/*
* 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 "SkBlitter.h"
#include "SkAntiRun.h"
#include "SkColor.h"
#include "SkColorFilter.h"
#include "SkCoreBlitters.h"
#include "SkFilterShader.h"
#include "SkReadBuffer.h"
#include "SkWriteBuffer.h"
#include "SkMask.h"
#include "SkMaskFilter.h"
#include "SkString.h"
#include "SkTLazy.h"
#include "SkUtils.h"
#include "SkXfermode.h"
SkBlitter::~SkBlitter() {}
bool SkBlitter::isNullBlitter() const { return false; }
bool SkBlitter::resetShaderContext(const SkShader::ContextRec&) {
return true;
}
SkShader::Context* SkBlitter::getShaderContext() const {
return NULL;
}
const SkBitmap* SkBlitter::justAnOpaqueColor(uint32_t* value) {
return NULL;
}
void SkBlitter::blitH(int x, int y, int width) {
SkDEBUGFAIL("unimplemented");
}
void SkBlitter::blitAntiH(int x, int y, const SkAlpha antialias[],
const int16_t runs[]) {
SkDEBUGFAIL("unimplemented");
}
void SkBlitter::blitV(int x, int y, int height, SkAlpha alpha) {
if (alpha == 255) {
this->blitRect(x, y, 1, height);
} else {
int16_t runs[2];
runs[0] = 1;
runs[1] = 0;
while (--height >= 0) {
this->blitAntiH(x, y++, &alpha, runs);
}
}
}
void SkBlitter::blitRect(int x, int y, int width, int height) {
SkASSERT(width > 0);
while (--height >= 0) {
this->blitH(x, y++, width);
}
}
/// Default implementation doesn't check for any easy optimizations
/// such as alpha == 0 or 255; also uses blitV(), which some subclasses
/// may not support.
void SkBlitter::blitAntiRect(int x, int y, int width, int height,
SkAlpha leftAlpha, SkAlpha rightAlpha) {
this->blitV(x++, y, height, leftAlpha);
if (width > 0) {
this->blitRect(x, y, width, height);
x += width;
}
this->blitV(x, y, height, rightAlpha);
}
//////////////////////////////////////////////////////////////////////////////
static inline void bits_to_runs(SkBlitter* blitter, int x, int y,
const uint8_t bits[],
U8CPU left_mask, int rowBytes,
U8CPU right_mask) {
int inFill = 0;
int pos = 0;
while (--rowBytes >= 0) {
unsigned b = *bits++ & left_mask;
if (rowBytes == 0) {
b &= right_mask;
}
for (unsigned test = 0x80; test != 0; test >>= 1) {
if (b & test) {
if (!inFill) {
pos = x;
inFill = true;
}
} else {
if (inFill) {
blitter->blitH(pos, y, x - pos);
inFill = false;
}
}
x += 1;
}
left_mask = 0xFF;
}
// final cleanup
if (inFill) {
blitter->blitH(pos, y, x - pos);
}
}
void SkBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {
SkASSERT(mask.fBounds.contains(clip));
if (mask.fFormat == SkMask::kBW_Format) {
int cx = clip.fLeft;
int cy = clip.fTop;
int maskLeft = mask.fBounds.fLeft;
int mask_rowBytes = mask.fRowBytes;
int height = clip.height();
const uint8_t* bits = mask.getAddr1(cx, cy);
if (cx == maskLeft && clip.fRight == mask.fBounds.fRight) {
while (--height >= 0) {
bits_to_runs(this, cx, cy, bits, 0xFF, mask_rowBytes, 0xFF);
bits += mask_rowBytes;
