release: install.sh asks what to install, caches the NVIDIA DLLs and the engine models, and [Engine] defaults to auto

Verified copies go to ~/.cache/d4r: the next game's install copies them instead of downloading or building
again. Enabled = auto (the new default) turns the engine on when d4r/engine holds a model; the shim probes the
nine model folders. build-engine-models.sh gains --exact (NVIDIA's roundings) and --find-proton.

packaging/D4R_README.txt

@@ -57,13 +57,14 @@ that archive's d4r/README.txt: setup runs automatically when the ASI loads.
 @installer    d4r/ngx/_nvngx.dll. No sudo is needed. The driver archive is about 915 MiB; it is extracted,
 @installer    never executed. Downloads are temporary. Run it again to check the files; differing existing
 @installer    DLLs are backed up before replacement.
-@installer    It then builds the native engine's models in d4r/engine from those DLLs ([Engine] under
-@installer    Settings): Ray Reconstruction D, E and F straight from nvngx_dlssd.dll, and Super Resolution
-@installer    K, M and L (with their LDR variants) by rendering one test frame per model through d4r under
-@installer    GE-Proton 11, found in Steam's compatibility tools (or set D4R_PROTON=/path/to/GE-Proton11-3).
-@installer    The first time this takes a few minutes while DLSS's kernels compile. --no-engine skips it;
-@installer    bash install.sh --engine-only builds the models later, --rebuild-engine builds them again.
-@clean 2. Copy nvngx_dlss.dll into the d4r folder, and _nvngx.dll into d4r/ngx.
+@installer    Verified copies are kept in ~/.cache/d4r/nvidia, so installing d4r in the next game needs no
+@installer    download. install.sh then asks whether to set up d4r's own DLSS engine (recommended: faster,
+@installer    lower latency). That builds the engine's models in d4r/engine from the DLLs: Ray Reconstruction
+@installer    D, E and F straight from nvngx_dlssd.dll, and Super Resolution K, M and L (with their LDR
+@installer    variants) by rendering one test frame per model through d4r under GE-Proton 11, found in Steam's
+@installer    compatibility tools (or set D4R_PROTON=/path/to/GE-Proton11-3). It takes a minute or two once;
+@installer    the models are kept in ~/.cache/d4r/engine-models for the next game. bash install.sh --help lists
+@installer    options for scripted installs.
 @installer 3. In Steam, open the game's Properties:
 @clean 3. In Steam, open the game's Properties:
 @full 2. In Steam, open the game's Properties:
@@ -107,9 +108,10 @@ Settings
   PreferAccuracy = true. This uses original translated enc1/enc2 layers while retaining other
   native acceleration. It reduced trails in a captured Townfall sequence on RX 7700 XT and costs
   some GPU time. Restart after changing it; other scenes and RDNA4 hardware still need testing.
-- [Engine] Enabled = true (experimental, off by default) runs DLSS 4 (K), 4.5 (M and L) and Ray
-  Reconstruction (D, E and F) on d4r's own Vulkan inference engine: the work is recorded into the game's
-  own frame instead of going through CUDA emulation. It needs Mesa RADV with VK_KHR_cooperative_matrix
+- [Engine] runs DLSS 4 (K), 4.5 (M and L) and Ray Reconstruction (D, E and F) on d4r's own Vulkan
+  inference engine: the work is recorded into the game's own frame instead of going through CUDA
+  emulation, which is faster. Enabled = auto (the default) uses it whenever its models are in d4r/engine;
+  true / false force it on / off. It needs Mesa RADV with VK_KHR_cooperative_matrix
   and the models in d4r/engine: k (K), k-ldr (K in games without HDR), m and m-ldr (M), l and l-ldr (L),
   rr-d, rr-e and rr-f (Ray Reconstruction). Games and settings it does not cover (other models,
   display-resolution motion vectors with L or M) keep using the normal path,
@@ -197,7 +199,7 @@ Uninstall
 ---------
 Delete dxgi.dll, OptiScaler.ini, OptiScaler.log (if present), d3d12.dll, d3d12core.dll,
 D4R_README.txt, install.sh (if present) and the d4r folder from the game folder, and clear the launch options. The kernel
-cache in ~/.cache/d4r can be deleted too.
+cache in ~/.cache/d4r can be deleted too; it also holds install.sh's copies of the NVIDIA DLLs and the engine models.
 
 
 Licenses

packaging/build_engine_models.sh

@@ -2,7 +2,8 @@
 # Builds the native engine's models ([Engine] in d4r.ini) on this machine, from the NVIDIA DLLs install.sh put in
 # the d4r folder. Shipped as d4r/tools/build-engine-models.sh; install.sh runs it.
 #
-# usage: bash d4r/tools/build-engine-models.sh [--rr-only | --sr-only] [D4R_FOLDER]
+# usage: bash d4r/tools/build-engine-models.sh [--rr-only | --sr-only] [--exact] [D4R_FOLDER]
+#        bash d4r/tools/build-engine-models.sh --find-proton      prints the GE-Proton it would use (or nothing)
 #
 #   Ray Reconstruction  engine/rr-d, rr-e, rr-f   from d4r/nvngx_dlssd.dll 310.9.1 alone (about half a minute)
 #   Super Resolution    engine/k, k-ldr, m, m-ldr, l, l-ldr
@@ -11,19 +12,41 @@
 #                       GE-Proton, and the uploads are saved (a minute or two each; the first run also compiles
 #                       DLSS's kernels and creates a temporary Proton prefix)
 # Needs python3 with numpy, and for Super Resolution a GE-Proton (D4R_PROTON=/path/to/GE-Proton11-3 to choose one).
+# The models are the fastest builds (this GPU's own arithmetic; engine/README.md). --exact builds NVIDIA's roundings
+# instead: bit-identical to the CUDA path, about 20% slower (K is the same either way).
 # Everything written is derived from NVIDIA's DLLs: it stays in this folder and must not be redistributed.
 set -euo pipefail
 
 fail() { printf 'build-engine-models: %s\n' "$*" >&2; exit 1; }
-DO_RR=1 DO_SR=1
+DO_RR=1 DO_SR=1 FIND_PROTON=0
 while [[ $# -gt 0 ]]; do
   case "$1" in
     --rr-only) DO_SR=0; shift ;;
     --sr-only) DO_RR=0; shift ;;
-    -h|--help) sed -n '2,15p' "${BASH_SOURCE[0]}" | sed 's/^# \{0,1\}//'; exit 0 ;;
+    --exact) export D4R_RR_RELAXED=0 M_EXACT=1; shift ;;
+    --find-proton) FIND_PROTON=1; shift ;;
+    -h|--help) sed -n '2,19p' "${BASH_SOURCE[0]}" | sed 's/^# \{0,1\}//'; exit 0 ;;
     *) break ;;
   esac
 done
+find_proton() {
+  # a GE-Proton: D4R_PROTON, else GE-Proton11-3 (the tested one), else the newest stock GE-Proton11-N in Steam's
+  # compatibility tools. Renamed or rebuilt variants (2026-10-14: one with a suffix after the version number) can
+  # fail NGX's CUDA initialisation, so they are only used when named.
+  PROTON="${D4R_PROTON:-}"
+  if [[ -z "$PROTON" ]]; then
+    best=-1
+    for d in "$HOME/.local/share/Steam" "$HOME/.steam/root" "$HOME/.steam/steam" \
+             "$HOME/.var/app/com.valvesoftware.Steam/data/Steam"; do
+      for p in "$d"/compatibilitytools.d/GE-Proton11-*; do
+        n="${p##*/GE-Proton11-}"
+        [[ -x "$p/proton" && "$n" =~ ^[0-9]+$ ]] || continue
+        if [[ "$n" == 3 ]]; then best=1000; PROTON="$p"; elif (( n > best )); then best=$n; PROTON="$p"; fi
+      done
+    done
+  fi
+}
+if (( FIND_PROTON )); then find_proton; [[ -z "$PROTON" ]] || printf '%s\n' "$PROTON"; exit 0; fi
 TOOLS="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
 KIT="$TOOLS/models"
 RUNTIME="$(cd -- "${1:-$TOOLS/..}" && pwd)"
@@ -82,21 +105,7 @@ if (( DO_SR )); then
   DLL="$RUNTIME/nvngx_dlss.dll"
   [[ -f "$DLL" && "$(sha "$DLL")" == "$DLSS_SHA256" ]] || fail "Super Resolution models need nvngx_dlss.dll 310.7.0 in $RUNTIME (run install.sh)"
   [[ -f "$RUNTIME/ngx/_nvngx.dll" ]] || fail "missing $RUNTIME/ngx/_nvngx.dll (run install.sh)"
-  # a GE-Proton: D4R_PROTON, else GE-Proton11-3 (the tested one), else the newest stock GE-Proton11-N in Steam's
-  # compatibility tools. Renamed or rebuilt variants (2026-10-14: one with a suffix after the version number) can
-  # fail NGX's CUDA initialisation, so they are only used when named.
-  PROTON="${D4R_PROTON:-}"
-  if [[ -z "$PROTON" ]]; then
-    best=-1
-    for d in "$HOME/.local/share/Steam" "$HOME/.steam/root" "$HOME/.steam/steam" \
-             "$HOME/.var/app/com.valvesoftware.Steam/data/Steam"; do
-      for p in "$d"/compatibilitytools.d/GE-Proton11-*; do
-        n="${p##*/GE-Proton11-}"
-        [[ -x "$p/proton" && "$n" =~ ^[0-9]+$ ]] || continue
-        if [[ "$n" == 3 ]]; then best=1000; PROTON="$p"; elif (( n > best )); then best=$n; PROTON="$p"; fi
-      done
-    done
-  fi
+  find_proton
   [[ -n "$PROTON" && -x "$PROTON/proton" ]] ||
     fail 'no GE-Proton found: set D4R_PROTON=/path/to/GE-Proton11-3 (the folder holding the proton script)'
   STEAM_ROOT="$(dirname -- "$(dirname -- "$PROTON")")"

packaging/d4r.ini

@@ -29,7 +29,7 @@ ShowWatermark = false
 Enable = auto
 ; Independent denoiser presets: auto (game choice), default, D, E (transformer) or F (DLSS 4.5).
 ; E and F through NVIDIA's library need a denoiser DLL containing that model (F: 310.9 or later). On the engine
-; ([Engine] Enabled = true) F runs from the model in d4r\engine\rr-f; frames the library serves instead show
+; ([Engine]) F runs from the model in d4r\engine\rr-f; frames the library serves instead show
 ; preset D when the DLL is older (d4r_nvngx.log says so).
 Model = auto
 
@@ -73,11 +73,13 @@ ElideNgxSync = true
 DirectOutput = auto
 
 [Engine]
-; Experimental. Runs DLSS 4 and 4.5 (models K, L and M) on d4r's own Vulkan inference engine instead of NVIDIA's
-; kernels: the game shows the result of the frame it just rendered and [Latency] / [Interop] do not apply.
-; Needs Mesa RADV with VK_KHR_cooperative_matrix and the models in d4r\engine\k, k-ldr, m, m-ldr, l and l-ldr
-; (see D4R_README.txt). Games or settings it does not cover use the normal path; d4r_nvngx.log says why.
-Enabled = false
+; Runs DLSS 4 and 4.5 (models K, L and M) and Ray Reconstruction (D, E and F) on d4r's own Vulkan inference
+; engine instead of NVIDIA's kernels: the faster path, and the game shows the result of the frame it just rendered
+; ([Latency] / [Interop] do not apply). Needs Mesa RADV with VK_KHR_cooperative_matrix and the models install.sh
+; builds in d4r\engine (k, k-ldr, m, m-ldr, l, l-ldr, rr-d, rr-e, rr-f). Games or settings it does not cover,
+; and a device that cannot run it, use the normal path; d4r_nvngx.log says why.
+; auto = on when d4r\engine holds a model, true / false = always / never.
+Enabled = auto
 ; Another model K folder for games with the HDR flag (a path relative to the d4r folder, or a Windows path
 ; such as Z:\home\me\k)
 ModelDir = auto