diff --git a/src/JSystem/JAudio2/JAUSeqDataBlockMgr.cpp b/src/JSystem/JAudio2/JAUSeqDataBlockMgr.cpp
index df8741a191..039137ff5d 100644
--- a/src/JSystem/JAudio2/JAUSeqDataBlockMgr.cpp
+++ b/src/JSystem/JAudio2/JAUSeqDataBlockMgr.cpp
@@ -114,7 +114,7 @@ bool JAUDynamicSeqDataBlocks::appendDynamicSeqDataBlock(JAUSeqDataBlock* seqData
 static void JAUDynamicSeqDataBlocks_receiveLoaded_(u32 param_0, u32 param_1) {
     JSULink<JAUSeqDataBlock>* link = (JSULink<JAUSeqDataBlock>*)param_1;
     JAUSeqDataBlock* seqDataBlock = link->getObject();
-    if (param_0 != NULL) {
+    if (param_0 != 0) {
         seqDataBlock->field_0x1c = 2;
     } else {
         seqDataBlock->field_0x1c = 0;
diff --git a/src/Z2AudioLib/Z2Audience.cpp b/src/Z2AudioLib/Z2Audience.cpp
index 46b7107473..5e8522701b 100644
--- a/src/Z2AudioLib/Z2Audience.cpp
+++ b/src/Z2AudioLib/Z2Audience.cpp
@@ -454,7 +454,7 @@ f32 Z2SpotMic::calcMicVolume(f32 param_0, int camID, f32 param_2) {
     JUT_ASSERT(687, camID >= 0);
     JUT_ASSERT(688, camID < 1);
 
-    if (mMicOn == NULL) {
+    if (mMicOn == false) {
         return param_2;
     }
 
diff --git a/src/Z2AudioLib/Z2Creature.cpp b/src/Z2AudioLib/Z2Creature.cpp
index e02d1abcd5..14b0d31023 100644
--- a/src/Z2AudioLib/Z2Creature.cpp
+++ b/src/Z2AudioLib/Z2Creature.cpp
@@ -718,11 +718,11 @@ void Z2SoundObjBeeGroup::playBeeGroupSound(JAISoundID soundID, u8 param_1) {
     Z2SoundHandlePool* handle1 = startLevelSound((u32)soundID, 0, -1);
     Z2SoundHandlePool* handle2 = startLevelSound(sound_id2, 0, -1);
 
-    if (handle1 != NULL && *handle1 != NULL) {
+    if (handle1 != NULL && *handle1 != false) {
         f32 volume = Z2Calc::linearTransform(param_1, 1.0f, 5.0f, 0.5f, 1.0f, false);
         (*handle1)->getAuxiliary().moveVolume(volume, 0);
     }
-    if (handle2 != NULL && *handle2 != NULL) {
+    if (handle2 != NULL && *handle2 != false) {
         f32 volume = Z2Calc::linearTransform(param_1, 1.0f, 20.0f, 0.1f, 1.0f, false);
         (*handle2)->getAuxiliary().moveVolume(volume, 0);
     }
@@ -924,28 +924,28 @@ Z2SoundHandlePool* Z2CreatureOI::startCreatureSoundLevel(JAISoundID soundID, u32
         f32 pitch = Z2Calc::getParamByExp(mapinfo, 0.0f, 42.0f, 0.4f, 0.9f, 1.1f,
                                           Z2Calc::CURVE_POSITIVE);
         
-        if (handle1 != NULL && *handle1 != NULL) {
+        if (handle1 != NULL && *handle1 != false) {
             (*handle1)->getAuxiliary().moveVolume(volume, 0);
             (*handle1)->getAuxiliary().movePitch(pitch, 0);
         } else {
             return NULL;
         }
 
-        if (handle2 != NULL && *handle2 != NULL) {
+        if (handle2 != NULL && *handle2 != false) {
             (*handle2)->getAuxiliary().moveVolume(volume, 0);
             (*handle2)->getAuxiliary().movePitch(pitch, 0);
         } else {
             return NULL;
         }
 
-        if (handle3 != NULL && *handle3 != NULL) {
+        if (handle3 != NULL && *handle3 != false) {
             (*handle3)->getAuxiliary().moveVolume(volume, 0);
             (*handle3)->getAuxiliary().movePitch(pitch, 0);
         } else {
             return NULL;
         }
 
-        if (handle4 != NULL && *handle4 != NULL) {
+        if (handle4 != NULL && *handle4 != false) {
             (*handle4)->getAuxiliary().moveVolume(volume, 0);
             (*handle4)->getAuxiliary().movePitch(pitch, 0);
             return handle4;
@@ -979,7 +979,7 @@ Z2SoundHandlePool* Z2CreatureOI::startTentacleSoundLevel(JAISoundID soundID, u8
 }
 
 static void Z2_E_sw_modPitch(Z2SoundHandlePool* handle, u32 mapinfo) {
-    if (handle != NULL && *handle != NULL) {
+    if (handle != NULL && *handle != false) {
         f32 pitch = 1.0f;
         switch (mapinfo) {
         case 1:
@@ -994,7 +994,7 @@ static void Z2_E_sw_modPitch(Z2SoundHandlePool* handle, u32 mapinfo) {
 }
 
 static void Z2_E_ms_modVol(Z2SoundHandlePool* handle, u32 mapinfo) {
-    if (handle != NULL && *handle != NULL) {
+    if (handle != NULL && *handle != false) {
         f32 var_f31 = 0.2f;
         if (mapinfo == 1) {
             (*handle)->getAuxiliary().moveVolume(var_f31, 0);
@@ -1003,7 +1003,7 @@ static void Z2_E_ms_modVol(Z2SoundHandlePool* handle, u32 mapinfo) {
 }
 
 static void Z2_E_mm_modPitch(Z2SoundHandlePool* handle, u32 mapinfo) {
-    if (handle != NULL && *handle != NULL) {
+    if (handle != NULL && *handle != false) {
         f32 var_f31 = 0.7f;
         if (mapinfo == 3) {
             (*handle)->getAuxiliary().movePitch(var_f31, 0);
@@ -1012,7 +1012,7 @@ static void Z2_E_mm_modPitch(Z2SoundHandlePool* handle, u32 mapinfo) {
 }
 
 static void Z2_B_zan_modPitch(Z2SoundHandlePool* handle, u32 mapinfo) {
-    if (handle != NULL && *handle != NULL) {
+    if (handle != NULL && *handle != false) {
         f32 pitch = 1.0f;
         f32 volume = 1.0f;
         if (mapinfo > 400) {
diff --git a/src/Z2AudioLib/Z2SoundObject.cpp b/src/Z2AudioLib/Z2SoundObject.cpp
index a3b8b4c88a..69b0dc3bad 100644
--- a/src/Z2AudioLib/Z2SoundObject.cpp
+++ b/src/Z2AudioLib/Z2SoundObject.cpp
@@ -164,7 +164,7 @@ Z2SoundHandlePool* Z2SoundObjBase::startLevelSound(JAISoundID soundID, u32 mapin
         if (handle != NULL) {
             soundStarter_->startSound(soundID, handle, pos_, mapinfo, fxMix,
                                       1.0f, 1.0f, -1.0f, -1.0f, 0);
-            if (handle != NULL && (*handle) != NULL) {
+            if (handle != NULL && (*handle) != false) {
                 (*handle)->setLifeTime(1, false);
 
                 #if PLATFORM_WII || PLATFORM_SHIELD
@@ -210,7 +210,7 @@ Z2SoundHandlePool* Z2SoundObjBase::startCollisionSE(u32 hitID, u32 mapinfo, Z2So
     }
 
     Z2SoundHandlePool* handle = Z2SoundObjBase::startSound(JAISoundID(hitID), mapinfo, -1);
-    if (handle != NULL && (*handle) != NULL) {
+    if (handle != NULL && (*handle) != false) {
         (*handle)->setUserData(mapinfo);
         if (30 <= mapinfo && mapinfo <= 52) {
             Z2Audible* audible = (Z2Audible*)(*handle)->getAudible();
@@ -251,7 +251,7 @@ Z2SoundHandlePool* Z2DopplerSoundObjBase::startSound(JAISoundID soundID, u32 map
     pos_ = NULL;
 
     Z2SoundHandlePool* handle = Z2SoundObjBase::startSound(soundID, mapinfo, reverb);
-    if (pos != NULL && handle != NULL && (*handle) != NULL) {
+    if (pos != NULL && handle != NULL && (*handle) != false) {
         if ((*handle)->acceptsNewAudible()) {
             (*handle)->newAudible(*pos, &field_0x20, 0, NULL);
         }
@@ -266,7 +266,7 @@ Z2SoundHandlePool* Z2DopplerSoundObjBase::startLevelSound(JAISoundID soundID, u3
     pos_ = NULL;
 
     Z2SoundHandlePool* handle = Z2SoundObjBase::startLevelSound(soundID, mapinfo, reverb);
-    if (pos != NULL && handle != NULL && (*handle) != NULL) {
+    if (pos != NULL && handle != NULL && (*handle) != false) {
         if ((*handle)->acceptsNewAudible()) {
             (*handle)->newAudible(*pos, &field_0x20, 0, NULL);
         }
@@ -285,7 +285,7 @@ void Z2SoundObjSimple::init(Vec* posPtr, u8 handleNum) {
 Z2SoundHandlePool* Z2SoundObjSimple::startSound(JAISoundID soundID, u32 mapinfo, s8 reverb) {
     Z2SoundHandlePool* handle = Z2SoundObjBase::startSound(soundID, mapinfo, reverb);
 
-    if (soundID == Z2SE_AL_UKI_POKOPOKO && handle != NULL && (*handle) != NULL) {
+    if (soundID == Z2SE_AL_UKI_POKOPOKO && handle != NULL && (*handle) != false) {
         f32 volume = Z2Calc::getParamByExp((f32)mapinfo, 0.0f, 127.0f, 0.2f, 0.4f, 1.0f, Z2Calc::CURVE_POSITIVE);
         f32 pitch = Z2Calc::getParamByExp((f32)mapinfo, 0.0f, 127.0f, 0.2f, 0.6f, 1.2f, Z2Calc::CURVE_POSITIVE);
         (*handle)->getAuxiliary().movePitch(pitch, 0);
@@ -298,7 +298,7 @@ Z2SoundHandlePool* Z2SoundObjSimple::startSound(JAISoundID soundID, u32 mapinfo,
 Z2SoundHandlePool* Z2SoundObjSimple::startLevelSound(JAISoundID soundID, u32 mapinfo, s8 reverb) {
     Z2SoundHandlePool* handle = Z2SoundObjBase::startLevelSound(soundID, mapinfo, reverb);
 
-    if (handle != NULL && (*handle) != NULL) {
+    if (handle != NULL && (*handle) != false) {
         f32 pitch = 1.0f;
         f32 volume = 1.0f;
         switch (soundID) {
@@ -502,7 +502,7 @@ void Z2SoundObjAnime::startSoundInner(const JGeometry::TVec3<f32>& pos, f32 para
         u32 id = getSoundID(animationSound, pos, param_1);
         if (!Z2GetSeMgr()->isSoundCulling(id)) {
             JAISoundHandle* handle = getHandleUserData(user_data);
-            if (handle != NULL && (*handle) != NULL && (*handle)->getAnimationState() != 1) {
+            if (handle != NULL && (*handle) != false && (*handle)->getAnimationState() != 1) {
                 handle = NULL;
             }
 
