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: #include "SkBlitRow.h"
michael@0: #include "SkColorPriv.h"
michael@0: #include "SkDither.h"
michael@0: #include "SkMathPriv.h"
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: static void S32_D565_Opaque(uint16_t* SK_RESTRICT dst,
michael@0:                             const SkPMColor* SK_RESTRICT src, int count,
michael@0:                             U8CPU alpha, int /*x*/, int /*y*/) {
michael@0:     SkASSERT(255 == alpha);
michael@0: 
michael@0:     if (count > 0) {
michael@0:         do {
michael@0:             SkPMColor c = *src++;
michael@0:             SkPMColorAssert(c);
michael@0:             *dst++ = SkPixel32ToPixel16_ToU16(c);
michael@0:         } while (--count != 0);
michael@0:     }
michael@0: }
michael@0: 
michael@0: static void S32_D565_Blend(uint16_t* SK_RESTRICT dst,
michael@0:                              const SkPMColor* SK_RESTRICT src, int count,
michael@0:                              U8CPU alpha, int /*x*/, int /*y*/) {
michael@0:     SkASSERT(255 > alpha);
michael@0: 
michael@0:     if (count > 0) {
michael@0:         int scale = SkAlpha255To256(alpha);
michael@0:         do {
michael@0:             SkPMColor c = *src++;
michael@0:             SkPMColorAssert(c);
michael@0:             uint16_t d = *dst;
michael@0:             *dst++ = SkPackRGB16(
michael@0:                     SkAlphaBlend(SkPacked32ToR16(c), SkGetPackedR16(d), scale),
michael@0:                     SkAlphaBlend(SkPacked32ToG16(c), SkGetPackedG16(d), scale),
michael@0:                     SkAlphaBlend(SkPacked32ToB16(c), SkGetPackedB16(d), scale));
michael@0:         } while (--count != 0);
michael@0:     }
michael@0: }
michael@0: 
michael@0: static void S32A_D565_Opaque(uint16_t* SK_RESTRICT dst,
michael@0:                                const SkPMColor* SK_RESTRICT src, int count,
michael@0:                                U8CPU alpha, int /*x*/, int /*y*/) {
michael@0:     SkASSERT(255 == alpha);
michael@0: 
michael@0:     if (count > 0) {
michael@0:         do {
michael@0:             SkPMColor c = *src++;
michael@0:             SkPMColorAssert(c);
michael@0: //            if (__builtin_expect(c!=0, 1))
michael@0:             if (c) {
michael@0:                 *dst = SkSrcOver32To16(c, *dst);
michael@0:             }
michael@0:             dst += 1;
michael@0:         } while (--count != 0);
michael@0:     }
michael@0: }
michael@0: 
michael@0: static void S32A_D565_Blend(uint16_t* SK_RESTRICT dst,
michael@0:                               const SkPMColor* SK_RESTRICT src, int count,
michael@0:                                U8CPU alpha, int /*x*/, int /*y*/) {
michael@0:     SkASSERT(255 > alpha);
michael@0: 
michael@0:     if (count > 0) {
michael@0:         do {
michael@0:             SkPMColor sc = *src++;
michael@0:             SkPMColorAssert(sc);
michael@0:             if (sc) {
michael@0:                 uint16_t dc = *dst;
michael@0:                 unsigned dst_scale = 255 - SkMulDiv255Round(SkGetPackedA32(sc), alpha);
michael@0:                 unsigned dr = SkMulS16(SkPacked32ToR16(sc), alpha) + SkMulS16(SkGetPackedR16(dc), dst_scale);
michael@0:                 unsigned dg = SkMulS16(SkPacked32ToG16(sc), alpha) + SkMulS16(SkGetPackedG16(dc), dst_scale);
michael@0:                 unsigned db = SkMulS16(SkPacked32ToB16(sc), alpha) + SkMulS16(SkGetPackedB16(dc), dst_scale);
michael@0:                 *dst = SkPackRGB16(SkDiv255Round(dr), SkDiv255Round(dg), SkDiv255Round(db));
