skia2/include/core/SkDocument.h
Hal Canary d18d7bd294 SK_SUPPORT_LEGACY_DOCUMENT_FACTORY: clean up part 2/2
Change-Id: Ibab2f420c779e0307f4df214f229609b377acf29
Reviewed-on: https://skia-review.googlesource.com/c/156369
Reviewed-by: Hal Canary <halcanary@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
2018-10-04 20:00:24 +00:00

92 lines
2.5 KiB
C++

/*
* 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 "SkRefCnt.h"
#include "SkScalar.h"
class SkCanvas;
class SkWStream;
struct SkRect;
/** SK_ScalarDefaultDPI is 72 dots per inch. */
static constexpr SkScalar SK_ScalarDefaultRasterDPI = 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 SK_API SkDocument : public SkRefCnt {
public:
/**
* 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 = nullptr);
/**
* Call endPage() when the content for the current page has been drawn
* (into the canvas returned by beginPage()). After this call the canvas
* returned by beginPage() will be out-of-scope.
*/
void endPage();
/**
* Call close() when all pages have been drawn. This will close the file
* or stream holding the document's contents. After close() the document
* can no longer add new pages. Deleting the document will automatically
* call close() if need be.
*/
void close();
/**
* Call abort() to stop producing the document immediately.
* The stream output must be ignored, and should not be trusted.
*/
void abort();
protected:
SkDocument(SkWStream*);
// note: subclasses must call close() in their destructor, as the base class
// cannot do this for them.
virtual ~SkDocument();
virtual SkCanvas* onBeginPage(SkScalar width, SkScalar height) = 0;
virtual void onEndPage() = 0;
virtual void onClose(SkWStream*) = 0;
virtual void onAbort() = 0;
// Allows subclasses to write to the stream as pages are written.
SkWStream* getStream() { return fStream; }
enum State {
kBetweenPages_State,
kInPage_State,
kClosed_State
};
State getState() const { return fState; }
private:
SkWStream* fStream;
State fState;
typedef SkRefCnt INHERITED;
};
#endif