@@ -514,7 +514,7 @@ void Z2SoundObjAnime::startSoundInner(const JGeometry::TVec3<f32>& pos, f32 para
                 bool result = soundStarter->startSound(id, handle, &pos, mapinfo, (f32)reverb / 127.0f,
                                                        animationSound->field_0x0c, (f32)animationSound->field_0x14 / 127.0f,
                                                        -1.0f, -1.0f, 0);
-                if ((*handle) != NULL) {
+                if ((*handle) != false) {
                     (*handle)->setAnimationState(1);
                     (*handle)->setUserData(user_data);
                     if (animationSound->setsLifeTime()) {
diff --git a/src/c/c_dylink.cpp b/src/c/c_dylink.cpp
index a9e023318b..2d47e2df7a 100644
--- a/src/c/c_dylink.cpp
+++ b/src/c/c_dylink.cpp
@@ -916,7 +916,7 @@ BOOL cCc_Check() {
     BOOL rt = TRUE;
     for (int i = 0; i < ARRAY_SIZEU(DynamicNameTable); i++) {
         uintptr_t ptr = (uintptr_t)DMC[i];
-        if (ptr != NULL) {
+        if (ptr != 0) {
             u32 ptr_hi_byte = ptr >> 0x18;
             if (ptr_hi_byte < 0x80 || ptr_hi_byte > 0x83) {
                 // "cCc_Check invalid pointer detected"
diff --git a/src/d/actor/d_a_alink.cpp b/src/d/actor/d_a_alink.cpp
index aed6026b10..5f6bd7ca17 100644
--- a/src/d/actor/d_a_alink.cpp
+++ b/src/d/actor/d_a_alink.cpp
@@ -3082,7 +3082,7 @@ cXyz* daAlink_c::getNeckAimPos(cXyz* param_0, int* param_1, int param_2) {
             }
         } else if (field_0x35c4.abs2XZ() > 1.0f && checkModeFlg(1)) {
             f32 var_f31;
-            if (checkWolf() != NULL) {
+            if (checkWolf() != 0) {
                 var_f31 = 80.0f;
             } else {
                 var_f31 = 150.0f;
diff --git a/src/d/actor/d_a_coach_fire.cpp b/src/d/actor/d_a_coach_fire.cpp
index 80433c573e..f2f46b9eab 100644
--- a/src/d/actor/d_a_coach_fire.cpp
+++ b/src/d/actor/d_a_coach_fire.cpp
@@ -113,11 +113,11 @@ int daCoachFire_c::execute() {
         dAttention_c* attn = dComIfGp_getAttention();
         if (attn->LockonTruth()) {
             if (attn->LockonTarget(0) != this) {
-                if (coach->deleteFireArrowFromList(fopAcM_GetID(this)) != NULL) {
+                if (coach->deleteFireArrowFromList(fopAcM_GetID(this)) != false) {
                     fopAcM_delete(this);
                 }
             }
-        } else if (coach->deleteFireArrowFromList(fopAcM_GetID(this)) != NULL) {
+        } else if (coach->deleteFireArrowFromList(fopAcM_GetID(this)) != false) {
             fopAcM_delete(this);
         }
     }
diff --git a/src/d/actor/d_a_door_shutter.cpp b/src/d/actor/d_a_door_shutter.cpp
index 66441fb197..d47c4c9c3c 100644
--- a/src/d/actor/d_a_door_shutter.cpp
+++ b/src/d/actor/d_a_door_shutter.cpp
@@ -1380,7 +1380,7 @@ int daDoor20_c::createKey() {
             }
             field_0x5ec =
                 fopAcM_createChildFromOffset(PROC_Obj_Lv5Key, fopAcM_GetID(this), 0xffffffff,
-                                             &cStack_28, roomNo, &cStack_30, &scale, 0xffffffff, 0);
+                                             &cStack_28, roomNo, &cStack_30, &scale, -1, 0);
             break;
         default:
             OSReport_Error("シャッタードア：鍵タイプが不明です\n"); // Shutter door: key type unknown
@@ -1399,7 +1399,7 @@ int daDoor20_c::createKey() {
             }
             field_0x5ec =
                 fopAcM_createChildFromOffset(PROC_OBJ_KEYHOLE, fopAcM_GetID(this), 0xffffffff,
-                                             &cStack_28, roomNo, &cStack_30, &scale, 0xffffffff, 0);
+                                             &cStack_28, roomNo, &cStack_30, &scale, -1, 0);
         }
 
         current.pos = prevPos;
diff --git a/src/d/actor/d_a_e_arrow.cpp b/src/d/actor/d_a_e_arrow.cpp
index a62958bca3..b3d1a7b26e 100644
--- a/src/d/actor/d_a_e_arrow.cpp
+++ b/src/d/actor/d_a_e_arrow.cpp
@@ -330,7 +330,7 @@ static void e_arrow_spin(e_arrow_class* i_this) {
 }
 
 static void* s_limit_sub(void* i_actor, void* i_data) {
-    if (fopAcM_IsActor(i_actor) != NULL && i_actor != i_data &&
+    if (fopAcM_IsActor(i_actor) != FALSE && i_actor != i_data &&
         fopAcM_GetName(i_actor) == PROC_E_ARROW &&
         static_cast<e_arrow_class*>(i_actor)->mAction == ACTION_ARROW_FIRE &&
         fabsf(static_cast<e_arrow_class*>(i_actor)->field_0xa00.z -
diff --git a/src/d/actor/d_a_e_bg.cpp b/src/d/actor/d_a_e_bg.cpp
index be19dfcae2..9c8320c188 100644
--- a/src/d/actor/d_a_e_bg.cpp
+++ b/src/d/actor/d_a_e_bg.cpp
@@ -93,7 +93,7 @@ int daE_BG_c::ctrlJoint(J3DJoint* i_joint, J3DModel* i_model) {
 }
 
 int daE_BG_c::JointCallBack(J3DJoint* i_joint, int param_1) {
-    if (param_1 == NULL) {
+    if (param_1 == 0) {
         J3DModel* model = j3dSys.getModel();
         daE_BG_c* bg = (daE_BG_c*)model->getUserArea();
         if (bg != NULL) {
diff --git a/src/d/actor/d_a_e_df.cpp b/src/d/actor/d_a_e_df.cpp
index cd1fd1b187..9ae161b968 100644
--- a/src/d/actor/d_a_e_df.cpp
+++ b/src/d/actor/d_a_e_df.cpp
@@ -659,7 +659,7 @@ int daE_DF_c::Create() {
             return cPhs_ERROR_e;
         }
 
-        if (fopAcM_entrySolidHeap(this, useHeapInit, 0x1a40) == NULL) {
+        if (fopAcM_entrySolidHeap(this, useHeapInit, 0x1a40) == false) {
             return cPhs_ERROR_e;
         }
 
diff --git a/src/d/actor/d_a_e_gi.cpp b/src/d/actor/d_a_e_gi.cpp
index 4dac5344b4..cfdcd94442 100644
--- a/src/d/actor/d_a_e_gi.cpp
+++ b/src/d/actor/d_a_e_gi.cpp
@@ -93,7 +93,7 @@ int daE_GI_c::ctrlJoint(J3DJoint* i_joint, J3DModel* i_model) {
 }
 
 int daE_GI_c::JointCallBack(J3DJoint* i_joint, int param_1) {
-    if (param_1 == NULL) {
+    if (param_1 == 0) {
         J3DModel* model = j3dSys.getModel();
         daE_GI_c* a_this = (daE_GI_c*)model->getUserArea();
         
diff --git a/src/d/actor/d_a_e_hp.cpp b/src/d/actor/d_a_e_hp.cpp
index a1f202489a..114ca27387 100644
--- a/src/d/actor/d_a_e_hp.cpp
+++ b/src/d/actor/d_a_e_hp.cpp
@@ -119,7 +119,7 @@ int daE_HP_c::ctrlJoint(J3DJoint* i_joint, J3DModel* i_model) {
 }
 
