to_image_array() [1/2]

std::shared_ptr< Core::VKImage > MayaFlux::Kakshya::TextureContainer::to_image_array

(

)

const

Upload all layers as a Vulkan 2D array texture.

Concatenates pixel data from all layers in order (layer 0 first) and calls TextureLoom::create_2d_array. The returned VKImage has array_layers == get_layer_count() and an image view of type VK_IMAGE_VIEW_TYPE_2D_ARRAY, making it bindable as sampler2DArray in GLSL.

All layers must have been populated before calling this. Empty layers contribute zero bytes and will produce incorrect GPU data.

Returns

Initialised VKImage with array_layers > 1, or nullptr on failure.

Definition at line 436 of file TextureContainer.cpp.

{
    const auto n = static_cast<uint32_t>(m_data.size());
    if (n == 0)
        return nullptr;
 
    if (n == 1) {
        std::shared_ptr<Core::VKImage> img;
        seqlock_read_void(m_slot_locks[0], 8, [&] {
            auto [ptr, bytes] = variant_bytes(m_data[0]);
            if (!ptr || bytes == 0)
                return;
            img = TextureLoom::instance().create_2d(m_width, m_height, m_format, ptr);
        });
        return img;
    }
 
    const size_t layer_bytes = byte_size();
    std::vector<uint8_t> combined(layer_bytes * n);
    for (uint32_t i = 0; i < n; ++i) {
        bool ok = seqlock_read_void(m_slot_locks[i], 8, [&] {
            auto [ptr, bytes] = variant_bytes(m_data[i]);
            if (!ptr || bytes != layer_bytes) {
                MF_ERROR(Journal::Component::Kakshya, Journal::Context::ContainerProcessing,
                    "TextureContainer::to_image_array layer {} has unexpected byte count ({} vs {})",
                    i, bytes, layer_bytes);
                return;
            }
            std::memcpy(combined.data() + i * layer_bytes, ptr, layer_bytes);
        });
        if (!ok)
            return nullptr;
    }
 
    return TextureLoom::instance().create_2d_array(m_width, m_height, n, m_format, combined.data());
}

References MF_ERROR, and ptr.