grr and rust-gpu pbr rendering

cat /etc/os-release
NAME="Pop!_OS"
VERSION="20.10"
ID=pop
ID_LIKE="ubuntu debian"
PRETTY_NAME="Pop!_OS 20.10"
VERSION_ID="20.10"
HOME_URL="https://pop.system76.com"
SUPPORT_URL="https://support.system76.com"
BUG_REPORT_URL="https://github.com/pop-os/pop/issues"
PRIVACY_POLICY_URL="https://system76.com/privacy"
VERSION_CODENAME=groovy
UBUNTU_CODENAME=groovy
LOGO=distributor-logo-pop-os

$ lspci|grep VGA
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Tonga PRO [Radeon R9 285/380] (rev f1)

$ lsgpu
sys:/sys/devices/pci0000:00/0000:00:02.0/0000:01:00.0/drm/card0
    subsystem       : drm
    drm card        : /dev/dri/card0
    parent          : sys:/sys/devices/pci0000:00/0000:00:02.0/0000:01:00.0

sys:/sys/devices/pci0000:00/0000:00:02.0/0000:01:00.0/drm/renderD128
    subsystem       : drm
    drm render      : /dev/dri/renderD128
    parent          : sys:/sys/devices/pci0000:00/0000:00:02.0/0000:01:00.0

sys:/sys/devices/pci0000:00/0000:00:02.0/0000:01:00.0
    subsystem       : pci
    drm card        : /dev/dri/card0
    drm render      : /dev/dri/renderD128
    vendor          : 1002
    device          : 6939

I downloaded all the required assets as requested. Why aren't they simply in the github project alongside the sources so that everybody may simply git clone the project without having to download the assets?

I then proceeded to "cargo build --release". Then ran "strace ./target/release/grr-gltf"

Here are the results of that:

write(1, "path:<<\"assets/lut_ggx.png\">>\n", 30path:<<"assets/lut_ggx.png">>
) = 30
openat(AT_FDCWD, "assets/lut_ggx.png", O_RDONLY|O_CLOEXEC) = 11
brk(0x555c128bf000)                     = 0x555c128bf000
read(11, "\211PNG\r\n\32\n\0\0\0\rIHDR\0\0\4\0\0\0\4\0\10\2\0\0\0\360\177\274"..., 32768) = 32768
brk(0x555c12bc7000)                     = 0x555c12bc7000
read(11, "Z L\215D\215\326\303B\fK\327\5k\260#\245l|\5\23\222^\302\261\2115\326(\311B\230"..., 32768) = 32768
brk(0x555c12bf7000)                     = 0x555c12bf7000
read(11, "<\305\210\26RH\266\343\tL\362ta)\224px\26E\345\177\00625b\v(\6\22\5\377\343"..., 32768) = 32768
read(11, "\200\251\374?\260\23\5`\347\376\377Oz\343\33\303\247\377\251\321\323`\300c\10\330\306\377T\352'0"..., 32768) = 32768
read(11, "\221|\207\350\177\322\313W\274ZpJ\376'\253 '\317.\22kP\354\226\220\347`d_b\230@"..., 32768) = 32768
read(11, "20\f\303;\4\310\216A\254Y\202\272\24610\f\311k\206\251\36\10\230AM\7+\340\226\322\323"..., 32768) = 28654
close(11)                               = 0
brk(0x555c12fc7000)                     = 0x555c12fc7000
write(1, "24.17462ms\n", 1124.17462ms
)            = 11
ioctl(10, DRM_IOCTL_AMDGPU_GEM_CREATE or DRM_IOCTL_VIA_ALLOCMEM, 0x7fff7b147110) = 0
ioctl(10, _IOC(_IOC_READ|_IOC_WRITE, 0x64, 0x48, 0x28), 0x7fff7b147120) = 0
ioctl(10, DRM_IOCTL_AMDGPU_CTX or DRM_IOCTL_ETNAVIV_GEM_NEW or DRM_IOCTL_LIMA_GEM_INFO or DRM_IOCTL_MSM_GEM_NEW or DRM_IOCTL_V3D_CREATE_BO or DRM_IOCTL_VC4_WAIT_BO, 0x7fff7b1470d0) = 0
futex(0x555c124ebd6c, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x555c124ebd18, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x555c125091dc, FUTEX_WAIT_BITSET, 2, NULL, FUTEX_BITSET_MATCH_ANY) = 0
futex(0x555c125b7a74, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x555c125b7a20, FUTEX_WAKE_PRIVATE, 1) = 1
ioctl(10, DRM_IOCTL_AMDGPU_GEM_CREATE or DRM_IOCTL_VIA_ALLOCMEM, 0x7fff7b146fc0) = 0
ioctl(10, _IOC(_IOC_READ|_IOC_WRITE, 0x64, 0x48, 0x28), 0x7fff7b146fd0) = 0
ioctl(10, DRM_IOCTL_AMDGPU_GEM_MMAP, 0x7fff7b147f50) = 0
mmap(NULL, 4194304, PROT_READ|PROT_WRITE, MAP_SHARED, 10, 0x127167000) = 0x7f3fe013f000
--- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x20} ---
rt_sigaction(SIGSEGV, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f401a0bcbb0}, NULL, 8) = 0
rt_sigreturn({mask=[]})                 = 93853942532464
--- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x20} ---
+++ killed by SIGSEGV (core dumped) +++
Segmentation fault (core dumped)