/* * Copyright 2013 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #include "SkBitmapProcState.h" #include "SkBitmap.h" #include "SkColor.h" #include "SkColorPriv.h" #include "SkUnPreMultiply.h" #include "SkRTConf.h" #include "SkShader.h" #define DS(x) SkDoubleToScalar(x) #define MUL(a, b) ((a) * (b)) static inline SkPMColor cubicBlend(const SkFixed cc[4], SkPMColor c0, SkPMColor c1, SkPMColor c2, SkPMColor c3) { SkFixed fa = MUL(cc[0], SkGetPackedA32(c0)) + MUL(cc[1], SkGetPackedA32(c1)) + MUL(cc[2], SkGetPackedA32(c2)) + MUL(cc[3], SkGetPackedA32(c3)); SkFixed fr = MUL(cc[0], SkGetPackedR32(c0)) + MUL(cc[1], SkGetPackedR32(c1)) + MUL(cc[2], SkGetPackedR32(c2)) + MUL(cc[3], SkGetPackedR32(c3)); SkFixed fg = MUL(cc[0], SkGetPackedG32(c0)) + MUL(cc[1], SkGetPackedG32(c1)) + MUL(cc[2], SkGetPackedG32(c2)) + MUL(cc[3], SkGetPackedG32(c3)); SkFixed fb = MUL(cc[0], SkGetPackedB32(c0)) + MUL(cc[1], SkGetPackedB32(c1)) + MUL(cc[2], SkGetPackedB32(c2)) + MUL(cc[3], SkGetPackedB32(c3)); int a = SkClampMax(SkFixedRoundToInt(fa), 255); int r = SkClampMax(SkFixedRoundToInt(fr), a); int g = SkClampMax(SkFixedRoundToInt(fg), a); int b = SkClampMax(SkFixedRoundToInt(fb), a); return SkPackARGB32(a, r, g, b); } static float poly_eval(const float cc[4], float t) { return cc[0] + t * (cc[1] + t * (cc[2] + t * cc[3])); } static void build_coeff4(SkFixed dst[4], float t) { static const SkScalar coefficients[16] = { DS( 1.0 / 18.0), DS(-9.0 / 18.0), DS( 15.0 / 18.0), DS( -7.0 / 18.0), DS(16.0 / 18.0), DS( 0.0 / 18.0), DS(-36.0 / 18.0), DS( 21.0 / 18.0), DS( 1.0 / 18.0), DS( 9.0 / 18.0), DS( 27.0 / 18.0), DS(-21.0 / 18.0), DS( 0.0 / 18.0), DS( 0.0 / 18.0), DS( -6.0 / 18.0), DS( 7.0 / 18.0), }; dst[0] = SkFloatToFixed(poly_eval(&coefficients[ 0], t)); dst[1] = SkFloatToFixed(poly_eval(&coefficients[ 4], t)); dst[2] = SkFloatToFixed(poly_eval(&coefficients[ 8], t)); dst[3] = SkFloatToFixed(poly_eval(&coefficients[12], t)); } static SkPMColor doBicubicFilter(const SkBitmap *bm, SkFixed coeffX[4], SkFixed coeffY[4], int x0, int x1, int x2, int x3, int y0, int y1, int y2, int y3 ) { SkPMColor s00 = *bm->getAddr32(x0, y0); SkPMColor s10 = *bm->getAddr32(x1, y0); SkPMColor s20 = *bm->getAddr32(x2, y0); SkPMColor s30 = *bm->getAddr32(x3, y0); SkPMColor s0 = cubicBlend(coeffX, s00, s10, s20, s30); SkPMColor s01 = *bm->getAddr32(x0, y1); SkPMColor s11 = *bm->getAddr32(x1, y1); SkPMColor s21 = *bm->getAddr32(x2, y1); SkPMColor s31 = *bm->getAddr32(x3, y1); SkPMColor s1 = cubicBlend(coeffX, s01, s11, s21, s31); SkPMColor s02 = *bm->getAddr32(x0, y2); SkPMColor s12 = *bm->getAddr32(x1, y2); SkPMColor s22 = *bm->getAddr32(x2, y2); SkPMColor s32 = *bm->getAddr32(x3, y2); SkPMColor s2 = cubicBlend(coeffX, s02, s12, s22, s32); SkPMColor s03 = *bm->getAddr32(x0, y3); SkPMColor s13 = *bm->getAddr32(x1, y3); SkPMColor s23 = *bm->getAddr32(x2, y3); SkPMColor s33 = *bm->getAddr32(x3, y3); SkPMColor s3 = cubicBlend(coeffX, s03, s13, s23, s33); return cubicBlend(coeffY, s0, s1, s2, s3); } static void bicubicFilter(const