cy += 1;
}
} else {
int left_edge = cx - maskLeft;
SkASSERT(left_edge >= 0);
int rite_edge = clip.fRight - maskLeft;
SkASSERT(rite_edge > left_edge);
int left_mask = 0xFF >> (left_edge & 7);
int rite_mask = 0xFF << (8 - (rite_edge & 7));
int full_runs = (rite_edge >> 3) - ((left_edge + 7) >> 3);
// check for empty right mask, so we don't read off the end (or go slower than we need to)
if (rite_mask == 0) {
SkASSERT(full_runs >= 0);
full_runs -= 1;
rite_mask = 0xFF;
}
if (left_mask == 0xFF) {
full_runs -= 1;
}
// back up manually so we can keep in sync with our byte-aligned src
// have cx reflect our actual starting x-coord
cx -= left_edge & 7;
if (full_runs < 0) {
SkASSERT((left_mask & rite_mask) != 0);
while (--height >= 0) {
bits_to_runs(this, cx, cy, bits, left_mask, 1, rite_mask);
bits += mask_rowBytes;
cy += 1;
}
} else {
while (--height >= 0) {
bits_to_runs(this, cx, cy, bits, left_mask, full_runs + 2, rite_mask);
bits += mask_rowBytes;
cy += 1;
}
}
}
} else {
int width = clip.width();
SkAutoSTMalloc<64, int16_t> runStorage(width + 1);
int16_t* runs = runStorage.get();
const uint8_t* aa = mask.getAddr8(clip.fLeft, clip.fTop);
sk_memset16((uint16_t*)runs, 1, width);
runs[width] = 0;
int height = clip.height();
int y = clip.fTop;
while (--height >= 0) {
this->blitAntiH(clip.fLeft, y, aa, runs);
aa += mask.fRowBytes;
y += 1;
}
}
}
/////////////////////// these guys are not virtual, just a helpers
void SkBlitter::blitMaskRegion(const SkMask& mask, const SkRegion& clip) {
if (clip.quickReject(mask.fBounds)) {
return;
}
SkRegion::Cliperator clipper(clip, mask.fBounds);
while (!clipper.done()) {
const SkIRect& cr = clipper.rect();
this->blitMask(mask, cr);
clipper.next();
}
}
void SkBlitter::blitRectRegion(const SkIRect& rect, const SkRegion& clip) {
SkRegion::Cliperator clipper(clip, rect);
while (!clipper.done()) {
const SkIRect& cr = clipper.rect();
this->blitRect(cr.fLeft, cr.fTop, cr.width(), cr.height());
clipper.next();
}
}
void SkBlitter::blitRegion(const SkRegion& clip) {
SkRegion::Iterator iter(clip);
while (!iter.done()) {
const SkIRect& cr = iter.rect();
this->blitRect(cr.fLeft, cr.fTop, cr.width(), cr.height());
iter.next();
}
}
///////////////////////////////////////////////////////////////////////////////
void SkNullBlitter::blitH(int x, int y, int width) {}
void SkNullBlitter::blitAntiH(int x, int y, const SkAlpha antialias[],
const int16_t runs[]) {}
void SkNullBlitter::blitV(int x, int y, int height, SkAlpha alpha) {}
void SkNullBlitter::blitRect(int x, int y, int width, int height) {}
void SkNullBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {}
const SkBitmap* SkNullBlitter::justAnOpaqueColor(uint32_t* value) {
return NULL;
}
bool SkNullBlitter::isNullBlitter() const { return true; }
///////////////////////////////////////////////////////////////////////////////
