diff --git a/th01/math/subpixel.hpp b/th01/math/subpixel.hpp
index 468a3987..d4864469 100644
--- a/th01/math/subpixel.hpp
+++ b/th01/math/subpixel.hpp
@@ -5,6 +5,7 @@
 
 #define PIXEL_NONE (-999)
 
+typedef uint8_t subpixel_length_8_t;
 typedef int subpixel_t;
 
 static const subpixel_t SUBPIXEL_FACTOR = 16;
@@ -24,8 +25,8 @@ inline subpixel_t to_sp(float pixel_v) {
 	return static_cast<subpixel_t>(pixel_v * SUBPIXEL_FACTOR);
 }
 
-inline unsigned char to_sp8(float pixel_v) {
-	return static_cast<unsigned char>(to_sp(pixel_v));
+inline subpixel_length_8_t to_sp8(float pixel_v) {
+	return static_cast<subpixel_length_8_t>(to_sp(pixel_v));
 }
 
 template <class SubpixelType, class PixelType> class SubpixelBase {
@@ -100,6 +101,6 @@ struct SPPoint : public SPPointBase<Subpixel> {
 };
 
 // 8-bit (Q4.4)
-typedef SubpixelBase<unsigned char, unsigned char> SubpixelLength8;
+typedef SubpixelBase<subpixel_length_8_t, subpixel_length_8_t> SubpixelLength8;
 typedef SubpixelBase<char, char> Subpixel8;
 typedef SPPointBase<Subpixel8> SPPoint8;
diff --git a/th04/main/bullet/add.cpp b/th04/main/bullet/add.cpp
index 11b96598..29554260 100644
--- a/th04/main/bullet/add.cpp
+++ b/th04/main/bullet/add.cpp
@@ -21,7 +21,7 @@ void near tune_for_easy(void)
 	switch(tmpl.group) {
 	case BG_STACK:
 	case BG_STACK_AIMED:
-		tmpl.delta.stack_speed -= (tmpl.delta.stack_speed / 4);
+		tmpl.delta.stack_speed.v -= (tmpl.delta.stack_speed.v / 4);
 		if(tmpl.count >= 2) {
 			tmpl.count--;
 		}
@@ -48,17 +48,17 @@ void near tune_for_hard(void)
 	case BG_SINGLE_AIMED:
 		tmpl.group = BG_STACK_AIMED;
 		tmpl.count = 2;
-		tmpl.delta.stack_speed = to_sp(0.375f);
+		tmpl.delta.stack_speed.set(0.375f);
 		break;
 	case BG_SINGLE:
 		tmpl.group = BG_STACK;
 		tmpl.count = 2;
-		tmpl.delta.stack_speed = to_sp(0.375f);
+		tmpl.delta.stack_speed.set(0.375f);
 		break;
 
 	case BG_STACK:
 	case BG_STACK_AIMED:
-		tmpl.delta.stack_speed += (tmpl.delta.stack_speed / 2);
+		tmpl.delta.stack_speed.v += (tmpl.delta.stack_speed.v / 2);
 		break;
 
 	case BG_SPREAD:
@@ -98,7 +98,7 @@ void near tune_for_lunatic(void)
 
 	case BG_STACK:
 	case BG_STACK_AIMED:
-		tmpl.delta.stack_speed += (tmpl.delta.stack_speed / 2);
+		tmpl.delta.stack_speed.v += (tmpl.delta.stack_speed.v / 2);
 		tmpl.count++;
 		break;
 
@@ -188,7 +188,7 @@ void pascal near bullet_template_tune_lunatic(void)
 
 void pascal near bullets_add_regular_easy(void)
 {
-	unsigned char speed;
+	subpixel_length_8_t speed;
 	unsigned char count;
 
 	if(bullet_zap.active) {
@@ -202,7 +202,7 @@ void pascal near bullets_add_regular_easy(void)
 }
 
 inline void keep_speed_from_being_mutated_when_calling(nearfunc_t_near func) {
-	unsigned char speed = bullet_template.speed.v;
+	subpixel_length_8_t speed = bullet_template.speed.v;
 	func();
 	bullet_template.speed.v = speed;
 }
@@ -274,7 +274,7 @@ void near bullets_add_special_fixedspeed(void)
 bool16 pascal near bullet_velocity_and_angle_set(int group_i)
 {
 	int angle = 0x00;
-	unsigned char speed;
+	subpixel_length_8_t speed;
 	bool done;
 
