[rmodels] `LoadModel()` Model exported from Blender with Draco compression enabled results in a crash

[charlie-sans]

Please, before submitting a new issue verify and check:

• I tested it on latest raylib version from master branch
• I checked there is no similar issue already reported
• I checked the documentation on the wiki
• My code has no errors or misuse of raylib

Issue description

when loading a GLB model file that has been exported from blender with Draco Compression enabled in the
export settings, Raylib segfaults during the loading of mesh data.

The GLTF spec says extensionsRequired must be honored, but raylib currently doesn’t support KHR_draco_mesh_compression.

Environment

Windows 11 64 bit & linux 64 bit (arch distro)

Issue Screenshot

here's what my program under gdb looks like.

Code Example

#include <raylib.h>

int main(void)
{
    // Initialize window and OpenGL context
    InitWindow(800, 450, "raylib GLB Draco crash test");

    // Try to load Draco‑compressed model
    Model model = LoadModel("world_draco_compressed.glb");

    // If model.meshCount < 0 something went wrong, but mostly should segfault when loading the model at all.
    TraceLog(LOG_INFO, "Loaded model meshCount: %d", model.meshCount);

    // Main loop just stays open so loader runs
    while (!WindowShouldClose())
    {
        BeginDrawing();
            ClearBackground(RAYWHITE);
        EndDrawing();
    }

    UnloadModel(model);
    CloseWindow();

    return 0;
}

[charlie-sans]

it seems that it doesn't even alert you about unsupported khr extensions present in the glb/gltf model too.

[raysan5]

@charlie-sans I'm afraid Draco compression is not supported by raylib, does cgltf library support decompressing that data?