Method encode

webgl/transcoder/basis_wrappers.cpp:1530–1651

    }

    uint32_t encode(const emscripten::val& dst_basis_file_js_val)
    {
        if (!g_basis_initialized_flag)
        {
#if BASISU_DEBUG_PRINTF
            printf("basis_encoder::encode: Must call basis_init() first!\n");
#endif
            assert(0);
            return 0;
        }

        // We don't use threading for now, but the compressor needs a job pool.
        uint32_t num_new_threads = 0;
        bool enable_threading = false;
        
#if WASM_THREADS_ENABLED
        if ((emscripten_has_threading_support()) && (m_threading_enabled) && (m_num_extra_worker_threads))
        {
            enable_threading = true;
            num_new_threads = m_num_extra_worker_threads;
        }
#endif

        // We always need a job pool, but making a job pool with just 1 thread doesn't actually create any additional helper threads (i.e. it always utilizes the main thread).
        job_pool jpool(1 + num_new_threads);

        // Initialize the compression parameters structure. This is the same structure that the command line tool fills in.
        basis_compressor_params &params = m_params;
        
        // Check to see if we would risk running out of memory in 32-bit WASM. There's not much we can do about this limit until memory64 is available.
        uint64_t total_src_texels = 0;
        
        for (uint32_t i = 0; i < m_params.m_source_images.size(); i++)
            total_src_texels += m_params.m_source_images[i].get_total_pixels();

        for (uint32_t i = 0; i < m_params.m_source_images_hdr.size(); i++)
            total_src_texels += m_params.m_source_images_hdr[i].get_total_pixels();
                
        // Try to prevent running out of memory inside WASM.
        uint32_t max_pixels_thresh = BASISU_ENCODER_MAX_SOURCE_IMAGE_PIXELS;

        // The simpler compressors need less temporary memory, so their threshold can be higher.
        if (m_params.is_etc1s() || m_params.is_uastc_ldr_4x4() || m_params.is_uastc_hdr_4x4())
        {
            max_pixels_thresh = BASISU_ENCODER_MAX_SOURCE_IMAGE_PIXELS_HIGHER_LIMIT;
        }
                
        if (total_src_texels > max_pixels_thresh)
        {
            printf("ERROR: basis_encoder::encode(): The total number of source texels to compress %llu is greater than %u, which is likely too large for WASM (above BASISU_ENCODER_MAX_SOURCE_IMAGE_PIXELS in basis_wrappers.cpp).", 
                total_src_texels, max_pixels_thresh);
            return 0;
        }

        params.m_pJob_pool = &jpool;

        params.m_multithreading = enable_threading;