add table maskfilter
http://b/issue?id=2210685
diff --git a/Android.mk b/Android.mk
index 3d03194..ca78321 100644
--- a/Android.mk
+++ b/Android.mk
@@ -55,6 +55,7 @@
src/effects/SkPaintFlagsDrawFilter.cpp \
src/effects/SkPixelXorXfermode.cpp \
src/effects/SkPorterDuff.cpp \
+ src/effects/SkTableMaskFilter.cpp \
src/effects/SkTransparentShader.cpp \
src/images/bmpdecoderhelper.cpp \
src/images/SkFDStream.cpp \
diff --git a/include/effects/SkTableMaskFilter.h b/include/effects/SkTableMaskFilter.h
new file mode 100644
index 0000000..a57053d
--- /dev/null
+++ b/include/effects/SkTableMaskFilter.h
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2006 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef SkTableMaskFilter_DEFINED
+#define SkTableMaskFilter_DEFINED
+
+#include "SkMaskFilter.h"
+#include "SkScalar.h"
+
+/** \class SkTableMaskFilter
+
+ Applies a table lookup on each of the alpha values in the mask.
+ Helper methods create some common tables (e.g. gamma, clipping)
+ */
+class SkTableMaskFilter : public SkMaskFilter {
+public:
+ SkTableMaskFilter();
+ SkTableMaskFilter(const uint8_t table[256]);
+ virtual ~SkTableMaskFilter();
+
+ void setTable(const uint8_t table[256]);
+
+ /** Utility that sets the gamma table
+ */
+ static void MakeGammaTable(uint8_t table[256], SkScalar gamma);
+
+ /** Utility that creates a clipping table: clamps values below min to 0
+ and above max to 255, and rescales the remaining into 0..255
+ */
+ static void MakeClipTable(uint8_t table[256], uint8_t min, uint8_t max);
+
+ static SkTableMaskFilter* CreateGamma(SkScalar gamma) {
+ uint8_t table[256];
+ MakeGammaTable(table, gamma);
+ return SkNEW_ARGS(SkTableMaskFilter, (table));
+ }
+
+ static SkTableMaskFilter* CreateClip(uint8_t min, uint8_t max) {
+ uint8_t table[256];
+ MakeClipTable(table, min, max);
+ return SkNEW_ARGS(SkTableMaskFilter, (table));
+ }
+
+ // overrides from SkMaskFilter
+ virtual SkMask::Format getFormat();
+ virtual bool filterMask(SkMask*, const SkMask&, const SkMatrix&, SkIPoint*);
+
+ // overrides from SkFlattenable
+ virtual void flatten(SkFlattenableWriteBuffer& wb);
+ virtual Factory getFactory();
+
+protected:
+ SkTableMaskFilter(SkFlattenableReadBuffer& rb);
+ static SkFlattenable* Factory(SkFlattenableReadBuffer&);
+
+private:
+ uint8_t fTable[256];
+
+ typedef SkMaskFilter INHERITED;
+};
+
+#endif
+
diff --git a/src/effects/SkTableMaskFilter.cpp b/src/effects/SkTableMaskFilter.cpp
new file mode 100644
index 0000000..aea939f
--- /dev/null
+++ b/src/effects/SkTableMaskFilter.cpp
@@ -0,0 +1,127 @@
+#include "SkTableMaskFilter.h"
+
+SkTableMaskFilter::SkTableMaskFilter() {
+ for (int i = 0; i < 256; i++) {
+ fTable[i] = i;
+ }
+}
+
+SkTableMaskFilter::SkTableMaskFilter(const uint8_t table[256]) {
+ this->setTable(table);
+}
+
+SkTableMaskFilter::~SkTableMaskFilter() {}
+
+void SkTableMaskFilter::setTable(const uint8_t table[256]) {
+ memcpy(fTable, table, 256);
+}
+
+bool SkTableMaskFilter::filterMask(SkMask* dst, const SkMask& src,
+ const SkMatrix&, SkIPoint* margin) {
+ if (src.fFormat != SkMask::kA8_Format) {
+ return false;
+ }
+
+ dst->fBounds = src.fBounds;
+ dst->fRowBytes = SkAlign4(dst->fBounds.width());
+ dst->fFormat = SkMask::kA8_Format;
+ dst->fImage = NULL;
+
+ if (src.fImage) {
+ dst->fImage = SkMask::AllocImage(dst->computeImageSize());
+
+ const uint8_t* srcP = src.fImage;
+ uint8_t* dstP = dst->fImage;
+ const uint8_t* table = fTable;
+ int dstWidth = dst->fBounds.width();
+ int extraZeros = dst->fRowBytes - dstWidth;
+
+ for (int y = dst->fBounds.height() - 1; y >= 0; --y) {
+ for (int x = dstWidth - 1; x >= 0; --x) {
+ dstP[x] = table[srcP[x]];
+ }
+ srcP += src.fRowBytes;
+ // we can't just inc dstP by rowbytes, because if it has any
+ // padding between its width and its rowbytes, we need to zero those
+ // so that the bitters can read those safely if that is faster for
+ // them
+ dstP += dstWidth;
+ for (int i = extraZeros - 1; i >= 0; --i) {
+ *dstP++ = 0;
+ }
+ }
+ }
+
+ if (margin) {
+ margin->set(0, 0);
+ }
+ return true;
+}
+
+SkMask::Format SkTableMaskFilter::getFormat() {
+ return SkMask::kA8_Format;
+}
+
+void SkTableMaskFilter::flatten(SkFlattenableWriteBuffer& wb) {
+ this->INHERITED::flatten(wb);
+ wb.writePad(fTable, 256);
+}
+
+SkTableMaskFilter::SkTableMaskFilter(SkFlattenableReadBuffer& rb)
+ : INHERITED(rb) {
+ rb.read(fTable, 256);
+}
+
+SkFlattenable* SkTableMaskFilter::Factory(SkFlattenableReadBuffer& rb) {
+ return SkNEW_ARGS(SkTableMaskFilter, (rb));
+}
+
+SkFlattenable::Factory SkTableMaskFilter::getFactory() {
+ return SkTableMaskFilter::Factory;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkTableMaskFilter::MakeGammaTable(uint8_t table[256], SkScalar gamma) {
+ float x = 0;
+ const float dx = 1 / 255.0f;
+ for (int i = 0; i < 256; i++) {
+ table[i] = SkPin32(SkScalarRound(powf(x, gamma) * 255), 0, 255);
+ x += dx;
+ }
+}
+
+void SkTableMaskFilter::MakeClipTable(uint8_t table[256], uint8_t min,
+ uint8_t max) {
+ if (0 == max) {
+ max = 1;
+ }
+ if (min >= max) {
+ min = max - 1;
+ }
+ SkASSERT(min < max);
+
+ SkFixed scale = (1 << 16) * 255 / (max - min);
+ memset(table, 0, min + 1);
+ for (int i = min + 1; i < max; i++) {
+ int value = SkFixedRound(scale * (i - min));
+ SkASSERT(value <= 255);
+ table[i] = value;
+ }
+ memset(table + max, 255, 256 - max);
+
+#if 0
+ int j;
+ for (j = 0; j < 256; j++) {
+ if (table[j]) {
+ break;
+ }
+ }
+ SkDebugf("%d %d start [%d]", min, max, j);
+ for (; j < 256; j++) {
+ SkDebugf(" %d", table[j]);
+ }
+ SkDebugf("\n\n");
+#endif
+}
+