michael@0:             }
michael@0:             dst += 1;
michael@0:         } while (--count != 0);
michael@0:     }
michael@0: }
michael@0: 
michael@0: /////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: static void S32_D565_Opaque_Dither(uint16_t* SK_RESTRICT dst,
michael@0:                                      const SkPMColor* SK_RESTRICT src,
michael@0:                                      int count, U8CPU alpha, int x, int y) {
michael@0:     SkASSERT(255 == alpha);
michael@0: 
michael@0:     if (count > 0) {
michael@0:         DITHER_565_SCAN(y);
michael@0:         do {
michael@0:             SkPMColor c = *src++;
michael@0:             SkPMColorAssert(c);
michael@0: 
michael@0:             unsigned dither = DITHER_VALUE(x);
michael@0:             *dst++ = SkDitherRGB32To565(c, dither);
michael@0:             DITHER_INC_X(x);
michael@0:         } while (--count != 0);
michael@0:     }
michael@0: }
michael@0: 
michael@0: static void S32_D565_Blend_Dither(uint16_t* SK_RESTRICT dst,
michael@0:                                     const SkPMColor* SK_RESTRICT src,
michael@0:                                     int count, U8CPU alpha, int x, int y) {
michael@0:     SkASSERT(255 > alpha);
michael@0: 
michael@0:     if (count > 0) {
michael@0:         int scale = SkAlpha255To256(alpha);
michael@0:         DITHER_565_SCAN(y);
michael@0:         do {
michael@0:             SkPMColor c = *src++;
michael@0:             SkPMColorAssert(c);
michael@0: 
michael@0:             int dither = DITHER_VALUE(x);
michael@0:             int sr = SkGetPackedR32(c);
michael@0:             int sg = SkGetPackedG32(c);
michael@0:             int sb = SkGetPackedB32(c);
michael@0:             sr = SkDITHER_R32To565(sr, dither);
michael@0:             sg = SkDITHER_G32To565(sg, dither);
michael@0:             sb = SkDITHER_B32To565(sb, dither);
michael@0: 
michael@0:             uint16_t d = *dst;
michael@0:             *dst++ = SkPackRGB16(SkAlphaBlend(sr, SkGetPackedR16(d), scale),
michael@0:                                  SkAlphaBlend(sg, SkGetPackedG16(d), scale),
michael@0:                                  SkAlphaBlend(sb, SkGetPackedB16(d), scale));
michael@0:             DITHER_INC_X(x);
michael@0:         } while (--count != 0);
michael@0:     }
michael@0: }
michael@0: 
michael@0: static void S32A_D565_Opaque_Dither(uint16_t* SK_RESTRICT dst,
michael@0:                                       const SkPMColor* SK_RESTRICT src,
michael@0:                                       int count, U8CPU alpha, int x, int y) {
michael@0:     SkASSERT(255 == alpha);
michael@0: 
michael@0:     if (count > 0) {
michael@0:         DITHER_565_SCAN(y);
michael@0:         do {
michael@0:             SkPMColor c = *src++;
michael@0:             SkPMColorAssert(c);
michael@0:             if (c) {
michael@0:                 unsigned a = SkGetPackedA32(c);
michael@0: 
michael@0:                 int d = SkAlphaMul(DITHER_VALUE(x), SkAlpha255To256(a));
michael@0: 
michael@0:                 unsigned sr = SkGetPackedR32(c);
michael@0:                 unsigned sg = SkGetPackedG32(c);
michael@0:                 unsigned sb = SkGetPackedB32(c);
michael@0:                 sr = SkDITHER_R32_FOR_565(sr, d);
michael@0:                 sg = SkDITHER_G32_FOR_565(sg, d);
michael@0:                 sb = SkDITHER_B32_FOR_565(sb, d);
michael@0: 
michael@0:                 uint32_t src_expanded = (sg << 24) | (sr << 13) | (sb << 2);
