blob: 6bcc1ba9dbba293d7f796da97a0dffc5be5e6f3b [file] [log] [blame]
/*
* 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 "SkGradientShaderPriv.h"
#include "SkLinearGradient.h"
#include "SkRadialGradient.h"
#include "SkTwoPointRadialGradient.h"
#include "SkTwoPointConicalGradient.h"
#include "SkSweepGradient.h"
SkGradientShaderBase::SkGradientShaderBase(const SkColor colors[], const SkScalar pos[],
int colorCount, SkShader::TileMode mode, SkUnitMapper* mapper) {
SkASSERT(colorCount > 1);
fCacheAlpha = 256; // init to a value that paint.getAlpha() can't return
fMapper = mapper;
SkSafeRef(mapper);
SkASSERT((unsigned)mode < SkShader::kTileModeCount);
SkASSERT(SkShader::kTileModeCount == SK_ARRAY_COUNT(gTileProcs));
fTileMode = mode;
fTileProc = gTileProcs[mode];
fCache16 = fCache16Storage = NULL;
fCache32 = NULL;
fCache32PixelRef = NULL;
/* Note: we let the caller skip the first and/or last position.
i.e. pos[0] = 0.3, pos[1] = 0.7
In these cases, we insert dummy entries to ensure that the final data
will be bracketed by [0, 1].
i.e. our_pos[0] = 0, our_pos[1] = 0.3, our_pos[2] = 0.7, our_pos[3] = 1
Thus colorCount (the caller's value, and fColorCount (our value) may
differ by up to 2. In the above example:
colorCount = 2
fColorCount = 4
*/
fColorCount = colorCount;
// check if we need to add in dummy start and/or end position/colors
bool dummyFirst = false;
bool dummyLast = false;
if (pos) {
dummyFirst = pos[0] != 0;
dummyLast = pos[colorCount - 1] != SK_Scalar1;
fColorCount += dummyFirst + dummyLast;
}
if (fColorCount > kColorStorageCount) {
size_t size = sizeof(SkColor) + sizeof(Rec);
fOrigColors = reinterpret_cast<SkColor*>(
sk_malloc_throw(size * fColorCount));
}
else {
fOrigColors = fStorage;
}
// Now copy over the colors, adding the dummies as needed
{
SkColor* origColors = fOrigColors;
if (dummyFirst) {
*origColors++ = colors[0];
}
memcpy(origColors, colors, colorCount * sizeof(SkColor));
if (dummyLast) {
origColors += colorCount;
*origColors = colors[colorCount - 1];
}
}
fRecs = (Rec*)(fOrigColors + fColorCount);
if (fColorCount > 2) {
Rec* recs = fRecs;
recs->fPos = 0;
// recs->fScale = 0; // unused;
recs += 1;
if (pos) {
/* We need to convert the user's array of relative positions into
fixed-point positions and scale factors. We need these results
to be strictly monotonic (no two values equal or out of order).
Hence this complex loop that just jams a zero for the scale
value if it sees a segment out of order, and it assures that
we start at 0 and end at 1.0
*/
SkFixed prev = 0;
int startIndex = dummyFirst ? 0 : 1;
int count = colorCount + dummyLast;
for (int i = startIndex; i < count; i++) {
// force the last value to be 1.0
SkFixed curr;
if (i == colorCount) { // we're really at the dummyLast
curr = SK_Fixed1;
} else {
curr = SkScalarToFixed(pos[i]);
}
// pin curr withing range
if (curr < 0) {
curr = 0;
} else if (curr > SK_Fixed1) {
curr = SK_Fixed1;
}
recs->fPos = curr;
if (curr > prev) {
recs->fScale = (1 << 24) / (curr - prev);
} else {
recs->fScale = 0; // ignore this segment
}
// get ready for the next value
prev = curr;
recs += 1;
}
} else { // assume even distribution
SkFixed dp = SK_Fixed1 / (colorCount - 1);
SkFixed p = dp;
SkFixed scale = (colorCount - 1) << 8; // (1 << 24) / dp
for (int i = 1; i < colorCount; i++) {
recs->fPos = p;
recs->fScale = scale;
recs += 1;
p += dp;
}
}
}
this->initCommon();
}
SkGradientShaderBase::SkGradientShaderBase(SkFlattenableReadBuffer& buffer) :
INHERITED(buffer) {
fCacheAlpha = 256;
fMapper = buffer.readFlattenableT<SkUnitMapper>();
fCache16 = fCache16Storage = NULL;
fCache32 = NULL;
fCache32PixelRef = NULL;
int colorCount = fColorCount = buffer.getArrayCount();
if (colorCount > kColorStorageCount) {
size_t size = sizeof(SkColor) + sizeof(SkPMColor) + sizeof(Rec);
fOrigColors = (SkColor*)sk_malloc_throw(size * colorCount);
} else {
fOrigColors = fStorage;
}
buffer.readColorArray(fOrigColors);
fTileMode = (TileMode)buffer.readUInt();
fTileProc = gTileProcs[fTileMode];
fRecs = (Rec*)(fOrigColors + colorCount);
if (colorCount > 2) {
Rec* recs = fRecs;
recs[0].fPos = 0;
for (int i = 1; i < colorCount; i++) {
recs[i].fPos = buffer.readInt();
recs[i].fScale = buffer.readUInt();
}
}
buffer.readMatrix(&fPtsToUnit);
this->initCommon();
}
SkGradientShaderBase::~SkGradientShaderBase() {
if (fCache16Storage) {
sk_free(fCache16Storage);
}
SkSafeUnref(fCache32PixelRef);
if (fOrigColors != fStorage) {
sk_free(fOrigColors);
}
SkSafeUnref(fMapper);
}
void SkGradientShaderBase::initCommon() {
fFlags = 0;
unsigned colorAlpha = 0xFF;
for (int i = 0; i < fColorCount; i++) {
colorAlpha &= SkColorGetA(fOrigColors[i]);
}
fColorsAreOpaque = colorAlpha == 0xFF;
}
void SkGradientShaderBase::flatten(SkFlattenableWriteBuffer& buffer) const {
this->INHERITED::flatten(buffer);
buffer.writeFlattenable(fMapper);
buffer.writeColorArray(fOrigColors, fColorCount);
buffer.writeUInt(fTileMode);
if (fColorCount > 2) {
Rec* recs = fRecs;
for (int i = 1; i < fColorCount; i++) {
buffer.writeInt(recs[i].fPos);
buffer.writeUInt(recs[i].fScale);
}
}
buffer.writeMatrix(fPtsToUnit);
}
bool SkGradientShaderBase::isOpaque() const {
return fColorsAreOpaque;
}
bool SkGradientShaderBase::setContext(const SkBitmap& device,
const SkPaint& paint,
const SkMatrix& matrix) {
if (!this->INHERITED::setContext(device, paint, matrix)) {
return false;
}
const SkMatrix& inverse = this->getTotalInverse();
if (!fDstToIndex.setConcat(fPtsToUnit, inverse)) {
return false;
}
fDstToIndexProc = fDstToIndex.getMapXYProc();
fDstToIndexClass = (uint8_t)SkShader::ComputeMatrixClass(fDstToIndex);
// now convert our colors in to PMColors
unsigned paintAlpha = this->getPaintAlpha();
fFlags = this->INHERITED::getFlags();
if (fColorsAreOpaque && paintAlpha == 0xFF) {
fFlags |= kOpaqueAlpha_Flag;
}
// we can do span16 as long as our individual colors are opaque,
// regardless of the paint's alpha
if (fColorsAreOpaque) {
fFlags |= kHasSpan16_Flag;
}
this->setCacheAlpha(paintAlpha);
return true;
}
void SkGradientShaderBase::setCacheAlpha(U8CPU alpha) const {
// if the new alpha differs from the previous time we were called, inval our cache
// this will trigger the cache to be rebuilt.
