Add: settings to limit your fast-forward game speed

By default this setting is set to 2500% normal game speed.

17 files changed, 84 insertions, 69 deletions

diff --git a/src/gfx.cpp b/src/gfx.cpp
index 50f00805e..30efc947c 100644
--- a/src/gfx.cpp
+++ b/src/gfx.cpp
@@ -34,7 +34,7 @@ byte _support8bpp;
 CursorVars _cursor;
 bool _ctrl_pressed;   ///< Is Ctrl pressed?
 bool _shift_pressed;  ///< Is Shift pressed?
-byte _fast_forward;
+uint16 _game_speed = 100; ///< Current game-speed; 100 is 1x, 0 is infinite.
 bool _left_button_down;     ///< Is left mouse button pressed?
 bool _left_button_clicked;  ///< Is left mouse button clicked?
 bool _right_button_down;    ///< Is right mouse button pressed?
@@ -1905,3 +1905,12 @@ void UpdateGUIZoom()
 		_font_zoom = static_cast<ZoomLevel>(_font_zoom_cfg);
 	}
 }
+
+void ChangeGameSpeed(bool enable_fast_forward)
+{
+	if (enable_fast_forward) {
+		_game_speed = _settings_client.gui.fast_forward_speed_limit;
+	} else {
+		_game_speed = 100;
+	}
+}
diff --git a/src/gfx_func.h b/src/gfx_func.h
index 8695fa0e2..e8f7d0345 100644
--- a/src/gfx_func.h
+++ b/src/gfx_func.h
@@ -54,7 +54,7 @@ extern byte _support8bpp;
 extern CursorVars _cursor;
 extern bool _ctrl_pressed;   ///< Is Ctrl pressed?
 extern bool _shift_pressed;  ///< Is Shift pressed?
-extern byte _fast_forward;
+extern uint16 _game_speed;
 
 extern bool _left_button_down;
 extern bool _left_button_clicked;
@@ -73,6 +73,7 @@ void HandleTextInput(const char *str, bool marked = false, const char *caret = n
 void HandleCtrlChanged();
 void HandleMouseEvents();
 void UpdateWindows();
+void ChangeGameSpeed(bool enable_fast_forward);
 
 void DrawMouseCursor();
 void ScreenSizeChanged();
diff --git a/src/lang/english.txt b/src/lang/english.txt
index 524dbbd2c..9935f3a56 100644
--- a/src/lang/english.txt
+++ b/src/lang/english.txt
@@ -1453,6 +1453,10 @@ STR_CONFIG_SETTING_EXPENSES_LAYOUT                              :Group expenses
 STR_CONFIG_SETTING_EXPENSES_LAYOUT_HELPTEXT                     :Define the layout for the company expenses window
 STR_CONFIG_SETTING_AUTO_REMOVE_SIGNALS                          :Automatically remove signals during rail construction: {STRING2}
 STR_CONFIG_SETTING_AUTO_REMOVE_SIGNALS_HELPTEXT                 :Automatically remove signals during rail construction if the signals are in the way. Note that this can potentially lead to train crashes.
+STR_CONFIG_SETTING_FAST_FORWARD_SPEED_LIMIT                     :Fast forward speed limit: {STRING2}
+STR_CONFIG_SETTING_FAST_FORWARD_SPEED_LIMIT_HELPTEXT            :Limit on how fast the game goes when fast forward is enabled. 0 = no limit (as fast as your computer allows). Values below 100% slow the game down. The upper-limit depends on the specification of your computer and can vary depending on the game.
+STR_CONFIG_SETTING_FAST_FORWARD_SPEED_LIMIT_VAL                 :{NUM}% normal game speed
+STR_CONFIG_SETTING_FAST_FORWARD_SPEED_LIMIT_ZERO                :No limit (as fast as your computer allows)
 
 STR_CONFIG_SETTING_SOUND_TICKER                                 :News ticker: {STRING2}
 STR_CONFIG_SETTING_SOUND_TICKER_HELPTEXT                        :Play sound for summarised news messages
diff --git a/src/misc.cpp b/src/misc.cpp
index dcb04fa02..c46a1c11d 100644
--- a/src/misc.cpp
+++ b/src/misc.cpp
@@ -64,7 +64,7 @@ void InitializeGame(uint size_x, uint size_y, bool reset_date, bool reset_settin
 	AllocateMap(size_x, size_y);
 
 	_pause_mode = PM_UNPAUSED;
-	_fast_forward = 0;
+	_game_speed = 100;
 	_tick_counter = 0;
 	_cur_tileloop_tile = 1;
 	_thd.redsq = INVALID_TILE;
diff --git a/src/saveload/saveload.cpp b/src/saveload/saveload.cpp
index 18f7a17b1..dcfcc9f43 100644
--- a/src/saveload/saveload.cpp
+++ b/src/saveload/saveload.cpp
@@ -208,7 +208,7 @@ struct SaveLoadParams {
 	StringID error_str;                  ///< the translatable error message to show
 	char *extra_msg;                     ///< the error message
 
-	byte ff_state;                       ///< The state of fast-forward when saving started.
+	uint16 game_speed;                   ///< The game speed when saving started.
 	bool saveinprogress;                 ///< Whether there is currently a save in progress.
 };
 
@@ -2442,8 +2442,8 @@ static inline void ClearSaveLoadState()
  */
 static void SaveFileStart()
 {
-	_sl.ff_state = _fast_forward;
-	_fast_forward = 0;
+	_sl.game_speed = _game_speed;
+	_game_speed = 100;
 	SetMouseCursorBusy(true);
 
 	InvalidateWindowData(WC_STATUS_BAR, 0, SBI_SAVELOAD_START);
@@ -2453,7 +2453,7 @@ static void SaveFileStart()
 /** Update the gui accordingly when saving is done and release locks on saveload. */
 static void SaveFileDone()
 {
-	if (_game_mode != GM_MENU) _fast_forward = _sl.ff_state;
+	if (_game_mode != GM_MENU) _game_speed = _sl.game_speed;
 	SetMouseCursorBusy(false);
 
 	InvalidateWindowData(WC_STATUS_BAR, 0, SBI_SAVELOAD_FINISH);
diff --git a/src/settings_gui.cpp b/src/settings_gui.cpp
index bec549890..f89b3f718 100644
--- a/src/settings_gui.cpp
+++ b/src/settings_gui.cpp
@@ -1468,6 +1468,7 @@ static SettingsContainer &GetSettingsTree()
 				construction->Add(new SettingEntry("gui.default_rail_type"));
 			}
 
+			interface->Add(new SettingEntry("gui.fast_forward_speed_limit"));
 			interface->Add(new SettingEntry("gui.autosave"));
 			interface->Add(new SettingEntry("gui.toolbar_pos"));
 			interface->Add(new SettingEntry("gui.statusbar_pos"));
diff --git a/src/settings_type.h b/src/settings_type.h
index 11298cfa7..f2c591f64 100644
--- a/src/settings_type.h
+++ b/src/settings_type.h
@@ -148,6 +148,7 @@ struct GUISettings {
 	bool   show_newgrf_name;                 ///< Show the name of the NewGRF in the build vehicle window
 	bool   auto_remove_signals;              ///< automatically remove signals when in the way during rail construction
 	uint16 refresh_rate;                     ///< How often we refresh the screen (time between draw-ticks).
+	uint16 fast_forward_speed_limit;         ///< Game speed to use when fast-forward is enabled.
 
 	uint16 console_backlog_timeout;          ///< the minimum amount of time items should be in the console backlog before they will be removed in ~3 seconds granularity.
 	uint16 console_backlog_length;           ///< the minimum amount of items in the console backlog before items will be removed.
diff --git a/src/table/settings.ini b/src/table/settings.ini
index 5907c09a7..52602a3df 100644
--- a/src/table/settings.ini
+++ b/src/table/settings.ini
@@ -3364,6 +3364,20 @@ max      = 1000
 cat      = SC_EXPERT
 startup  = true
 
