Slow down bots on straightaways (reinventing the accel wheel)

src/d_player.h

@@ -430,6 +430,7 @@ struct botvars_t
 	tic_t rouletteTimeout; // If it takes too long to decide, try lowering priority until we find something valid.
 
 	angle_t predictionError; // How bad is our momentum angle relative to where we're trying to go?
+	INT16 straightawayTime; // How long have we been going straight? (See k_bot.h)
 };
 
 // player_t struct for round-specific condition tracking

src/k_bot.cpp

@@ -823,6 +823,7 @@ fixed_t K_BotRubberband(const player_t *player)
 fixed_t K_UpdateRubberband(player_t *player)
 {
 	fixed_t dest = K_BotRubberband(player);
+	dest = (player->botvars.straightawayTime > 0) ? FixedMul(BOTSTRAIGHTSTRENGTH, dest) : dest;
 	fixed_t ret = player->botvars.rubberband;
 
 	UINT8 ease_soften = 8;
@@ -2123,6 +2124,14 @@ void K_UpdateBotGameplayVars(player_t *player)
 		}
 	}
 
+	if (player->botvars.predictionError <= BOTSTRAIGHTANGLE)
+		player->botvars.straightawayTime++;
+	else
+		player->botvars.straightawayTime -= 5;
+
+	player->botvars.straightawayTime = std::min<INT16>(player->botvars.straightawayTime, BOTSTRAIGHTTIME);
+	player->botvars.straightawayTime = std::max<INT16>(player->botvars.straightawayTime, -1 * BOTSTRAIGHTTIME);
+
 	const botcontroller_t *botController = K_GetBotController(player->mo);
 	if (K_TryRingShooter(player, botController) == true)
 	{

src/k_bot.h

@@ -46,6 +46,10 @@ extern "C" {
 // How long it takes for a Lv.1 bot to decide to pick an item.
 #define BOT_ITEM_DECISION_TIME (2*TICRATE)
 
+#define BOTSTRAIGHTTIME (TICRATE/2)
+#define BOTSTRAIGHTSTRENGTH (85*FRACUNIT/100)
+#define BOTSTRAIGHTANGLE (ANG10)
+
 // Point for bots to aim for
 struct botprediction_t
 {

src/k_hud.cpp

@@ -7096,6 +7096,7 @@ static void K_DrawBotDebugger(void)
 	V_DrawSmallString(8, 70, 0, va("Bot modifier: %.2f", FixedToFloat(K_BotMapModifier())));
 
 	V_DrawSmallString(8, 76, 0, va("Prediction error: %d", bot->botvars.predictionError));
+	V_DrawSmallString(8, 80, 0, va("Straight: %d", bot->botvars.straightawayTime));
 }
 
 static void K_DrawGPRankDebugger(void)

src/p_saveg.cpp

@@ -756,7 +756,8 @@ static void P_NetArchivePlayers(savebuffer_t *save)
 		WRITEUINT32(save->p, players[i].botvars.spindashconfirm);
 		WRITEUINT32(save->p, players[i].botvars.respawnconfirm);
 		WRITEUINT8(save->p, players[i].botvars.roulettePriority);
-		WRITEUINT32(save->p, players[i].botvars.rouletteTimeout);
+		WRITEINT32(save->p, players[i].botvars.rouletteTimeout);
+		WRITEINT16(save->p, players[i].botvars.straightawayTime);
 
 		// itemroulette_t
 		WRITEUINT8(save->p, players[i].itemRoulette.active);
@@ -1409,6 +1410,7 @@ static void P_NetUnArchivePlayers(savebuffer_t *save)
 		players[i].botvars.respawnconfirm = READUINT32(save->p);
 		players[i].botvars.roulettePriority = READUINT8(save->p);
 		players[i].botvars.rouletteTimeout = READUINT32(save->p);
+		players[i].botvars.straightawayTime = READINT16(save->p);
 
 		// itemroulette_t
 		players[i].itemRoulette.active = (boolean)READUINT8(save->p);