage() or close() is called, or the document is deleted.
      */
     SkCanvas* beginPage(SkScalar width, SkScalar height,
                         const SkRect* content = NULL);
 
     /**
@@ skipping 39 matching lines @@
 
 private:
     SkWStream* fStream;
     void       (*fDoneProc)(SkWStream*);
     State      fState;
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif