vigem-sdvxio: Add relative mode and address comments

doc/sdvxhook/vigem-sdvxio.md

@@ -1,24 +1,24 @@
-This application allows you to use any sdvxio backend to drive an XB360 controller.
+This application allows you to use any sdvxio backend, e.g. `sdvxio-kfca.dll`, to be available as a XBOX 360 game controller on windows.
 Thus, it allows you to use a real cab with *any* game that supports xinput.
 
 # Setup
-* Install ViGEmBus (https://github.com/ViGEm/ViGEmBus/releases)
+* Install [ViGEmBus](https://github.com/ViGEm/ViGEmBus/releases)
 * Place the following in the same folder as vigem-sdvxio:
-  * Get a copy of ViGEmClient.dll (https://bin.jvnv.net/file/ZgMJK/ViGEmClient.zip)
-  * Rename your corresponding sdvxio-device.dll to sdvxio.dll.
-* Run vigem-sdvxio.exe so that the config file gets created
-* Edit vigem-sdvxio.conf so that the config file gets created as needed
+  * Get a copy of [ViGEmClient.dll](https://bin.jvnv.net/file/ZgMJK/ViGEmClient.zip) (or from bemanitools-supplements)
+  * Rename your corresponding `sdvxio-XXX.dll`, e.g. `sdvxio-kfca.dll`, to `sdvxio.dll`.
+* Run `vigem-sdvxio.exe` so that the config file gets created
+* Edit `vigem-sdvxio.conf` so that the config file gets created as needed
 
 # Usage
-* Run vigem-sdvxio.exe
+* Run `vigem-sdvxio.exe`
 * To quit the program, hit the TEST + SERVICE button at the same time
 
 # Mapping
 * BT ABCD are mapped to ABXY
 * FX LR are mapped to LB/RB
-* VOL LR are mapped to L/R thumbstick X
+* VOL LR are mapped to L thumbstick X/Y (either in absolute or relative mode depending on the config)
 
-# Additional Notes For Cabinets:
-* Make sure that you follow the instructions exactly from the release page (Prerequisites for Windows 7)
+# Additional Notes For Cabinets (Running on embedded Windows 7):
+* Make sure that you follow the instructions exactly from the release page ([Prerequisites for Windows 7](https://github.com/ViGEm/ViGEmBus/wiki/Prerequisites-for-Windows-7))
 * If you get an error while trying to install KB3033929, re-enable windows update
 * Make sure to ewfmgr C: -commit and reboot after installing the drivers (this only needs to be done once)

src/main/vigem-sdvxio/config-vigem-sdvxio.c

@@ -6,11 +6,13 @@
 #include "util/log.h"
 
 #define VIGEM_SDVXIO_CONFIG_ENABLE_KEYLIGHT_KEY "sdvxio.enable_keylight"
+#define VIGEM_SDVXIO_CONFIG_RELATIVE_ANALOG_KEY "sdvxio.use_relative_analog"
 #define VIGEM_SDVXIO_CONFIG_PWM_WINGS_KEY "sdvxio.pwm_wings"
 #define VIGEM_SDVXIO_CONFIG_PWM_CONTROLLER_KEY "sdvxio.pwm_controller"
 #define VIGEM_SDVXIO_CONFIG_AMP_VOLUME_KEY "sdvxio.amp_volume"
 
 #define VIGEM_SDVXIO_CONFIG_DEFAULT_ENABLE_KEYLIGHT_VALUE true
+#define VIGEM_SDVXIO_CONFIG_DEFAULT_RELATIVE_ANALOG_VALUE false
 #define VIGEM_SDVXIO_CONFIG_DEFAULT_PWM_WINGS_VALUE 128
 #define VIGEM_SDVXIO_CONFIG_DEFAULT_PWM_CONTROLLER_VALUE 64
 #define VIGEM_SDVXIO_CONFIG_DEFAULT_AMP_VOLUME_VALUE 48
@@ -23,6 +25,12 @@ void vigem_sdvxio_config_init(struct cconfig *config)
         VIGEM_SDVXIO_CONFIG_DEFAULT_ENABLE_KEYLIGHT_VALUE,
         "Enable input based key lighting");
 
+    cconfig_util_set_bool(
+        config,
+        VIGEM_SDVXIO_CONFIG_RELATIVE_ANALOG_KEY,
+        VIGEM_SDVXIO_CONFIG_DEFAULT_RELATIVE_ANALOG_VALUE,
+        "Use relative mode analog mapping");
+
     cconfig_util_set_int(
         config,
         VIGEM_SDVXIO_CONFIG_PWM_WINGS_KEY,
@@ -57,6 +65,18 @@ void vigem_sdvxio_config_get(
             VIGEM_SDVXIO_CONFIG_DEFAULT_ENABLE_KEYLIGHT_VALUE);
     }
 
