michael@0: /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef _GFXWINDOWSNATIVEDRAWING_H_
michael@0: #define _GFXWINDOWSNATIVEDRAWING_H_
michael@0: 
michael@0: #include <windows.h>
michael@0: 
michael@0: #include "gfxContext.h"
michael@0: #include "gfxWindowsSurface.h"
michael@0: 
michael@0: class gfxWindowsNativeDrawing {
michael@0: public:
michael@0: 
michael@0:     /* Flags for notifying this class what kind of operations the native
michael@0:      * drawing supports
michael@0:      */
michael@0: 
michael@0:     enum {
michael@0:         /* Whether the native drawing can draw to a surface of content COLOR_ALPHA */
michael@0:         CAN_DRAW_TO_COLOR_ALPHA    = 1 << 0,
michael@0:         CANNOT_DRAW_TO_COLOR_ALPHA = 0 << 0,
michael@0: 
michael@0:         /* Whether the native drawing can be scaled using SetWorldTransform */
michael@0:         CAN_AXIS_ALIGNED_SCALE     = 1 << 1,
michael@0:         CANNOT_AXIS_ALIGNED_SCALE  = 0 << 1,
michael@0: 
michael@0:         /* Whether the native drawing can be both scaled and rotated arbitrarily using SetWorldTransform */
michael@0:         CAN_COMPLEX_TRANSFORM      = 1 << 2,
michael@0:         CANNOT_COMPLEX_TRANSFORM   = 0 << 2,
michael@0: 
michael@0:         /* If we have to do transforms with cairo, should we use nearest-neighbour filtering? */
michael@0:         DO_NEAREST_NEIGHBOR_FILTERING = 1 << 3,
michael@0:         DO_BILINEAR_FILTERING         = 0 << 3
michael@0:     };
michael@0: 
michael@0:     /* Create native win32 drawing for a rectangle bounded by
michael@0:      * nativeRect.
michael@0:      *
michael@0:      * Typical usage looks like:
michael@0:      *
michael@0:      *   gfxWindowsNativeDrawing nativeDraw(ctx, destGfxRect, capabilities);
michael@0:      *   do {
michael@0:      *     HDC dc = nativeDraw.BeginNativeDrawing();
michael@0:      *     if (!dc)
michael@0:      *       return NS_ERROR_FAILURE;
michael@0:      *
michael@0:      *     RECT winRect;
michael@0:      *     nativeDraw.TransformToNativeRect(rect, winRect);
michael@0:      *
michael@0:      *       ... call win32 operations on HDC to draw to winRect ...
michael@0:      *
michael@0:      *     nativeDraw.EndNativeDrawing();
michael@0:      *   } while (nativeDraw.ShouldRenderAgain());
michael@0:      *   nativeDraw.PaintToContext();
michael@0:      */
michael@0:     gfxWindowsNativeDrawing(gfxContext *ctx,
michael@0:                             const gfxRect& nativeRect,
michael@0:                             uint32_t nativeDrawFlags = CANNOT_DRAW_TO_COLOR_ALPHA |
michael@0:                                                        CANNOT_AXIS_ALIGNED_SCALE |
michael@0:                                                        CANNOT_COMPLEX_TRANSFORM |
michael@0:                                                        DO_BILINEAR_FILTERING);
michael@0: 
michael@0:     /* Returns a HDC which may be used for native drawing.  This HDC is valid
michael@0:      * until EndNativeDrawing is called; if it is used for drawing after that time,
michael@0:      * the result is undefined. */
michael@0:     HDC BeginNativeDrawing();
michael@0: 
michael@0:     /* Transform the native rect into something valid for rendering
michael@0:      * to the HDC.  This may or may not change RECT, depending on
michael@0:      * whether SetWorldTransform is used or not. */
michael@0:     void TransformToNativeRect(const gfxRect& r, RECT& rout);
michael@0: 
michael@0:     /* Marks the end of native drawing */
michael@0:     void EndNativeDrawing();
michael@0: 
michael@0:     /* Returns true if the native drawing should be executed again */
michael@0:     bool ShouldRenderAgain();
michael@0: 
michael@0:     /* Returns true if double pass alpha extraction is taking place. */
michael@0:     bool IsDoublePass();
michael@0: 
michael@0:     /* Places the result to the context, if necessary */
michael@0:     void PaintToContext();
michael@0: 
michael@0: private:
michael@0: 
michael@0:     nsRefPtr<gfxContext> mContext;
michael@0:     gfxRect mNativeRect;
michael@0:     uint32_t mNativeDrawFlags;
michael@0: 
michael@0:     // what state the rendering is in
michael@0:     uint8_t mRenderState;
michael@0: 
michael@0:     gfxPoint mDeviceOffset;
michael@0:     nsRefPtr<gfxPattern> mBlackPattern, mWhitePattern;
michael@0: 
michael@0:     enum TransformType {
michael@0:         TRANSLATION_ONLY,
michael@0:         AXIS_ALIGNED_SCALE,
michael@0:         COMPLEX
michael@0:     };
michael@0: 
michael@0:     TransformType mTransformType;
michael@0:     gfxPoint mTranslation;
michael@0:     gfxSize mScale;
michael@0:     XFORM mWorldTransform;
michael@0: 
michael@0:     // saved state
michael@0:     nsRefPtr<gfxWindowsSurface> mWinSurface, mBlackSurface, mWhiteSurface;
michael@0:     HDC mDC;
michael@0:     XFORM mOldWorldTransform;
michael@0:     POINT mOrigViewportOrigin;
michael@0:     gfxIntSize mTempSurfaceSize;
michael@0: };
michael@0: 
michael@0: #endif