// we don't care about the first time, since the cache ptrs will already be NULL
if (fCacheAlpha != alpha) {
fCache16 = NULL; // inval the cache
fCache32 = NULL; // inval the cache
fCacheAlpha = alpha; // record the new alpha
// inform our subclasses
if (fCache32PixelRef) {
fCache32PixelRef->notifyPixelsChanged();
}
}
}
#define Fixed_To_Dot8(x) (((x) + 0x80) >> 8)
/** We take the original colors, not our premultiplied PMColors, since we can
build a 16bit table as long as the original colors are opaque, even if the
paint specifies a non-opaque alpha.
*/
void SkGradientShaderBase::Build16bitCache(uint16_t cache[], SkColor c0, SkColor c1,
int count) {
SkASSERT(count > 1);
SkASSERT(SkColorGetA(c0) == 0xFF);
SkASSERT(SkColorGetA(c1) == 0xFF);
SkFixed r = SkColorGetR(c0);
SkFixed g = SkColorGetG(c0);
SkFixed b = SkColorGetB(c0);
SkFixed dr = SkIntToFixed(SkColorGetR(c1) - r) / (count - 1);
SkFixed dg = SkIntToFixed(SkColorGetG(c1) - g) / (count - 1);
SkFixed db = SkIntToFixed(SkColorGetB(c1) - b) / (count - 1);
r = SkIntToFixed(r) + 0x8000;
g = SkIntToFixed(g) + 0x8000;
b = SkIntToFixed(b) + 0x8000;
do {
unsigned rr = r >> 16;
unsigned gg = g >> 16;
unsigned bb = b >> 16;
cache[0] = SkPackRGB16(SkR32ToR16(rr), SkG32ToG16(gg), SkB32ToB16(bb));
cache[kCache16Count] = SkDitherPack888ToRGB16(rr, gg, bb);
cache += 1;
r += dr;
g += dg;
b += db;
} while (--count != 0);
}
/*
* 2x2 dither a fixed-point color component (8.16) down to 8, matching the
* semantics of how we 2x2 dither 32->16
*/
static inline U8CPU dither_fixed_to_8(SkFixed n) {
n >>= 8;
return ((n << 1) - ((n >> 8 << 8) | (n >> 8))) >> 8;
}
/*
* For dithering with premultiply, we want to ceiling the alpha component,
* to ensure that it is always >= any color component.
*/
static inline U8CPU dither_ceil_fixed_to_8(SkFixed n) {
n >>= 8;
return ((n << 1) - (n | (n >> 8))) >> 8;
}
void SkGradientShaderBase::Build32bitCache(SkPMColor cache[], SkColor c0, SkColor c1,
int count, U8CPU paintAlpha) {
SkASSERT(count > 1);
// need to apply paintAlpha to our two endpoints
SkFixed a = SkMulDiv255Round(SkColorGetA(c0), paintAlpha);
SkFixed da;
{
int tmp = SkMulDiv255Round(SkColorGetA(c1), paintAlpha);
da = SkIntToFixed(tmp - a) / (count - 1);
}
SkFixed r = SkColorGetR(c0);
SkFixed g = SkColorGetG(c0);
SkFixed b = SkColorGetB(c0);
SkFixed dr = SkIntToFixed(SkColorGetR(c1) - r) / (count - 1);
SkFixed dg = SkIntToFixed(SkColorGetG(c1) - g) / (count - 1);
SkFixed db = SkIntToFixed(SkColorGetB(c1) - b) / (count - 1);
a = SkIntToFixed(a) + 0x8000;
r = SkIntToFixed(r) + 0x8000;
g = SkIntToFixed(g) + 0x8000;
b = SkIntToFixed(b) + 0x8000;
do {
cache[0] = SkPremultiplyARGBInline(a >> 16, r >> 16, g >> 16, b >> 16);
cache[kCache32Count] =
SkPremultiplyARGBInline(dither_ceil_fixed_to_8(a),
dither_fixed_to_8(r),
dither_fixed_to_8(g),
dither_fixed_to_8(b));
cache += 1;
a += da;
r += dr;
g += dg;
b += db;
} while (--count != 0);
}
static inline int SkFixedToFFFF(SkFixed x) {
SkASSERT((unsigned)x <= SK_Fixed1);
return x - (x >> 16);
}
static inline U16CPU bitsTo16(unsigned x, const unsigned bits) {
SkASSERT(x < (1U << bits));
if (6 == bits) {
return (x << 10) | (x << 4) | (x >> 2);
}
if (8 == bits) {
return (x << 8) | x;
}
sk_throw();
return 0;
}
/** We duplicate the last value in each half of the cache so that
interpolation doesn't have to special-case being at the last point.
