C++ SkPixelRef类代码示例

bool SkBitmapProcShader::toDumpString(SkString* str) const {
    str->printf("BitmapShader: [%d %d %d",
                fRawBitmap.width(), fRawBitmap.height(),
                fRawBitmap.bytesPerPixel());

    // add the pixelref
    SkPixelRef* pr = fRawBitmap.pixelRef();
    if (pr) {
        const char* uri = pr->getURI();
        if (uri) {
            str->appendf(" \"%s\"", uri);
        }
    }

    // add the (optional) matrix
    {
        SkMatrix m;
        if (this->getLocalMatrix(&m)) {
            SkString info;
            m.toDumpString(&info);
            str->appendf(" %s", info.c_str());
        }
    }

    str->appendf(" [%s %s]]",
                 gTileModeName[fState.fTileModeX],
                 gTileModeName[fState.fTileModeY]);
    return true;
}

sk_sp<SkImage> SkImage::MakeFromBitmap(const SkBitmap& bm) {
    SkPixelRef* pr = bm.pixelRef();
    if (nullptr == pr) {
        return nullptr;
    }

#if SK_SUPPORT_GPU
    if (GrTexture* tex = pr->getTexture()) {
        SkAutoTUnref<GrTexture> unrefCopy;
        if (!bm.isImmutable()) {
            tex = GrDeepCopyTexture(tex, SkBudgeted::kNo);
            if (nullptr == tex) {
                return nullptr;
            }
            unrefCopy.reset(tex);
        }
        const SkImageInfo info = bm.info();
        return sk_make_sp<SkImage_Gpu>(info.width(), info.height(), bm.getGenerationID(),
                                       info.alphaType(), tex, sk_ref_sp(info.colorSpace()),
                                       SkBudgeted::kNo);
    }
#endif

    // This will check for immutable (share or copy)
    return SkMakeImageFromRasterBitmap(bm);
}

static SkData* encode_to_dct_data(size_t* pixelRefOffset, const SkBitmap& bitmap) {
    if (gJpegQuality == -1) {
        return NULL;
    }

    SkBitmap bm = bitmap;
#if defined(SK_BUILD_FOR_MAC)
    // Workaround bug #1043 where bitmaps with referenced pixels cause
    // CGImageDestinationFinalize to crash
    SkBitmap copy;
    bitmap.deepCopyTo(&copy, bitmap.config());
    bm = copy;
#endif

    SkPixelRef* pr = bm.pixelRef();
    if (pr != NULL) {
        SkData* data = pr->refEncodedData();
        if (data != NULL) {
            *pixelRefOffset = bm.pixelRefOffset();
            return data;
        }
    }

    *pixelRefOffset = 0;
    return SkImageEncoder::EncodeData(bm,
                                      SkImageEncoder::kJPEG_Type,
                                      gJpegQuality);
}

bool SkBitmapProcState::lockBaseBitmap() {
    SkPixelRef* pr = fOrigBitmap.pixelRef();

    if (pr->isLocked() || !pr->implementsDecodeInto()) {
        // fast-case, no need to look in our cache
        fScaledBitmap = fOrigBitmap;
        fScaledBitmap.lockPixels();
        if (NULL == fScaledBitmap.getPixels()) {
            return false;
        }
    } else {
        if (!SkBitmapCache::Find(fOrigBitmap, 1, 1, &fScaledBitmap)) {
            if (!get_locked_pixels(fOrigBitmap, 0, &fScaledBitmap)) {
                return false;
            }

            // TODO: if fScaled comes back at a different width/height than fOrig,
            // we need to update the matrix we are using to sample from this guy.

            SkBitmapCache::Add(fOrigBitmap, 1, 1, fScaledBitmap);
        }
    }
    fBitmap = &fScaledBitmap;
    return true;
}

SkImage* SkImage::NewFromBitmap(const SkBitmap& bm) {
    SkPixelRef* pr = bm.pixelRef();
    if (nullptr == pr) {
        return nullptr;
    }

#if SK_SUPPORT_GPU
    if (GrTexture* tex = pr->getTexture()) {
        SkAutoTUnref<GrTexture> unrefCopy;
        if (!bm.isImmutable()) {
            const bool notBudgeted = false;
            tex = GrDeepCopyTexture(tex, notBudgeted);
            if (nullptr == tex) {
                return nullptr;
            }
            unrefCopy.reset(tex);
        }
        const SkImageInfo info = bm.info();
        return new SkImage_Gpu(info.width(), info.height(), bm.getGenerationID(), info.alphaType(),
                               tex, 0, SkSurface::kNo_Budgeted);
    }
#endif

