fs2open.github.com/code/io/spacemouse.cpp

#include "spacemouse.h"

using namespace io::spacemouse;

#pragma pack(push,1)
struct connexion_3d_old_protocol {
	uint8_t type;
	union {
		struct {
			int16_t trans_x, trans_y, trans_z;
		} type1;
		struct {
			int16_t rot_x, rot_y, rot_z;
		} type2;
		struct {
			uint8_t buttons[4];
		} type3;
	} data;
};

struct connexion_3d_new_protocol {
	uint8_t type;
	union {
		struct {
			int16_t trans_x, trans_y, trans_z;
			int16_t rot_x, rot_y, rot_z;
		} type1;
		struct {
			uint8_t buttons[4];
		} type3;
	} data;
};
#pragma pack(pop)

void SpaceMouse::poll() {
	int bytes_read = 0;
	do {
		//Read until we have all reports, since we need the last one in the buffer for each type as the most up to date one.

		switch (m_definition.protocol) {
		case SpaceMouseDefinition::Protocol::CONNEXION_3D_OLD: {
			static connexion_3d_old_protocol data;

			bytes_read = SDL_hid_read(m_deviceHandle, reinterpret_cast<unsigned char*>(&data), sizeof(connexion_3d_old_protocol));
			if (bytes_read <= 0)
				continue;

			switch (data.type) {
			case 1:
				m_current.translation.xyz.x = static_cast<float>(data.data.type1.trans_x) / 150.0f;
				m_current.translation.xyz.y = static_cast<float>(data.data.type1.trans_y) / -150.0f;
				m_current.translation.xyz.z = static_cast<float>(data.data.type1.trans_z) / -150.0f;
				break;
			case 2:
				m_current.rotation.p = static_cast<float>(data.data.type2.rot_x) / -350.0f;
				m_current.rotation.b = static_cast<float>(data.data.type2.rot_y) / 350.0f;
				m_current.rotation.h = static_cast<float>(data.data.type2.rot_z) / 350.0f;
				break;
			case 3:
				//Buttons are not yet handled
				break;
			default:
				break;
			}
			break;
		}
		case SpaceMouseDefinition::Protocol::CONNEXION_3D_NEW: {
			static connexion_3d_new_protocol data;

			bytes_read = SDL_hid_read(m_deviceHandle, reinterpret_cast<unsigned char*>(&data), sizeof(connexion_3d_new_protocol));
			if (bytes_read <= 0)
				continue;

			switch (data.type) {
			case 1:
				m_current.translation.xyz.x = static_cast<float>(data.data.type1.trans_x) / 150.0f;
				m_current.translation.xyz.y = static_cast<float>(data.data.type1.trans_y) / -150.0f;
				m_current.translation.xyz.z = static_cast<float>(data.data.type1.trans_z) / -150.0f;
				m_current.rotation.p = static_cast<float>(data.data.type1.rot_x) / -350.0f;
				m_current.rotation.b = static_cast<float>(data.data.type1.rot_y) / 350.0f;
				m_current.rotation.h = static_cast<float>(data.data.type1.rot_z) / 350.0f;
				break;
			case 3:
				//Buttons are not yet handled
				break;
			default:
				m_current.translation = ZERO_VECTOR;
				m_current.rotation = ZERO_ANGLES;
				break;
			}
			break;
		}
		default:
			UNREACHABLE("Bad SpaceMouse protocol %d specified!", static_cast<int>(m_definition.protocol));
		}
	} while (bytes_read > 0);
}

void SpaceMouse::pollMaybe() {
	UI_TIMESTAMP now = ui_timestamp();
	if (ui_timestamp_get_delta(m_lastPolled, now) > m_pollingFrequency) {
		m_lastPolled = std::move(now);
		poll();
	}
}

SpaceMouse::SpaceMouse(const SpaceMouseDefinition& definition, SDL_hid_device* deviceHandle, int pollingFrequency)
	: m_definition(definition), m_pollingFrequency(pollingFrequency), m_deviceHandle(deviceHandle),
	  m_current({ ZERO_VECTOR, ZERO_ANGLES }), m_keypresses(definition.buttons, false), m_lastPolled(UI_TIMESTAMP::never()) {
	SDL_hid_set_nonblocking(m_deviceHandle, 1);
}

