This function imports a design tree via a stream.
The design tree will be added to the given existing model.
The return value contains the first instance not referenced by any other instance or zero if it does not exist. In case the imported model is created with SaveInstanceTree() this instance is unique and equal to the instance used within the call SaveInstanceTree().


//   Strong typing definition
OwlInstance     ImportModelS(
                        OwlModel                model,
                        const void              * callback

//   Weak typing definition
int64_t __declspec(dllexport) __stdcall ImportModelS(
                                                int64_t                 model,
                                                const void              * callback

Property model

Size: 64 bit / 8 byte (value)
The handle to the model. The model handle is static during its existance. Several models can be opened simultaniously within one session. Different models are always independent, threads are allowed to be running on different models simultaniously.

Property callback

Size: 64 bit / 8 byte (reference)
The pointer to the function that will be called within this function. Please look at the examples how to create the callback function and how it will be called. In case this is not possible or complex there is an array call, technically the same call, however the callback function is embedded within the library.

Example (based on pure API calls)

Here you can find code snippits that show how the API call ImportModelS can be used.

#include    "./include/engine.h"
#include    <assert.h>

const int_t BLOCK_LENGTH_READ = 65535;  //  MAX: 65535
FILE        * myFileRead = nullptr;

int_t   __stdcall   ReadCallBackFunction(unsigned char * content)
    if (myFileRead == nullptr || feof(myFileRead)) {
        return  -1;

    int_t   size = fread(content, 1, BLOCK_LENGTH_READ, myFileRead);

    return  size;

void    ImportModelByStream(int64_t model, wchar_t * fileName)
    assert(myFileRead == nullptr);

    _wfopen_s(&myFileRead, fileName, L"rb");
    if (model && &myFileRead) {
        ImportModelS(model, &ReadCallBackFunction);

    else {