gecko-dev/gfx/thebes/gfxQuartzNativeDrawing.h

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/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef _GFXQUARTZNATIVEDRAWING_H_
#define _GFXQUARTZNATIVEDRAWING_H_
#include "mozilla/Attributes.h"
#include "gfxContext.h"
#include "gfxQuartzSurface.h"
class THEBES_API gfxQuartzNativeDrawing {
public:
/* Create native Quartz drawing for a rectangle bounded by
* nativeRect.
*
* Typical usage looks like:
*
* gfxQuartzNativeDrawing nativeDraw(ctx, nativeRect);
* CGContextRef cgContext = nativeDraw.BeginNativeDrawing();
* if (!cgContext)
* return NS_ERROR_FAILURE;
*
* ... call Quartz operations on CGContextRef to draw to nativeRect ...
*
* nativeDraw.EndNativeDrawing();
*
* aNativeRect is the size of the surface (in Quartz/Cocoa points) that
* will be created _if_ the gfxQuartzNativeDrawing decides to create a new
* surface and CGContext for its drawing operations, which it then
* composites into the target gfxContext.
*
* (Note that aNativeRect will be ignored if the gfxQuartzNativeDrawing
* uses the target gfxContext directly.)
*
* The optional aBackingScale parameter is a scaling factor that will be
* applied when creating and rendering into such a temporary surface.
*/
gfxQuartzNativeDrawing(gfxContext *ctx,
const gfxRect& aNativeRect,
gfxFloat aBackingScale = 1.0f);
/* Returns a CGContextRef which may be used for native drawing. This
* CGContextRef is valid until EndNativeDrawing is called; if it is used
* for drawing after that time, the result is undefined. */
CGContextRef BeginNativeDrawing();
/* Marks the end of native drawing */
void EndNativeDrawing();
private:
// don't allow copying via construction or assignment
gfxQuartzNativeDrawing(const gfxQuartzNativeDrawing&) MOZ_DELETE;
const gfxQuartzNativeDrawing& operator=(const gfxQuartzNativeDrawing&) MOZ_DELETE;
// Final destination context
nsRefPtr<gfxContext> mContext;
// context that draws to mQuartzSurface; can be different from mContext
// if mContext is not drawing to Quartz
nsRefPtr<gfxContext> mSurfaceContext;
gfxRect mNativeRect;
gfxFloat mBackingScale;
// saved state
nsRefPtr<gfxQuartzSurface> mQuartzSurface;
CGContextRef mCGContext;
};
#endif