Files
MapLibreParticleLab/include/mbgl/util/image.hpp
2016-11-01 18:41:52 +01:00

68 lines
1.7 KiB
C++

#pragma once
#include <mbgl/util/noncopyable.hpp>
#include <mbgl/util/size.hpp>
#include <string>
#include <memory>
#include <algorithm>
namespace mbgl {
enum class ImageAlphaMode {
Unassociated,
Premultiplied,
Exclusive, // Alpha-channel only
};
template <ImageAlphaMode Mode>
class Image : private util::noncopyable {
public:
Image() = default;
Image(Size size_)
: size(std::move(size_)),
data(std::make_unique<uint8_t[]>(bytes())) {}
Image(Size size_, std::unique_ptr<uint8_t[]> data_)
: size(std::move(size_)),
data(std::move(data_)) {}
Image(Image&& o)
: size(o.size),
data(std::move(o.data)) {}
Image& operator=(Image&& o) {
size = o.size;
data = std::move(o.data);
return *this;
}
bool operator==(const Image& rhs) const {
return size == rhs.size &&
std::equal(data.get(), data.get() + bytes(), rhs.data.get(),
rhs.data.get() + rhs.bytes());
}
bool valid() const {
return size && data.get() != nullptr;
}
size_t stride() const { return channels * size.width; }
size_t bytes() const { return stride() * size.height; }
Size size;
static constexpr size_t channels = Mode == ImageAlphaMode::Exclusive ? 1 : 4;
std::unique_ptr<uint8_t[]> data;
};
using UnassociatedImage = Image<ImageAlphaMode::Unassociated>;
using PremultipliedImage = Image<ImageAlphaMode::Premultiplied>;
using AlphaImage = Image<ImageAlphaMode::Exclusive>;
// TODO: don't use std::string for binary data.
PremultipliedImage decodeImage(const std::string&);
std::string encodePNG(const PremultipliedImage&);
} // namespace mbgl