| /* |
| * Copyright 2015 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef Sk4pxXfermode_DEFINED |
| #define Sk4pxXfermode_DEFINED |
| |
| #include "src/core/Sk4px.h" |
| #include "src/core/SkMSAN.h" |
| #include "src/core/SkXfermodePriv.h" |
| |
| #ifdef SK_FORCE_RASTER_PIPELINE_BLITTER |
| |
| namespace SK_OPTS_NS { |
| /*not static*/ inline SkXfermode* create_xfermode(SkBlendMode) { return nullptr; } |
| } |
| |
| #else |
| |
| namespace { // NOLINT(google-build-namespaces) |
| |
| // Most xfermodes can be done most efficiently 4 pixels at a time in 8 or 16-bit fixed point. |
| #define XFERMODE(Xfermode) \ |
| struct Xfermode { Sk4px operator()(const Sk4px&, const Sk4px&) const; }; \ |
| inline Sk4px Xfermode::operator()(const Sk4px& d, const Sk4px& s) const |
| |
| XFERMODE(Clear) { return Sk4px::DupPMColor(0); } |
| XFERMODE(Src) { return s; } |
| XFERMODE(Dst) { return d; } |
| XFERMODE(SrcIn) { return s.approxMulDiv255(d.alphas() ); } |
| XFERMODE(SrcOut) { return s.approxMulDiv255(d.alphas().inv()); } |
| XFERMODE(SrcOver) { return s + d.approxMulDiv255(s.alphas().inv()); } |
| XFERMODE(DstIn) { return SrcIn ()(s,d); } |
| XFERMODE(DstOut) { return SrcOut ()(s,d); } |
| XFERMODE(DstOver) { return SrcOver()(s,d); } |
| |
| // [ S * Da + (1 - Sa) * D] |
| XFERMODE(SrcATop) { return (s * d.alphas() + d * s.alphas().inv()).div255(); } |
| XFERMODE(DstATop) { return SrcATop()(s,d); } |
| //[ S * (1 - Da) + (1 - Sa) * D ] |
| XFERMODE(Xor) { return (s * d.alphas().inv() + d * s.alphas().inv()).div255(); } |
| // [S + D ] |
| XFERMODE(Plus) { return s.saturatedAdd(d); } |
| // [S * D ] |
| XFERMODE(Modulate) { return s.approxMulDiv255(d); } |
| // [S + D - S * D] |
| XFERMODE(Screen) { |
| // Doing the math as S + (1-S)*D or S + (D - S*D) means the add and subtract can be done |
| // in 8-bit space without overflow. S + (1-S)*D is a touch faster because inv() is cheap. |
| return s + d.approxMulDiv255(s.inv()); |
| } |
| |
| #undef XFERMODE |
| |
| // A reasonable fallback mode for doing AA is to simply apply the transfermode first, |
| // then linearly interpolate the AA. |
| template <typename Xfermode> |
| static Sk4px xfer_aa(const Sk4px& d, const Sk4px& s, const Sk4px& aa) { |
| Sk4px bw = Xfermode()(d, s); |
| return (bw * aa + d * aa.inv()).div255(); |
| } |
| |
| // For some transfermodes we specialize AA, either for correctness or performance. |
| #define XFERMODE_AA(Xfermode) \ |
| template <> inline Sk4px xfer_aa<Xfermode>(const Sk4px& d, const Sk4px& s, const Sk4px& aa) |
| |
| // Plus' clamp needs to happen after AA. skia:3852 |
| XFERMODE_AA(Plus) { // [ clamp( (1-AA)D + (AA)(S+D) ) == clamp(D + AA*S) ] |
| return d.saturatedAdd(s.approxMulDiv255(aa)); |
| } |
| |
| #undef XFERMODE_AA |
| |
| // Src and Clear modes are safe to use with uninitialized dst buffers, |
| // even if the implementation branches based on bytes from dst (e.g. asserts in Debug mode). |
| // For those modes, just lie to MSAN that dst is always intialized. |
| template <typename Xfermode> static void mark_dst_initialized_if_safe(void*, void*) {} |
| template <> inline void mark_dst_initialized_if_safe<Src>(void* dst, void* end) { |
| sk_msan_mark_initialized(dst, end, "Src doesn't read dst."); |
| } |
| template <> inline void mark_dst_initialized_if_safe<Clear>(void* dst, void* end) { |
| sk_msan_mark_initialized(dst, end, "Clear doesn't read dst."); |
| } |
| |
| template <typename Xfermode> |
| class Sk4pxXfermode : public SkXfermode { |
| public: |
| Sk4pxXfermode() {} |
| |
| void xfer32(SkPMColor dst[], const SkPMColor src[], int n, const SkAlpha aa[]) const override { |
| mark_dst_initialized_if_safe<Xfermode>(dst, dst+n); |
| if (nullptr == aa) { |
| Sk4px::MapDstSrc(n, dst, src, Xfermode()); |
| } else { |
| Sk4px::MapDstSrcAlpha(n, dst, src, aa, xfer_aa<Xfermode>); |
| } |
| } |
| }; |
| |
| } // namespace |
| |
| namespace SK_OPTS_NS { |
| |
| /*not static*/ inline SkXfermode* create_xfermode(SkBlendMode mode) { |
| switch (mode) { |
| #define CASE(Xfermode) \ |
| case SkBlendMode::k##Xfermode: return new Sk4pxXfermode<Xfermode>() |
| CASE(Clear); |
| CASE(Src); |
| CASE(Dst); |
| CASE(SrcOver); |
| CASE(DstOver); |
| CASE(SrcIn); |
| CASE(DstIn); |
| CASE(SrcOut); |
| CASE(DstOut); |
| CASE(SrcATop); |
| CASE(DstATop); |
| CASE(Xor); |
| CASE(Plus); |
| CASE(Modulate); |
| CASE(Screen); |
| #undef CASE |
| |
| default: break; |
| } |
| return nullptr; |
| } |
| |
| } // namespace SK_OPTS_NS |
| |
| #endif // #ifdef SK_FORCE_RASTER_PIPELINE_BLITTER |
| |
| #endif//Sk4pxXfermode_DEFINED |