diff --git a/src/Block.c b/src/Block.c
index e4b06ef42..798947e3b 100644
--- a/src/Block.c
+++ b/src/Block.c
@@ -192,16 +192,15 @@ void Block_SetCollide(BlockID block, cc_uint8 collide) {
 }
 
 void Block_SetDrawType(BlockID block, cc_uint8 draw) {
-	Vec3 zero = Vec3_Zero();
-	Vec3 one  = Vec3_One();
-
 	if (draw == DRAW_OPAQUE && Blocks.Collide[block] != COLLIDE_SOLID) draw = DRAW_TRANSPARENT;
 	Blocks.Draw[block] = draw;
 	Block_RecalcIsLiquid(block);
 
+	/* Whether a block is opaque and exactly occupies a cell in the world */
+	/* The mesh builder module needs this information for optimisation purposes */
 	Blocks.FullOpaque[block] = draw == DRAW_OPAQUE
-		&& Vec3_Equals(&Blocks.MinBB[block], &zero)
-		&& Vec3_Equals(&Blocks.MaxBB[block], &one);
+		&& Blocks.MinBB[block].X == 0 && Blocks.MinBB[block].Y == 0 && Blocks.MinBB[block].Z == 0
+		&& Blocks.MaxBB[block].X == 1 && Blocks.MaxBB[block].Y == 1 && Blocks.MaxBB[block].Z == 1;
 }
 
 
@@ -244,12 +243,11 @@ void Block_ResetProps(BlockID block) {
 
 	Blocks.Draw[block] = DefaultSet_Draw(block);
 	if (Blocks.Draw[block] == DRAW_SPRITE) {
-		Blocks.MinBB[block] = Vec3_Create3(2.50f/16.0f, 0.0f, 2.50f/16.0f);
-		Blocks.MaxBB[block] = Vec3_Create3(13.5f/16.0f, 1.0f, 13.5f/16.0f);
+		Vec3_Set(Blocks.MinBB[block], 2.50f/16.0f, 0, 2.50f/16.0f);
+		Vec3_Set(Blocks.MaxBB[block], 13.5f/16.0f, 1, 13.5f/16.0f);
 	} else {		
-		Blocks.MinBB[block] = Vec3_Zero();
-		Blocks.MaxBB[block] = Vec3_One();
-		Blocks.MaxBB[block].Y = DefaultSet_Height(block);
+		Vec3_Set(Blocks.MinBB[block], 0, 0,                        0);
+		Vec3_Set(Blocks.MaxBB[block], 1, DefaultSet_Height(block), 1);
 	}
 
 	Block_SetDrawType(block, Blocks.Draw[block]);
diff --git a/src/Entity.c b/src/Entity.c
index 87b6178a4..a8625e381 100644
--- a/src/Entity.c
+++ b/src/Entity.c
@@ -68,7 +68,7 @@ static PackedCol Entity_GetCol(struct Entity* e) {
 
 void Entity_Init(struct Entity* e) {
 	static const String model = String_FromConst("humanoid");
-	e->ModelScale = Vec3_Create1(1.0f);
+	Vec3_Set(e->ModelScale, 1,1,1);
 	e->uScale   = 1.0f;
 	e->vScale   = 1.0f;
 	e->StepSize = 0.5f;
@@ -118,7 +118,7 @@ static void Entity_ParseScale(struct Entity* e, const String* scale) {
 	/* local player doesn't allow giant model scales */
 	/* (can't climb stairs, extremely CPU intensive collisions) */
 	if (e->ModelRestrictedScale) { value = min(value, e->Model->MaxScale); }
-	e->ModelScale = Vec3_Create1(value);
+	Vec3_Set(e->ModelScale, value,value,value);
 }
 
 static void Entity_SetBlockModel(struct Entity* e, const String* model) {
@@ -136,13 +136,13 @@ static void Entity_SetBlockModel(struct Entity* e, const String* model) {
 
 void Entity_SetModel(struct Entity* e, const String* model) {
 	String name, scale, skin;
-	e->ModelScale = Vec3_Create1(1.0f);
+	Vec3_Set(e->ModelScale, 1,1,1);
 	String_UNSAFE_Separate(model, '|', &name, &scale);
 
 	/* 'giant' model kept for backwards compatibility */
 	if (String_CaselessEqualsConst(&name, "giant")) {
 		name = String_FromReadonly("humanoid");
-		e->ModelScale = Vec3_Create1(2.0f);
+		Vec3_Set(e->ModelScale, 2,2,2);
 	}
 
 	e->ModelBlock   = BLOCK_AIR;
@@ -796,7 +796,10 @@ static void LocalPlayer_HandleInput(float* xMoving, float* zMoving) {
 		hacks->FlyingDown   = KeyBind_IsPressed(KEYBIND_FLY_DOWN);
 
 		if (hacks->WOMStyleHacks && hacks->Enabled && hacks->CanNoclip) {
-			if (hacks->Noclip) p->Base.Velocity = Vec3_Zero();
+			if (hacks->Noclip) {
+				/* need the { } because it's a macro */
+				Vec3_Set(p->Base.Velocity, 0,0,0);
+			}
 			hacks->Noclip = KeyBind_IsPressed(KEYBIND_NOCLIP);
 		}
 	}
@@ -826,7 +829,7 @@ static void LocalPlayer_Tick(struct Entity* e, double delta) {
 
 	/* Immediate stop in noclip mode */
 	if (!hacks->NoclipSlide && (hacks->Noclip && xMoving == 0 && zMoving == 0)) {
-		e->Velocity = Vec3_Zero();
+		Vec3_Set(e->Velocity, 0,0,0);
 	}
 
 	PhysicsComp_UpdateVelocityState(&p->Physics);
@@ -906,7 +909,7 @@ static void LocalPlayer_Init(void) {
 static void LocalPlayer_Reset(void) {
 	struct LocalPlayer* p = &LocalPlayer_Instance;
 	p->ReachDistance = 5.0f;
-	p->Base.Velocity = Vec3_Zero();
+	Vec3_Set(p->Base.Velocity, 0,0,0);
 	p->Physics.JumpVel       = 0.42f;
 	p->Physics.ServerJumpVel = 0.42f;
 	/* p->Base.Health = 20; TODO: survival mode stuff */
@@ -914,8 +917,8 @@ static void LocalPlayer_Reset(void) {
 
 static void LocalPlayer_OnNewMap(void) {
 	struct LocalPlayer* p = &LocalPlayer_Instance;
-	p->Base.Velocity = Vec3_Zero();
-	p->OldVelocity   = Vec3_Zero();
+	Vec3_Set(p->Base.Velocity, 0,0,0);
+	Vec3_Set(p->OldVelocity,   0,0,0);
 
 	p->_warnedRespawn = false;
 	p->_warnedFly     = false;
@@ -956,7 +959,7 @@ static void LocalPlayer_DoRespawn(void) {
 	spawn.Y += 2.0f/16.0f;
 	LocationUpdate_MakePosAndOri(&update, spawn, p->SpawnRotY, p->SpawnHeadX, false);
 	p->Base.VTABLE->SetLocation(&p->Base, &update, false);
-	p->Base.Velocity = Vec3_Zero();
+	Vec3_Set(p->Base.Velocity, 0,0,0);
 
 	/* Update onGround, otherwise if 'respawn' then 'space' is pressed, you still jump into the air if onGround was true before */
 	Entity_GetBounds(&p->Base, &bb);
diff --git a/src/EntityComponents.c b/src/EntityComponents.c
index 4a554ac73..e52449aa1 100644
--- a/src/EntityComponents.c
+++ b/src/EntityComponents.c
@@ -874,10 +874,9 @@ static void Collisions_CollideWithReachableBlocks(struct CollisionsComp* comp, i
 void Collisions_MoveAndWallSlide(struct CollisionsComp* comp) {
 	struct Entity* e = comp->Entity;
 	struct AABB entityBB, entityExtentBB;
-	Vec3 zero = Vec3_Zero();
 	int count;
 
-	if (Vec3_Equals(&e->Velocity, &zero)) return;
+	if (Vec3_IsZero(e->Velocity)) return;
 	count = Searcher_FindReachableBlocks(e,            &entityBB, &entityExtentBB);
 	Collisions_CollideWithReachableBlocks(comp, count, &entityBB, &entityExtentBB);
 }
diff --git a/src/EnvRenderer.c b/src/EnvRenderer.c
index 00fdad3da..73aa4edad 100644
--- a/src/EnvRenderer.c
+++ b/src/EnvRenderer.c
@@ -308,7 +308,7 @@ void EnvRenderer_RenderSkybox(double deltaTime) {
 
 	/* Rotate around camera */
 	pos = Camera.CurrentPos;
-	Camera.CurrentPos = Vec3_Zero();
+	Vec3_Set(Camera.CurrentPos, 0,0,0);
 	Camera.Active->GetView(&view); Matrix_MulBy(&m, &view);
 	Camera.CurrentPos = pos;
 
diff --git a/src/HeldBlockRenderer.c b/src/HeldBlockRenderer.c
index 96a33195f..720231072 100644
--- a/src/HeldBlockRenderer.c
+++ b/src/HeldBlockRenderer.c
@@ -30,14 +30,14 @@ static void HeldBlockRenderer_RenderModel(void) {
 	
 	if (Blocks.Draw[held_block] == DRAW_GAS) {
 		model = LocalPlayer_Instance.Base.Model;
-		held_entity.ModelScale = Vec3_Create1(1.0f);
+		Vec3_Set(held_entity.ModelScale, 1.0f,1.0f,1.0f);
 
 		Gfx_SetAlphaTest(true);
 		Model_RenderArm(model, &held_entity);
 		Gfx_SetAlphaTest(false);
 	} else {	
 		model = Model_Get(&block);
-		held_entity.ModelScale = Vec3_Create1(0.4f);
+		Vec3_Set(held_entity.ModelScale, 0.4f,0.4f,0.4f);
 
 		Gfx_SetupAlphaState(Blocks.Draw[held_block]);
 		Model_Render(model, &held_entity);
diff --git a/src/Input.h b/src/Input.h
index c35bc9430..280e958bd 100644
--- a/src/Input.h
+++ b/src/Input.h
@@ -70,7 +70,6 @@ void Input_SetPressed(Key key, cc_bool pressed);
 /* Resets all keyboard keys to released state. */
 /* Raises InputEvents.Up for each previously pressed key. */
 void Key_Clear(void);
-typedef int MouseButton;
 
 /* Whether raw mouse/touch input is being listened for. */
 extern cc_bool Input_RawMode;
diff --git a/src/LScreens.c b/src/LScreens.c
index f72eb7133..7ed80014e 100644
--- a/src/LScreens.c
+++ b/src/LScreens.c
@@ -117,7 +117,7 @@ static void LScreen_KeyPress(struct LScreen* s, char key) {
 	s->selectedWidget->VTABLE->KeyPress(s->selectedWidget, key);
 }
 
-static void LScreen_MouseDown(struct LScreen* s, MouseButton btn) {
+static void LScreen_MouseDown(struct LScreen* s, int btn) {
 	struct LWidget* over = LScreen_WidgetAt(s, Mouse_X, Mouse_Y);
 	struct LWidget* prev = s->selectedWidget;
 
@@ -125,7 +125,7 @@ static void LScreen_MouseDown(struct LScreen* s, MouseButton btn) {
 	if (over) LScreen_SelectWidget(s, over, over == prev);
 }
 
-static void LScreen_MouseUp(struct LScreen* s, MouseButton btn) {
+static void LScreen_MouseUp(struct LScreen* s, int btn) {
 	struct LWidget* over = LScreen_WidgetAt(s, Mouse_X, Mouse_Y);
 	struct LWidget* prev = s->selectedWidget;
 
@@ -1274,7 +1274,7 @@ static void ServersScreen_KeyDown(struct LScreen* s_, Key key, cc_bool was) {
 	}
 }
 
-static void ServersScreen_MouseUp(struct LScreen* s_, MouseButton btn) {
+static void ServersScreen_MouseUp(struct LScreen* s_, int btn) {
 	struct ServersScreen* s = (struct ServersScreen*)s_;
 	s->table.VTABLE->OnUnselect(&s->table);
 	LScreen_MouseUp(s_, btn);
diff --git a/src/LScreens.h b/src/LScreens.h
index 3f29eaae3..d41510db7 100644
--- a/src/LScreens.h
+++ b/src/LScreens.h
@@ -19,8 +19,8 @@ typedef void (*LWidget_Func)(struct LScreen* s, struct LWidget* w);
 	LScreen_Func OnDisplay; /* Called when framebuffer is about to be displayed. */ \
 	void (*KeyDown)(struct LScreen* s,    Key key, cc_bool wasDown); \
 	void (*KeyPress)(struct LScreen* s,   char c);  \
-	void (*MouseDown)(struct LScreen* s,  MouseButton btn); \
-	void (*MouseUp)(struct LScreen* s,    MouseButton btn); \
+	void (*MouseDown)(struct LScreen* s,  int btn); \
+	void (*MouseUp)(struct LScreen* s,    int btn); \
 	void (*MouseMove)(struct LScreen* s,  int deltaX, int deltaY); \
 	void (*MouseWheel)(struct LScreen* s, float delta); \
 	LWidget_Func HoverWidget;    /* Called when mouse is moved over a given widget. */ \
diff --git a/src/Model.c b/src/Model.c
index 33370e064..82cf3eb60 100644
--- a/src/Model.c
+++ b/src/Model.c
@@ -39,9 +39,9 @@ void Model_Init(struct Model* model) {
 	model->UsesHumanSkin  = false;
 	model->Pushes = true;
 
