Move SkAvoidXfermode over from Android
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1649503002
Review URL: https://codereview.chromium.org/1649503002
diff --git a/gm/avoidxfermode.cpp b/gm/avoidxfermode.cpp
new file mode 100644
index 0000000..0d681cb
--- /dev/null
+++ b/gm/avoidxfermode.cpp
@@ -0,0 +1,99 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "gm.h"
+#include "Resources.h"
+
+#include "SkImageDecoder.h"
+#include "SkAvoidXfermode.h"
+#include "SkStream.h"
+
+class AvoidXfermodeGM : public skiagm::GM {
+public:
+ AvoidXfermodeGM() { }
+
+protected:
+ SkString onShortName() override {
+ return SkString("avoidxfermode");
+ }
+
+ SkISize onISize() override { return SkISize::Make(128, 128); }
+
+ void onOnceBeforeDraw() override {
+ SkImageDecoder* codec = nullptr;
+ SkString resourcePath = GetResourcePath("color_wheel.png");
+ SkFILEStream stream(resourcePath.c_str());
+ if (stream.isValid()) {
+ codec = SkImageDecoder::Factory(&stream);
+ }
+ if (codec) {
+ stream.rewind();
+ codec->decode(&stream, &fBM, kN32_SkColorType, SkImageDecoder::kDecodePixels_Mode);
+ delete codec;
+ } else {
+ fBM.allocN32Pixels(1, 1);
+ fBM.eraseARGB(255, 255, 0 , 0); // red == bad
+ }
+ }
+
+ void onDraw(SkCanvas* canvas) override {
+ canvas->drawBitmap(fBM, 0, 0);
+
+ SkRect r = SkRect::MakeIWH(64, 64);
+
+ // UL corner: replace white with black with a tight tolerance
+ SkPaint p1;
+ p1.setColor(SK_ColorBLACK);
+ p1.setXfermode(SkAvoidXfermode::Create(SK_ColorWHITE,
+ 5,
+ SkAvoidXfermode::kTargetColor_Mode))->unref();
+
+ canvas->drawRect(r, p1);
+
+ r.offsetTo(64, 0.0f);
+
+ // UR corner: draw black everywhere except white with a tight tolerance
+ SkPaint p2;
+ p2.setColor(SK_ColorBLACK);
+ p2.setXfermode(SkAvoidXfermode::Create(SK_ColorWHITE,
+ 250,
+ SkAvoidXfermode::kAvoidColor_Mode))->unref();
+
+ canvas->drawRect(r, p2);
+
+ r.offsetTo(0.0f, 64);
+
+ // LL corner: replace red with blue with a loose tolerance
+ SkPaint p3;
+ p3.setColor(SK_ColorBLUE);
+ p3.setXfermode(SkAvoidXfermode::Create(SK_ColorRED,
+ 250,
+ SkAvoidXfermode::kTargetColor_Mode))->unref();
+
+ canvas->drawRect(r, p3);
+
+ r.offsetTo(64, 64);
+
+ // LR corner: draw black everywhere except red with a loose tolerance
+ SkPaint p4;
+ p4.setColor(SK_ColorBLACK);
+ p4.setXfermode(SkAvoidXfermode::Create(SK_ColorRED,
+ 5,
+ SkAvoidXfermode::kAvoidColor_Mode))->unref();
+
+ canvas->drawRect(r, p4);
+ }
+
+private:
+ SkBitmap fBM;
+
+ typedef GM INHERITED;
+};
+
+//////////////////////////////////////////////////////////////////////////////
+
+DEF_GM(return new AvoidXfermodeGM;)
diff --git a/gyp/effects.gypi b/gyp/effects.gypi
index af09357..cee399d 100644
--- a/gyp/effects.gypi
+++ b/gyp/effects.gypi
@@ -21,6 +21,7 @@
'<(skia_src_path)/effects/SkArithmeticMode.cpp',
'<(skia_src_path)/effects/SkArithmeticMode_gpu.cpp',
'<(skia_src_path)/effects/SkArithmeticMode_gpu.h',
+ '<(skia_src_path)/effects/SkAvoidXfermode.cpp',
'<(skia_src_path)/effects/SkBlurDrawLooper.cpp',
'<(skia_src_path)/effects/SkBlurMask.cpp',
'<(skia_src_path)/effects/SkBlurMask.h',
@@ -84,6 +85,7 @@
'<(skia_include_path)/effects/Sk2DPathEffect.h',
'<(skia_include_path)/effects/SkAlphaThresholdFilter.h',
'<(skia_include_path)/effects/SkArithmeticMode.h',
+ '<(skia_include_path)/effects/SkAvoidXfermode.h',
'<(skia_include_path)/effects/SkBlurDrawLooper.h',
'<(skia_include_path)/effects/SkBlurImageFilter.h',
'<(skia_include_path)/effects/SkBlurMaskFilter.h',
diff --git a/include/effects/SkAvoidXfermode.h b/include/effects/SkAvoidXfermode.h
new file mode 100644
index 0000000..bcd42a5
--- /dev/null
+++ b/include/effects/SkAvoidXfermode.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright 2006 The Android Open Source Project
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkAvoidXfermode_DEFINED
+#define SkAvoidXfermode_DEFINED
+
+#include "SkColor.h"
+#include "SkTypes.h"
+#include "SkXfermode.h"
+
+/** \class AvoidXfermode
+
+ This xfermode will draw the src everywhere except on top of the specified
+ color.
+*/
+class SkAvoidXfermode : public SkXfermode {
+public:
+ enum Mode {
+ kAvoidColor_Mode, //!< draw everywhere except on the opColor
+ kTargetColor_Mode //!< draw only on top of the opColor
+ };
+
+ /** This xfermode draws, or doesn't draw, based on the destination's
+ distance from an op-color.
+
+ There are two modes, and each mode interprets a tolerance value.
+
+ Avoid: In this mode, drawing is allowed only on destination pixels that
+ are different from the op-color.
+ Tolerance near 0: avoid any colors even remotely similar to the op-color
+ Tolerance near 255: avoid only colors nearly identical to the op-color
+
+ Target: In this mode, drawing only occurs on destination pixels that
+ are similar to the op-color
+ Tolerance near 0: draw only on colors that are nearly identical to the op-color
+ Tolerance near 255: draw on any colors even remotely similar to the op-color
+ */
+ static SkAvoidXfermode* Create(SkColor opColor, U8CPU tolerance, Mode mode) {
+ return new SkAvoidXfermode(opColor, tolerance, mode);
+ }
+
+ // overrides from SkXfermode
+ void xfer32(SkPMColor dst[], const SkPMColor src[], int count,
+ const SkAlpha aa[]) const override;
+ void xfer16(uint16_t dst[], const SkPMColor src[], int count,
+ const SkAlpha aa[]) const override;
+ void xferA8(SkAlpha dst[], const SkPMColor src[], int count,
+ const SkAlpha aa[]) const override;
+
+ SK_TO_STRING_OVERRIDE()
+ SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(AvoidXfermode)
+
+protected:
+ SkAvoidXfermode(SkColor opColor, U8CPU tolerance, Mode mode);
+ void flatten(SkWriteBuffer&) const override;
+
+private:
+ SkColor fOpColor;
+ uint32_t fDistMul; // x.14 cached from fTolerance
+ uint8_t fTolerance;
+ Mode fMode;
+
+ typedef SkXfermode INHERITED;
+};
+
+#endif
diff --git a/src/effects/SkAvoidXfermode.cpp b/src/effects/SkAvoidXfermode.cpp
new file mode 100644
index 0000000..d0aa44f
--- /dev/null
+++ b/src/effects/SkAvoidXfermode.cpp
@@ -0,0 +1,177 @@
+/*
+ * Copyright 2006 The Android Open Source Project
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkAvoidXfermode.h"
+#include "SkColorPriv.h"
+#include "SkReadBuffer.h"
+#include "SkWriteBuffer.h"
+#include "SkString.h"
+
+SkAvoidXfermode::SkAvoidXfermode(SkColor opColor, U8CPU tolerance, Mode mode) {
+ if (tolerance > 255) {
+ tolerance = 255;
+ }
+ fTolerance = SkToU8(tolerance);
+ fOpColor = opColor;
+ fDistMul = (256 << 14) / (tolerance + 1);
+ fMode = mode;
+}
+
+SkFlattenable* SkAvoidXfermode::CreateProc(SkReadBuffer& buffer) {
+ const SkColor color = buffer.readColor();
+ const unsigned tolerance = buffer.readUInt();
+ const unsigned mode = buffer.readUInt();
+ return Create(color, tolerance, (Mode)mode);
+}
+
+void SkAvoidXfermode::flatten(SkWriteBuffer& buffer) const {
+ buffer.writeColor(fOpColor);
+ buffer.writeUInt(fTolerance);
+ buffer.writeUInt(fMode);
+}
+
+// returns 0..31
+static unsigned color_dist16(uint16_t c, unsigned r, unsigned g, unsigned b) {
+ SkASSERT(r <= SK_R16_MASK);
+ SkASSERT(g <= SK_G16_MASK);
+ SkASSERT(b <= SK_B16_MASK);
+
+ unsigned dr = SkAbs32(SkGetPackedR16(c) - r);
+ unsigned dg = SkAbs32(SkGetPackedG16(c) - g) >> (SK_G16_BITS - SK_R16_BITS);
+ unsigned db = SkAbs32(SkGetPackedB16(c) - b);
+
+ return SkMax32(dr, SkMax32(dg, db));
+}
+
+// returns 0..255
+static unsigned color_dist32(SkPMColor c, U8CPU r, U8CPU g, U8CPU b) {
+ SkASSERT(r <= 0xFF);
+ SkASSERT(g <= 0xFF);
+ SkASSERT(b <= 0xFF);
+
+ unsigned dr = SkAbs32(SkGetPackedR32(c) - r);
+ unsigned dg = SkAbs32(SkGetPackedG32(c) - g);
+ unsigned db = SkAbs32(SkGetPackedB32(c) - b);
+
+ return SkMax32(dr, SkMax32(dg, db));
