core/jni/android/graphics/NinePatchPeeker.cpp

/*
 * Copyright (C) 2011 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.
 */

#include "NinePatchPeeker.h"

#include "SkBitmap.h"

using namespace android;

bool NinePatchPeeker::peek(const char tag[], const void* data, size_t length) {
    if (strcmp("npTc", tag) == 0 && length >= sizeof(Res_png_9patch)) {
        Res_png_9patch* patch = (Res_png_9patch*) data;
        size_t patchSize = patch->serializedSize();
        assert(length == patchSize);
        // You have to copy the data because it is owned by the png reader
        Res_png_9patch* patchNew = (Res_png_9patch*) malloc(patchSize);
        memcpy(patchNew, patch, patchSize);
        // this relies on deserialization being done in place
        Res_png_9patch::deserialize(patchNew);
        patchNew->fileToDevice();
        if (fPatchIsValid) {
            free(fPatch);
        }
        fPatch = patchNew;
        //printf("9patch: (%d,%d)-(%d,%d)\n",
        //       fPatch.sizeLeft, fPatch.sizeTop,
        //       fPatch.sizeRight, fPatch.sizeBottom);
        fPatchIsValid = true;

        // now update our host to force index or 32bit config
        // 'cause we don't want 565 predithered, since as a 9patch, we know
        // we will be stretched, and therefore we want to dither afterwards.
        static const SkBitmap::Config gNo565Pref[] = {
            SkBitmap::kIndex8_Config,
            SkBitmap::kIndex8_Config,
            SkBitmap::kARGB_8888_Config,
            SkBitmap::kARGB_8888_Config,
            SkBitmap::kARGB_8888_Config,
            SkBitmap::kARGB_8888_Config,
        };
        fHost->setPrefConfigTable(gNo565Pref);
    } else {
        fPatch = NULL;
    }
    return true;    // keep on decoding
}