-	model->Gravity        = 0.08f;
-	model->Drag           = Vec3_Create3(0.91f, 0.98f, 0.91f);
-	model->GroundFriction = Vec3_Create3(0.6f, 1.0f, 0.6f);
+	model->Gravity     = 0.08f;
+	Vec3_Set(model->Drag,           0.91f, 0.98f, 0.91f);
+	Vec3_Set(model->GroundFriction, 0.6f,   1.0f,  0.6f);
 
 	model->MaxScale    = 2.0f;
 	model->ShadowScale = 1.0f;
diff --git a/src/Particle.c b/src/Particle.c
index 9af644c5b..2d073ad50 100644
--- a/src/Particle.c
+++ b/src/Particle.c
@@ -73,8 +73,10 @@ static cc_bool Particle_TestY(struct Particle* p, int y, cc_bool topFace, cc_boo
 	cc_bool collideVer;
 
 	if (y < 0) {
-		p->nextPos.Y = ENTITY_ADJUSTMENT; p->lastPos.Y = ENTITY_ADJUSTMENT;
-		p->velocity  = Vec3_Zero();
+		p->nextPos.Y = ENTITY_ADJUSTMENT; 
+		p->lastPos.Y = ENTITY_ADJUSTMENT;
+
+		Vec3_Set(p->velocity, 0,0,0);
 		particle_hitTerrain = true;
 		return false;
 	}
@@ -90,7 +92,8 @@ static cc_bool Particle_TestY(struct Particle* p, int y, cc_bool topFace, cc_boo
 		float adjust = topFace ? ENTITY_ADJUSTMENT : -ENTITY_ADJUSTMENT;
 		p->lastPos.Y = collideY + adjust;
 		p->nextPos.Y = p->lastPos.Y;
-		p->velocity  = Vec3_Zero();
+
+		Vec3_Set(p->velocity, 0,0,0);
 		particle_hitTerrain = true;
 		return false;
 	}
diff --git a/src/Vectors.h b/src/Vectors.h
index 3f6f06eb7..105917256 100644
--- a/src/Vectors.h
+++ b/src/Vectors.h
@@ -21,14 +21,6 @@ struct Matrix { struct Vec4 Row0, Row1, Row2, Row3; };
 /* Identity matrix. (A * Identity = A) */
 extern const struct Matrix Matrix_Identity;
 
-/* Returns a vector with all components 0. */
-static CC_INLINE Vec3 Vec3_Zero(void) {
-	Vec3 v = { 0, 0, 0 }; return v;
-}
-/* Returns a vector with all components 1. */
-static CC_INLINE Vec3 Vec3_One(void) {
-	Vec3 v = { 1, 1, 1 }; return v;
-}
 /* Returns a vector with all components set to Int32_MaxValue. */
 static CC_INLINE IVec3 IVec3_MaxValue(void) {
 	IVec3 v = { Int32_MaxValue, Int32_MaxValue, Int32_MaxValue }; return v;
@@ -37,13 +29,15 @@ static CC_INLINE Vec3 Vec3_BigPos(void) {
 	Vec3 v = { 1e25f, 1e25f, 1e25f }; return v;
 }
 
-static CC_INLINE Vec3 Vec3_Create1(float value) {
-	Vec3 v; v.X = value; v.Y = value; v.Z = value; return v;
-}
 static CC_INLINE Vec3 Vec3_Create3(float x, float y, float z) {
 	Vec3 v; v.X = x; v.Y = y; v.Z = z; return v;
 }
 
+/* Sets the X, Y, and Z components of a 3D vector */
+#define Vec3_Set(v, x, y, z) (v).X = x; (v).Y = y; (v).Z = z;
+/* Whether all components of a 3D vector are 0 */
+#define Vec3_IsZero(v) ((v).X == 0 && (v).Y == 0 && (v).Z == 0)
+
 /* Returns the squared length of the vector. */
 /* Squared length can be used for comparison, to avoid a costly sqrt() */
 /* However, you must sqrt() this when adding lengths. */