 int daE_HP_c::JointCallBack(J3DJoint* i_joint, int param_1) {
-    if (param_1 == NULL) {
+    if (param_1 == 0) {
         J3DModel* model = j3dSys.getModel();
         daE_HP_c* poe = (daE_HP_c*)model->getUserArea();
         if (poe != NULL) {
@@ -155,7 +155,7 @@ int daE_HP_c::LampCtrlJoint(J3DJoint* i_joint, J3DModel* i_model) {
 }
 
 int daE_HP_c::LampJointCallBack(J3DJoint* i_joint, int param_1) {
-    if (param_1 == NULL) {
+    if (param_1 == 0) {
         J3DModel* model = j3dSys.getModel();
         daE_HP_c* poe = (daE_HP_c*)model->getUserArea();
         if (poe != NULL) {
diff --git a/src/d/actor/d_a_formation_mng.cpp b/src/d/actor/d_a_formation_mng.cpp
index 531172731b..70535c25ff 100644
--- a/src/d/actor/d_a_formation_mng.cpp
+++ b/src/d/actor/d_a_formation_mng.cpp
@@ -382,7 +382,7 @@ void daFmtMng_c::create_init() {
     for (int i = 0; i < mFormationLine * mFormationRow; i++, member++) {
         member->mNpcId = fopAcM_createChild(0x294, fopAcM_GetID(this), (inTime << 0x10) | 0x200,
                                                 &member->field_0x04, fopAcM_GetRoomNo(this),
-                                                &home.angle, NULL, 0xffffffff, NULL);
+                                                &home.angle, NULL, -1, NULL);
     }
 }
 
diff --git a/src/d/actor/d_a_kago.cpp b/src/d/actor/d_a_kago.cpp
index c2d2d8b489..9f4dd6e463 100644
--- a/src/d/actor/d_a_kago.cpp
+++ b/src/d/actor/d_a_kago.cpp
@@ -188,7 +188,7 @@ bool daKago_c::checkBck(int param_0) {
 }
 
 int daKago_c::draw() {
-    if (field_0x6de == NULL) {
+    if (field_0x6de == 0) {
         return 1;
     }
 
@@ -692,7 +692,7 @@ int daKago_c::setSceneChange(int param_0) {
 
 void daKago_c::createBalloonScore() {
     if (field_0x6e7 != 0 && mBalloon2DId == fpcM_ERROR_PROCESS_ID_e) {
-        mBalloon2DId = fopAcM_create(PROC_BALLOON2D, 0, 0, 0xffffffff, 0, 0, 0xffffffff);
+        mBalloon2DId = fopAcM_create(PROC_BALLOON2D, 0, 0, 0xffffffff, 0, 0, -1);
         field_0x6e9 = 1;
     }
 }
@@ -1199,7 +1199,7 @@ void daKago_c::executeFly() {
         }
         if (field_0x744 == 3) {
             cLib_chaseUC(&field_0x6de, 0, 4);
-            cLib_addCalcAngleS(&current.angle.x, 0xffffe000, 8, 0x100, 0x10);
+            cLib_addCalcAngleS(&current.angle.x, -8192, 8, 0x100, 0x10);
         } else {
             cLib_addCalcAngleS(&current.angle.x, unkInt2, 8, 0x100, 0x10);
         }
@@ -2230,7 +2230,7 @@ bool daKago_c::PerchDemoAwayForward() {
         if (field_0x728 < 30) {
             cLib_addCalcAngleS(&current.angle.x, 0, 8, 0x100, 0x40);
         } else {
-            cLib_addCalcAngleS(&current.angle.x, 0xffffe000, 8, 0x100, 0x40);
+            cLib_addCalcAngleS(&current.angle.x, -8192, 8, 0x100, 0x40);
         }
 
         shape_angle.x = current.angle.x;
@@ -2277,7 +2277,7 @@ bool daKago_c::PerchDemoAwayForward() {
 
         cLib_chaseF(&field_0x6f8, 30.0f, 1.0f);
 
-        cLib_addCalcAngleS(&current.angle.x, 0xffffe000, 8, 0x100, 0x40);
+        cLib_addCalcAngleS(&current.angle.x, -8192, 8, 0x100, 0x40);
         shape_angle.x = current.angle.x;
         shape_angle.y = current.angle.y;
 
@@ -2547,7 +2547,7 @@ bool daKago_c::executeFirstDemo() {
 
         if (field_0x728 > 30) {
             cLib_chaseF(&field_0x6cc, 350.0f, 4.0f);
-            cLib_addCalcAngleS(&field_0x718, 0xfffff800, 8, 0x100, 0x10);
+            cLib_addCalcAngleS(&field_0x718, -2048, 8, 0x100, 0x10);
         } else {
             cLib_chaseF(&field_0x6cc, 350.0f, 6.0f);
             cLib_addCalcAngleS(&field_0x718, 0x400, 8, 0x200, 0x10);
@@ -2699,7 +2699,7 @@ bool daKago_c::executeFirstDemo() {
     case 6:
         dComIfGp_getEvent()->setSkipProc(this, DemoSkipCallBack, 2);
 
-        cLib_addCalcAngleS(&current.angle.x, 0xffffe000, 8, 0x100, 0x40);
+        cLib_addCalcAngleS(&current.angle.x, -8192, 8, 0x100, 0x40);
         shape_angle.x = current.angle.x;
         shape_angle.y = current.angle.y;
 
@@ -2944,7 +2944,7 @@ void daKago_c::executeLandingLakeHairia() {
         speedF = field_0x6f8 * std::abs(cM_scos(current.angle.x));
         speed.y = -field_0x6f8 * cM_ssin(current.angle.x);
 
-        cLib_chaseAngleS(&shape_angle.x, 0xffffe000, 0x100);
+        cLib_chaseAngleS(&shape_angle.x, -8192, 0x100);
         current.angle.x = shape_angle.x;
 
         if (field_0x728 == 90) {
@@ -3078,7 +3078,7 @@ void daKago_c::executeLandingBoartHouse() {
         speedF = field_0x6f8 * std::abs(cM_scos(current.angle.x));
         speed.y = -field_0x6f8 * cM_ssin(current.angle.x);
 