    // This will check for immutable (share or copy)
    return SkNewImageFromRasterBitmap(bm, nullptr);
}

bool SkBitmapProcState::lockBaseBitmap() {
    AutoScaledCacheUnlocker unlocker(&fScaledCacheID);

    SkPixelRef* pr = fOrigBitmap.pixelRef();

    SkASSERT(NULL == fScaledCacheID);

    if (pr->isLocked() || !pr->implementsDecodeInto()) {
        // fast-case, no need to look in our cache
        fScaledBitmap = fOrigBitmap;
        fScaledBitmap.lockPixels();
        if (NULL == fScaledBitmap.getPixels()) {
            return false;
        }
    } else {
        fScaledCacheID = SkScaledImageCache::FindAndLock(fOrigBitmap,
                                                         SK_Scalar1, SK_Scalar1,
                                                         &fScaledBitmap);
        if (fScaledCacheID) {
            fScaledBitmap.lockPixels();
            if (!fScaledBitmap.getPixels()) {
                fScaledBitmap.unlockPixels();
                // found a purged entry (discardablememory?), release it
                SkScaledImageCache::Unlock(fScaledCacheID);
                fScaledCacheID = NULL;
                // fall through to rebuild
            }
        }

        if (NULL == fScaledCacheID) {
            if (!get_locked_pixels(fOrigBitmap, 0, &fScaledBitmap)) {
                return false;
            }

            // TODO: if fScaled comes back at a different width/height than fOrig,
            // we need to update the matrix we are using to sample from this guy.

            fScaledCacheID = SkScaledImageCache::AddAndLock(fOrigBitmap,
                                                            SK_Scalar1, SK_Scalar1,
                                                            fScaledBitmap);
            if (!fScaledCacheID) {
                fScaledBitmap.reset();
                return false;
            }
        }
    }
    fBitmap = &fScaledBitmap;
    unlocker.release();
    return true;
}

static GrTexture* create_texture_from_yuv(GrContext* ctx, const SkBitmap& bm,
                                          const GrSurfaceDesc& desc) {
    // Subsets are not supported, the whole pixelRef is loaded when using YUV decoding
    SkPixelRef* pixelRef = bm.pixelRef();
    if ((nullptr == pixelRef) ||
        (pixelRef->info().width() != bm.info().width()) ||
        (pixelRef->info().height() != bm.info().height())) {
        return nullptr;
    }

    PixelRef_GrYUVProvider provider(pixelRef);

    return provider.refAsTexture(ctx, desc, !bm.isVolatile());
}

static bool get_locked_pixels(const SkBitmap& src, int pow2, SkBitmap* dst) {
    SkPixelRef* pr = src.pixelRef();
    if (pr && pr->decodeInto(pow2, dst)) {
        return true;
    }

    /*
     *  If decodeInto() fails, it is possibe that we have an old subclass that
     *  does not, or cannot, implement that. In that case we fall back to the
     *  older protocol of having the pixelRef handle the caching for us.
     */
    *dst = src;
    dst->lockPixels();
    return SkToBool(dst->getPixels());
}

void SkBinaryWriteBuffer::writeBitmap(const SkBitmap& bitmap) {
    // Record the width and height. This way if readBitmap fails a dummy bitmap can be drawn at the
    // right size.
    this->writeInt(bitmap.width());
    this->writeInt(bitmap.height());

    // Record information about the bitmap in one of two ways, in order of priority:
    // 1. If there is a function for encoding bitmaps, use it to write an encoded version of the
    //    bitmap. After writing a boolean value of false, signifying that a heap was not used, write
    //    the size of the encoded data. A non-zero size signifies that encoded data was written.
    // 2. Call SkBitmap::flatten. After writing a boolean value of false, signifying that a heap was
    //    not used, write a zero to signify that the data was not encoded.