static int compute_anti_width(const int16_t runs[]) {
int width = 0;
for (;;) {
int count = runs[0];
SkASSERT(count >= 0);
if (count == 0) {
break;
}
width += count;
runs += count;
}
return width;
}
static inline bool y_in_rect(int y, const SkIRect& rect) {
return (unsigned)(y - rect.fTop) < (unsigned)rect.height();
}
static inline bool x_in_rect(int x, const SkIRect& rect) {
return (unsigned)(x - rect.fLeft) < (unsigned)rect.width();
}
void SkRectClipBlitter::blitH(int left, int y, int width) {
SkASSERT(width > 0);
if (!y_in_rect(y, fClipRect)) {
return;
}
int right = left + width;
if (left < fClipRect.fLeft) {
left = fClipRect.fLeft;
}
if (right > fClipRect.fRight) {
right = fClipRect.fRight;
}
width = right - left;
if (width > 0) {
fBlitter->blitH(left, y, width);
}
}
void SkRectClipBlitter::blitAntiH(int left, int y, const SkAlpha aa[],
const int16_t runs[]) {
if (!y_in_rect(y, fClipRect) || left >= fClipRect.fRight) {
return;
}
int x0 = left;
int x1 = left + compute_anti_width(runs);
if (x1 <= fClipRect.fLeft) {
return;
}
SkASSERT(x0 < x1);
if (x0 < fClipRect.fLeft) {
int dx = fClipRect.fLeft - x0;
SkAlphaRuns::BreakAt((int16_t*)runs, (uint8_t*)aa, dx);
runs += dx;
aa += dx;
x0 = fClipRect.fLeft;
}
SkASSERT(x0 < x1 && runs[x1 - x0] == 0);
if (x1 > fClipRect.fRight) {
x1 = fClipRect.fRight;
SkAlphaRuns::BreakAt((int16_t*)runs, (uint8_t*)aa, x1 - x0);
((int16_t*)runs)[x1 - x0] = 0;
}
SkASSERT(x0 < x1 && runs[x1 - x0] == 0);
SkASSERT(compute_anti_width(runs) == x1 - x0);
fBlitter->blitAntiH(x0, y, aa, runs);
}
void SkRectClipBlitter::blitV(int x, int y, int height, SkAlpha alpha) {
SkASSERT(height > 0);
if (!x_in_rect(x, fClipRect)) {
return;
}
int y0 = y;
int y1 = y + height;
if (y0 < fClipRect.fTop) {
y0 = fClipRect.fTop;
}
if (y1 > fClipRect.fBottom) {
y1 = fClipRect.fBottom;
}
if (y0 < y1) {
fBlitter->blitV(x, y0, y1 - y0, alpha);
}
}
void SkRectClipBlitter::blitRect(int left, int y, int width, int height) {
SkIRect r;
r.set(left, y, left + width, y + height);
if (r.intersect(fClipRect)) {
fBlitter->blitRect(r.fLeft, r.fTop, r.width(), r.height());
}
}
void SkRectClipBlitter::blitAntiRect(int left, int y, int width, int height,
SkAlpha leftAlpha, SkAlpha rightAlpha) {
SkIRect r;
// The *true* width of the rectangle blitted is width+2:
r.set(left, y, left + width + 2, y + height);
if (r.intersect(fClipRect)) {
if (r.fLeft != left) {
SkASSERT(r.fLeft > left);
leftAlpha = 255;
}
if (r.fRight != left + width + 2) {
SkASSERT(r.fRight < left + width + 2);
rightAlpha = 255;
}
if (255 == leftAlpha && 255 == rightAlpha) {
fBlitter->blitRect(r.fLeft, r.fTop, r.width(), r.height());
} else if (1 == r.width()) {
if (r.fLeft == left) {
fBlitter->blitV(r.fLeft, r.fTop, r.height(), leftAlpha);
} else {
SkASSERT(r.fLeft == left + width + 1);
