From bc392ae1087f6cba58d090020ec1b67ca1ce670b Mon Sep 17 00:00:00 2001
From: Narr the Reg <5944268+german77@users.noreply.github.com>
Date: Sun, 12 Apr 2026 12:41:33 -0600
Subject: [PATCH] Boss/Koopa: Implement `KoopaLandPointHolder` (#1010)

---
 data/file_list.yml                      |  14 +--
 src/Boss/Koopa/KoopaLandPointHolder.cpp | 120 ++++++++++++++++++++++++
 src/Boss/Koopa/KoopaLandPointHolder.h   |  32 +++++++
 3 files changed, 159 insertions(+), 7 deletions(-)
 create mode 100644 src/Boss/Koopa/KoopaLandPointHolder.cpp
 create mode 100644 src/Boss/Koopa/KoopaLandPointHolder.h

diff --git a/data/file_list.yml b/data/file_list.yml
index fca53e02..1a4e0f4d 100644
--- a/data/file_list.yml
+++ b/data/file_list.yml
@@ -17145,31 +17145,31 @@ Boss/Koopa/KoopaLandPointHolder.o:
     label:
     - _ZN20KoopaLandPointHolderC1ERKN2al13ActorInitInfoE
     - _ZN20KoopaLandPointHolderC2ERKN2al13ActorInitInfoE
-    status: NotDecompiled
+    status: Matching
   - offset: 0x0956b8
     size: 252
     label: _ZN20KoopaLandPointHolder18decidePointFarFromERKN4sead7Vector3IfEE
-    status: NotDecompiled
+    status: Matching
   - offset: 0x0957b4
     size: 32
     label: _ZN20KoopaLandPointHolder15invalidatePointEi
-    status: NotDecompiled
+    status: Matching
   - offset: 0x0957d4
     size: 452
     label: _ZN20KoopaLandPointHolder24decidePointEitherFarSideERKN4sead7Vector3IfEE
-    status: NotDecompiled
+    status: Matching
   - offset: 0x095998
     size: 252
     label: _ZN20KoopaLandPointHolder19decidePointNearFromERKN4sead7Vector3IfEE
-    status: NotDecompiled
+    status: Matching
   - offset: 0x095a94
     size: 44
     label: _ZN20KoopaLandPointHolder5resetEv
-    status: NotDecompiled
+    status: Matching
   - offset: 0x095ac0
     size: 264
     label: _ZNK20KoopaLandPointHolder21findNearestPointTransERKN4sead7Vector3IfEE
-    status: NotDecompiled
+    status: Matching
 Boss/Koopa/KoopaLv1.o:
   '.text':
   - offset: 0x095bc8
diff --git a/src/Boss/Koopa/KoopaLandPointHolder.cpp b/src/Boss/Koopa/KoopaLandPointHolder.cpp
new file mode 100644
index 00000000..aa15a06d
--- /dev/null
+++ b/src/Boss/Koopa/KoopaLandPointHolder.cpp
@@ -0,0 +1,120 @@
+#include "Boss/Koopa/KoopaLandPointHolder.h"
+
+#include "Library/Math/MathUtil.h"
+#include "Library/Placement/PlacementFunction.h"
+#include "Library/Placement/PlacementInfo.h"
+
+KoopaLandPointHolder::KoopaLandPointHolder(const al::ActorInitInfo& initInfo) {
+    al::getTrans(&mTrans, initInfo);
+    al::getQuat(&mQuat, initInfo);
+    mLandPoints = al::calcLinkChildNum(initInfo, "LandPoint");
+
+    if (mLandPoints <= 0)
+        return;
+
+    mPointsQuat = new sead::Quatf[mLandPoints];
+    mPointsTrans = new sead::Vector3f[mLandPoints];
+    mInvalidPoints = new bool[mLandPoints];
+
+    for (s32 i = 0; i < mLandPoints; i++) {
+        mInvalidPoints[i] = false;
+
+        al::PlacementInfo placementInfo;
+        al::getLinksInfoByIndex(&placementInfo, initInfo, "LandPoint", i);
+        al::getQuat(&mPointsQuat[i], placementInfo);
+        al::getTrans(&mPointsTrans[i], placementInfo);
+    }
+}
+
+inline f32 getKoopaLandPointDistance(const sead::Vector3f& posA, const sead::Vector3f& posB) {
+    sead::Vector3f distance = posA - posB;
+    return sead::Mathf::sqrt(distance.x * distance.x + distance.z * distance.z);
+}
+
+void KoopaLandPointHolder::decidePointFarFrom(const sead::Vector3f& pos) {
+    s32 selectedPoint = -1;
+    f32 maxDistance = 0.0f;
+
+    for (s32 i = 0; i < mLandPoints; i++) {
