gfx/thebes/public/gfxWindowsNativeDrawing.h

   1 /* -*- Mode: C++; tab-width: 20; 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 Mozilla Corporation.
  18  * Portions created by the Initial Developer are Copyright (C) 2007
  19  * the Initial Developer. All Rights Reserved.
  20  *
  21  * Contributor(s):
  22  *   Vladimir Vukicevic <vladimir@pobox.com>
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either the GNU General Public License Version 2 or later (the "GPL"), or
  26  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  27  * in which case the provisions of the GPL or the LGPL are applicable instead
  28  * of those above. If you wish to allow use of your version of this file only
  29  * under the terms of either the GPL or the LGPL, and not to allow others to
  30  * use your version of this file under the terms of the MPL, indicate your
  31  * decision by deleting the provisions above and replace them with the notice
  32  * and other provisions required by the GPL or the LGPL. If you do not delete
  33  * the provisions above, a recipient may use your version of this file under
  34  * the terms of any one of the MPL, the GPL or the LGPL.
  35  *
  36  * ***** END LICENSE BLOCK ***** */
  37
  38 #ifndef _GFXWINDOWSNATIVEDRAWING_H_
  39 #define _GFXWINDOWSNATIVEDRAWING_H_
  40
  41 #include <windows.h>
  42
  43 #include "gfxContext.h"
  44 #include "gfxWindowsSurface.h"
  45
  46 class THEBES_API gfxWindowsNativeDrawing {
  47 public:
  48
  49     /* Flags for notifying this class what kind of operations the native
  50      * drawing supports
  51      */
  52
  53     enum {
  54         /* Whether the native drawing can draw to a surface of content COLOR_ALPHA */
  55         CAN_DRAW_TO_COLOR_ALPHA    = 1 << 0,
  56         CANNOT_DRAW_TO_COLOR_ALPHA = 0 << 0,
  57
  58         /* Whether the native drawing can be scaled using SetWorldTransform */
  59         CAN_AXIS_ALIGNED_SCALE     = 1 << 1,
  60         CANNOT_AXIS_ALIGNED_SCALE  = 0 << 1,
  61
  62         /* Whether the native drawing can be both scaled and rotated arbitrarily using SetWorldTransform */
  63         CAN_COMPLEX_TRANSFORM      = 1 << 2,
  64         CANNOT_COMPLEX_TRANSFORM   = 0 << 2,
  65
  66         /* If we have to do transforms with cairo, should we use nearest-neighbour filtering? */
  67         DO_NEAREST_NEIGHBOR_FILTERING = 1 << 3,
  68         DO_BILINEAR_FILTERING         = 0 << 3
  69     };
  70
  71     /* Create native win32 drawing for a rectangle bounded by
  72      * nativeRect.
  73      *
  74      * Typical usage looks like:
  75      *
  76      *   gfxWindowsNativeDrawing nativeDraw(ctx, destGfxRect, capabilities);
  77      *   do {
  78      *     HDC dc = nativeDraw.BeginNativeDrawing();
  79      *     if (!dc)
  80      *       return NS_ERROR_FAILURE;
  81      *
  82      *     RECT winRect;
  83      *     nativeDraw.TransformToNativeRect(rect, winRect);
  84      *
  85      *       ... call win32 operations on HDC to draw to winRect ...
  86      *
  87      *     nativeDraw.EndNativeDrawing();
  88      *   } while (nativeDraw.ShouldRenderAgain());
  89      *   nativeDraw.PaintToContext();
  90      */
  91     gfxWindowsNativeDrawing(gfxContext *ctx,
  92                             const gfxRect& nativeRect,
  93                             PRUint32 nativeDrawFlags = CANNOT_DRAW_TO_COLOR_ALPHA |
  94                                                        CANNOT_AXIS_ALIGNED_SCALE |
  95                                                        CANNOT_COMPLEX_TRANSFORM |
  96                                                        DO_BILINEAR_FILTERING);
  97
  98     /* Returns a HDC which may be used for native drawing.  This HDC is valid
  99      * until EndNativeDrawing is called; if it is used for drawing after that time,
 100      * the result is undefined. */
 101     HDC BeginNativeDrawing();
 102
 103     /* Transform the native rect into something valid for rendering
 104      * to the HDC.  This may or may not change RECT, depending on
 105      * whether SetWorldTransform is used or not. */
 106     void TransformToNativeRect(const gfxRect& r, RECT& rout);
 107
 108     /* Marks the end of native drawing */
 109     void EndNativeDrawing();
 110
 111     /* Returns PR_TRUE if the native drawing should be executed again */
 112     PRBool ShouldRenderAgain();
 113
 114     /* Places the result to the context, if necessary */
 115     void PaintToContext();
 116
 117 private:
 118
 119     nsRefPtr<gfxContext> mContext;
 120     gfxRect mNativeRect;
 121     PRUint32 mNativeDrawFlags;
 122
 123     // what state the rendering is in
 124     PRUint8 mRenderState;
 125
 126     gfxPoint mDeviceOffset;
 127     nsRefPtr<gfxPattern> mBlackPattern, mWhitePattern;
 128
 129     enum TransformType {
 130         TRANSLATION_ONLY,
 131         AXIS_ALIGNED_SCALE,
 132         COMPLEX
 133     };
 134
 135     TransformType mTransformType;
 136     gfxPoint mTranslation;
 137     gfxSize mScale;
 138     XFORM mWorldTransform;
 139
 140     // saved state
 141     nsRefPtr<gfxWindowsSurface> mWinSurface, mBlackSurface, mWhiteSurface;
 142     HDC mDC;
 143     XFORM mOldWorldTransform;
 144     POINT mOrigViewportOrigin;
 145     gfxIntSize mTempSurfaceSize;
 146 };
 147
 148 #endif