fBlitter->blitV(r.fLeft, r.fTop, r.height(), rightAlpha);
}
} else {
fBlitter->blitAntiRect(r.fLeft, r.fTop, r.width() - 2, r.height(),
leftAlpha, rightAlpha);
}
}
}
void SkRectClipBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {
SkASSERT(mask.fBounds.contains(clip));
SkIRect r = clip;
if (r.intersect(fClipRect)) {
fBlitter->blitMask(mask, r);
}
}
const SkBitmap* SkRectClipBlitter::justAnOpaqueColor(uint32_t* value) {
return fBlitter->justAnOpaqueColor(value);
}
///////////////////////////////////////////////////////////////////////////////
void SkRgnClipBlitter::blitH(int x, int y, int width) {
SkRegion::Spanerator span(*fRgn, y, x, x + width);
int left, right;
while (span.next(&left, &right)) {
SkASSERT(left < right);
fBlitter->blitH(left, y, right - left);
}
}
void SkRgnClipBlitter::blitAntiH(int x, int y, const SkAlpha aa[],
const int16_t runs[]) {
int width = compute_anti_width(runs);
SkRegion::Spanerator span(*fRgn, y, x, x + width);
int left, right;
SkDEBUGCODE(const SkIRect& bounds = fRgn->getBounds();)
int prevRite = x;
while (span.next(&left, &right)) {
SkASSERT(x <= left);
SkASSERT(left < right);
SkASSERT(left >= bounds.fLeft && right <= bounds.fRight);
SkAlphaRuns::Break((int16_t*)runs, (uint8_t*)aa, left - x, right - left);
// now zero before left
if (left > prevRite) {
int index = prevRite - x;
((uint8_t*)aa)[index] = 0; // skip runs after right
((int16_t*)runs)[index] = SkToS16(left - prevRite);
}
prevRite = right;
}
if (prevRite > x) {
((int16_t*)runs)[prevRite - x] = 0;
if (x < 0) {
int skip = runs[0];
SkASSERT(skip >= -x);
aa += skip;
runs += skip;
x += skip;
}
fBlitter->blitAntiH(x, y, aa, runs);
}
}
void SkRgnClipBlitter::blitV(int x, int y, int height, SkAlpha alpha) {
SkIRect bounds;
bounds.set(x, y, x + 1, y + height);
SkRegion::Cliperator iter(*fRgn, bounds);
while (!iter.done()) {
const SkIRect& r = iter.rect();
SkASSERT(bounds.contains(r));
fBlitter->blitV(x, r.fTop, r.height(), alpha);
iter.next();
}
}
void SkRgnClipBlitter::blitRect(int x, int y, int width, int height) {
SkIRect bounds;
bounds.set(x, y, x + width, y + height);
SkRegion::Cliperator iter(*fRgn, bounds);
while (!iter.done()) {
const SkIRect& r = iter.rect();
SkASSERT(bounds.contains(r));
fBlitter->blitRect(r.fLeft, r.fTop, r.width(), r.height());
iter.next();
}
}
void SkRgnClipBlitter::blitAntiRect(int x, int y, int width, int height,
SkAlpha leftAlpha, SkAlpha rightAlpha) {
// The *true* width of the rectangle to blit is width + 2
SkIRect bounds;
bounds.set(x, y, x + width + 2, y + height);
SkRegion::Cliperator iter(*fRgn, bounds);
while (!iter.done()) {
const SkIRect& r = iter.rect();
SkASSERT(bounds.contains(r));
SkASSERT(r.fLeft >= x);
SkASSERT(r.fRight <= x + width + 2);
SkAlpha effectiveLeftAlpha = (r.fLeft == x) ? leftAlpha : 255;
SkAlpha effectiveRightAlpha = (r.fRight == x + width + 2) ?