    // Write a bool to indicate that we did not use an SkBitmapHeap. That feature is deprecated.
    this->writeBool(false);

    SkPixelRef* pixelRef = bitmap.pixelRef();
    if (pixelRef) {
        // see if the pixelref already has an encoded version
        SkAutoDataUnref existingData(pixelRef->refEncodedData());
        if (existingData.get() != nullptr) {
            // Assumes that if the client did not set a serializer, they are
            // happy to get the encoded data.
            if (!fPixelSerializer || fPixelSerializer->useEncodedData(existingData->data(),
                                                                      existingData->size())) {
                write_encoded_bitmap(this, existingData, bitmap.pixelRefOrigin());
                return;
            }
        }

        // see if the caller wants to manually encode
        SkAutoPixmapUnlock result;
        if (fPixelSerializer && bitmap.requestLock(&result)) {
            SkAutoDataUnref data(fPixelSerializer->encode(result.pixmap()));
            if (data.get() != nullptr) {
                // if we have to "encode" the bitmap, then we assume there is no
                // offset to share, since we are effectively creating a new pixelref
                write_encoded_bitmap(this, data, SkIPoint::Make(0, 0));
                return;
            }
        }
    }

    this->writeUInt(0); // signal raw pixels
    SkBitmap::WriteRawPixels(this, bitmap);
}

static void toString(const SkBitmap& bm, SkString* str) {
    str->printf("bitmap:[%d %d] %s", bm.width(), bm.height(),
                toString(bm.config()));

    SkPixelRef* pr = bm.pixelRef();
    if (NULL == pr) {
        // show null or the explicit pixel address (rare)
        str->appendf(" pixels:%p", bm.getPixels());
    } else {
        const char* uri = pr->getURI();
        if (uri) {
            str->appendf(" uri:\"%s\"", uri);
        } else {
            str->appendf(" pixelref:%p", pr);
        }
    }
}

static void Bitmap_reconfigure(JNIEnv* env, jobject clazz, jlong bitmapHandle,
        jint width, jint height, jint configHandle, jint allocSize,
        jboolean requestPremul) {
    SkBitmap* bitmap = reinterpret_cast<SkBitmap*>(bitmapHandle);
    SkColorType colorType = GraphicsJNI::legacyBitmapConfigToColorType(configHandle);

    // ARGB_4444 is a deprecated format, convert automatically to 8888
    if (colorType == kARGB_4444_SkColorType) {
        colorType = kN32_SkColorType;
    }

    if (width * height * SkColorTypeBytesPerPixel(colorType) > allocSize) {
        // done in native as there's no way to get BytesPerPixel in Java
        doThrowIAE(env, "Bitmap not large enough to support new configuration");
        return;
    }
    SkPixelRef* ref = bitmap->pixelRef();
    ref->ref();
    SkAlphaType alphaType;
    if (bitmap->colorType() != kRGB_565_SkColorType
            && bitmap->alphaType() == kOpaque_SkAlphaType) {
        // If the original bitmap was set to opaque, keep that setting, unless it
        // was 565, which is required to be opaque.
        alphaType = kOpaque_SkAlphaType;
    } else {
        // Otherwise respect the premultiplied request.
        alphaType = requestPremul ? kPremul_SkAlphaType : kUnpremul_SkAlphaType;
    }
    bitmap->setInfo(SkImageInfo::Make(width, height, colorType, alphaType));
    // FIXME: Skia thinks of an SkPixelRef as having a constant SkImageInfo (except for
    // its alphatype), so it would make more sense from Skia's perspective to create a
    // new SkPixelRef. That said, libhwui uses the pointer to the SkPixelRef as a key
    // for its cache, so it won't realize this is the same Java Bitmap.
    SkImageInfo& info = const_cast<SkImageInfo&>(ref->info());
    // Use the updated from the SkBitmap, which may have corrected an invalid alphatype.
    // (e.g. 565 non-opaque)
    info = bitmap->info();
    bitmap->setPixelRef(ref);

    // notifyPixelsChanged will increment the generation ID even though the actual pixel data
    // hasn't been touched. This signals the renderer that the bitmap (including width, height,
    // colortype and alphatype) has changed.
    ref->notifyPixelsChanged();
    ref->unref();
}

static void jni_eglCreatePixmapSurface(JNIEnv *_env, jobject _this, jobject out_sur,
        jobject display, jobject config, jobject native_pixmap,
        jintArray attrib_list)
{
    if (display == NULL || config == NULL || native_pixmap == NULL
        || !validAttribList(_env, attrib_list)) {
        jniThrowException(_env, "java/lang/IllegalArgumentException", NULL);
        return;
    }
    EGLDisplay dpy = getDisplay(_env, display);
    EGLConfig  cnf = getConfig(_env, config);
    jint* base = 0;

