LinearImage.cpp

/*
 * Copyright (C) 2018 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 <image/LinearImage.h>

#include <utils/Panic.h>

#include <cstring> // for memset
#include <memory>

#include <new>
#include <limits>

namespace image  {

struct LinearImage::SharedReference {
    SharedReference(uint32_t width, uint32_t height, uint32_t channels) {
        const uint64_t nfloats64 = (uint64_t)width * (uint64_t)height * (uint64_t)channels;
        FILAMENT_CHECK_PRECONDITION(nfloats64 <= UINT32_MAX && nfloats64 <= (std::numeric_limits<size_t>::max() / sizeof(float)))
                << "LinearImage allocation size is too large";
        const uint32_t nfloats = (uint32_t)nfloats64;
        float* floats = new float[nfloats];
        memset(floats, 0, sizeof(float) * nfloats);
        pixels = std::shared_ptr<float>(floats, std::default_delete<float[]>());
    }
    std::shared_ptr<float> pixels;
};

LinearImage::~LinearImage() {
    delete mDataRef;
}

LinearImage::LinearImage(uint32_t width, uint32_t height, uint32_t channels) :
    mDataRef(new SharedReference(width, height, channels)),
    mData(mDataRef->pixels.get()),
    mWidth(width), mHeight(height), mChannels(channels) {}

LinearImage::LinearImage(const LinearImage& that) {
    *this = that;
}

LinearImage& LinearImage::operator=(const LinearImage& that) {
    auto newDataRef = that.mDataRef
        ? new SharedReference(*that.mDataRef)
        : nullptr;
    delete mDataRef;
    mDataRef = newDataRef;
    
    mData = that.mData;
    mWidth = that.mWidth;
    mHeight = that.mHeight;
    mChannels = that.mChannels;
    return *this;
}

}  // namespace image