widget/nsIDeviceContextSpec.h
author Bob Owen <bobowencode@gmail.com>
Mon, 21 Dec 2015 20:33:13 +0000
changeset 312341 7f8e595885186a88d337da38c800ff0b9950a7e8
parent 178109 5a9badd6db004310b9d1aca5db25ef4c275a4362
child 312343 dedca8fb19b04dc66928bf97f2db6dbdc39253b4
permissions -rw-r--r--
Bug 1156742 Part 7: Refactor nsDeviceContext.cpp to use printing surface for size and nsIDeviceContextSpec for DPI and scale. r=roc These changes are to make using an off screen surface behind our DrawTarget in the child easier. It still creates the real printing surface for some of the calculations, removing this will be required for future tightening of the sandbox.

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 nsIDeviceContextSpec_h___
#define nsIDeviceContextSpec_h___

#include "nsISupports.h"

class nsIWidget;
class nsIPrintSettings;
class gfxASurface;

#define NS_IDEVICE_CONTEXT_SPEC_IID   \
{ 0xf407cfba, 0xbe28, 0x46c9, \
  { 0x8a, 0xba, 0x04, 0x2d, 0xae, 0xbb, 0x4f, 0x23 } }

class nsIDeviceContextSpec : public nsISupports
{
public:
   NS_DECLARE_STATIC_IID_ACCESSOR(NS_IDEVICE_CONTEXT_SPEC_IID)

   /**
    * Initialize the device context spec.
    * @param aWidget         A widget a dialog can be hosted in
    * @param aPrintSettings  Print settings for the print operation
    * @param aIsPrintPreview True if creating Spec for PrintPreview
    * @return NS_OK or a suitable error code.
    */
   NS_IMETHOD Init(nsIWidget *aWidget,
                   nsIPrintSettings* aPrintSettings,
                   bool aIsPrintPreview) = 0;

   NS_IMETHOD GetSurfaceForPrinter(gfxASurface **nativeSurface) = 0;

   /**
    * Override to return something other than the default.
    *
    * @return DPI for printing.
    */
   virtual float GetDPI() { return 72.0f; }

   /**
    * Override to return something other than the default.
    *
    * @return the printing scale to be applied to the context for printing.
    */
   virtual float GetPrintingScale() { return 1.0f;  }

   NS_IMETHOD BeginDocument(const nsAString& aTitle,
                            char16_t*       aPrintToFileName,
                            int32_t          aStartPage,
                            int32_t          aEndPage) = 0;

   NS_IMETHOD EndDocument() = 0;
   NS_IMETHOD BeginPage() = 0;
   NS_IMETHOD EndPage() = 0;
};

NS_DEFINE_STATIC_IID_ACCESSOR(nsIDeviceContextSpec,
                              NS_IDEVICE_CONTEXT_SPEC_IID)
#endif