-        cLib_chaseAngleS(&shape_angle.x, 0xffffe000, 0x100);
+        cLib_chaseAngleS(&shape_angle.x, -8192, 0x100);
         current.angle.x = shape_angle.x;
 
         if (field_0x728 == 0x50) {
@@ -3391,7 +3391,7 @@ void daKago_c::setDashBlurEffect(int param_0) {
         field_0x6be.y = shape_angle.y;
         field_0x6be.z = 0;
     }
-    field_0xb40 = dComIfGp_particle_set(field_0xb40, 0x860f, &cameraEyeOffset, &tevStr, &field_0x6be, 0, 0xff, 0, 0xffffffff, 0, 0, 0);
+    field_0xb40 = dComIfGp_particle_set(field_0xb40, 0x860f, &cameraEyeOffset, &tevStr, &field_0x6be, 0, 0xff, 0, -1, 0, 0, 0);
 }
 
 void daKago_c::setWallHitEffect(cXyz param_0, int param_1) {
@@ -3422,7 +3422,7 @@ void daKago_c::setSibukiEffect() {
     for (int i = 0; i < 3; i++) {
         field_0xb44[i] =
             dComIfGp_particle_set(field_0xb44[i], kago_wave_id[i], &acStack_28, &tevStr, &cStack_30,
-                                  0, 0xff, 0, 0xffffffff, 0, 0, 0);
+                                  0, 0xff, 0, -1, 0, 0, 0);
     }
 
     if (field_0x6e7 == 0) {
@@ -3436,7 +3436,7 @@ void daKago_c::setDashSibukiEffect() {
     cXyz acStack_20(current.pos.x, field_0x70c + l_HIO.mYOffsetFromWaterSurface, current.pos.z);
     csXyz cStack_28(0, shape_angle.y, 0);
     field_0xb50 = dComIfGp_particle_set(field_0xb50, 0x86fe, &acStack_20, &tevStr, &cStack_28, 0,
-                                        0xff, 0, 0xffffffff, 0, 0, 0);
+                                        0xff, 0, -1, 0, 0, 0);
 }
 
 void daKago_c::setWaterFallEffect() {
@@ -3450,7 +3450,7 @@ void daKago_c::setWaterFallEffect() {
     for (int i = 0; i < 2; i++) {
         field_0xb44[i] =
             dComIfGp_particle_set(field_0xb44[i], kago_wave_id[i], &acStack_28, &tevStr, &cStack_30,
-                                  0, 0xff, 0, 0xffffffff, 0, 0, 0);
+                                  0, 0xff, 0, -1, 0, 0, 0);
     }
     if (field_0x6e7 == 0) {
         mSound.startCreatureSoundLevel(Z2SE_EN_YC_SPLASH, 0, -1);
@@ -3734,7 +3734,7 @@ int daKago_c::ctrlJoint(J3DJoint* param_0, J3DModel* param_1) {
 }
 
 int daKago_c::JointCallBack(J3DJoint* param_0, int param_1) {
-    if (param_1 == NULL) {
+    if (param_1 == 0) {
         J3DModel* model = j3dSys.getModel();
         daKago_c* kago = (daKago_c*)model->getUserArea();
         if (kago != NULL) {
diff --git a/src/d/actor/d_a_nbomb.cpp b/src/d/actor/d_a_nbomb.cpp
index 5090950574..48d785a7ce 100644
--- a/src/d/actor/d_a_nbomb.cpp
+++ b/src/d/actor/d_a_nbomb.cpp
@@ -97,7 +97,7 @@ int daNbomb_c::searchEnemy(fopAc_ac_c* i_enemy) {
 
 static void* daNbomb_searchEnemy(fopAc_ac_c* i_actor, void* i_data) {
     if (fopAcM_GetGroup(i_actor) == fopAc_ENEMY_e &&
-        ((daNbomb_c*)i_data)->searchEnemy(i_actor) != NULL)
+        ((daNbomb_c*)i_data)->searchEnemy(i_actor) != 0)
     {
         return i_actor;
     }
diff --git a/src/d/actor/d_a_npc_chin.cpp b/src/d/actor/d_a_npc_chin.cpp
index 500ff60eaa..6fc9002f1a 100644
--- a/src/d/actor/d_a_npc_chin.cpp
+++ b/src/d/actor/d_a_npc_chin.cpp
@@ -362,7 +362,7 @@ int daNpcChin_c::CreateHeap() {
 
     setMotionAnm(motionAnmParam, 0.0f);
 
-    if (field_0xe24 != 0 && mSpotLight.loadModel() == NULL) {
+    if (field_0xe24 != 0 && mSpotLight.loadModel() == 0) {
         return 0;
     }
 
@@ -439,7 +439,7 @@ int daNpcChin_c::createHeapCallBack(fopAc_ac_c* i_this) {
 }
 
 int daNpcChin_c::ctrlJointCallBack(J3DJoint* i_joint, int param_1) {
-    if (param_1 == NULL) {
+    if (param_1 == 0) {
         J3DModel* model = j3dSys.getModel();
         daNpcChin_c* chin = (daNpcChin_c*)model->getUserArea();
         if (chin != NULL) {
diff --git a/src/d/actor/d_a_npc_hanjo.cpp b/src/d/actor/d_a_npc_hanjo.cpp
index 06dc3c57a7..e80428e355 100644
--- a/src/d/actor/d_a_npc_hanjo.cpp
+++ b/src/d/actor/d_a_npc_hanjo.cpp
@@ -1791,7 +1791,7 @@ int daNpc_Hanjo_c::takayose(void* param_0) {
                 }
             }
         }
-        if (daPy_py_c::checkNowWolf() && mCyl2.ChkCoHit() != NULL) {
+        if (daPy_py_c::checkNowWolf() && mCyl2.ChkCoHit() != 0) {
             if (!daPy_getPlayerActorClass()->checkPlayerFly() ||
                 daPy_getPlayerActorClass()->checkAutoJump() ||
                 daPy_getPlayerActorClass()->checkWolfTriggerJump())
diff --git a/src/d/actor/d_a_npc_henna.cpp b/src/d/actor/d_a_npc_henna.cpp
index 0eef1094f7..2991eaa6e6 100644
--- a/src/d/actor/d_a_npc_henna.cpp
+++ b/src/d/actor/d_a_npc_henna.cpp
@@ -2498,7 +2498,7 @@ static int daNpc_Henna_Execute(npc_henna_class* i_this) {
                     mDoMtx_stack_c::transS(-460.0f + AREG_F(0), 51.0f + AREG_F(1),
                                            -240.0f + AREG_F(2));
                     mDoMtx_stack_c::YrotM(-17729 + AREG_S(0));
-                    mDoMtx_stack_c::XrotM(AREG_S(1) - 0x8107);
+                    mDoMtx_stack_c::XrotM((s16)(AREG_S(1) - 0x8107));
                     mDoMtx_stack_c::ZrotM(AREG_S(2) + 2000 + sp_0xe);
                 } else {
                     mDoMtx_stack_c::transS(-790.0f + AREG_F(0), 153.0f + AREG_F(1),
diff --git a/src/d/actor/d_a_npc_kn.cpp b/src/d/actor/d_a_npc_kn.cpp
index 6a6568f9d5..1197e744ce 100644
--- a/src/d/actor/d_a_npc_kn.cpp
+++ b/src/d/actor/d_a_npc_kn.cpp
@@ -4965,7 +4965,7 @@ int daNpc_Kn_c::setPrtcl() {
                                                   mParticleMngr[i].mpModel == true ? &mParticleMngr[i].mAngle : NULL,
                                                   0, fopAcM_GetRoomNo(this), 0.0f, speedF);
 
