1 : /* -*- Mode: C++; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2 : /* ***** BEGIN LICENSE BLOCK *****
3 : * Version: MPL 1.1/GPL 2.0/LGPL 2.1
4 : *
5 : * The contents of this file are subject to the Mozilla Public License Version
6 : * 1.1 (the "License"); you may not use this file except in compliance with
7 : * the License. You may obtain a copy of the License at
8 : * http://www.mozilla.org/MPL/
9 : *
10 : * Software distributed under the License is distributed on an "AS IS" basis,
11 : * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
12 : * for the specific language governing rights and limitations under the
13 : * License.
14 : *
15 : * The Original Code is thebes gfx
16 : *
17 : * The Initial Developer of the Original Code is
18 : * mozilla.org.
19 : * Portions created by the Initial Developer are Copyright (C) 2005
20 : * the Initial Developer. All Rights Reserved.
21 : *
22 : * Contributor(s):
23 : * Vladimir Vukicevic <vladimir@pobox.com>
24 : * Stuart Parmenter <pavlov@pavlov.net>
25 : *
26 : * Alternatively, the contents of this file may be used under the terms of
27 : * either the GNU General Public License Version 2 or later (the "GPL"), or
28 : * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
29 : * in which case the provisions of the GPL or the LGPL are applicable instead
30 : * of those above. If you wish to allow use of your version of this file only
31 : * under the terms of either the GPL or the LGPL, and not to allow others to
32 : * use your version of this file under the terms of the MPL, indicate your
33 : * decision by deleting the provisions above and replace them with the notice
34 : * and other provisions required by the GPL or the LGPL. If you do not delete
35 : * the provisions above, a recipient may use your version of this file under
36 : * the terms of any one of the MPL, the GPL or the LGPL.
37 : *
38 : * ***** END LICENSE BLOCK ***** */
39 :
40 : #ifndef _NS_DEVICECONTEXT_H_
41 : #define _NS_DEVICECONTEXT_H_
42 :
43 : #include "nsCOMPtr.h"
44 : #include "nsIDeviceContextSpec.h"
45 : #include "nsIScreenManager.h"
46 : #include "nsIWidget.h"
47 : #include "nsCoord.h"
48 : #include "gfxContext.h"
49 :
50 : class nsIAtom;
51 : class nsFontCache;
52 : class gfxUserFontSet;
53 :
54 : class nsDeviceContext
55 : {
56 : public:
57 : nsDeviceContext();
58 : ~nsDeviceContext();
59 :
60 0 : NS_INLINE_DECL_REFCOUNTING(nsDeviceContext)
61 :
62 : /**
63 : * Initialize the device context from a widget
64 : * @param aWidget a widget to initialize the device context from
65 : * @return error status
66 : */
67 : nsresult Init(nsIWidget *aWidget);
68 :
69 : /**
70 : * Initialize the device context from a device context spec
71 : * @param aDevSpec the specification of the printing device
72 : * @return error status
73 : */
74 : nsresult InitForPrinting(nsIDeviceContextSpec *aDevSpec);
75 :
76 : /**
77 : * Create a rendering context and initialize it. Only call this
78 : * method on device contexts that were initialized for printing.
79 : * @param aContext out parameter for new rendering context
80 : * @return error status
81 : */
82 : nsresult CreateRenderingContext(nsRenderingContext *&aContext);
83 :
84 : /**
85 : * Gets the number of app units in one CSS pixel; this number is global,
86 : * not unique to each device context.
87 : */
88 0 : static PRInt32 AppUnitsPerCSSPixel() { return 60; }
89 :
90 : /**
91 : * Gets the number of app units in one device pixel; this number
92 : * is usually a factor of AppUnitsPerCSSPixel(), although that is
93 : * not guaranteed.
94 : */
95 0 : PRUint32 AppUnitsPerDevPixel() const { return mAppUnitsPerDevPixel; }
96 :
97 : /**
98 : * Convert device pixels which is used for gfx/thebes to nearest
99 : * (rounded) app units
100 : */
101 0 : nscoord GfxUnitsToAppUnits(gfxFloat aGfxUnits) const
102 0 : { return nscoord(NS_round(aGfxUnits * AppUnitsPerDevPixel())); }
103 :
104 : /**
105 : * Convert app units to device pixels which is used for gfx/thebes.
106 : */
107 0 : gfxFloat AppUnitsToGfxUnits(nscoord aAppUnits) const
108 0 : { return gfxFloat(aAppUnits) / AppUnitsPerDevPixel(); }
109 :
110 : /**
111 : * Gets the number of app units in one physical inch; this is the
112 : * device's DPI times AppUnitsPerDevPixel().
113 : */
114 0 : PRInt32 AppUnitsPerPhysicalInch() const
115 0 : { return mAppUnitsPerPhysicalInch; }
116 :
117 : /**
118 : * Gets the number of app units in one CSS inch; this is
119 : * 96 times AppUnitsPerCSSPixel.
120 : */
121 0 : static PRInt32 AppUnitsPerCSSInch() { return 96 * AppUnitsPerCSSPixel(); }
122 :
123 : /**
124 : * Get the unscaled ratio of app units to dev pixels; useful if something
125 : * needs to be converted from to unscaled pixels
126 : */
127 0 : PRInt32 UnscaledAppUnitsPerDevPixel() const
128 0 : { return mAppUnitsPerDevNotScaledPixel; }
129 :
130 : /**
131 : * Get the nsFontMetrics that describe the properties of
132 : * an nsFont.