rightAlpha : 255;
if (255 == effectiveLeftAlpha && 255 == effectiveRightAlpha) {
fBlitter->blitRect(r.fLeft, r.fTop, r.width(), r.height());
} else if (1 == r.width()) {
if (r.fLeft == x) {
fBlitter->blitV(r.fLeft, r.fTop, r.height(),
effectiveLeftAlpha);
} else {
SkASSERT(r.fLeft == x + width + 1);
fBlitter->blitV(r.fLeft, r.fTop, r.height(),
effectiveRightAlpha);
}
} else {
fBlitter->blitAntiRect(r.fLeft, r.fTop, r.width() - 2, r.height(),
effectiveLeftAlpha, effectiveRightAlpha);
}
iter.next();
}
}
void SkRgnClipBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {
SkASSERT(mask.fBounds.contains(clip));
SkRegion::Cliperator iter(*fRgn, clip);
const SkIRect& r = iter.rect();
SkBlitter* blitter = fBlitter;
while (!iter.done()) {
blitter->blitMask(mask, r);
iter.next();
}
}
const SkBitmap* SkRgnClipBlitter::justAnOpaqueColor(uint32_t* value) {
return fBlitter->justAnOpaqueColor(value);
}
///////////////////////////////////////////////////////////////////////////////
SkBlitter* SkBlitterClipper::apply(SkBlitter* blitter, const SkRegion* clip,
const SkIRect* ir) {
if (clip) {
const SkIRect& clipR = clip->getBounds();
if (clip->isEmpty() || (ir && !SkIRect::Intersects(clipR, *ir))) {
blitter = &fNullBlitter;
} else if (clip->isRect()) {
if (ir == NULL || !clipR.contains(*ir)) {
fRectBlitter.init(blitter, clipR);
blitter = &fRectBlitter;
}
} else {
fRgnBlitter.init(blitter, clip);
blitter = &fRgnBlitter;
}
}
return blitter;
}
///////////////////////////////////////////////////////////////////////////////
#include "SkColorShader.h"
#include "SkColorPriv.h"
class Sk3DShader : public SkShader {
public:
Sk3DShader(SkShader* proxy) : fProxy(proxy) {
SkSafeRef(proxy);
}
virtual ~Sk3DShader() {
SkSafeUnref(fProxy);
}
virtual size_t contextSize() const SK_OVERRIDE {
size_t size = sizeof(Sk3DShaderContext);
if (fProxy) {
size += fProxy->contextSize();
}
return size;
}
virtual Context* onCreateContext(const ContextRec& rec, void* storage) const SK_OVERRIDE {
SkShader::Context* proxyContext = NULL;
if (fProxy) {
char* proxyContextStorage = (char*) storage + sizeof(Sk3DShaderContext);
proxyContext = fProxy->createContext(rec, proxyContextStorage);
if (!proxyContext) {
return NULL;
}
}
return SkNEW_PLACEMENT_ARGS(storage, Sk3DShaderContext, (*this, rec, proxyContext));
}
class Sk3DShaderContext : public SkShader::Context {
public:
// Calls proxyContext's destructor but will NOT free its memory.
Sk3DShaderContext(const Sk3DShader& shader, const ContextRec& rec,
SkShader::Context* proxyContext)
: INHERITED(shader, rec)
, fMask(NULL)
, fProxyContext(proxyContext)
{
if (!fProxyContext) {
fPMColor = SkPreMultiplyColor(rec.fPaint->getColor());
}
}
virtual ~Sk3DShaderContext() {
if (fProxyContext) {
fProxyContext->~Context();
}
}
virtual void set3DMask(const SkMask* mask) SK_OVERRIDE { fMask = mask; }
virtual void shadeSpan(int x, int y, SkPMColor span[], int count) SK_OVERRIDE {
if (fProxyContext) {
fProxyContext->shadeSpan(x, y, span, count);
}
if (fMask == NULL) {
if (fProxyContext == NULL) {
sk_memset32(span, fPMColor, count);
}
return;
}
SkASSERT(fMask->fBounds.contains(x, y));
SkASSERT(fMask->fBounds.contains(x + count - 1, y));
size_t size = fMask->computeImageSize();
const uint8_t* alpha = fMask->getAddr8(x, y);
const uint8_t* mulp = alpha + size;
const uint8_t* addp = mulp + size;
if (fProxyContext) {
for (int i = 0; i < count; i++) {
if (alpha[i]) {
SkPMColor c = span[i];
if (c) {
unsigned a = SkGetPackedA32(c);
unsigned r = SkGetPackedR32(c);
unsigned g = SkGetPackedG32(c);
unsigned b = SkGetPackedB32(c);
unsigned mul = SkAlpha255To256(mulp[i]);
unsigned add = addp[i];
r = SkFastMin32(SkAlphaMul(r, mul) + add, a);
g = SkFastMin32(SkAlphaMul(g, mul) + add, a);
b = SkFastMin32(SkAlphaMul(b, mul) + add, a);
span[i] = SkPackARGB32(a, r, g, b);
}
} else {
span[i] = 0;
}
}
} else { // color
unsigned a = SkGetPackedA32(fPMColor);
unsigned r = SkGetPackedR32(fPMColor);
unsigned g = SkGetPackedG32(fPMColor);
unsigned b = SkGetPackedB32(fPMColor);
for (int i = 0; i < count; i++) {
if (alpha[i]) {
unsigned mul = SkAlpha255To256(mulp[i]);
unsigned add = addp[i];
span[i] = SkPackARGB32( a,
SkFastMin32(SkAlphaMul(r, mul) + add, a),
SkFastMin32(SkAlphaMul(g, mul) + add, a),
SkFastMin32(SkAlphaMul(b, mul) + add, a));
} else {
span[i] = 0;
}
}
}
}
private:
// Unowned.