 	// Due to this default, invalid group values lead to the spawn functions
@@ -550,7 +550,7 @@ void pascal near bullets_add_regular_raw(void)
 			bullet->flag = 1;
 			bullet->move_state = static_cast<bullet_move_state_t>(move_state);
 			bullet->ax.slowdown_time = BMS_SLOWDOWN_FRAMES;
-			bullet->dx.slowdown_speed_delta = (
+			bullet->dx.slowdown_speed_delta.v = (
 				to_sp8(BMS_SLOWDOWN_BASE_SPEED) - bullet_template.speed
 			);
 			bullet_init_from_template(bullet, group_done, group_i, spawn_state);
diff --git a/th04/main/bullet/bullet.hpp b/th04/main/bullet/bullet.hpp
index 93f48316..1659295a 100644
--- a/th04/main/bullet/bullet.hpp
+++ b/th04/main/bullet/bullet.hpp
@@ -138,8 +138,8 @@ struct bullet_t {
 	union {
 		// Difference between [speed_final] and the BMS_SLOWDOWN_BASE_SPEED.
 		// Always positive for BMS_SLOWDOWN bullets.
-		unsigned char slowdown_speed_delta;	// with BMS_SLOWDOWN
-		bullet_special_angle_t angle;      	// with BMS_SPECIAL
+		SubpixelLength8 slowdown_speed_delta;	// with BMS_SLOWDOWN
+		bullet_special_angle_t angle;        	// with BMS_SPECIAL
 	} dx;
 	int patnum;
 
diff --git a/th04/main/bullet/types.h b/th04/main/bullet/types.h
index 69a426ae..4c36e64e 100644
--- a/th04/main/bullet/types.h
+++ b/th04/main/bullet/types.h
@@ -1,8 +1,6 @@
 typedef union {
 	unsigned char spread_angle;
-	// In subpixels, obviously, but pre-C++11 doesn't let us use any of the
-	// Subpixel classes with their custom assignment operators in a union...
-	unsigned char stack_speed;
+	SubpixelLength8 stack_speed;
 } bullet_template_delta_t;
 
 // All _AIMED groups define the 0° [angle] as the current player position,
diff --git a/th04/main/bullet/update.cpp b/th04/main/bullet/update.cpp
index a71611d8..381fa418 100644
--- a/th04/main/bullet/update.cpp
+++ b/th04/main/bullet/update.cpp
@@ -309,7 +309,7 @@ void bullets_update(void)
 			} else if(bullet->move_state == BMS_SLOWDOWN) {
 				bullet->ax.slowdown_time--;
 				bullet->speed_cur.v = (bullet->speed_final.v + ((
-					bullet->ax.slowdown_time * bullet->dx.slowdown_speed_delta
+					bullet->ax.slowdown_time * bullet->dx.slowdown_speed_delta.v
 				) / BMS_SLOWDOWN_FRAMES));
 				if(bullet->ax.slowdown_time == 0) {
 					bullet->speed_cur = bullet->speed_final;
diff --git a/th05/main/bullet/clip.cpp b/th05/main/bullet/clip.cpp
index 27afd343..9e184e51 100644
--- a/th05/main/bullet/clip.cpp
+++ b/th05/main/bullet/clip.cpp
@@ -50,7 +50,7 @@ clipped:
 	}
 
 	if(!group_fixedspeed) {
-		bullet_template.speed = playperf_speedtune(bullet_template.speed);
+		bullet_template.speed.v = playperf_speedtune(bullet_template.speed.v);
 	}
 	return false;
 }
diff --git a/th05/main/playperf.hpp b/th05/main/playperf.hpp
index 701b10d3..dbfc33f1 100644
--- a/th05/main/playperf.hpp
+++ b/th05/main/playperf.hpp
@@ -1,4 +1,6 @@
 #include "th04/main/playperf.hpp"
 
 // Returns [speed] tuned based on [playperf].
-SubpixelLength8 __fastcall near playperf_speedtune(unsigned char speed);
+subpixel_length_8_t __fastcall near playperf_speedtune(
+	subpixel_length_8_t speed
+);