-        if (mParticleMngr[i].mpModel != NULL) {
+        if (mParticleMngr[i].mpModel != false) {
             emitter = mParticleMngr[i].mManager.getCenterEmitter(0, 0);
             if (emitter != NULL) {
                 switch (i) {
diff --git a/src/d/actor/d_a_npc_rafrel.cpp b/src/d/actor/d_a_npc_rafrel.cpp
index 1b897adfaa..cc9b2382d9 100644
--- a/src/d/actor/d_a_npc_rafrel.cpp
+++ b/src/d/actor/d_a_npc_rafrel.cpp
@@ -421,7 +421,7 @@ int daNpcRafrel_c::createHeapCallBack(fopAc_ac_c* i_this) {
 }
 
 int daNpcRafrel_c::ctrlJointCallBack(J3DJoint* i_joint, int param_1) {
-    if (param_1 == NULL) {
+    if (param_1 == 0) {
         J3DModel* mdl_p = j3dSys.getModel();
         daNpcRafrel_c* i_this = (daNpcRafrel_c*)mdl_p->getUserArea();
 
diff --git a/src/d/actor/d_a_npc_tk.cpp b/src/d/actor/d_a_npc_tk.cpp
index 09e5a64514..8b83afb997 100644
--- a/src/d/actor/d_a_npc_tk.cpp
+++ b/src/d/actor/d_a_npc_tk.cpp
@@ -1340,7 +1340,7 @@ void daNPC_TK_c::executeBack() {
                 if (current.pos.y > unkXyz1.y) {
                     cLib_chaseAngleS(&shape_angle.x, 0x2000, 0x400);
                 } else {
-                    cLib_chaseAngleS(&shape_angle.x, 0xffffe000, 0x400);
+                    cLib_chaseAngleS(&shape_angle.x, -8192, 0x400);
                 }
             } else {
                 cLib_chaseAngleS(&field_0x69c, 0x200, 0x10);
@@ -1379,7 +1379,7 @@ void daNPC_TK_c::executeBack() {
                 if (current.pos.y > unkXyz1.y) {
                     cLib_chaseAngleS(&shape_angle.x, 0x2000, 0x400);
                 } else {
-                    cLib_chaseAngleS(&shape_angle.x, 0xffffe000, 0x400);
+                    cLib_chaseAngleS(&shape_angle.x, -8192, 0x400);
                 }
             } else {
                 cLib_chaseAngleS(&field_0x69c, 0x200, 0x10);
@@ -2456,7 +2456,7 @@ void daNPC_TK_c::executeWolfPerch() {
 
 void daNPC_TK_c::executeResistanceDemo() {
     daNpcMoiR_c* npcMoiR;
-    if (fopAcM_SearchByName(PROC_NPC_MOIR, (fopAc_ac_c**)&npcMoiR) == NULL || npcMoiR == NULL) {
+    if (fopAcM_SearchByName(PROC_NPC_MOIR, (fopAc_ac_c**)&npcMoiR) == 0 || npcMoiR == NULL) {
         return;
     }
 
@@ -2623,7 +2623,7 @@ void daNPC_TK_c::executeResistanceDemo() {
     // fallthrough
 
     case 8: {
-        cLib_addCalcAngleS2(&field_0x6a2, 0xffffdc00, 8, 0x200);
+        cLib_addCalcAngleS2(&field_0x6a2, -9216, 8, 0x200);
         cLib_addCalcAngleS2(&field_0x6a0, 0x1000, 8, 0x200);
         cLib_addCalcAngleS2(&field_0x6aa, 0x2000, 8, 0x200);
 
diff --git a/src/d/actor/d_a_npc_tkj2.cpp b/src/d/actor/d_a_npc_tkj2.cpp
index 103a9d57f2..d364c06cc1 100644
--- a/src/d/actor/d_a_npc_tkj2.cpp
+++ b/src/d/actor/d_a_npc_tkj2.cpp
@@ -176,7 +176,7 @@ static void Wind_effect(npc_tkj2_class* i_this) {
                     if ((s16)(sVar1 - i_this->field_0x5c4) < 0) {
                         cLib_addCalcAngleS(&a_this->shape_angle.z, 0x2000, 0x10, 0x1000, 0);
                     } else {
-                        cLib_addCalcAngleS(&a_this->shape_angle.z, 0xFFFFE000, 2, 0x1000, 0);
+                        cLib_addCalcAngleS(&a_this->shape_angle.z, -8192, 2, 0x1000, 0);
                     }
                 }
 
diff --git a/src/d/actor/d_a_npc_uri.cpp b/src/d/actor/d_a_npc_uri.cpp
index ba04932225..c1fe5f439b 100644
--- a/src/d/actor/d_a_npc_uri.cpp
+++ b/src/d/actor/d_a_npc_uri.cpp
@@ -904,12 +904,12 @@ int daNpc_Uri_c::selectAction() {
 
     switch (mType) {
     case TYPE_1:
-        if (field_0x100d != NULL) {
+        if (field_0x100d != 0) {
             field_0xfc0[0] = &daNpc_Uri_c::sitWait;
         } else {
-            if (field_0x100e != NULL) {
+            if (field_0x100e != 0) {
                 /* T_0007 - Ordon Village - During Uli's pick-up tutorial */
-                if (daNpcT_chkTmpBit(7) && field_0x100f == NULL) {
+                if (daNpcT_chkTmpBit(7) && field_0x100f == 0) {
                     field_0xfc0[0] = &daNpc_Uri_c::walk;
                 } else {
                     field_0xfc0[0] = &daNpc_Uri_c::wait;
@@ -981,7 +981,7 @@ int daNpc_Uri_c::getTutorialCond(cXyz param_1) {
             field_0x1000 = mpHIO->m.field_0xa8 - 100.0f;
             return 5;
         }
-        if (field_0x1009 != NULL) {
+        if (field_0x1009 != 0) {
             return 8;
         }
     }
diff --git a/src/d/actor/d_a_npc_ykw.cpp b/src/d/actor/d_a_npc_ykw.cpp
index 9c2c816d37..25b3df0e8f 100644
--- a/src/d/actor/d_a_npc_ykw.cpp
+++ b/src/d/actor/d_a_npc_ykw.cpp
@@ -462,7 +462,7 @@ int daNpc_ykW_c::createHeapCallBack(fopAc_ac_c* i_this) {
 }
 