const SkMask* fMask;
// Memory is unowned, but we need to call the destructor.
SkShader::Context* fProxyContext;
SkPMColor fPMColor;
typedef SkShader::Context INHERITED;
};
#ifndef SK_IGNORE_TO_STRING
virtual void toString(SkString* str) const SK_OVERRIDE {
str->append("Sk3DShader: (");
if (NULL != fProxy) {
str->append("Proxy: ");
fProxy->toString(str);
}
this->INHERITED::toString(str);
str->append(")");
}
#endif
SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Sk3DShader)
protected:
Sk3DShader(SkReadBuffer& buffer) : INHERITED(buffer) {
fProxy = buffer.readShader();
// Leaving this here until we bump the picture version, though this
// shader should never be recorded.
buffer.readColor();
}
virtual void flatten(SkWriteBuffer& buffer) const SK_OVERRIDE {
this->INHERITED::flatten(buffer);
buffer.writeFlattenable(fProxy);
// Leaving this here until we bump the picture version, though this
// shader should never be recorded.
buffer.writeColor(SkColor());
}
private:
SkShader* fProxy;
typedef SkShader INHERITED;
};
class Sk3DBlitter : public SkBlitter {
public:
Sk3DBlitter(SkBlitter* proxy, SkShader::Context* shaderContext)
: fProxy(proxy)
, fShaderContext(shaderContext)
{}
virtual void blitH(int x, int y, int width) {
fProxy->blitH(x, y, width);
}
virtual void blitAntiH(int x, int y, const SkAlpha antialias[],
const int16_t runs[]) {
fProxy->blitAntiH(x, y, antialias, runs);
}
virtual void blitV(int x, int y, int height, SkAlpha alpha) {
fProxy->blitV(x, y, height, alpha);
}
virtual void blitRect(int x, int y, int width, int height) {
fProxy->blitRect(x, y, width, height);
}
virtual void blitMask(const SkMask& mask, const SkIRect& clip) {
if (mask.fFormat == SkMask::k3D_Format) {
fShaderContext->set3DMask(&mask);
((SkMask*)&mask)->fFormat = SkMask::kA8_Format;
fProxy->blitMask(mask, clip);
((SkMask*)&mask)->fFormat = SkMask::k3D_Format;
fShaderContext->set3DMask(NULL);
} else {
fProxy->blitMask(mask, clip);
}
}
private:
// Both pointers are unowned. They will be deleted by SkSmallAllocator.