SpaceMouse::~SpaceMouse() {
	SDL_hid_close(m_deviceHandle);
}

const SpaceMouseMovement& SpaceMouse::getMovement() {
	pollMaybe();
	return m_current;
}

bool SpaceMouse::isButtonPressed(size_t number) {
	if (number >= m_definition.buttons)
		return false;

	pollMaybe();
	return m_keypresses[number];
}

const static SCP_vector<SpaceMouseDefinition> knownSpaceMice {
	SpaceMouseDefinition { 0x046D, 0xC626,  2, SpaceMouseDefinition::Protocol::CONNEXION_3D_OLD }, //SpaceNavigator
	SpaceMouseDefinition { 0x046D, 0xC628,  2, SpaceMouseDefinition::Protocol::CONNEXION_3D_OLD }, //SpaceNavigator
	SpaceMouseDefinition { 0x256F, 0xC635,  2, SpaceMouseDefinition::Protocol::CONNEXION_3D_OLD }, //SpaceMouse Compact
	SpaceMouseDefinition { 0x256F, 0xC62E,  2, SpaceMouseDefinition::Protocol::CONNEXION_3D_NEW }, //SpaceMouse Wireless
	SpaceMouseDefinition { 0x256F, 0xC62F,  2, SpaceMouseDefinition::Protocol::CONNEXION_3D_NEW }, //SpaceMouse Wireless
	SpaceMouseDefinition { 0x256F, 0xC658,  2, SpaceMouseDefinition::Protocol::CONNEXION_3D_NEW }, //SpaceMouse Wireless
	SpaceMouseDefinition { 0x046D, 0xC62B, 15, SpaceMouseDefinition::Protocol::CONNEXION_3D_OLD }, //SpaceMouse Pro
	SpaceMouseDefinition { 0x256F, 0xC631, 15, SpaceMouseDefinition::Protocol::CONNEXION_3D_NEW }, //SpaceMouse Pro Wireless
	SpaceMouseDefinition { 0x256F, 0xC632, 15, SpaceMouseDefinition::Protocol::CONNEXION_3D_NEW }, //SpaceMouse Pro Wireless
	SpaceMouseDefinition { 0x046D, 0xC629, 21, SpaceMouseDefinition::Protocol::CONNEXION_3D_OLD }, //SpacePilot Pro
	SpaceMouseDefinition { 0x256F, 0xC652, 15, SpaceMouseDefinition::Protocol::CONNEXION_3D_NEW }, //3Dconnexion Universal Receiver
};

std::unique_ptr<SpaceMouse> SpaceMouse::searchSpaceMice(int pollingFrequency) {
	std::unique_ptr<SpaceMouse> mouse = nullptr;
	
	auto devices = SDL_hid_enumerate(0, 0);

	for (auto head = devices; head != nullptr && mouse == nullptr; head = head->next) {
		for (const SpaceMouseDefinition& mouseDef : knownSpaceMice) {
			if (mouseDef.vendorID != head->vendor_id || mouseDef.productID != head->product_id)
				continue;

			auto device = SDL_hid_open_path(head->path);

			if (device != nullptr) {
				mouse = std::unique_ptr<SpaceMouse>(new SpaceMouse(mouseDef, device, pollingFrequency));
				break;
			}
		}
	}

	SDL_hid_free_enumeration(devices);

	return mouse;
}

static std::unique_ptr<SpaceMouse> sharedMouse = nullptr;
SpaceMouse* SpaceMouse::getSharedSpaceMouse(int pollingFrequency)
{
	if (!sharedMouse) {
		sharedMouse = searchSpaceMice(pollingFrequency);
	}

	return sharedMouse.get();
}

void SpaceMouse::shutdownSharedSpaceMouse()
{
	sharedMouse = nullptr;
}

#define HANDLE_NONLINEARITY(field, idx) field = copysignf(powf(field, std::get<0>(spacemouse_nonlinearity[idx])) * std::get<1>(spacemouse_nonlinearity[idx]), field)

void SpaceMouseMovement::handleNonlinearities(std::array<std::tuple<float, float>, 6>& spacemouse_nonlinearity) {
	HANDLE_NONLINEARITY(translation.xyz.x, 0);
	HANDLE_NONLINEARITY(translation.xyz.y, 1);
	HANDLE_NONLINEARITY(translation.xyz.z, 2);
	HANDLE_NONLINEARITY(rotation.p, 3);
	HANDLE_NONLINEARITY(rotation.b, 4);
	HANDLE_NONLINEARITY(rotation.h, 5);
}