From: notaz <notasas@gmail.com>
Date: Fri, 16 May 2025 21:04:40 +0000 (+0300)
Subject: in_sdl: improve joy support
X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e3c0b8868e93724929af74bbff624d0b7f076119;p=libpicofe.git

in_sdl: improve joy support

- avoid event flood for analog->udlr mapping
- ability to disable this mapping
- basic hat support
---

diff --git a/in_sdl.c b/in_sdl.c
index 3fdc01a..15c8c22 100644
--- a/in_sdl.c
+++ b/in_sdl.c
@@ -19,13 +19,20 @@
 typedef unsigned long keybits_t;
 #define KEYBITS_WORD_BITS (sizeof(keybits_t) * 8)
 
+#ifndef ARRAY_SIZE
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0]))
+#endif
+
 struct in_sdl_state {
 	const in_drv_t *drv;
 	SDL_Joystick *joy;
 	int joy_id;
 	int numaxes;
 	int axis_keydown[2];
-	int redraw;
+	int hat_down;
+	unsigned int redraw:1;
+	unsigned int abs_to_udlr:1;
+	unsigned int hat_warned:1;
 	SDL_Event revent;
 	SDL_Event mevent; // last mouse event
 	keybits_t keystate[SDLK_LAST / KEYBITS_WORD_BITS + 1];
@@ -169,6 +176,23 @@ static const char * const in_sdl_keys[SDLK_LAST] = {
 	[SDLK_COMPOSE] = "compose",
 };
 
+static struct in_sdl_state *state_alloc(void)
+{
+	struct in_sdl_state *state;
+	size_t i;
+
+	state = calloc(1, sizeof(*state));
+	if (state == NULL) {
+		fprintf(stderr, "in_sdl: OOM\n");
+		return NULL;
+	}
+
+	state->abs_to_udlr = 1;
+	for (i = 0; i < ARRAY_SIZE(state->axis_keydown); i++)
+		state->axis_keydown[i] = -1;
+	return state;
+}
+
 static void in_sdl_probe(const in_drv_t *drv)
 {
 	const struct in_pdata *pdata = drv->pdata;
@@ -181,11 +205,8 @@ static void in_sdl_probe(const in_drv_t *drv)
 	if (pdata->key_names)
 		key_names = pdata->key_names;
 
-	state = calloc(1, sizeof(*state));
-	if (state == NULL) {
-		fprintf(stderr, "in_sdl: OOM\n");
+	if (!(state = state_alloc()))
 		return;
-	}
 
 	state->drv = drv;
 	in_register(IN_SDL_PREFIX "keys", -1, state, SDLK_LAST,
@@ -201,11 +222,8 @@ static void in_sdl_probe(const in_drv_t *drv)
 		if (joy == NULL)
 			continue;
 
-		state = calloc(1, sizeof(*state));
-		if (state == NULL) {
-			fprintf(stderr, "in_sdl: OOM\n");
+		if (!(state = state_alloc()))
 			break;
-		}
 		state->joy = joy;
 		state->joy_id = i;
 		state->numaxes = SDL_JoystickNumAxes(joy);
@@ -289,42 +307,39 @@ static int handle_event(struct in_sdl_state *state, SDL_Event *event,
 static int handle_joy_event(struct in_sdl_state *state, SDL_Event *event,
 	int *kc_out, int *down_out, int *emu_out)
 {
-	int kc = -1, down = 0, emu = 0, ret = 0;
+	static const int hat2key[4] = { SDLK_UP, SDLK_RIGHT, SDLK_DOWN, SDLK_LEFT };
+	int kc = -1, kc_prev = -1, down = 0, emu = 0, ret = 0, i, val, xor;
 
 	/* TODO: remaining axis */
 	switch (event->type) {
 	case SDL_JOYAXISMOTION:
+		if (!state->abs_to_udlr)
+			return -1;
 		if (event->jaxis.which != state->joy_id)
 			return -2;
 		if (event->jaxis.axis > 1)
 			break;
-		if (-16384 <= event->jaxis.value && event->jaxis.value <= 16384) {
-			kc = state->axis_keydown[event->jaxis.axis];
-			state->axis_keydown[event->jaxis.axis] = 0;
-			ret = 1;
-		}
-		else if (event->jaxis.value < -16384) {
-			kc = state->axis_keydown[event->jaxis.axis];
-			if (kc) {
-				emu |= get_keystate(state->emu_keys, kc);
-				update_keystate(state->keystate, kc, 0);
-			}
+		if (event->jaxis.value < -16384) {
 			kc = event->jaxis.axis ? SDLK_UP : SDLK_LEFT;
-			state->axis_keydown[event->jaxis.axis] = kc;
 			down = 1;
-			ret = 1;
 		}
 		else if (event->jaxis.value > 16384) {
-			kc = state->axis_keydown[event->jaxis.axis];
-			if (kc) {
-				emu |= get_keystate(state->emu_keys, kc);
-				update_keystate(state->keystate, kc, 0);
-			}
 			kc = event->jaxis.axis ? SDLK_DOWN : SDLK_RIGHT;
-			state->axis_keydown[event->jaxis.axis] = kc;
 			down = 1;
-			ret = 1;
 		}
+		kc_prev = state->axis_keydown[event->jaxis.axis];
+		state->axis_keydown[event->jaxis.axis] = kc;
+		if (kc == kc_prev)
+			return -1; // no simulated key change
+		if (kc >= 0 && kc_prev >= 0) {
+			// must release the old key first
+			state->axis_keydown[event->jaxis.axis] = -1;
+			kc = kc_prev;
+			down = 0;
+		}
+		else if (kc_prev >= 0)
+			kc = kc_prev;
+		ret = 1;
 		break;
 
 	case SDL_JOYBUTTONDOWN:
@@ -335,7 +350,29 @@ static int handle_joy_event(struct in_sdl_state *state, SDL_Event *event,
 		down = event->jbutton.state == SDL_PRESSED;
 		ret = 1;
 		break;
+	case SDL_JOYHATMOTION:
+		if (event->jhat.which != state->joy_id)
+			return -2;
+		if (event->jhat.hat != 0)
+			return -1; // todo?
+		xor = event->jhat.value ^ state->hat_down;
+		val = state->hat_down = event->jhat.value;
+		for (i = 0; i < 4; i++, xor >>= 1, val >>= 1) {
+			if (xor & 1) {
+				down = val & 1;
+				kc = hat2key[i];
+				ret = 1;
+				break;
+			}
+		}
+		if ((!ret || (xor >> ret)) && !state->hat_warned) {
+			// none, more than 1, or upper bits changed
+			fprintf(stderr, "in_sdl: unexpected hat behavior\n");
+			state->hat_warned = 1;
+		}
+		break;
 	default:
+		//printf("joy ev %d\n", event->type);
 		return -1;
 	}
 
@@ -366,7 +403,7 @@ static int collect_events(struct in_sdl_state *state, int *one_kc, int *one_down
 
 	SDL_PumpEvents();
 
-	maxcount = sizeof(events) / sizeof(events[0]);
+	maxcount = ARRAY_SIZE(events);
 	if ((count = SDL_PeepEvents(events, maxcount, SDL_GETEVENT, mask)) > 0) {
 		for (i = 0; i < count; i++) {
 			event = &events[i];
@@ -628,6 +665,31 @@ static int in_sdl_get_config(void *drv_data, enum in_cfg_opt what, int *val)
 	case IN_CFG_ABS_AXIS_COUNT:
 		*val = state->numaxes;
 		break;
+	case IN_CFG_ANALOG_MAP_ULDR:
+		*val = state->abs_to_udlr;
+		break;
+	default:
+		return -1;
+	}
+
+	return 0;
+}
+
+static int in_sdl_set_config(void *drv_data, enum in_cfg_opt what, int val)
+{
+	struct in_sdl_state *state = drv_data;
+	size_t i;
+
+	switch (what) {
+	case IN_CFG_ANALOG_MAP_ULDR:
+		state->abs_to_udlr = val ? 1 : 0;
+		for (i = 0; !val && i < ARRAY_SIZE(state->axis_keydown); i++) {
+			if (state->axis_keydown[i] < 0)
+				continue;
+			update_keystate(state->keystate, state->axis_keydown[i], 0);
+			state->axis_keydown[i] = -1;
+		}
+		break;
 	default:
 		return -1;
 	}
@@ -648,6 +710,7 @@ static const in_drv_t in_sdl_drv = {
 	.menu_translate  = in_sdl_menu_translate,
 	.clean_binds     = in_sdl_clean_binds,
 	.get_config      = in_sdl_get_config,
+	.set_config      = in_sdl_set_config,
 };
 
 int in_sdl_init(const struct in_pdata *pdata, void (*handler)(void *event))
diff --git a/input.h b/input.h
index 4fcdbde..5ac73c9 100644
--- a/input.h
+++ b/input.h
@@ -61,6 +61,7 @@ enum in_cfg_opt {
 	IN_CFG_ABS_DEAD_ZONE,	/* dead zone for analog-digital mapping */
 	IN_CFG_ABS_AXIS_COUNT,	/* number of abs axes (ro) */
 	IN_CFG_DEFAULT_DEV,
+	IN_CFG_ANALOG_MAP_ULDR,
 };
 
 enum {
diff --git a/linux/in_evdev.c b/linux/in_evdev.c
index 49bfa37..b3fb825 100644
--- a/linux/in_evdev.c
+++ b/linux/in_evdev.c
@@ -437,6 +437,8 @@ static int in_evdev_get_config(void *drv_data, enum in_cfg_opt what, int *val)
 	case IN_CFG_ABS_AXIS_COUNT:
 		*val = dev->abs_count;
 		break;
+	case IN_CFG_ANALOG_MAP_ULDR:
+		*val = dev->abs_to_digital;
 	default:
 		return -1;
 	}
@@ -463,6 +465,8 @@ static int in_evdev_set_config(void *drv_data, enum in_cfg_opt what, int val)
 		else if (dev->abs_lzone >= tmp)
 			dev->abs_lzone = tmp - 1;
 		break;
+	case IN_CFG_ANALOG_MAP_ULDR:
+		dev->abs_to_digital = val;
 	default:
 		return -1;
 	}