SkBlitter* fProxy;
SkShader::Context* fShaderContext;
};
///////////////////////////////////////////////////////////////////////////////
#include "SkCoreBlitters.h"
static bool just_solid_color(const SkPaint& paint) {
if (paint.getAlpha() == 0xFF && paint.getColorFilter() == NULL) {
SkShader* shader = paint.getShader();
if (NULL == shader) {
return true;
}
}
return false;
}
/** By analyzing the paint (with an xfermode), we may decide we can take
special action. This enum lists our possible actions
*/
enum XferInterp {
kNormal_XferInterp, // no special interpretation, draw normally
kSrcOver_XferInterp, // draw as if in srcover mode
kSkipDrawing_XferInterp // draw nothing
};
static XferInterp interpret_xfermode(const SkPaint& paint, SkXfermode* xfer,
SkColorType deviceCT) {
SkXfermode::Mode mode;
if (SkXfermode::AsMode(xfer, &mode)) {
switch (mode) {
case SkXfermode::kSrc_Mode:
if (just_solid_color(paint)) {
return kSrcOver_XferInterp;
}
break;
case SkXfermode::kDst_Mode:
return kSkipDrawing_XferInterp;
case SkXfermode::kSrcOver_Mode:
return kSrcOver_XferInterp;
case SkXfermode::kDstOver_Mode:
if (kRGB_565_SkColorType == deviceCT) {
return kSkipDrawing_XferInterp;
}
break;
case SkXfermode::kSrcIn_Mode:
if (kRGB_565_SkColorType == deviceCT &&
just_solid_color(paint)) {
return kSrcOver_XferInterp;
}
break;
case SkXfermode::kDstIn_Mode:
if (just_solid_color(paint)) {
return kSkipDrawing_XferInterp;
}
break;
default:
break;
}
}
return kNormal_XferInterp;
}
SkBlitter* SkBlitter::Choose(const SkBitmap& device,
const SkMatrix& matrix,
const SkPaint& origPaint,
SkTBlitterAllocator* allocator,
bool drawCoverage) {
SkASSERT(allocator != NULL);
SkBlitter* blitter = NULL;
// which check, in case we're being called by a client with a dummy device
// (e.g. they have a bounder that always aborts the draw)
if (kUnknown_SkColorType == device.colorType() ||
(drawCoverage && (kAlpha_8_SkColorType != device.colorType()))) {
blitter = allocator->createT<SkNullBlitter>();
return blitter;
}
SkShader* shader = origPaint.getShader();
SkColorFilter* cf = origPaint.getColorFilter();
SkXfermode* mode = origPaint.getXfermode();
Sk3DShader* shader3D = NULL;
SkTCopyOnFirstWrite<SkPaint> paint(origPaint);
if (origPaint.getMaskFilter() != NULL &&
origPaint.getMaskFilter()->getFormat() == SkMask::k3D_Format) {
shader3D = SkNEW_ARGS(Sk3DShader, (shader));
// we know we haven't initialized lazyPaint yet, so just do it
paint.writable()->setShader(shader3D)->unref();
shader = shader3D;
}
if (NULL != mode) {
switch (interpret_xfermode(*paint, mode, device.colorType())) {
case kSrcOver_XferInterp:
mode = NULL;
paint.writable()->setXfermode(NULL);
break;
case kSkipDrawing_XferInterp:{
blitter = allocator->createT<SkNullBlitter>();
return blitter;
}
default:
break;
}
}
/*
* If the xfermode is CLEAR, then we can completely ignore the installed
* color/shader/colorfilter, and just pretend we're SRC + color==0. This
* will fall into our optimizations for SRC mode.
*/
if (SkXfermode::IsMode(mode, SkXfermode::kClear_Mode)) {
SkPaint* p = paint.writable();
shader = p->setShader(NULL);
cf = p->setColorFilter(NULL);
mode = p->setXfermodeMode(SkXfermode::kSrc_Mode);
p->setColor(0);
}
if (NULL == shader) {
if (mode) {
// xfermodes (and filters) require shaders for our current blitters
shader = SkNEW_ARGS(SkColorShader, (paint->getColor()));
paint.writable()->setShader(shader)->unref();
paint.writable()->setAlpha(0xFF);
} else if (cf) {
// if no shader && no xfermode, we just apply the colorfilter to
// our color and move on.
SkPaint* writablePaint = paint.writable();
writablePaint->setColor(cf->filterColor(paint->getColor()));
writablePaint->setColorFilter(NULL);
cf = NULL;
}
}
if (cf) {
SkASSERT(shader);
shader = SkNEW_ARGS(SkFilterShader, (shader, cf));
paint.writable()->setShader(shader)->unref();
// blitters should ignore the presence/absence of a filter, since
// if there is one, the shader will take care of it.
}
/*
* We create a SkShader::Context object, and store it on the blitter.