SkBitmapProcState& s, int x, int y, SkPMColor* SK_RESTRICT colors, int count) { const int maxX = s.fBitmap->width() - 1; const int maxY = s.fBitmap->height() - 1; while (count-- > 0) { SkPoint srcPt; s.fInvProc(*s.fInvMatrix, SkIntToScalar(x), SkIntToScalar(y), &srcPt); srcPt.fX -= SK_ScalarHalf; srcPt.fY -= SK_ScalarHalf; SkScalar fractx = srcPt.fX - SkScalarFloorToScalar(srcPt.fX); SkScalar fracty = srcPt.fY - SkScalarFloorToScalar(srcPt.fY); SkFixed coeffX[4], coeffY[4]; build_coeff4(coeffX, fractx); build_coeff4(coeffY, fracty); int sx = SkScalarFloorToInt(srcPt.fX); int sy = SkScalarFloorToInt(srcPt.fY); // Here is where we can support other tile modes (e.g. repeat or mirror) int x0 = SkClampMax(sx - 1, maxX); int x1 = SkClampMax(sx , maxX); int x2 = SkClampMax(sx + 1, maxX); int x3 = SkClampMax(sx + 2, maxX); int y0 = SkClampMax(sy - 1, maxY); int y1 = SkClampMax(sy , maxY); int y2 = SkClampMax(sy + 1, maxY); int y3 = SkClampMax(sy + 2, maxY); *colors++ = doBicubicFilter( s.fBitmap, coeffX, coeffY, x0, x1, x2, x3, y0, y1, y2, y3 ); x++; } } static void bicubicFilter_ScaleOnly(const SkBitmapProcState &s, int x, int y, SkPMColor *SK_RESTRICT colors, int count) { const int maxX = s.fBitmap->width() - 1; const int maxY = s.fBitmap->height() - 1; SkPoint srcPt; s.fInvProc(*s.fInvMatrix, SkIntToScalar(x), SkIntToScalar(y), &srcPt); srcPt.fY -= SK_ScalarHalf; SkScalar fracty = srcPt.fY - SkScalarFloorToScalar(srcPt.fY); SkFixed coeffX[4], coeffY[4]; build_coeff4(coeffY, fracty); int sy = SkScalarFloorToInt(srcPt.fY); int y0 = SkClampMax(sy - 1, maxY); int y1 = SkClampMax(sy , maxY); int y2 = SkClampMax(sy + 1, maxY); int y3 = SkClampMax(sy + 2, maxY); while (count-- > 0) { s.fInvProc(*s.fInvMatrix, SkIntToScalar(x), SkIntToScalar(y), &srcPt); srcPt.fX -= SK_ScalarHalf; SkScalar fractx = srcPt.fX - SkScalarFloorToScalar(srcPt.fX); build_coeff4(coeffX, fractx); int sx = SkScalarFloorToInt(srcPt.fX); // Here is where we can support other tile modes (e.g. repeat or mirror) int x0 = SkClampMax(sx - 1, maxX); int x1 = SkClampMax(sx , maxX); int x2 = SkClampMax(sx + 1, maxX); int x3 = SkClampMax(sx + 2, maxX); *colors++ = doBicubicFilter( s.fBitmap, coeffX, coeffY, x0, x1, x2, x3, y0, y1, y2, y3 ); x++; } } SkBitmapProcState::ShaderProc32 SkBitmapProcState::chooseBicubicFilterProc(const SkPaint& paint) { // we need to be requested uint32_t mask = SkPaint::kFilterBitmap_Flag | SkPaint::kBicubicFilterBitmap_Flag ; if ((paint.getFlags() & mask) != mask) { return NULL; } // TODO: consider supporting other configs (e.g. 565, A8) if (fBitmap->config() != SkBitmap::kARGB_8888_Config) { return NULL; } // TODO: consider supporting repeat and mirror if (SkShader::kClamp_TileMode != fTileModeX || SkShader::kClamp_TileMode != fTileModeY) { return NULL; } // TODO: support blending inside our procs if (0xFF != paint.getAlpha()) { return NULL; } if (fInvType & SkMatrix::kAffine_Mask) { return bicubicFilter; } else if (fInvType & SkMatrix::kScale_Mask) { return bicubicFilter_ScaleOnly; } else { return NULL; } }