+    if (!cconfig_util_get_bool(
+            config,
+            VIGEM_SDVXIO_CONFIG_RELATIVE_ANALOG_KEY,
+            &vigem_config->relative_analog,
+            VIGEM_SDVXIO_CONFIG_DEFAULT_RELATIVE_ANALOG_VALUE)) {
+        log_warning(
+            "Invalid value for key '%s' specified, fallback "
+            "to default '%d'",
+            VIGEM_SDVXIO_CONFIG_RELATIVE_ANALOG_KEY,
+            VIGEM_SDVXIO_CONFIG_DEFAULT_RELATIVE_ANALOG_VALUE);
+    }
+
     if (!cconfig_util_get_int(
             config,
             VIGEM_SDVXIO_CONFIG_PWM_WINGS_KEY,
@@ -94,7 +114,7 @@ void vigem_sdvxio_config_get(
     }
 }
 
-void get_vigem_sdvxio_config(struct vigem_sdvxio_config *config_out)
+bool get_vigem_sdvxio_config(struct vigem_sdvxio_config *config_out)
 {
     struct cconfig *config;
 
@@ -111,7 +131,7 @@ void get_vigem_sdvxio_config(struct vigem_sdvxio_config *config_out)
             "vigem-sdvxio",
             CCONFIG_CMD_USAGE_OUT_STDOUT)) {
         cconfig_finit(config);
-        exit(EXIT_FAILURE);
+        return false;
     }
 
     vigem_sdvxio_config_get(config_out, config);
@@ -125,4 +145,5 @@ void get_vigem_sdvxio_config(struct vigem_sdvxio_config *config_out)
     if (config_out->pwm_wings > 255) {
         config_out->pwm_wings = 255;
     }
+    return true;
 }

src/main/vigem-sdvxio/config-vigem-sdvxio.h

@@ -7,11 +7,12 @@
 
 struct vigem_sdvxio_config {
     bool enable_keylight;
+    bool relative_analog;
     int32_t pwm_wings;
     int32_t pwm_controller;
     int32_t amp_volume;
 };
 
-void get_vigem_sdvxio_config(struct vigem_sdvxio_config *config_out);
+bool get_vigem_sdvxio_config(struct vigem_sdvxio_config *config_out);
 
 #endif

src/main/vigem-sdvxio/main.c

@@ -15,12 +15,74 @@
 
 #include "vigem-sdvxio/config-vigem-sdvxio.h"
 
-int64_t convert_analog_to_s16(uint16_t val)
+#define ANALOG_FIXED_SENSITIVITY 1024
+
+int16_t convert_analog_to_s16(uint16_t val)
 {
     // val is 10 bit
     return (int64_t)(val * 64);
 }
 
+int16_t get_relative_delta(int16_t val, int16_t last)
+{
+    // val is 10 bit
+    const int16_t half_point = 512; // 2^9
+
+    int16_t delta = val - last;
+
+    if (delta > half_point) {
+        delta -= 1024;
+    }
+
+    if (delta < -half_point) {
+        delta += 1024;
+    }
+
+    // delta is now between (-512 - 512)
+    return delta;
+}
+
+int16_t filter_floor(int32_t value, int16_t floor) {
+    if (abs(value) < floor) {
+        return 0;
+    }
+    if (value > INT16_MAX) {
+        value = INT16_MAX;
+    }
+    if (value < INT16_MIN) {
+        value = INT16_MIN;
+    }
+
+    return value;
+}
+
+int32_t convert_relative_analog(
+    uint16_t val, uint16_t last, int32_t buffered_last, int16_t multiplier)
+{
+    int16_t delta = get_relative_delta(val, last);
+
+    if (delta == 0) {
+        // ease the stick back to 0 like a real stick would
+        return buffered_last / 2.f;
+    } else {
+        int64_t result = buffered_last;
+        result += delta * multiplier;
+
+        // we use an i32 to store the buffered value
+        // so that we can overshoot an i16 by up to 1.5x
+        // this allows users to stay at the min/max stick positions
+        // without perfect knob turning
+        if (result > INT16_MAX*1.5) {
+            result = INT16_MAX*1.5;
+        }
+        if (result < INT16_MIN*1.5) {
+            result = INT16_MIN*1.5;
+        }
+
+        return result;
+    }
+}
+
 bool check_key(uint16_t input, size_t idx_in)
 {
     if ((input >> idx_in) & 1) {
@@ -87,7 +149,9 @@ int main(int argc, char **argv)
     log_to_writer(log_writer_stdout, NULL);
 
     struct vigem_sdvxio_config config;
-    get_vigem_sdvxio_config(&config);
+    if (!get_vigem_sdvxio_config(&config)) {
+        exit(EXIT_FAILURE);
+    }
 
     sdvx_io_set_loggers(
         log_impl_misc, log_impl_info, log_impl_warning, log_impl_fatal);
@@ -100,12 +164,14 @@ int main(int argc, char **argv)
     sdvx_io_set_amp_volume(config.amp_volume, config.amp_volume, config.amp_volume);
 