*/
SkShader::Context* shaderContext;
if (shader) {
SkShader::ContextRec rec(device, *paint, matrix);
// Try to create the ShaderContext
void* storage = allocator->reserveT<SkShader::Context>(shader->contextSize());
shaderContext = shader->createContext(rec, storage);
if (!shaderContext) {
allocator->freeLast();
blitter = allocator->createT<SkNullBlitter>();
return blitter;
}
SkASSERT(shaderContext);
SkASSERT((void*) shaderContext == storage);
} else {
shaderContext = NULL;
}
switch (device.colorType()) {
case kAlpha_8_SkColorType:
if (drawCoverage) {
SkASSERT(NULL == shader);
SkASSERT(NULL == paint->getXfermode());
blitter = allocator->createT<SkA8_Coverage_Blitter>(device, *paint);
} else if (shader) {
blitter = allocator->createT<SkA8_Shader_Blitter>(device, *paint, shaderContext);
} else {
blitter = allocator->createT<SkA8_Blitter>(device, *paint);
}
break;
case kRGB_565_SkColorType:
blitter = SkBlitter_ChooseD565(device, *paint, shaderContext, allocator);
break;
case kN32_SkColorType:
if (shader) {
blitter = allocator->createT<SkARGB32_Shader_Blitter>(
device, *paint, shaderContext);
} else if (paint->getColor() == SK_ColorBLACK) {
blitter = allocator->createT<SkARGB32_Black_Blitter>(device, *paint);
} else if (paint->getAlpha() == 0xFF) {
blitter = allocator->createT<SkARGB32_Opaque_Blitter>(device, *paint);
} else {
blitter = allocator->createT<SkARGB32_Blitter>(device, *paint);
}
break;
default:
SkDEBUGFAIL("unsupported device config");
blitter = allocator->createT<SkNullBlitter>();
break;
}
if (shader3D) {
SkBlitter* innerBlitter = blitter;
// innerBlitter was allocated by allocator, which will delete it.
// We know shaderContext or its proxies is of type Sk3DShaderContext, so we need to
// wrapper the blitter to notify it when we see an emboss mask.
blitter = allocator->createT<Sk3DBlitter>(innerBlitter, shaderContext);
}
return blitter;
}
///////////////////////////////////////////////////////////////////////////////
class SkTransparentShaderContext : public SkShader::Context {
public:
SkTransparentShaderContext(const SkShader& shader, const SkShader::ContextRec& rec)
// Override rec with the identity matrix, so it is guaranteed to be invertible.
: INHERITED(shader, SkShader::ContextRec(*rec.fDevice, *rec.fPaint, SkMatrix::I())) {}
virtual void shadeSpan(int x, int y, SkPMColor colors[], int count) SK_OVERRIDE {
sk_bzero(colors, count * sizeof(SkPMColor));
}
private:
typedef SkShader::Context INHERITED;
};
SkShaderBlitter::SkShaderBlitter(const SkBitmap& device, const SkPaint& paint,
SkShader::Context* shaderContext)
: INHERITED(device)
, fShader(paint.getShader())
, fShaderContext(shaderContext) {
SkASSERT(fShader);
SkASSERT(fShaderContext);
fShader->ref();
fShaderFlags = fShaderContext->getFlags();
}
SkShaderBlitter::~SkShaderBlitter() {
fShader->unref();
}
bool SkShaderBlitter::resetShaderContext(const SkShader::ContextRec& rec) {
// Only destroy the old context if we have a new one. We need to ensure to have a
// live context in fShaderContext because the storage is owned by an SkSmallAllocator
// outside of this class.
// The new context will be of the same size as the old one because we use the same
// shader to create it. It is therefore safe to re-use the storage.
fShaderContext->~Context();
SkShader::Context* ctx = fShader->createContext(rec, (void*)fShaderContext);
if (NULL == ctx) {
// Need a valid context in fShaderContext's storage, so we can later (or our caller) call
// the in-place destructor.
SkNEW_PLACEMENT_ARGS(fShaderContext, SkTransparentShaderContext, (*fShader, rec));
return false;
}
return true;
}