michael@0: 
michael@0: /*
michael@0:  * Copyright 2011 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "SkPorterDuff.h"
michael@0: #include "SkXfermode.h"
michael@0: 
michael@0: /*  This file just exists as a compatibility layer, gluing the PorterDuff API
michael@0:     into the (extended) SkXfermode API
michael@0:  */
michael@0: 
michael@0: #define MAKE_PAIR(mode) { SkPorterDuff::k##mode##_Mode, SkXfermode::k##mode##_Mode }
michael@0: 
michael@0: // this table must be in SkPorterDuff::Mode order, so it can be indexed directly
michael@0: // with a porterduff mode.
michael@0: static const struct Pair {
michael@0:     SkPorterDuff::Mode  fPD;
michael@0:     SkXfermode::Mode    fXF;
michael@0: } gPairs[] = {
michael@0:     MAKE_PAIR(Clear),
michael@0:     MAKE_PAIR(Src),
michael@0:     MAKE_PAIR(Dst),
michael@0:     MAKE_PAIR(SrcOver),
michael@0:     MAKE_PAIR(DstOver),
michael@0:     MAKE_PAIR(SrcIn),
michael@0:     MAKE_PAIR(DstIn),
michael@0:     MAKE_PAIR(SrcOut),
michael@0:     MAKE_PAIR(DstOut),
michael@0:     MAKE_PAIR(SrcATop),
michael@0:     MAKE_PAIR(DstATop),
michael@0:     MAKE_PAIR(Xor),
michael@0:     MAKE_PAIR(Darken),
michael@0:     MAKE_PAIR(Lighten),
michael@0:     MAKE_PAIR(Modulate),
michael@0:     MAKE_PAIR(Screen),
michael@0:     { SkPorterDuff::kAdd_Mode, SkXfermode::kPlus_Mode },
michael@0: #ifdef SK_BUILD_FOR_ANDROID
michael@0:     MAKE_PAIR(Overlay),
michael@0: #endif
michael@0: };
michael@0: 
michael@0: static bool find_pdmode(SkXfermode::Mode src, SkPorterDuff::Mode* dst) {
michael@0:     const Pair* pairs = gPairs;
michael@0:     for (size_t i = 0; i < SK_ARRAY_COUNT(gPairs); i++) {
michael@0:         if (pairs[i].fXF == src) {
michael@0:             if (dst) {
michael@0:                 *dst = pairs[i].fPD;
michael@0:             }
michael@0:             return true;
michael@0:         }
michael@0:     }
michael@0:     return false;
michael@0: }
michael@0: 
michael@0: SkXfermode::Mode SkPorterDuff::ToXfermodeMode(Mode mode) {
michael@0:     SkASSERT((unsigned)mode < SkPorterDuff::kModeCount);
michael@0:     const Pair& pair = gPairs[mode];
michael@0:     SkASSERT(pair.fPD == mode);
michael@0:     return pair.fXF;
michael@0: }
michael@0: 
michael@0: SkXfermode* SkPorterDuff::CreateXfermode(SkPorterDuff::Mode mode) {
michael@0:     const Pair& pair = gPairs[mode];
michael@0:     SkASSERT(pair.fPD == mode);
michael@0:     return SkXfermode::Create(pair.fXF);
michael@0: }
michael@0: 
michael@0: bool SkPorterDuff::IsMode(SkXfermode* xfer, Mode* pdmode) {
michael@0:     SkXfermode::Mode xfmode;
michael@0:     if (!SkXfermode::AsMode(xfer, &xfmode)) {
michael@0:         return false;
michael@0:     }
michael@0:     return find_pdmode(xfmode, pdmode);
michael@0: }
michael@0: 
michael@0: SkXfermodeProc SkPorterDuff::GetXfermodeProc(Mode mode) {
michael@0:     return SkXfermode::GetProc(gPairs[mode].fXF);
michael@0: }
michael@0: 
michael@0: SkXfermodeProc16 SkPorterDuff::GetXfermodeProc16(Mode mode, SkColor srcColor) {
michael@0:     return SkXfermode::GetProc16(gPairs[mode].fXF, srcColor);
michael@0: }