/* -*- Mode: C++; tab-width: 20; 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 _GFXWINDOWSNATIVEDRAWING_H_
#define _GFXWINDOWSNATIVEDRAWING_H_
#include <windows.h>
#include "gfxContext.h"
#include "gfxWindowsSurface.h"
class MOZ_STACK_CLASS gfxWindowsNativeDrawing {
public:
/* Flags for notifying this class what kind of operations the native
* drawing supports
*/
enum {
/* Whether the native drawing can draw to a surface of content COLOR_ALPHA
*/
CAN_DRAW_TO_COLOR_ALPHA = 1 << 0,
CANNOT_DRAW_TO_COLOR_ALPHA = 0 << 0,
/* Whether the native drawing can be scaled using SetWorldTransform */
CAN_AXIS_ALIGNED_SCALE = 1 << 1,
CANNOT_AXIS_ALIGNED_SCALE = 0 << 1,
/* Whether the native drawing can be both scaled and rotated arbitrarily
using SetWorldTransform */
CAN_COMPLEX_TRANSFORM = 1 << 2,
CANNOT_COMPLEX_TRANSFORM = 0 << 2,
};
/* Create native win32 drawing for a rectangle bounded by
* nativeRect.
*
* Typical usage looks like:
*
* gfxWindowsNativeDrawing nativeDraw(ctx, destGfxRect, capabilities);
* do {
* HDC dc = nativeDraw.BeginNativeDrawing();
* if (!dc)
* return NS_ERROR_FAILURE;
*
* RECT winRect;
* nativeDraw.TransformToNativeRect(rect, winRect);
*
* ... call win32 operations on HDC to draw to winRect ...
*
* nativeDraw.EndNativeDrawing();
* } while (nativeDraw.ShouldRenderAgain());
* nativeDraw.PaintToContext();
*/
gfxWindowsNativeDrawing(
gfxContext* ctx,
const gfxRect& nativeRect,
uint32_t nativeDrawFlags = CANNOT_DRAW_TO_COLOR_ALPHA |
CANNOT_AXIS_ALIGNED_SCALE |
CANNOT_COMPLEX_TRANSFORM);
/* Returns a HDC which may be used for native drawing. This HDC is valid
* until EndNativeDrawing is called; if it is used for drawing after that
* time, the result is undefined. */
HDC BeginNativeDrawing();
/* Transform the native rect into something valid for rendering
* to the HDC. This may or may not change RECT, depending on
* whether SetWorldTransform is used or not. */
void TransformToNativeRect(
const gfxRect& r, RECT& rout);
/* Marks the end of native drawing */
void EndNativeDrawing();
/* Returns true if the native drawing should be executed again */
bool ShouldRenderAgain();
/* Places the result to the context, if necessary */
void PaintToContext();
private:
gfxContext* mContext;
gfxRect mNativeRect;
uint32_t mNativeDrawFlags;
// what state the rendering is in
uint8_t mRenderState;
mozilla::gfx::Point mDeviceOffset;
RefPtr<gfxPattern> mBlackPattern, mWhitePattern;
enum TransformType { TRANSLATION_ONLY, AXIS_ALIGNED_SCALE, COMPLEX };
TransformType mTransformType;
gfxPoint mTranslation;
mozilla::gfx::MatrixScalesDouble mScale;
XFORM mWorldTransform;
// saved state
RefPtr<gfxWindowsSurface> mWinSurface, mBlackSurface, mWhiteSurface;
HDC mDC;
XFORM mOldWorldTransform;
POINT mOrigViewportOrigin;
mozilla::gfx::IntSize mTempSurfaceSize;
};
#endif
