1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/include/effects/SkPorterDuff.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,79 @@
1.4 +/*
1.5 + * Copyright 2006 The Android Open Source Project
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + */
1.10 +
1.11 +#ifndef SkPorterDuff_DEFINED
1.12 +#define SkPorterDuff_DEFINED
1.13 +
1.14 +#include "SkColor.h"
1.15 +#include "SkXfermode.h"
1.16 +
1.17 +class SkXfermode;
1.18 +
1.19 +class SK_API SkPorterDuff {
1.20 +public:
1.21 + /** List of predefined xfermodes. In general, the algebra for the modes
1.22 + uses the following symbols:
1.23 + Sa, Sc - source alpha and color
1.24 + Da, Dc - destination alpha and color (before compositing)
1.25 + [a, c] - Resulting (alpha, color) values
1.26 + For these equations, the colors are in premultiplied state.
1.27 + If no xfermode is specified, kSrcOver is assumed.
1.28 + */
1.29 + enum Mode {
1.30 + kClear_Mode, //!< [0, 0]
1.31 + kSrc_Mode, //!< [Sa, Sc]
1.32 + kDst_Mode, //!< [Da, Dc]
1.33 + kSrcOver_Mode, //!< [Sa + Da - Sa*Da, Rc = Sc + (1 - Sa)*Dc]
1.34 + kDstOver_Mode, //!< [Sa + Da - Sa*Da, Rc = Dc + (1 - Da)*Sc]
1.35 + kSrcIn_Mode, //!< [Sa * Da, Sc * Da]
1.36 + kDstIn_Mode, //!< [Sa * Da, Sa * Dc]
1.37 + kSrcOut_Mode, //!< [Sa * (1 - Da), Sc * (1 - Da)]
1.38 + kDstOut_Mode, //!< [Da * (1 - Sa), Dc * (1 - Sa)]
1.39 + kSrcATop_Mode, //!< [Da, Sc * Da + (1 - Sa) * Dc]
1.40 + kDstATop_Mode, //!< [Sa, Sa * Dc + Sc * (1 - Da)]
1.41 + kXor_Mode, //!< [Sa + Da - 2 * Sa * Da, Sc * (1 - Da) + (1 - Sa) * Dc]
1.42 + kDarken_Mode, //!< [Sa + Da - Sa*Da, Sc*(1 - Da) + Dc*(1 - Sa) + min(Sc, Dc)]
1.43 + kLighten_Mode, //!< [Sa + Da - Sa*Da, Sc*(1 - Da) + Dc*(1 - Sa) + max(Sc, Dc)]
1.44 + kModulate_Mode, //!< [Sa * Da, Sc * Dc] multiplies all components
1.45 + kScreen_Mode, //!< [Sa + Da - Sa * Da, Sc + Dc - Sc * Dc]
1.46 + kAdd_Mode, //!< Saturate(S + D)
1.47 +#ifdef SK_BUILD_FOR_ANDROID
1.48 + kOverlay_Mode,
1.49 +#endif
1.50 +
1.51 + kModeCount
1.52 + };
1.53 +
1.54 + /** Return an SkXfermode object for the specified mode.
1.55 + */
1.56 + static SkXfermode* CreateXfermode(Mode mode);
1.57 +
1.58 + /** Return a function pointer to a routine that applies the specified
1.59 + porter-duff transfer mode.
1.60 + */
1.61 + static SkXfermodeProc GetXfermodeProc(Mode mode);
1.62 +
1.63 + /** Return a function pointer to a routine that applies the specified
1.64 + porter-duff transfer mode and srcColor to a 16bit device color. Note,
1.65 + if the mode+srcColor might return a non-opaque color, then there is not
1.66 + 16bit proc, and this will return NULL.
1.67 + */
1.68 + static SkXfermodeProc16 GetXfermodeProc16(Mode mode, SkColor srcColor);
1.69 +
1.70 + /** If the specified xfermode advertises itself as one of the porterduff
1.71 + modes (via SkXfermode::Coeff), return true and if not null, set mode
1.72 + to the corresponding porterduff mode. If it is not recognized as a one,
1.73 + return false and ignore the mode parameter.
1.74 + */
1.75 + static bool IsMode(SkXfermode*, Mode* mode);
1.76 +
1.77 + /** Return the corersponding SkXfermode::Mode
1.78 + */
1.79 + static SkXfermode::Mode ToXfermodeMode(Mode);
1.80 +} SK_ATTR_DEPRECATED("use SkXfermode::Mode");
1.81 +
1.82 +#endif