*/
static void complete_16bit_cache(uint16_t* cache, int stride) {
cache[stride - 1] = cache[stride - 2];
cache[2 * stride - 1] = cache[2 * stride - 2];
}
const uint16_t* SkGradientShaderBase::getCache16() const {
if (fCache16 == NULL) {
// double the count for dither entries
const int entryCount = kCache16Count * 2;
const size_t allocSize = sizeof(uint16_t) * entryCount;
if (fCache16Storage == NULL) { // set the storage and our working ptr
fCache16Storage = (uint16_t*)sk_malloc_throw(allocSize);
}
fCache16 = fCache16Storage;
if (fColorCount == 2) {
Build16bitCache(fCache16, fOrigColors[0], fOrigColors[1],
kGradient16Length);
} else {
Rec* rec = fRecs;
int prevIndex = 0;
for (int i = 1; i < fColorCount; i++) {
int nextIndex = SkFixedToFFFF(rec[i].fPos) >> kCache16Shift;
SkASSERT(nextIndex < kCache16Count);
if (nextIndex > prevIndex)
Build16bitCache(fCache16 + prevIndex, fOrigColors[i-1], fOrigColors[i], nextIndex - prevIndex + 1);
prevIndex = nextIndex;
}
// one extra space left over at the end for complete_16bit_cache()
SkASSERT(prevIndex == kGradient16Length - 1);
}
if (fMapper) {
fCache16Storage = (uint16_t*)sk_malloc_throw(allocSize);
uint16_t* linear = fCache16; // just computed linear data
uint16_t* mapped = fCache16Storage; // storage for mapped data
SkUnitMapper* map = fMapper;
for (int i = 0; i < kGradient16Length; i++) {
int index = map->mapUnit16(bitsTo16(i, kCache16Bits)) >> kCache16Shift;
mapped[i] = linear[index];
mapped[i + kCache16Count] = linear[index + kCache16Count];
}
sk_free(fCache16);
fCache16 = fCache16Storage;
}
complete_16bit_cache(fCache16, kCache16Count);
}
return fCache16;
}
/** We duplicate the last value in each half of the cache so that
interpolation doesn't have to special-case being at the last point.
