As told in this post
https://devtalk.nvidia.com/default/topic/1030316/optix/valid-material-/post/5244544/#5244544
i ask my issue again here in the MDL SDK forum:
I analyzed the MDL Expressions sample and I found some simpler MDL examples in the MDL SDK 296300.4444
Although I completely built the MDL Expressions sample from original OptiX SDK 5.0.0 installation it crashes with some of the MDL examples of the MDL SDK. First they load properly all the texture files and they prompt on error correctly if there’s a file missing. But on all cases where “df::fresnel_layer” is used and on many cases where “df::weighted_layer” is used, a crash occurs (but no error message). The ones I got working are: chrome.mdl, colored_wax.mdl, copper.mdl, aluminium_anodized.mdl and colored_flint_glass.mdl;
the copper.mdl sample technically works when replacing “fresnel_bsdf” with pure “diffuse_reflection_bsdf” or “simple_glossy_bsdf” all other samples in the MDL SDK crash on my system with the exception shown in the attachment. I always use “surface.scattering.tint” as expression path.
to reproduce this exception: in file “optixMDLExpressions.mdl” you simply can replace the material “M_checker” with this version:
export material M_checker() = let{
bsdf fresnel_bsdf = df::fresnel_layer(
ior: color(1.5, 1.5, 1.5),
weight: 0.5,
layer: df::simple_glossy_bsdf(tint: checker(50), roughness_u : 0.5),
base: df::diffuse_reflection_bsdf(tint: checker(100))
);
} in
material(
surface: material_surface(
// scattering: df::diffuse_reflection_bsdf(tint: checker(100)) // OK (=ORG)
// scattering: df::simple_glossy_bsdf(tint: checker(50), roughness_u : 0.5) // OK
scattering: fresnel_bsdf // CRASH
)
);
System: OptiX 5.0.0 SDK CUDA 9.0 GTX 1050 Win10PRO 64bit (version 1607) device driver: 388.59 TDR re-enabled:with longer delays VS2017 v 15.5.6 (toolkit v140 of VS2015); mdl_wrapper.dll version: MDL SDK 2017.1, build 296300.2288, 27 Sep 2017, nt-x86-64-vc11
original post here: https://devtalk.nvidia.com/default/topic/1030316/optix/valid-material-/post/5244228/#5244228