write_deep_tiled

CMakeLists.txt

cmake_minimum_required(VERSION 3.5)
project(write_deep_tiled)

find_package(Imath 3.0.1)
find_package(OpenEXR 3.0.1)

add_executable(write_deep_tiled main.cpp)
target_link_libraries(write_deep_tiled OpenEXR::OpenEXR Imath::Imath)

main.cpp

#include <Imath/ImathBox.h>
#include <OpenEXR/ImfChannelList.h>
#include <OpenEXR/ImfDeepFrameBuffer.h>
#include <OpenEXR/ImfDeepTiledOutputFile.h>
#include <OpenEXR/ImfHeader.h>

#include <cstdint>
#include <vector>

using Imath::Box2i;
using Imath::half;
using Imath::V2i;

int main() {
    int width = 256;
    int height = 256;
    int num_pixels = width * height;

    Box2i display_window(V2i(0, 0), V2i(width - 1, height - 1));
    Box2i data_window = display_window;

    Imf::Header header(display_window, data_window);

    header.setTileDescription(Imf::TileDescription(64, 64, Imf::ONE_LEVEL));
    header.compression() = Imf::NO_COMPRESSION;

    header.channels().insert("Z", Imf::Channel(Imf::FLOAT));
    header.channels().insert("A", Imf::Channel(Imf::HALF));

    Imf::DeepTiledOutputFile file("wdtof_cpp.exr", header);

    std::vector<float*> z_data;
    std::vector<half*> a_data;
    for (int y = 0; y < height; ++y) {
        float v = float(y) / float(height) * 8.0f;
        for (int x = 0; x < width; ++x) {
            float u = float(x) / float(width) * 8.0f;

            z_data.push_back(new float((sin(u) * sin(v)) + 1));
            a_data.push_back(new half(1.0f));
        }
    }

    std::vector<uint32_t> sample_counts;
    sample_counts.reserve(num_pixels);
    for (int i = 0; i < num_pixels; ++i) {
        sample_counts.push_back(1);
    }

    Imf::DeepFrameBuffer frame_buffer;
    frame_buffer.insertSampleCountSlice(
        Imf::Slice(Imf::UINT, (char*)sample_counts.data(), sizeof(uint32_t),
                   sizeof(uint32_t) * width));

    frame_buffer.insert(
        "Z", Imf::DeepSlice(Imf::FLOAT, (char*)z_data.data(), sizeof(float*),
                            sizeof(float*) * width, sizeof(float)));

    frame_buffer.insert(
        "A", Imf::DeepSlice(Imf::HALF, (char*)a_data.data(), sizeof(half*),
                            sizeof(half*) * width, sizeof(half)));

    file.setFrameBuffer(frame_buffer);

    file.writeTiles(0, file.numXTiles() - 1, 0, file.numYTiles() - 1);
}