+}
+
+static int scale_dist_14(int dist, uint32_t mul, uint32_t sub) {
+ int tmp = dist * mul - sub;
+ int result = (tmp + (1 << 13)) >> 14;
+
+ return result;
+}
+
+static inline unsigned Accurate255To256(unsigned x) {
+ return x + (x >> 7);
+}
+
+void SkAvoidXfermode::xfer32(SkPMColor dst[], const SkPMColor src[], int count,
+ const SkAlpha aa[]) const {
+ unsigned opR = SkColorGetR(fOpColor);
+ unsigned opG = SkColorGetG(fOpColor);
+ unsigned opB = SkColorGetB(fOpColor);
+ uint32_t mul = fDistMul;
+ uint32_t sub = (fDistMul - (1 << 14)) << 8;
+
+ int MAX, mask;
+
+ if (kTargetColor_Mode == fMode) {
+ mask = -1;
+ MAX = 255;
+ } else {
+ mask = 0;
+ MAX = 0;
+ }
+
+ for (int i = 0; i < count; i++) {
+ int d = color_dist32(dst[i], opR, opG, opB);
+ // now reverse d if we need to
+ d = MAX + (d ^ mask) - mask;
+ SkASSERT((unsigned)d <= 255);
+ d = Accurate255To256(d);
+
+ d = scale_dist_14(d, mul, sub);
+ SkASSERT(d <= 256);
+
+ if (d > 0) {
+ if (aa) {
+ d = SkAlphaMul(d, Accurate255To256(*aa++));
+ if (0 == d) {
+ continue;
+ }
+ }
+ dst[i] = SkFourByteInterp256(src[i], dst[i], d);
+ }
+ }
+}
+
+static inline U16CPU SkBlend3216(SkPMColor src, U16CPU dst, unsigned scale) {
+ SkASSERT(scale <= 32);
+ scale <<= 3;
+
+ return SkPackRGB16(SkAlphaBlend(SkPacked32ToR16(src), SkGetPackedR16(dst), scale),
+ SkAlphaBlend(SkPacked32ToG16(src), SkGetPackedG16(dst), scale),
+ SkAlphaBlend(SkPacked32ToB16(src), SkGetPackedB16(dst), scale));
+}
+
+void SkAvoidXfermode::xfer16(uint16_t dst[], const SkPMColor src[], int count,
+ const SkAlpha aa[]) const {
+ unsigned opR = SkColorGetR(fOpColor) >> (8 - SK_R16_BITS);
+ unsigned opG = SkColorGetG(fOpColor) >> (8 - SK_G16_BITS);
+ unsigned opB = SkColorGetB(fOpColor) >> (8 - SK_R16_BITS);
+ uint32_t mul = fDistMul;
+ uint32_t sub = (fDistMul - (1 << 14)) << SK_R16_BITS;
+
+ int MAX, mask;
+
+ if (kTargetColor_Mode == fMode) {
+ mask = -1;
+ MAX = 31;
+ } else {
+ mask = 0;
+ MAX = 0;
+ }
+
+ for (int i = 0; i < count; i++) {
+ int d = color_dist16(dst[i], opR, opG, opB);
+ // now reverse d if we need to
+ d = MAX + (d ^ mask) - mask;
+ SkASSERT((unsigned)d <= 31);
+ // convert from 0..31 to 0..32
+ d += d >> 4;
+ d = scale_dist_14(d, mul, sub);
+ SkASSERT(d <= 32);
+
+ if (d > 0) {
+ if (aa) {
+ d = SkAlphaMul(d, Accurate255To256(*aa++));
+ if (0 == d) {
+ continue;
+ }
+ }
+ dst[i] = SkBlend3216(src[i], dst[i], d);
+ }
+ }
+}
+
+void SkAvoidXfermode::xferA8(SkAlpha dst[], const SkPMColor src[], int count,
+ const SkAlpha aa[]) const {
+}
+
+#ifndef SK_IGNORE_TO_STRING
+void SkAvoidXfermode::toString(SkString* str) const {
+ str->append("AvoidXfermode: opColor: ");
+ str->appendHex(fOpColor);
+ str->appendf("distMul: %d ", fDistMul);
+
+ static const char* gModeStrings[] = { "Avoid", "Target" };
+
+ str->appendf("mode: %s", gModeStrings[fMode]);
+}
+#endif
diff --git a/src/ports/SkGlobalInitialization_default.cpp b/src/ports/SkGlobalInitialization_default.cpp
index de50527..4c06817 100644
--- a/src/ports/SkGlobalInitialization_default.cpp
+++ b/src/ports/SkGlobalInitialization_default.cpp
@@ -10,6 +10,7 @@
#include "SkAlphaThresholdFilter.h"
#include "SkArithmeticMode.h"
#include "SkArcToPathEffect.h"
+#include "SkAvoidXfermode.h"
#include "SkBitmapSourceDeserializer.h"
#include "SkBlurDrawLooper.h"
#include "SkBlurImageFilter.h"
@@ -82,6 +83,7 @@
// Xfermode
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkPixelXorXfermode)
+ SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkAvoidXfermode)
// PathEffect
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkArcToPathEffect)