From 0c1bb18a1b345f785553919dbf8cce739193f894 Mon Sep 17 00:00:00 2001
From: baldurk <baldurk@baldurk.org>
Date: Mon, 6 Oct 2025 16:02:54 +0100
Subject: [PATCH] Prepare to remove live<->replay resource id map lookups

* Resources will be given the ID to use on replay in order to match the original
  IDs. Any internal replay-time resources are given the same namespaced IDs as
  before.
* We add a new per-ID query to check if something is replay-only or not.
---
 renderdoc/api/replay/resourceid.h   |  6 ++----
 renderdoc/core/core.cpp             |  2 +-
 renderdoc/core/resource_manager.cpp | 11 +++++++++--
 renderdoc/core/resource_manager.h   |  1 +
 4 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/renderdoc/api/replay/resourceid.h b/renderdoc/api/replay/resourceid.h
index 4786c8648..76e59f18f 100644
--- a/renderdoc/api/replay/resourceid.h
+++ b/renderdoc/api/replay/resourceid.h
@@ -45,10 +45,8 @@ DOCUMENT(R"(This is an opaque identifier that uniquely locates a resource.
 
 .. note::
   These IDs do not overlap ever - textures, buffers, shaders and samplers will all have unique IDs
-  and do not reuse the namespace. Likewise the IDs assigned for resources during capture  are not
-  re-used on replay - the corresponding resources created on replay to stand-in for capture-time
-  resources are given unique IDs and a mapping is stored to between the capture-time resource and
-  the replay-time one.
+  and do not reuse the namespace. The IDs assigned for resources during capture are also used
+  during replay. Any internal/synthesised resources created during replay will have distinct IDs.
 )");
 struct ResourceId
 {
diff --git a/renderdoc/core/core.cpp b/renderdoc/core/core.cpp
index 9e2fe914c..935004e3d 100644
--- a/renderdoc/core/core.cpp
+++ b/renderdoc/core/core.cpp
@@ -104,7 +104,7 @@ rdcstr DoStringise(const ResourceId &el)
   // hardcode empty/null ResourceId to both avoid special case below and fast-path a common case as
   // a string literal.
   if(num == 0)
-    return PREFIX "0";
+    return PREFIX "0"_lit;
 
   // enough for prefix and a 64-bit value in decimal
   char str[48] = {};
diff --git a/renderdoc/core/resource_manager.cpp b/renderdoc/core/resource_manager.cpp
index e27bbfba8..f2706bddd 100644
--- a/renderdoc/core/resource_manager.cpp
+++ b/renderdoc/core/resource_manager.cpp
@@ -30,6 +30,7 @@
 namespace ResourceIDGen
 {
 static int64_t globalIDCounter = 1;
+static ResourceId baseReplayID;
 
 ResourceId GetNewUniqueID()
 {
@@ -38,16 +39,22 @@ ResourceId GetNewUniqueID()
   return ret;
 }
 
+bool IsReplayOnlyID(ResourceId id)
+{
+  return baseReplayID < id;
+}
+
 void SetReplayResourceIDs()
 {
-  // separate replay IDs from live IDs by adding a value when replaying.
-  // 1000000000000000000 live IDs before we overlap replay IDs gives
+  // separate replay-only IDs from captured IDs by adding a value when replaying.
+  // 1000000000000000000 capture-time IDs before we overlap replay IDs gives
   // almost 32 years generating 100000 IDs per frame at 10000 FPS.
 
   // only add this value once (since we're not |'ing on a bit)
   if(globalIDCounter < 1000000000000000000LL)
     globalIDCounter =
         RDCMAX(int64_t(globalIDCounter), int64_t(globalIDCounter + 1000000000000000000LL));
+  baseReplayID = GetNewUniqueID();
 }
 };
 
diff --git a/renderdoc/core/resource_manager.h b/renderdoc/core/resource_manager.h
index a9311f1be..788fb46da 100644
--- a/renderdoc/core/resource_manager.h
+++ b/renderdoc/core/resource_manager.h
@@ -296,6 +296,7 @@ inline bool MarkReferenced(std::unordered_map<ResourceId, FrameRefType> &refs, R
 namespace ResourceIDGen
 {
 ResourceId GetNewUniqueID();
+bool IsReplayOnlyID(ResourceId id);
 void SetReplayResourceIDs();
 };