*/
static void complete_32bit_cache(SkPMColor* cache, int stride) {
cache[stride - 1] = cache[stride - 2];
cache[2 * stride - 1] = cache[2 * stride - 2];
}
const SkPMColor* SkGradientShaderBase::getCache32() const {
if (fCache32 == NULL) {
// double the count for dither entries
const int entryCount = kCache32Count * 2;
const size_t allocSize = sizeof(SkPMColor) * entryCount;
if (NULL == fCache32PixelRef) {
fCache32PixelRef = SkNEW_ARGS(SkMallocPixelRef,
(NULL, allocSize, NULL));
}
fCache32 = (SkPMColor*)fCache32PixelRef->getAddr();
if (fColorCount == 2) {
Build32bitCache(fCache32, fOrigColors[0], fOrigColors[1],
kGradient32Length, fCacheAlpha);
} else {
Rec* rec = fRecs;
int prevIndex = 0;
for (int i = 1; i < fColorCount; i++) {
int nextIndex = SkFixedToFFFF(rec[i].fPos) >> kCache32Shift;
SkASSERT(nextIndex < kGradient32Length);
if (nextIndex > prevIndex)
Build32bitCache(fCache32 + prevIndex, fOrigColors[i-1],
fOrigColors[i],
nextIndex - prevIndex + 1, fCacheAlpha);
prevIndex = nextIndex;
}
SkASSERT(prevIndex == kGradient32Length - 1);
}
if (fMapper) {
SkMallocPixelRef* newPR = SkNEW_ARGS(SkMallocPixelRef,
(NULL, allocSize, NULL));
SkPMColor* linear = fCache32; // just computed linear data
SkPMColor* mapped = (SkPMColor*)newPR->getAddr(); // storage for mapped data
SkUnitMapper* map = fMapper;
for (int i = 0; i < kGradient32Length; i++) {
int index = map->mapUnit16((i << 8) | i) >> 8;
mapped[i] = linear[index];
mapped[i + kCache32Count] = linear[index + kCache32Count];
}
fCache32PixelRef->unref();
fCache32PixelRef = newPR;
fCache32 = (SkPMColor*)newPR->getAddr();
}
complete_32bit_cache(fCache32, kCache32Count);
}
return fCache32;
}
/*
* Because our caller might rebuild the same (logically the same) gradient
* over and over, we'd like to return exactly the same "bitmap" if possible,
* allowing the client to utilize a cache of our bitmap (e.g. with a GPU).
* To do that, we maintain a private cache of built-bitmaps, based on our
* colors and positions. Note: we don't try to flatten the fMapper, so if one
* is present, we skip the cache for now.
*/
void SkGradientShaderBase::getGradientTableBitmap(SkBitmap* bitmap) const {
// our caller assumes no external alpha, so we ensure that our cache is
// built with 0xFF
this->setCacheAlpha(0xFF);
// don't have a way to put the mapper into our cache-key yet
if (fMapper) {
// force our cahce32pixelref to be built
(void)this->getCache32();
bitmap->setConfig(SkBitmap::kARGB_8888_Config, kGradient32Length, 1);
bitmap->setPixelRef(fCache32PixelRef);
return;
}
// build our key: [numColors + colors[] + {positions[]} ]
int count = 1 + fColorCount;
if (fColorCount > 2) {
count += fColorCount - 1; // fRecs[].fPos
}
SkAutoSTMalloc<16, int32_t> storage(count);
int32_t* buffer = storage.get();
*buffer++ = fColorCount;
memcpy(buffer, fOrigColors, fColorCount * sizeof(SkColor));
buffer += fColorCount;
if (fColorCount > 2) {
for (int i = 1; i < fColorCount; i++) {
*buffer++ = fRecs[i].fPos;
}
}
SkASSERT(buffer - storage.get() == count);
///////////////////////////////////
SK_DECLARE_STATIC_MUTEX(gMutex);
static SkBitmapCache* gCache;
// each cache cost 1K of RAM, since each bitmap will be 1x256 at 32bpp
static const int MAX_NUM_CACHED_GRADIENT_BITMAPS = 32;
SkAutoMutexAcquire ama(gMutex);
if (NULL == gCache) {
gCache = SkNEW_ARGS(SkBitmapCache, (MAX_NUM_CACHED_GRADIENT_BITMAPS));
}
size_t size = count * sizeof(int32_t);
if (!gCache->find(storage.get(), size, bitmap)) {
// force our cahce32pixelref to be built
(void)this->getCache32();
// Only expose the linear section of the cache; don't let the caller
// know about the padding at the end to make interpolation faster.
