From fff96a85280a008e200a959b1e23965495d4ee37 Mon Sep 17 00:00:00 2001
From: "Skyth (Asilkan)"
 <19259897+blueskythlikesclouds@users.noreply.github.com>
Date: Sat, 8 Feb 2025 20:45:14 +0300
Subject: [PATCH] Implement fix for Sparkle locus particle vertex corruption.
 (#317)

---
 UnleashedRecomp/patches/fps_patches.cpp | 8 ++++++++
 UnleashedRecompLib/config/SWA.toml      | 5 +++++
 2 files changed, 13 insertions(+)

diff --git a/UnleashedRecomp/patches/fps_patches.cpp b/UnleashedRecomp/patches/fps_patches.cpp
index 33f4ca2c..9bdb8e9d 100644
--- a/UnleashedRecomp/patches/fps_patches.cpp
+++ b/UnleashedRecomp/patches/fps_patches.cpp
@@ -159,3 +159,11 @@ PPC_FUNC(sub_82B00D00)
 
     *pElapsedTime = std::max(*pElapsedTime, 0.0f);
 }
+
+bool SparkleLocusMidAsmHook()
+{
+    // There is an epsilon check in sparkle locus particle code that seems to never pass at high frame rates, which causes vertex corruption.
+    // Checking for equality doesn't fix it either, so we can fix it by forcing it to always execute instead.
+    // This has the side effect of the locus particle eventually snapping to the rest position during pause, but it's better than vertices exploding.
+    return App::s_deltaTime < (1.0 / 60.0);
+}
diff --git a/UnleashedRecompLib/config/SWA.toml b/UnleashedRecompLib/config/SWA.toml
index 10434e6f..79341805 100644
--- a/UnleashedRecompLib/config/SWA.toml
+++ b/UnleashedRecompLib/config/SWA.toml
@@ -957,3 +957,8 @@ registers = ["r3"]
 name = "EvilHudGuideUpdateMidAsmHook"
 address = 0x82449800
 registers = ["r30", "f30"]
+
+[[midasm_hook]]
+name = "SparkleLocusMidAsmHook"
+address = 0x82E96804
+jump_address_on_true = 0x82E96808