+[SDTC_VAR]
+var      = gui.fast_forward_speed_limit
+type     = SLE_UINT16
+flags    = SLF_NOT_IN_SAVE | SLF_NO_NETWORK_SYNC
+guiflags = SGF_0ISDISABLED | SGF_NO_NETWORK
+def      = 2500
+min      = 0
+max      = 100000
+interval = 10
+str      = STR_CONFIG_SETTING_FAST_FORWARD_SPEED_LIMIT
+strhelp  = STR_CONFIG_SETTING_FAST_FORWARD_SPEED_LIMIT_HELPTEXT
+strval   = STR_CONFIG_SETTING_FAST_FORWARD_SPEED_LIMIT_VAL
+cat      = SC_BASIC
+
 [SDTC_BOOL]
 var      = sound.news_ticker
 flags    = SLF_NOT_IN_SAVE | SLF_NO_NETWORK_SYNC
diff --git a/src/toolbar_gui.cpp b/src/toolbar_gui.cpp
index 6a851d2b5..ea50661e4 100644
--- a/src/toolbar_gui.cpp
+++ b/src/toolbar_gui.cpp
@@ -283,7 +283,8 @@ static CallBackFunction ToolbarPauseClick(Window *w)
  */
 static CallBackFunction ToolbarFastForwardClick(Window *w)
 {
-	_fast_forward ^= true;
+	ChangeGameSpeed(_game_speed == 100);
+
 	if (_settings_client.sound.click_beep) SndPlayFx(SND_15_BEEP);
 	return CBF_NONE;
 }
@@ -2127,7 +2128,7 @@ struct MainToolbarWindow : Window {
 			this->SetWidgetDirty(WID_TN_PAUSE);
 		}
 
-		if (this->IsWidgetLowered(WID_TN_FAST_FORWARD) != !!_fast_forward) {
+		if (this->IsWidgetLowered(WID_TN_FAST_FORWARD) != (_game_speed != 100)) {
 			this->ToggleWidgetLoweredState(WID_TN_FAST_FORWARD);
 			this->SetWidgetDirty(WID_TN_FAST_FORWARD);
 		}
@@ -2508,7 +2509,7 @@ struct ScenarioEditorToolbarWindow : Window {
 			this->SetDirty();
 		}
 
-		if (this->IsWidgetLowered(WID_TE_FAST_FORWARD) != !!_fast_forward) {
+		if (this->IsWidgetLowered(WID_TE_FAST_FORWARD) != (_game_speed != 100)) {
 			this->ToggleWidgetLoweredState(WID_TE_FAST_FORWARD);
 			this->SetDirty();
 		}
diff --git a/src/video/allegro_v.cpp b/src/video/allegro_v.cpp
index 208de06c4..a01a9a5e7 100644
--- a/src/video/allegro_v.cpp
+++ b/src/video/allegro_v.cpp
@@ -19,7 +19,6 @@
 #include "../gfx_func.h"
 #include "../rev.h"
 #include "../blitter/factory.hpp"
-#include "../network/network.h"
 #include "../core/random_func.hpp"
 #include "../core/math_func.hpp"
 #include "../framerate_type.h"
@@ -457,17 +456,12 @@ void VideoDriver_Allegro::InputLoop()
 	_shift_pressed = !!(key_shifts & KB_SHIFT_FLAG);
 
 #if defined(_DEBUG)
-	if (_shift_pressed)
+	this->fast_forward_key_pressed = _shift_pressed;
 #else
 	/* Speedup when pressing tab, except when using ALT+TAB
 	 * to switch to another application. */
-	if (key[KEY_TAB] && (key_shifts & KB_ALT_FLAG) == 0)
+	this->fast_forward_key_pressed = key[KEY_TAB] && (key_shifts & KB_ALT_FLAG) == 0;
 #endif
-	{
-		if (!_networking && _game_mode != GM_MENU) _fast_forward |= 2;
-	} else if (_fast_forward & 2) {
-		_fast_forward = 0;
-	}
 
 	/* Determine which directional keys are down. */
 	_dirkeys =
diff --git a/src/video/cocoa/cocoa_v.mm b/src/video/cocoa/cocoa_v.mm
index dd49cd211..523a408b1 100644
--- a/src/video/cocoa/cocoa_v.mm
+++ b/src/video/cocoa/cocoa_v.mm
@@ -33,7 +33,6 @@
 #include "cocoa_wnd.h"
 #include "../../blitter/factory.hpp"
 #include "../../framerate_type.h"
-#include "../../network/network.h"
 #include "../../gfx_func.h"
 #include "../../thread.h"
 #include "../../core/random_func.hpp"
@@ -420,14 +419,10 @@ void VideoDriver_Cocoa::InputLoop()
 	_shift_pressed = (cur_mods & NSShiftKeyMask) != 0;
 
 #if defined(_DEBUG)
-	if (_shift_pressed) {
+	this->fast_forward_key_pressed = _shift_pressed;
 #else
-	if (_tab_is_down) {
+	this->fast_forward_key_pressed = _tab_is_down;
 #endif
-		if (!_networking && _game_mode != GM_MENU) _fast_forward |= 2;
-	} else if (_fast_forward & 2) {
-		_fast_forward = 0;
-	}
 
 	if (old_ctrl_pressed != _ctrl_pressed) HandleCtrlChanged();
 }
diff --git a/src/video/dedicated_v.cpp b/src/video/dedicated_v.cpp
index 81d634ce5..22b9dbb1a 100644
--- a/src/video/dedicated_v.cpp
+++ b/src/video/dedicated_v.cpp
@@ -277,7 +277,7 @@ void VideoDriver_Dedicated::MainLoop()
 	while (!_exit_game) {
 		if (!_dedicated_forks) DedicatedHandleKeyInput();
 
-		_fast_forward = _ddc_fastforward;
+		ChangeGameSpeed(_ddc_fastforward);
 		this->Tick();
 		this->SleepTillNextTick();
 	}
diff --git a/src/video/sdl2_v.cpp b/src/video/sdl2_v.cpp
index af20e8420..f122a2921 100644
--- a/src/video/sdl2_v.cpp
+++ b/src/video/sdl2_v.cpp
@@ -12,7 +12,6 @@
 #include "../gfx_func.h"
 #include "../rev.h"
 #include "../blitter/factory.hpp"
-#include "../network/network.h"
 #include "../thread.h"
 #include "../progress.h"
 #include "../core/random_func.hpp"
@@ -604,17 +603,12 @@ void VideoDriver_SDL_Base::InputLoop()
 	_shift_pressed = !!(mod & KMOD_SHIFT);
 
 #if defined(_DEBUG)
-	if (_shift_pressed)
+	this->fast_forward_key_pressed = _shift_pressed;
 #else
 	/* Speedup when pressing tab, except when using ALT+TAB
 	 * to switch to another application. */
-	if (keys[SDL_SCANCODE_TAB] && (mod & KMOD_ALT) == 0)
+	this->fast_forward_key_pressed = keys[SDL_SCANCODE_TAB] && (mod & KMOD_ALT) == 0;
 #endif /* defined(_DEBUG) */
-	{
-		if (!_networking && _game_mode != GM_MENU) _fast_forward |= 2;
-	} else if (_fast_forward & 2) {
-		_fast_forward = 0;
-	}
 
 	/* Determine which directional keys are down. */
 	_dirkeys =
diff --git a/src/video/sdl_v.cpp b/src/video/sdl_v.cpp
index 51327be16..f9ec2a86c 100644
--- a/src/video/sdl_v.cpp
+++ b/src/video/sdl_v.cpp
@@ -14,7 +14,6 @@
 #include "../gfx_func.h"
 #include "../rev.h"
 #include "../blitter/factory.hpp"
-#include "../network/network.h"
 #include "../thread.h"
 #include "../progress.h"
 #include "../core/random_func.hpp"
@@ -662,17 +661,12 @@ void VideoDriver_SDL::InputLoop()
 	_shift_pressed = !!(mod & KMOD_SHIFT);
 
 #if defined(_DEBUG)
-	if (_shift_pressed)
+	this->fast_forward_key_pressed = _shift_pressed;
 #else
 	/* Speedup when pressing tab, except when using ALT+TAB
 	 * to switch to another application. */
-	if (keys[SDLK_TAB] && (mod & KMOD_ALT) == 0)
+	this->fast_forward_key_pressed = keys[SDLK_TAB] && (mod & KMOD_ALT) == 0;
 #endif /* defined(_DEBUG) */
-	{
-		if (!_networking && _game_mode != GM_MENU) _fast_forward |= 2;
-	} else if (_fast_forward & 2) {
-		_fast_forward = 0;
-	}
 
 	/* Determine which directional keys are down. */
 	_dirkeys =
diff --git a/src/video/video_driver.cpp b/src/video/video_driver.cpp
index d528bbec7..bcd646abd 100644
--- a/src/video/video_driver.cpp
+++ b/src/video/video_driver.cpp
@@ -10,6 +10,7 @@
 #include "../stdafx.h"
 #include "../debug.h"
 #include "../core/random_func.hpp"
+#include "../network/network.h"
 #include "../gfx_func.h"
 #include "../progress.h"
 #include "../thread.h"
@@ -20,14 +21,10 @@ bool VideoDriver::Tick()
 {
 	auto cur_ticks = std::chrono::steady_clock::now();
 
-	if (cur_ticks >= this->next_game_tick || (_fast_forward && !_pause_mode)) {
-		if (_fast_forward && !_pause_mode) {
-			this->next_game_tick = cur_ticks + this->GetGameInterval();
-		} else {
-			this->next_game_tick += this->GetGameInterval();
-			/* Avoid next_game_tick getting behind more and more if it cannot keep up. */
-			if (this->next_game_tick < cur_ticks - ALLOWED_DRIFT * this->GetGameInterval()) this->next_game_tick = cur_ticks;
-		}
+	if (cur_ticks >= this->next_game_tick) {
+		this->next_game_tick += this->GetGameInterval();
+		/* Avoid next_game_tick getting behind more and more if it cannot keep up. */
+		if (this->next_game_tick < cur_ticks - ALLOWED_DRIFT * this->GetGameInterval()) this->next_game_tick = cur_ticks;
 
 		/* The game loop is the part that can run asynchronously.
 		 * The rest except sleeping can't. */
@@ -55,6 +52,16 @@ bool VideoDriver::Tick()
 
 		while (this->PollEvent()) {}
 		this->InputLoop();
+
+		/* Check if the fast-forward button is still pressed. */
+		if (fast_forward_key_pressed && !_networking && _game_mode != GM_MENU) {
+			ChangeGameSpeed(true);
+			this->fast_forward_via_key = true;
+		} else if (this->fast_forward_via_key) {
+			ChangeGameSpeed(false);
+			this->fast_forward_via_key = false;
+		}
+
 		::InputLoop();
 		UpdateWindows();
 		this->CheckPaletteAnim();
@@ -67,16 +74,13 @@ bool VideoDriver::Tick()
 
 void VideoDriver::SleepTillNextTick()
 {
-	/* If we are not in fast-forward, create some time between calls to ease up CPU usage. */
-	if (!_fast_forward || _pause_mode) {
-		/* See how much time there is till we have to process the next event, and try to hit that as close as possible. */
-		auto next_tick = std::min(this->next_draw_tick, this->next_game_tick);
-		auto now = std::chrono::steady_clock::now();
+	/* See how much time there is till we have to process the next event, and try to hit that as close as possible. */
+	auto next_tick = std::min(this->next_draw_tick, this->next_game_tick);
+	auto now = std::chrono::steady_clock::now();
 
-		if (next_tick > now) {
-			this->UnlockVideoBuffer();
-			std::this_thread::sleep_for(next_tick - now);
-			this->LockVideoBuffer();
-		}
+	if (next_tick > now) {
+		this->UnlockVideoBuffer();
+		std::this_thread::sleep_for(next_tick - now);
+		this->LockVideoBuffer();
 	}
 }
diff --git a/src/video/video_driver.hpp b/src/video/video_driver.hpp
index 2e478def9..938dd84bf 100644
--- a/src/video/video_driver.hpp
+++ b/src/video/video_driver.hpp
@@ -13,6 +13,7 @@
 #include "../driver.h"
 #include "../core/geometry_type.hpp"
 #include "../core/math_func.hpp"
+#include "../gfx_func.h"
 #include "../settings_type.h"
 #include "../zoom_type.h"
 #include <chrono>
@@ -268,7 +269,12 @@ protected:
 
 	std::chrono::steady_clock::duration GetGameInterval()
 	{
-		return std::chrono::milliseconds(MILLISECONDS_PER_TICK);
+		/* If we are paused, run on normal speed. */
+		if (_pause_mode) return std::chrono::milliseconds(MILLISECONDS_PER_TICK);
+		/* Infinite speed, as quickly as you can. */
+		if (_game_speed == 0) return std::chrono::microseconds(0);
+
+		return std::chrono::microseconds(MILLISECONDS_PER_TICK * 1000 * 100 / _game_speed);
 	}
 
 	std::chrono::steady_clock::duration GetDrawInterval()
@@ -278,6 +284,9 @@ protected:
 
 	std::chrono::steady_clock::time_point next_game_tick;
 	std::chrono::steady_clock::time_point next_draw_tick;
+
+	bool fast_forward_key_pressed; ///< The fast-forward key is being pressed.
+	bool fast_forward_via_key; ///< The fast-forward was enabled by key press.
 };
 
 #endif /* VIDEO_VIDEO_DRIVER_HPP */
diff --git a/src/video/win32_v.cpp b/src/video/win32_v.cpp
index 131a991f3..d5f752be9 100644
--- a/src/video/win32_v.cpp
+++ b/src/video/win32_v.cpp
@@ -13,7 +13,6 @@
 #include "../os/windows/win32.h"
 #include "../rev.h"
 #include "../blitter/factory.hpp"
-#include "../network/network.h"
 #include "../core/geometry_func.hpp"
 #include "../core/math_func.hpp"
 #include "../core/random_func.hpp"
@@ -831,17 +830,12 @@ void VideoDriver_Win32Base::InputLoop()
 	_shift_pressed = this->has_focus && GetAsyncKeyState(VK_SHIFT) < 0;
 
 #if defined(_DEBUG)
-	if (_shift_pressed)
+	this->fast_forward_key_pressed = _shift_pressed;
 #else
 	/* Speedup when pressing tab, except when using ALT+TAB
 	 * to switch to another application. */
-	if (this->has_focus && GetAsyncKeyState(VK_TAB) < 0 && GetAsyncKeyState(VK_MENU) >= 0)
+	this->fast_forward_key_pressed = this->has_focus && GetAsyncKeyState(VK_TAB) < 0 && GetAsyncKeyState(VK_MENU) >= 0;
 #endif
-	{
-		if (!_networking && _game_mode != GM_MENU) _fast_forward |= 2;
-	} else if (_fast_forward & 2) {
-		_fast_forward = 0;
-	}
 
 	/* Determine which directional keys are down. */
 	if (this->has_focus) {