michael@0:                 uint32_t dst_expanded = SkExpand_rgb_16(*dst);
michael@0:                 dst_expanded = dst_expanded * (SkAlpha255To256(255 - a) >> 3);
michael@0:                 // now src and dst expanded are in g:11 r:10 x:1 b:10
michael@0:                 *dst = SkCompact_rgb_16((src_expanded + dst_expanded) >> 5);
michael@0:             }
michael@0:             dst += 1;
michael@0:             DITHER_INC_X(x);
michael@0:         } while (--count != 0);
michael@0:     }
michael@0: }
michael@0: 
michael@0: static void S32A_D565_Blend_Dither(uint16_t* SK_RESTRICT dst,
michael@0:                                      const SkPMColor* SK_RESTRICT src,
michael@0:                                      int count, U8CPU alpha, int x, int y) {
michael@0:     SkASSERT(255 > alpha);
michael@0: 
michael@0:     if (count > 0) {
michael@0:         int src_scale = SkAlpha255To256(alpha);
michael@0:         DITHER_565_SCAN(y);
michael@0:         do {
michael@0:             SkPMColor c = *src++;
michael@0:             SkPMColorAssert(c);
michael@0:             if (c)
michael@0:             {
michael@0:                 unsigned d = *dst;
michael@0:                 int sa = SkGetPackedA32(c);
michael@0:                 int dst_scale = SkAlpha255To256(255 - SkAlphaMul(sa, src_scale));
michael@0:                 int dither = DITHER_VALUE(x);
michael@0: 
michael@0:                 int sr = SkGetPackedR32(c);
michael@0:                 int sg = SkGetPackedG32(c);
michael@0:                 int sb = SkGetPackedB32(c);
michael@0:                 sr = SkDITHER_R32To565(sr, dither);
michael@0:                 sg = SkDITHER_G32To565(sg, dither);
michael@0:                 sb = SkDITHER_B32To565(sb, dither);
michael@0: 
michael@0:                 int dr = (sr * src_scale + SkGetPackedR16(d) * dst_scale) >> 8;
michael@0:                 int dg = (sg * src_scale + SkGetPackedG16(d) * dst_scale) >> 8;
michael@0:                 int db = (sb * src_scale + SkGetPackedB16(d) * dst_scale) >> 8;
michael@0: 
michael@0:                 *dst = SkPackRGB16(dr, dg, db);
michael@0:             }
michael@0:             dst += 1;
michael@0:             DITHER_INC_X(x);
michael@0:         } while (--count != 0);
michael@0:     }
michael@0: }
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: static const SkBlitRow::Proc gDefault_565_Procs[] = {
michael@0:     // no dither
michael@0:     S32_D565_Opaque,
michael@0:     S32_D565_Blend,
michael@0: 
michael@0:     S32A_D565_Opaque,
michael@0:     S32A_D565_Blend,
michael@0: 
michael@0:     // dither
michael@0:     S32_D565_Opaque_Dither,
michael@0:     S32_D565_Blend_Dither,
michael@0: 
michael@0:     S32A_D565_Opaque_Dither,
michael@0:     S32A_D565_Blend_Dither
michael@0: };
michael@0: 
michael@0: SkBlitRow::Proc SkBlitRow::Factory(unsigned flags, SkBitmap::Config config) {
michael@0:     SkASSERT(flags < SK_ARRAY_COUNT(gDefault_565_Procs));
michael@0:     // just so we don't crash
michael@0:     flags &= kFlags16_Mask;
michael@0: 
michael@0:     SkBlitRow::Proc proc = NULL;
michael@0: 
michael@0:     switch (config) {
michael@0:         case SkBitmap::kRGB_565_Config:
michael@0:             proc = PlatformProcs565(flags);
michael@0:             if (NULL == proc) {
michael@0:                 proc = gDefault_565_Procs[flags];
michael@0:             }
michael@0:             break;
michael@0:         default:
michael@0:             break;
michael@0:     }
michael@0:     return proc;
michael@0: }