 int daNpc_ykW_c::ctrlJointCallBack(J3DJoint* i_joint, int param_1) {
-    if (param_1 == NULL) {
+    if (param_1 == 0) {
         J3DModel* model = j3dSys.getModel();
         daNpc_ykW_c* ykw = (daNpc_ykW_c*)model->getUserArea();
         if (ykw != 0) {
diff --git a/src/d/actor/d_a_obj_avalanche.cpp b/src/d/actor/d_a_obj_avalanche.cpp
index 23b4daf8fa..795b9ff45f 100644
--- a/src/d/actor/d_a_obj_avalanche.cpp
+++ b/src/d/actor/d_a_obj_avalanche.cpp
@@ -253,7 +253,7 @@ int daObjAvalanche_c::demoProc() {
 void daObjAvalanche_c::setEffect() {
     cXyz acStack_18(0.0f, 0.0f, 0.0f);
     csXyz cStack_20(0, 0, 0);
-    dComIfGp_particle_set(0x8c51, &acStack_18, &cStack_20, NULL, 0xff, NULL, 0xffffffff, NULL, NULL,
+    dComIfGp_particle_set(0x8c51, &acStack_18, &cStack_20, NULL, 0xff, NULL, -1, NULL, NULL,
                           NULL);
 }
 
diff --git a/src/d/actor/d_a_obj_magne_arm.cpp b/src/d/actor/d_a_obj_magne_arm.cpp
index e2531f8d34..049323dace 100644
--- a/src/d/actor/d_a_obj_magne_arm.cpp
+++ b/src/d/actor/d_a_obj_magne_arm.cpp
@@ -186,8 +186,8 @@ int daObjMarm_c::Create() {
         mIsYRotForward = 0;
     }
 
-    if (dComIfG_Bgsp().Regist((dBgW_Base*)mpBgW1, this) != NULL ||
-        dComIfG_Bgsp().Regist((dBgW_Base*)mpBgW2, this) != NULL)
+    if (dComIfG_Bgsp().Regist((dBgW_Base*)mpBgW1, this) != false ||
+        dComIfG_Bgsp().Regist((dBgW_Base*)mpBgW2, this) != false)
     {
         return FALSE;
     }
@@ -1060,11 +1060,11 @@ void daObjMarm_c::debugDraw() {
 }
 
 int daObjMarm_c::Delete() {
-    if (mpBgW1 != NULL && mpBgW1->ChkUsed() != NULL) {
+    if (mpBgW1 != NULL && mpBgW1->ChkUsed() != false) {
         dComIfG_Bgsp().Release(mpBgW1);
     }
 
-    if (mpBgW2 != NULL && mpBgW2->ChkUsed() != NULL) {
+    if (mpBgW2 != NULL && mpBgW2->ChkUsed() != false) {
         dComIfG_Bgsp().Release(mpBgW2);
     }
     endMagneHoleEffect();
diff --git a/src/d/d_bg_s.cpp b/src/d/d_bg_s.cpp
index 190e2badc9..7295126a6b 100644
--- a/src/d/d_bg_s.cpp
+++ b/src/d/d_bg_s.cpp
@@ -712,7 +712,7 @@ void dBgS::MoveBgMatrixCrrPos(cBgS_PolyInfo const& i_poly, bool param_1, cXyz* i
 void dBgS_MoveBGProc_Typical(dBgW* i_bgw, void* i_actor_ptr, cBgS_PolyInfo const& i_poly,
                              bool param_3, cXyz* i_pos, csXyz* i_angle, csXyz* i_shapeAngle) {
     Mtx m;
-    if (i_bgw->GetOldInvMtx(m) != NULL) {
+    if (i_bgw->GetOldInvMtx(m) != 0) {
         cXyz move_old;
         MTXMultVec(m, i_pos, &move_old);
 
diff --git a/src/d/d_camera.cpp b/src/d/d_camera.cpp
index 8ce17ecc83..d724fb65ed 100644
--- a/src/d/d_camera.cpp
+++ b/src/d/d_camera.cpp
@@ -10131,7 +10131,7 @@ bool dCamera_c::eventCamera(s32 param_0) {
         }
 
         int* sp90_i;
-        if (getEvStringData(sp90, "Trim", "DEFAULT") != NULL) {
+        if (getEvStringData(sp90, "Trim", "DEFAULT") != false) {
             sp90_i = (int*)sp90;
             if (*sp90_i == 'STAN') {
                 mEventData.field_0x1c = 0;
diff --git a/src/d/d_ev_camera.cpp b/src/d/d_ev_camera.cpp
index aef250cae0..444a9be213 100644
--- a/src/d/d_ev_camera.cpp
+++ b/src/d/d_ev_camera.cpp
@@ -3134,7 +3134,7 @@ bool dCamera_c::useItem1EvCamera() {
 
             if (item_p->field_0x20 < item_p->field_0x4) break;
 
-            if (data_list[item_p->mType][1].field_0x08 != NULL && item_p->field_0x1c == 0) {
+            if (data_list[item_p->mType][1].field_0x08 != 0 && item_p->field_0x1c == 0) {
                 item_p->field_0x1c = 1;
                 item_p->field_0x0 = 1;
                 break;
diff --git a/src/d/d_kankyo_rain.cpp b/src/d/d_kankyo_rain.cpp
index 73e9af07cc..fce7f79a71 100644
--- a/src/d/d_kankyo_rain.cpp
+++ b/src/d/d_kankyo_rain.cpp
@@ -2540,9 +2540,9 @@ void dKyr_drawSun(Mtx drawMtx, cXyz* ppos, GXColor& unused, u8** tex) {
                 color_reg0.b = 0;
 