    SkBitmap const * nativeBitmap =
            (SkBitmap const *)_env->GetIntField(native_pixmap,
                    gBitmap_NativeBitmapFieldID);
    SkPixelRef* ref = nativeBitmap ? nativeBitmap->pixelRef() : 0;
    if (ref == NULL) {
        jniThrowException(_env, "java/lang/IllegalArgumentException", "Bitmap has no PixelRef");
        return;
    }

    SkSafeRef(ref);
    ref->lockPixels();

    egl_native_pixmap_t pixmap;
    pixmap.version = sizeof(pixmap);
    pixmap.width  = nativeBitmap->width();
    pixmap.height = nativeBitmap->height();
    pixmap.stride = nativeBitmap->rowBytes() / nativeBitmap->bytesPerPixel();
    pixmap.format = convertPixelFormat(nativeBitmap->config());
    pixmap.data   = (uint8_t*)ref->pixels();

    base = beginNativeAttribList(_env, attrib_list);
    EGLSurface sur = eglCreatePixmapSurface(dpy, cnf, &pixmap, base);
    endNativeAttributeList(_env, attrib_list, base);

    if (sur != EGL_NO_SURFACE) {
        _env->SetIntField(out_sur, gSurface_EGLSurfaceFieldID, (int)sur);
        _env->SetIntField(out_sur, gSurface_NativePixelRefFieldID, (int)ref);
    } else {
        ref->unlockPixels();
        SkSafeUnref(ref);
    }
}

sk_sp<SkPixelRef> SkMallocPixelRef::MakeWithData(const SkImageInfo& info,
                                                size_t rowBytes,
                                                sk_sp<SkColorTable> ctable,
                                                sk_sp<SkData> data) {
    SkASSERT(data != nullptr);
    if (!is_valid(info, ctable.get())) {
        return nullptr;
    }
    if ((rowBytes < info.minRowBytes()) || (data->size() < info.getSafeSize(rowBytes))) {
        return nullptr;
    }
    // must get this address before we call release
    void* pixels = const_cast<void*>(data->data());
    SkPixelRef* pr = new SkMallocPixelRef(info, pixels, rowBytes, std::move(ctable),
                                          sk_data_releaseproc, data.release());
    pr->setImmutable(); // since we were created with (immutable) data
    return sk_sp<SkPixelRef>(pr);
}

static jboolean jni_eglDestroySurface(JNIEnv *_env, jobject _this, jobject display, jobject surface) {
    if (display == NULL || surface == NULL) {
        jniThrowException(_env, "java/lang/IllegalArgumentException", NULL);
        return JNI_FALSE;
    }
    EGLDisplay dpy = getDisplay(_env, display);
    EGLSurface sur = getSurface(_env, surface);

    if (sur) {
        SkPixelRef* ref = (SkPixelRef*)(_env->GetIntField(surface,
                gSurface_NativePixelRefFieldID));
        if (ref) {
            ref->unlockPixels();
            SkSafeUnref(ref);
        }
    }
    return eglDestroySurface(dpy, sur);
}

static void Bitmap_reconfigure(JNIEnv* env, jobject clazz, jlong bitmapHandle,
        jint width, jint height, jint configHandle, jint allocSize) {
    SkBitmap* bitmap = reinterpret_cast<SkBitmap*>(bitmapHandle);
    SkBitmap::Config config = static_cast<SkBitmap::Config>(configHandle);    
    if (width * height * SkBitmap::ComputeBytesPerPixel(config) > allocSize) {
        // done in native as there's no way to get BytesPerPixel in Java
        doThrowIAE(env, "Bitmap not large enough to support new configuration");
        return;
    }
    SkPixelRef* ref = bitmap->pixelRef();
    SkSafeRef(ref);
    bitmap->setConfig(config, width, height);
    bitmap->setPixelRef(ref);

    // notifyPixelsChanged will increment the generation ID even though the actual pixel data
    // hasn't been touched. This signals the renderer that the bitmap (including width, height,
    // and config) has changed.
    ref->notifyPixelsChanged();
    SkSafeUnref(ref);
}