133 : * @param aFont font description to obtain metrics for
134 : * @param aLanguage the language of the document
135 : * @param aMetrics out parameter for font metrics
136 : * @param aUserFontSet user font set
137 : * @return error status
138 : */
139 : nsresult GetMetricsFor(const nsFont& aFont, nsIAtom* aLanguage,
140 : gfxUserFontSet* aUserFontSet,
141 : nsFontMetrics*& aMetrics);
142 :
143 : /**
144 : * Notification when a font metrics instance created for this device is
145 : * about to be deleted
146 : */
147 : nsresult FontMetricsDeleted(const nsFontMetrics* aFontMetrics);
148 :
149 : /**
150 : * Attempt to free up resources by flushing out any fonts no longer
151 : * referenced by anything other than the font cache itself.
152 : * @return error status
153 : */
154 : nsresult FlushFontCache();
155 :
156 : /**
157 : * Return the bit depth of the device.
158 : */
159 : nsresult GetDepth(PRUint32& aDepth);
160 :
161 : /**
162 : * Get the size of the displayable area of the output device
163 : * in app units.
164 : * @param aWidth out parameter for width
165 : * @param aHeight out parameter for height
166 : * @return error status
167 : */
168 : nsresult GetDeviceSurfaceDimensions(nscoord& aWidth, nscoord& aHeight);
169 :
170 : /**
171 : * Get the size of the content area of the output device in app
172 : * units. This corresponds on a screen device, for instance, to
173 : * the entire screen.
174 : * @param aRect out parameter for full rect. Position (x,y) will
175 : * be (0,0) or relative to the primary monitor if
176 : * this is not the primary.
177 : * @return error status
178 : */
179 : nsresult GetRect(nsRect& aRect);
180 :
181 : /**
182 : * Get the size of the content area of the output device in app
183 : * units. This corresponds on a screen device, for instance, to
184 : * the area reported by GetDeviceSurfaceDimensions, minus the
185 : * taskbar (Windows) or menubar (Macintosh).
186 : * @param aRect out parameter for client rect. Position (x,y) will
187 : * be (0,0) adjusted for any upper/left non-client
188 : * space if present or relative to the primary
189 : * monitor if this is not the primary.
190 : * @return error status
191 : */
192 : nsresult GetClientRect(nsRect& aRect);
193 :
194 : /**
195 : * Inform the output device that output of a document is beginning
196 : * Used for print related device contexts. Must be matched 1:1 with
197 : * EndDocument() or AbortDocument().
198 : *
199 : * @param aTitle - title of Document
200 : * @param aPrintToFileName - name of file to print to, if NULL
201 : * then don't print to file
202 : * @param aStartPage - starting page number (must be greater than zero)
203 : * @param aEndPage - ending page number (must be less than or
204 : * equal to number of pages)
205 : *
206 : * @return error status
207 : */
208 : nsresult BeginDocument(PRUnichar *aTitle,
209 : PRUnichar *aPrintToFileName,
210 : PRInt32 aStartPage,
211 : PRInt32 aEndPage);
212 :
213 : /**
214 : * Inform the output device that output of a document is ending.
215 : * Used for print related device contexts. Must be matched 1:1 with
216 : * BeginDocument()
217 : * @return error status
218 : */
219 : nsresult EndDocument();
220 :
221 : /**
222 : * Inform the output device that output of a document is being aborted.
223 : * Must be matched 1:1 with BeginDocument()
224 : * @return error status
225 : */
226 : nsresult AbortDocument();
227 :
228 : /**
229 : * Inform the output device that output of a page is beginning
230 : * Used for print related device contexts. Must be matched 1:1 with
231 : * EndPage() and within a BeginDocument()/EndDocument() pair.
232 : * @return error status
233 : */
234 : nsresult BeginPage();
235 :
236 : /**
237 : * Inform the output device that output of a page is ending
238 : * Used for print related device contexts. Must be matched 1:1 with
239 : * BeginPage() and within a BeginDocument()/EndDocument() pair.
240 : * @return error status
241 : */
242 : nsresult EndPage();
243 :
244 : /**
245 : * Check to see if the DPI has changed
246 : * @return whether there was actually a change in the DPI (whether
247 : * AppUnitsPerDevPixel() or AppUnitsPerPhysicalInch()
248 : * changed)
249 : */
250 : bool CheckDPIChange();
251 :
252 : /**
253 : * Set the pixel scaling factor: all lengths are multiplied by this factor
254 : * when we convert them to device pixels. Returns whether the ratio of
255 : * app units to dev pixels changed because of the scale factor.
256 : */
257 : bool SetPixelScale(float aScale);
258 :
259 : /**
260 : * True if this device context was created for printing.
261 : */
262 : bool IsPrinterSurface();
263 :
264 : protected:
265 : void SetDPI();
266 : void ComputeClientRectUsingScreen(nsRect *outRect);
267 : void ComputeFullAreaUsingScreen(nsRect *outRect);
268 : void FindScreen(nsIScreen **outScreen);
269 : void CalcPrintingSize();
270 : void UpdateScaledAppUnits();
271 :
272 : nscoord mWidth;
273 : nscoord mHeight;
274 : PRUint32 mDepth;
275 : PRUint32 mAppUnitsPerDevPixel;
276 : PRInt32 mAppUnitsPerDevNotScaledPixel;
277 : PRInt32 mAppUnitsPerPhysicalInch;
278 : float mPixelScale;
279 : float mPrintingScale;
280 :
281 : nsFontCache* mFontCache;
282 : nsCOMPtr<nsIWidget> mWidget;
283 : nsCOMPtr<nsIScreenManager> mScreenManager;
284 : nsCOMPtr<nsIDeviceContextSpec> mDeviceContextSpec;
285 : nsRefPtr<gfxASurface> mPrintingSurface;
286 : };
287 :
288 : #endif /* _NS_DEVICECONTEXT_H_ */
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