     PVIGEM_CLIENT client = vigem_helper_setup();
+
     if (!client) {
         log_warning("client failed to connect failed");
         return -1;
     }
 
     PVIGEM_TARGET pad = vigem_helper_add_pad(client);
+
     if (!pad) {
         log_warning("vigem_alloc pad 1 failed");
         return -1;
@@ -117,10 +183,14 @@ int main(int argc, char **argv)
     uint16_t gpio0;
     uint16_t gpio1;
     uint16_t vol[2] = {0, 0};
+    uint16_t last_vol[2] = {0, 0};
+
+    int32_t buffered_vol[2] = {0, 0};
 
     XUSB_REPORT state;
 
     log_info("vigem init succeeded, beginning poll loop");
+
     while (loop) {
         sdvx_io_read_input();
 
@@ -133,8 +203,19 @@ int main(int argc, char **argv)
 
         memset(&state, 0, sizeof(state));
 
-        state.sThumbLX = convert_analog_to_s16(vol[0]);
-        state.sThumbRX = convert_analog_to_s16(vol[1]);
+        if (config.relative_analog) {
+            buffered_vol[0] = convert_relative_analog(vol[0], last_vol[0], buffered_vol[0], ANALOG_FIXED_SENSITIVITY);
+            buffered_vol[1] = convert_relative_analog(vol[1], last_vol[1], buffered_vol[1], ANALOG_FIXED_SENSITIVITY);
+
+            state.sThumbLX = filter_floor(buffered_vol[0], ANALOG_FIXED_SENSITIVITY/2);
+            state.sThumbLY = filter_floor(buffered_vol[1], ANALOG_FIXED_SENSITIVITY/2);
+
+            last_vol[0] = vol[0];
+            last_vol[1] = vol[1];
+        } else {
+            state.sThumbLX = convert_analog_to_s16(vol[0]);
+            state.sThumbLY = convert_analog_to_s16(vol[1]);
+        }
 
         state.wButtons |= check_assign_key(
             gpio0, SDVX_IO_IN_GPIO_0_START, XUSB_GAMEPAD_START);

src/main/vigemstub/Module.mk

@@ -5,6 +5,7 @@ cppflags_vigemstub  := \
     -I src/imports \
 
 libs_vigemstub  := \
+    util \
  
 src_vigemstub   := \
     helper.c \

src/main/vigemstub/helper.c

@@ -4,6 +4,7 @@
 
 #include "ViGEm/Client.h"
 
+#include "util/log.h"
 #include "vigemstub/helper.h"
 
 PVIGEM_CLIENT vigem_helper_setup(void)
@@ -11,14 +12,14 @@ PVIGEM_CLIENT vigem_helper_setup(void)
     PVIGEM_CLIENT client = vigem_alloc();
 
     if (client == NULL) {
-        printf("vigem_alloc failed\n");
+        log_warning("vigem_alloc failed\n");
         return NULL;
     }
 
     VIGEM_ERROR retval = vigem_connect(client);
 
     if (!VIGEM_SUCCESS(retval)) {
-        printf("ViGEm Bus connection failed with error code: 0x%x\n", retval);
+        log_warning("ViGEm Bus connection failed with error code: 0x%x\n", retval);
         return NULL;
     }
 
@@ -30,14 +31,14 @@ PVIGEM_TARGET vigem_helper_add_pad(PVIGEM_CLIENT client)
     PVIGEM_TARGET pad = vigem_target_x360_alloc();
 
     if (pad == NULL) {
-        printf("vigem_target_x360_alloc failed\n");
+        log_warning("vigem_target_x360_alloc failed\n");
         return NULL;
     }
 
     VIGEM_ERROR pir = vigem_target_add(client, pad);
 
     if (!VIGEM_SUCCESS(pir)) {
-        printf("Target plugin failed with error code: 0x%x\n", pir);
+        log_warning("Target plugin failed with error code: 0x%x\n", pir);
         return NULL;
     }