From ca11cdea27bd8fb637129a8d5b166af86832efed Mon Sep 17 00:00:00 2001
From: Layla Marchant <diligentcircle@riseup.net>
Date: Mon, 27 Jul 2020 11:29:35 -0400
Subject: [PATCH] Implemented use of the game controller SDL API.

Fixes #7

Designed to use the game controller API if possible, or fall back
to the regular joystick API otherwise.

This also makes it so that all connected controllers can be used,
rather than just the first one.
---
 src/defs.h   |   1 +
 src/engine.c |  28 ++++++++++++--
 src/player.c | 101 +++++++++++++++++++++++++++++++++++++++++++++++----
 3 files changed, 119 insertions(+), 11 deletions(-)

diff --git a/src/defs.h b/src/defs.h
index e0f9da0..cc3df57 100644
--- a/src/defs.h
+++ b/src/defs.h
@@ -33,6 +33,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define RANDRANGE(x, y) (((x) < (y)) ? ((x) + (rand() % (long)(1 + (y) - (x)))) : (x))
 #define DRAND ((double)rand() / RAND_MAX)
 #define _(s) gettext(s)
+#define CSDLP(x) (((x) == SDL_PRESSED) ? 1 : 0)
 
 // A soft dependency defines these as well, so check if they are
 // defined before defining (avoids compiler warnings)
diff --git a/src/engine.c b/src/engine.c
index 3988b45..f159258 100644
--- a/src/engine.c
+++ b/src/engine.c
@@ -265,6 +265,9 @@ void engine_setMode()
 	int autoPause = 0;
 	int radioLife = DEFAULT_RADIO_LIFE;
 	char lang[STRMAX_SHORT];
+	int i;
+	int use_gc;
+
 	strcpy(lang, "default");
 
 	strcpy(engine.configDirectory, "");
@@ -272,7 +275,7 @@ void engine_setMode()
 	engine_setupConfigDirectory();
 
 	/* Initialize the SDL library */
-	if (SDL_Init(SDL_INIT_VIDEO|SDL_INIT_AUDIO|SDL_INIT_JOYSTICK) < 0)
+	if (SDL_Init(SDL_INIT_VIDEO|SDL_INIT_AUDIO|SDL_INIT_JOYSTICK|SDL_INIT_GAMECONTROLLER) < 0)
 	{
 		printf("Couldn't initialize SDL: %s\n", SDL_GetError());
 		exit(1);
@@ -329,8 +332,27 @@ void engine_setMode()
 	SDL_ShowCursor(SDL_DISABLE);
 	SDL_EventState(SDL_MOUSEMOTION, SDL_DISABLE);
 
-	SDL_JoystickEventState(SDL_ENABLE);
-	SDL_JoystickOpen(0);
+	// Determine if the GameController API can be used
+	use_gc = 1;
+	for (i=0; i<SDL_NumJoysticks(); i++) {
+		if (!SDL_IsGameController(i)) {
+			use_gc = 0;
+			break;
+		}
+	}
+	
+	if (use_gc)
+		SDL_GameControllerEventState(SDL_ENABLE);
+	else
+		SDL_JoystickEventState(SDL_ENABLE);
+	
+	// Open controllers
+	for (i=0; i<SDL_NumJoysticks(); i++) {
+		if (use_gc)
+			SDL_GameControllerOpen(i);
+		else
+			SDL_JoystickOpen(i);
+	}
 }
 
 void engine_setFullscreen(int value)
diff --git a/src/player.c b/src/player.c
index 547549c..601e602 100644
--- a/src/player.c
+++ b/src/player.c
@@ -263,8 +263,10 @@ void player_getInput()
 			case SDL_MOUSEBUTTONDOWN:
 				if (engine.gameSection == SECTION_INTERMISSION)
 				{
-					if (engine.event.button.button == SDL_BUTTON_LEFT) engine.keyState[KEY_FIRE] = 1;
-					if (engine.event.button.button == SDL_BUTTON_RIGHT) engine.keyState[KEY_ALTFIRE] = 1;
+					if (engine.event.button.button == SDL_BUTTON_LEFT)
+						engine.keyState[KEY_FIRE] = 1;
+					if (engine.event.button.button == SDL_BUTTON_RIGHT)
+						engine.keyState[KEY_ALTFIRE] = 1;
 				}
 				break;
 