                 f32 size = 8000.0f;
-                if (strcmp(dComIfGp_getStartStageName(), "F_SP127") == NULL) {
+                if (strcmp(dComIfGp_getStartStageName(), "F_SP127") == 0) {
                     size = 11000.0f;
-                } else if (strcmp(dComIfGp_getStartStageName(), "F_SP200") == NULL) {
+                } else if (strcmp(dComIfGp_getStartStageName(), "F_SP200") == 0) {
                     size = 10000.0f;
                 }
 
diff --git a/src/d/d_menu_item_explain.cpp b/src/d/d_menu_item_explain.cpp
index a6cb9a456a..7119ef3e03 100644
--- a/src/d/d_menu_item_explain.cpp
+++ b/src/d/d_menu_item_explain.cpp
@@ -290,7 +290,7 @@ void dMenu_ItemExplain_c::move() {
     if (status != mStatus) {
         (this->*init_process[mStatus])();
     }
-    if (mStatus != NULL) {
+    if (mStatus != 0) {
         mpInfoScreen->animation();
     }
     if (g_ringHIO.mItemDescAlpha != mDescAlpha) {
diff --git a/src/d/d_menu_option.cpp b/src/d/d_menu_option.cpp
index ac3dbd949b..cc34f26938 100644
--- a/src/d/d_menu_option.cpp
+++ b/src/d/d_menu_option.cpp
@@ -1484,12 +1484,12 @@ void dMenu_Option_c::screenSet() {
         }
     }
     for (int i = 0; i < 6; i++) {
-        if (let2_n[i] != NULL) {
+        if (let2_n[i] != 0) {
             mpMenuPane3[i] = new CPaneMgr(mpClipScreen, let2_n[i], 0, NULL);
         } else {
             mpMenuPane3[i] = NULL;
         }
-        if (menu3_n[i] != NULL) {
+        if (menu3_n[i] != 0) {
             mpMenuPane32[i] = new CPaneMgr(mpClipScreen, menu3_n[i], 0, NULL);
         } else {
             mpMenuPane32[i] = NULL;
@@ -1720,7 +1720,7 @@ void dMenu_Option_c::screenSet() {
         field_0x1c0[i] = 0;
     }
     for (int i = 0; i < 3; i++) {
-        if (z_tx[i] != NULL) {
+        if (z_tx[i] != 0) {
             mpZButtonText[i] = new CPaneMgr(mpBackScreen, z_tx[i], 2, NULL);
         } else {
             mpZButtonText[i] = NULL;
diff --git a/src/d/d_particle.cpp b/src/d/d_particle.cpp
index 002323e476..0a169d2546 100644
--- a/src/d/d_particle.cpp
+++ b/src/d/d_particle.cpp
@@ -1602,7 +1602,7 @@ s32 dPa_control_c::getPolyColor(cBgS_PolyInfo& param_0, int param_1, _GXColor* p
         return 0;
     }
 
-    if (param_1 == NULL) {
+    if (param_1 == 0) {
         dKy_pol_eff_prim_get(&param_0, param_2);
         dKy_pol_eff_env_get(&param_0, param_3);
         *param_4 = dKy_pol_eff_alpha_get(&param_0);
diff --git a/src/d/d_resorce.cpp b/src/d/d_resorce.cpp
index fe2b2e37ef..40c94e7e51 100644
--- a/src/d/d_resorce.cpp
+++ b/src/d/d_resorce.cpp
@@ -54,7 +54,7 @@ int dRes_info_c::set(char const* i_arcName, char const* i_path, u8 i_mountDirect
     JUT_ASSERT(120, strlen(i_arcName) <= NAME_MAX);
 #endif
 
-    if (*i_path != NULL) {
+    if (*i_path != '\0') {
         char path[40];
         snprintf(path, sizeof(path), "%s%s.arc", i_path, i_arcName);
         mDMCommand = mDoDvdThd_mountArchive_c::create(path, i_mountDirection, i_heap);
diff --git a/src/d/d_s_play.cpp b/src/d/d_s_play.cpp
index 69512ffea2..1e4636c457 100644
--- a/src/d/d_s_play.cpp
+++ b/src/d/d_s_play.cpp
@@ -554,7 +554,7 @@ static int phase_3(dScnPly_c* i_this) {
         return cPhs_INIT_e;
     }
 
-    if (!i_this->field_0x1d0 == NULL && !i_this->field_0x1d0->sync()) {
+    if (i_this->field_0x1d0 != NULL && !i_this->field_0x1d0->sync()) {
         return cPhs_INIT_e;
     }
 
diff --git a/src/d/d_s_room.cpp b/src/d/d_s_room.cpp
index 1adb5a43f1..cf3bb7c93b 100644
--- a/src/d/d_s_room.cpp
+++ b/src/d/d_s_room.cpp
@@ -329,7 +329,7 @@ static int phase_1(room_of_scene_class* i_this) {
         } else {
             stage_stag_info_class* stagInfo = dComIfGp_getStage()->getStagInfo();
 
-            if (dStage_staginfo_GetArchiveHeap(stagInfo) != NULL) {
+            if (dStage_staginfo_GetArchiveHeap(stagInfo) != FALSE) {
                 heap = mDoExt_getArchiveHeap();
             }
         }
diff --git a/src/d/d_stage.cpp b/src/d/d_stage.cpp
index 4fdbd71a44..cd0fcd0958 100644
--- a/src/d/d_stage.cpp
+++ b/src/d/d_stage.cpp
@@ -2725,7 +2725,7 @@ void dStage_Delete() {
     OS_REPORT("dStage_Delete\n");
 
     char* demoArcName = dStage_roomControl_c::getDemoArcName();
-    if (*demoArcName != NULL) {
+    if (*demoArcName != '\0') {
         dComIfG_deleteObjectResMain(demoArcName);
     }
 
diff --git a/src/m_Do/m_Do_ext.cpp b/src/m_Do/m_Do_ext.cpp
index a71ed9a42c..cb9dc7fb80 100644
--- a/src/m_Do/m_Do_ext.cpp
+++ b/src/m_Do/m_Do_ext.cpp
@@ -3713,7 +3713,7 @@ J3DModel* mDoExt_J3DModel__create(J3DModelData* i_modelData, u32 i_modelFlag, u3
             bool hasSharedDlistObj =
                 i_modelData->getMaterialNodePointer(0)->getSharedDisplayListObj() != NULL;
             // Update the modelFlag if the model data passed in has a shared dlist object
-            if (hasSharedDlistObj != NULL) {
+            if (hasSharedDlistObj != false) {
                 if (i_modelData->isLocked()) {
                     i_modelFlag = J3DMdlFlag_UseSharedDL;
                 } else if (i_modelFlag == J3DMdlFlag_UseSharedDL) {