+        if (mInvalidPoints[i])
+            continue;
+
+        f32 dist = getKoopaLandPointDistance(mPointsTrans[i], pos);
+
+        if (selectedPoint < 0 || maxDistance < dist) {
+            selectedPoint = i;
+            maxDistance = dist;
+        }
+    }
+
+    invalidatePoint(selectedPoint);
+    mCurrentLandPoint = selectedPoint;
+}
+
+void KoopaLandPointHolder::invalidatePoint(s32 index) {
+    mInvalidPoints[index] = true;
+
+    if (mCurrentLandPoint > -1)
+        mInvalidPoints[mCurrentLandPoint] = false;
+}
+
+void KoopaLandPointHolder::decidePointEitherFarSide(const sead::Vector3f& pos) {
+    if (mCurrentLandPoint < 0) {
+        decidePointFarFrom(pos);
+        return;
+    }
+
+    mInvalidPoints[mCurrentLandPoint] = false;
+    s32 prevPoint = al::modi(mCurrentLandPoint - 1 + mLandPoints, mLandPoints);
+    s32 nextPoint = al::modi(mCurrentLandPoint + 1 + mLandPoints, mLandPoints);
+
+    f32 prevDist = getKoopaLandPointDistance(mPointsTrans[prevPoint], pos);
+    f32 nextDist = getKoopaLandPointDistance(mPointsTrans[nextPoint], pos);
+
+    if (prevDist < nextDist)
+        mCurrentLandPoint = nextPoint;
+    else
+        mCurrentLandPoint = prevPoint;
+}
+
+void KoopaLandPointHolder::decidePointNearFrom(const sead::Vector3f& pos) {
+    s32 selectedPoint = -1;
+    f32 minDistance = 0.0f;
+
+    for (s32 i = 0; i < mLandPoints; i++) {
+        if (mInvalidPoints[i])
+            continue;
+
+        f32 dist = getKoopaLandPointDistance(mPointsTrans[i], pos);
+
+        if (selectedPoint < 0 || dist < minDistance) {
+            selectedPoint = i;
+            minDistance = dist;
+        }
+    }
+
+    invalidatePoint(selectedPoint);
+    mCurrentLandPoint = selectedPoint;
+}
+
+void KoopaLandPointHolder::reset() {
+    for (s32 i = 0; i < mLandPoints; i++)
+        mInvalidPoints[i] = false;
+}
+
+// NOTE: does not care about `mInvalidPoints`
+const sead::Vector3f& KoopaLandPointHolder::findNearestPointTrans(const sead::Vector3f& pos) const {
+    f32 minDistance = getKoopaLandPointDistance(mPointsTrans[0], pos);
+    s32 selectedPoint = 0;
+
+    for (s32 i = 1; i < mLandPoints; i++) {
+        f32 dist = getKoopaLandPointDistance(mPointsTrans[i], pos);
+
+        if (dist < minDistance) {
+            selectedPoint = i;
+            minDistance = dist;
+        }
+    }
+
+    return mPointsTrans[selectedPoint];
+}
diff --git a/src/Boss/Koopa/KoopaLandPointHolder.h b/src/Boss/Koopa/KoopaLandPointHolder.h
new file mode 100644
index 00000000..1e1ee277
--- /dev/null
+++ b/src/Boss/Koopa/KoopaLandPointHolder.h
@@ -0,0 +1,32 @@
+#pragma once
+
+#include <basis/seadTypes.h>
+#include <math/seadQuat.h>
+#include <math/seadVector.h>
+
+namespace al {
+struct ActorInitInfo;
+}  // namespace al
+
+class KoopaLandPointHolder {
+public:
+    KoopaLandPointHolder(const al::ActorInitInfo& initInfo);
+
+    void decidePointFarFrom(const sead::Vector3f& pos);
+    void invalidatePoint(s32 index);
+    void decidePointEitherFarSide(const sead::Vector3f& pos);
+    void decidePointNearFrom(const sead::Vector3f& pos);
+    void reset();
+    const sead::Vector3f& findNearestPointTrans(const sead::Vector3f& pos) const;
+
+private:
+    sead::Vector3f mTrans = {0.0f, 0.0f, 0.0f};
+    sead::Quatf mQuat = sead::Quatf::unit;
+    s32 mCurrentLandPoint = -1;
+    s32 mLandPoints = 0;
+    sead::Quatf* mPointsQuat = nullptr;
+    sead::Vector3f* mPointsTrans = nullptr;
+    bool* mInvalidPoints = nullptr;
+};
+
+static_assert(sizeof(KoopaLandPointHolder) == 0x40);