@@ -289,24 +291,74 @@ void player_getInput()
 				{
 					case 0:
 					case 3:
-						engine.keyState[KEY_ALTFIRE] = engine.event.jbutton.state;
+						engine.keyState[KEY_ALTFIRE] = CSDLP(
+							engine.event.jbutton.state);
 						break;
 					case 1:
 					case 2:
-						engine.keyState[KEY_FIRE] = engine.event.jbutton.state;
+						engine.keyState[KEY_FIRE] = CSDLP(
+							engine.event.jbutton.state);
 						break;
 					case 4:
 					case 6:
-						engine.keyState[KEY_ESCAPE] = engine.event.jbutton.state;
+						engine.keyState[KEY_ESCAPE] = CSDLP(
+							engine.event.jbutton.state);
 						break;
 					case 5:
 					case 7:
 					case 8:
-						engine.keyState[KEY_SWITCH] = engine.event.jbutton.state;
+						engine.keyState[KEY_SWITCH] = CSDLP(
+							engine.event.jbutton.state);
 						break;
 					case 9:
-						if (engine.event.jbutton.state)
-							engine.keyState[KEY_PAUSE] = 1;
+						engine.keyState[KEY_PAUSE] = CSDLP(
+							engine.event.jbutton.state);
+						break;
+				}
+				break;
+			
+			case SDL_CONTROLLERBUTTONDOWN:
+			case SDL_CONTROLLERBUTTONUP:
+				switch (engine.event.cbutton.button)
+				{
+					case SDL_CONTROLLER_BUTTON_A:
+					case SDL_CONTROLLER_BUTTON_Y:
+						engine.keyState[KEY_ALTFIRE] = CSDLP(
+							engine.event.cbutton.state);
+						break;
+					case SDL_CONTROLLER_BUTTON_B:
+					case SDL_CONTROLLER_BUTTON_X:
+						engine.keyState[KEY_FIRE] = CSDLP(
+							engine.event.cbutton.state);
+						break;
+					case SDL_CONTROLLER_BUTTON_LEFTSHOULDER:
+						engine.keyState[KEY_ESCAPE] = CSDLP(
+							engine.event.cbutton.state);
+						break;
+					case SDL_CONTROLLER_BUTTON_BACK:
+					case SDL_CONTROLLER_BUTTON_RIGHTSHOULDER:
+						engine.keyState[KEY_SWITCH] = CSDLP(
+							engine.event.cbutton.state);
+						break;
+					case SDL_CONTROLLER_BUTTON_START:
+						engine.keyState[KEY_PAUSE] = CSDLP(
+							engine.event.cbutton.state);
+						break;
+					case SDL_CONTROLLER_BUTTON_DPAD_UP:
+						engine.keyState[KEY_UP] = CSDLP(
+							engine.event.cbutton.state);
+						break;
+					case SDL_CONTROLLER_BUTTON_DPAD_DOWN:
+						engine.keyState[KEY_DOWN] = CSDLP(
+							engine.event.cbutton.state);
+						break;
+					case SDL_CONTROLLER_BUTTON_DPAD_LEFT:
+						engine.keyState[KEY_LEFT] = CSDLP(
+							engine.event.cbutton.state);
+						break;
+					case SDL_CONTROLLER_BUTTON_DPAD_RIGHT:
+						engine.keyState[KEY_RIGHT] = CSDLP(
+							engine.event.cbutton.state);
 						break;
 				}
 				break;
@@ -348,6 +400,39 @@ void player_getInput()
 
 				break;
 
+			case SDL_CONTROLLERAXISMOTION:
+				if (engine.gameSection == SECTION_TITLE) {
+					if (engine.event.caxis.axis == SDL_CONTROLLER_AXIS_LEFTX)
+					{
+						joyleft = engine.event.caxis.value < -16384;
+						joyright = engine.event.caxis.value >= 16384;
+						if (joyleft != prevjoyleft)
+							engine.keyState[KEY_LEFT] = prevjoyleft = joyleft;
+						if (joyright != prevjoyright)
+							engine.keyState[KEY_RIGHT] = prevjoyright = joyright;
+					}
+					else if (engine.event.caxis.axis == SDL_CONTROLLER_AXIS_LEFTY)
+					{
+						joyup = engine.event.caxis.value < -16384;
+						joydown = engine.event.caxis.value >= 16384;
+						if (joyup != prevjoyup)
+							engine.keyState[KEY_UP] = prevjoyup = joyup;
+						if (joydown != prevjoydown)
+							engine.keyState[KEY_DOWN] = prevjoydown = joydown;
+					}
+				} else {
+					val = MIN(1, (double)(abs(engine.event.caxis.value)) / JS_MAX);
+					if (val < JS_DEADZONE)
+						val = 0;
+
+					if (engine.event.caxis.axis == SDL_CONTROLLER_AXIS_LEFTX)
+						engine.xaxis = copysign(val, engine.event.caxis.value);
+					else if (engine.event.caxis.axis == SDL_CONTROLLER_AXIS_LEFTY)
+						engine.yaxis = copysign(val, engine.event.caxis.value);
+				}
+
+				break;
+
 			case SDL_WINDOWEVENT:
 				if (engine.event.window.event == SDL_WINDOWEVENT_SIZE_CHANGED)
 				{