bitmap->setConfig(SkBitmap::kARGB_8888_Config, kGradient32Length, 1);
bitmap->setPixelRef(fCache32PixelRef);
gCache->add(storage.get(), size, *bitmap);
}
}
void SkGradientShaderBase::commonAsAGradient(GradientInfo* info) const {
if (info) {
if (info->fColorCount >= fColorCount) {
if (info->fColors) {
memcpy(info->fColors, fOrigColors,
fColorCount * sizeof(SkColor));
}
if (info->fColorOffsets) {
if (fColorCount == 2) {
info->fColorOffsets[0] = 0;
info->fColorOffsets[1] = SK_Scalar1;
} else if (fColorCount > 2) {
for (int i = 0; i < fColorCount; i++)
info->fColorOffsets[i] = SkFixedToScalar(fRecs[i].fPos);
}
}
}
info->fColorCount = fColorCount;
info->fTileMode = fTileMode;
}
}
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
#include "SkEmptyShader.h"
// assumes colors is SkColor* and pos is SkScalar*
#define EXPAND_1_COLOR(count) \
SkColor tmp[2]; \
do { \
if (1 == count) { \
tmp[0] = tmp[1] = colors[0]; \
colors = tmp; \
pos = NULL; \
count = 2; \
} \
} while (0)
SkShader* SkGradientShader::CreateLinear(const SkPoint pts[2],
const SkColor colors[],
const SkScalar pos[], int colorCount,
SkShader::TileMode mode,
SkUnitMapper* mapper) {
if (NULL == pts || NULL == colors || colorCount < 1) {
return NULL;
}
EXPAND_1_COLOR(colorCount);
return SkNEW_ARGS(SkLinearGradient,
(pts, colors, pos, colorCount, mode, mapper));
}
SkShader* SkGradientShader::CreateRadial(const SkPoint& center, SkScalar radius,
const SkColor colors[],
const SkScalar pos[], int colorCount,
SkShader::TileMode mode,
SkUnitMapper* mapper) {
if (radius <= 0 || NULL == colors || colorCount < 1) {
return NULL;
}
EXPAND_1_COLOR(colorCount);
return SkNEW_ARGS(SkRadialGradient,
(center, radius, colors, pos, colorCount, mode, mapper));
}
SkShader* SkGradientShader::CreateTwoPointRadial(const SkPoint& start,
SkScalar startRadius,
const SkPoint& end,
SkScalar endRadius,
const SkColor colors[],
const SkScalar pos[],
int colorCount,
SkShader::TileMode mode,
SkUnitMapper* mapper) {
if (startRadius < 0 || endRadius < 0 || NULL == colors || colorCount < 1) {
return NULL;
}
EXPAND_1_COLOR(colorCount);
return SkNEW_ARGS(SkTwoPointRadialGradient,
(start, startRadius, end, endRadius, colors, pos,
colorCount, mode, mapper));
}
SkShader* SkGradientShader::CreateTwoPointConical(const SkPoint& start,
SkScalar startRadius,
const SkPoint& end,
SkScalar endRadius,
const SkColor colors[],
const SkScalar pos[],
int colorCount,
SkShader::TileMode mode,
SkUnitMapper* mapper) {
if (startRadius < 0 || endRadius < 0 || NULL == colors || colorCount < 1) {
return NULL;
}
if (start == end && startRadius == endRadius) {
return SkNEW(SkEmptyShader);
}
EXPAND_1_COLOR(colorCount);
return SkNEW_ARGS(SkTwoPointConicalGradient,
(start, startRadius, end, endRadius, colors, pos,
colorCount, mode, mapper));
}
SkShader* SkGradientShader::CreateSweep(SkScalar cx, SkScalar cy,
const SkColor colors[],
const SkScalar pos[],
int count, SkUnitMapper* mapper) {
if (NULL == colors || count < 1) {
return NULL;
}
EXPAND_1_COLOR(count);
return SkNEW_ARGS(SkSweepGradient, (cx, cy, colors, pos, count, mapper));
}
SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkGradientShader)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkLinearGradient)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkRadialGradient)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkSweepGradient)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkTwoPointRadialGradient)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkTwoPointConicalGradient)
SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END
///////////////////////////////////////////////////////////////////////////////
#if SK_SUPPORT_GPU
#include "effects/GrTextureStripAtlas.h"
#include "SkGr.h"
GrGLGradientStage::GrGLGradientStage(const GrProgramStageFactory& factory)
: INHERITED(factory)
, fCachedYCoord(GR_ScalarMax)
, fFSYUni(GrGLUniformManager::kInvalidUniformHandle) { }
GrGLGradientStage::~GrGLGradientStage() { }
void GrGLGradientStage::setupVariables(GrGLShaderBuilder* builder) {
fFSYUni = builder->addUniform(GrGLShaderBuilder::kFragment_ShaderType,
kFloat_GrSLType, "GradientYCoordFS");
}
void GrGLGradientStage::setData(const GrGLUniformManager& uman,
const GrCustomStage& stage,
const GrRenderTarget*,
int stageNum) {
GrScalar yCoord = static_cast<const GrGradientEffect&>(stage).getYCoord();
if (yCoord != fCachedYCoord) {
uman.set1f(fFSYUni, yCoord);
fCachedYCoord = yCoord;
}
}
void GrGLGradientStage::emitColorLookup(GrGLShaderBuilder* builder,
const char* tName,
const char* outputColor,
const char* samplerName) {
builder->fSampleCoords.printf("vec2(%s, %s)", tName,
builder->getUniformVariable(fFSYUni).c_str());
builder->fComplexCoord = true;
builder->emitDefaultFetch(outputColor, samplerName);
}
/////////////////////////////////////////////////////////////////////
GrGradientEffect::GrGradientEffect(GrContext* ctx,
const SkGradientShaderBase& shader,
GrSamplerState* sampler)
: fTexture (NULL)
, fUseTexture (true) {
// TODO: check for simple cases where we don't need a texture:
//GradientInfo info;
//shader.asAGradient(&info);
//if (info.fColorCount == 2) { ...
SkBitmap bitmap;
shader.getGradientTableBitmap(&bitmap);
GrTextureStripAtlas::Desc desc;
desc.fWidth = bitmap.width();
desc.fHeight = 32;
desc.fRowHeight = bitmap.height();
desc.fContext = ctx;
desc.fConfig = SkBitmapConfig2GrPixelConfig(bitmap.config());
fAtlas = GrTextureStripAtlas::GetAtlas(desc);
GrAssert(NULL != fAtlas);
fRow = fAtlas->lockRow(bitmap);
if (-1 != fRow) {
fYCoord = fAtlas->getYOffset(fRow) + GR_ScalarHalf *
fAtlas->getVerticalScaleFactor();
fTexture = fAtlas->getTexture();
} else {
fTexture = GrLockCachedBitmapTexture(ctx, bitmap, sampler->textureParams());
SkSafeRef(fTexture);
fYCoord = GR_ScalarHalf;
// Unlock immediately, this is not great, but we don't have a way of
// knowing when else to unlock it currently, so it may get purged from
// the cache, but it'll still be ref'd until it's no longer being used.
GrUnlockCachedBitmapTexture(fTexture);
}
}
GrGradientEffect::~GrGradientEffect() {
if (this->useAtlas()) {
fAtlas->unlockRow(fRow);
} else {
SkSafeUnref(fTexture);
}
}
unsigned int GrGradientEffect::numTextures() const {
return fUseTexture ? 1 : 0;
}
GrTexture* GrGradientEffect::texture(unsigned int index)
const {
GrAssert(fUseTexture && 0 == index);
return fTexture;
}
int GrGradientEffect::RandomGradientParams(SkRandom* random,
SkColor colors[],
SkScalar** stops,
SkShader::TileMode* tm) {
int outColors = random->nextRangeU(1, kMaxRandomGradientColors);
// if one color, omit stops, otherwise randomly decide whether or not to
if (outColors == 1 || (outColors >= 2 && random->nextBool())) {
*stops = NULL;
}
GrScalar stop = 0.f;
for (int i = 0; i < outColors; ++i) {
colors[i] = random->nextU();
if (NULL != *stops) {
(*stops)[i] = stop;
stop = i < outColors - 1 ? stop + random->nextUScalar1() * (1.f - stop) : 1.f;
}
}
*tm = static_cast<SkShader::TileMode>(random->nextULessThan(SkShader::kTileModeCount));
return outColors;
}
#endif