/**********************************************************************************************
*
* raylib.gestures - Gestures system, gestures processing based on input events (touch/mouse)
*
* NOTE: Memory footprint of this library is aproximately 128 bytes (global variables)
*
* CONFIGURATION:
*
* #define GESTURES_IMPLEMENTATION
* Generates the implementation of the library into the included file.
* If not defined, the library is in header only mode and can be included in other headers
* or source files without problems. But only ONE file should hold the implementation.
*
* #define GESTURES_STANDALONE
* If defined, the library can be used as standalone to process gesture events with
* no external dependencies.
*
* CONTRIBUTORS:
* Marc Palau: Initial implementation (2014)
* Albert Martos: Complete redesign and testing (2015)
* Ian Eito: Complete redesign and testing (2015)
* Ramon Santamaria: Supervision, review, update and maintenance
*
*
* LICENSE: zlib/libpng
*
* Copyright (c) 2014-2021 Ramon Santamaria (@raysan5)
*
* This software is provided "as-is", without any express or implied warranty. In no event
* will the authors be held liable for any damages arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose, including commercial
* applications, and to alter it and redistribute it freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not claim that you
* wrote the original software. If you use this software in a product, an acknowledgment
* in the product documentation would be appreciated but is not required.
*
* 2. Altered source versions must be plainly marked as such, and must not be misrepresented
* as being the original software.
*
* 3. This notice may not be removed or altered from any source distribution.
*
**********************************************************************************************/
#ifndef GESTURES_H
#define GESTURES_H
#ifndef PI
#define PI 3.14159265358979323846
#endif
//----------------------------------------------------------------------------------
// Defines and Macros
//----------------------------------------------------------------------------------
//...
//----------------------------------------------------------------------------------
// Types and Structures Definition
// NOTE: Below types are required for GESTURES_STANDALONE usage
//----------------------------------------------------------------------------------
#if defined(GESTURES_STANDALONE)
#ifndef __cplusplus
// Boolean type
typedef enum { false, true } bool;
#endif
// Vector2 type
typedef struct Vector2 {
float x;
float y;
} Vector2;
// Gestures type
// NOTE: It could be used as flags to enable only some gestures
typedef enum {
GESTURE_NONE = 0,
GESTURE_TAP = 1,
GESTURE_DOUBLETAP = 2,
GESTURE_HOLD = 4,
GESTURE_DRAG = 8,
GESTURE_SWIPE_RIGHT = 16,
GESTURE_SWIPE_LEFT = 32,
GESTURE_SWIPE_UP = 64,
GESTURE_SWIPE_DOWN = 128,
GESTURE_PINCH_IN = 256,
GESTURE_PINCH_OUT = 512
} Gestures;
#endif
typedef enum { TOUCH_UP, TOUCH_DOWN, TOUCH_MOVE } TouchAction;
// Gesture events
// NOTE: MAX_TOUCH_POINTS fixed to 4
typedef struct {
int touchAction;
int pointCount;
int pointerId[4];
Vector2 position[4];
} GestureEvent;
#ifdef __cplusplus
extern "C" { // Prevents name mangling of functions
#endif
//----------------------------------------------------------------------------------
// Global Variables Definition
//----------------------------------------------------------------------------------
//...
//----------------------------------------------------------------------------------
// Module Functions Declaration
//----------------------------------------------------------------------------------
void ProcessGestureEvent(GestureEvent event); // Process gesture event and translate it into gestures
void UpdateGestures(void); // Update gestures detected (must be called every frame)
#if defined(GESTURES_STANDALONE)
void SetGesturesEnabled(unsigned int gestureFlags); // Enable a set of gestures using flags
bool IsGestureDetected(int gesture); // Check if a gesture have been detected
int GetGestureDetected(void); // Get latest detected gesture
int GetTouchPointsCount(void); // Get touch points count
float GetGestureHoldDuration(void); // Get gesture hold time in milliseconds
Vector2 GetGestureDragVector(void); // Get gesture drag vector
float GetGestureDragAngle(void); // Get gesture drag angle
Vector2 GetGesturePinchVector(void); // Get gesture pinch delta
float GetGesturePinchAngle(void); // Get gesture pinch angle
#endif
#ifdef __cplusplus
}
#endif
#endif // GESTURES_H
/***********************************************************************************
*
* GESTURES IMPLEMENTATION
*
************************************************************************************/
#if defined(GESTURES_IMPLEMENTATION)
#if defined(_WIN32)
// Functions required to query time on Windows
int __stdcall QueryPerformanceCounter(unsigned long long int *lpPerformanceCount);
int __stdcall QueryPerformanceFrequency(unsigned long long int *lpFrequency);
#elif defined(__linux__)
#if _POSIX_C_SOURCE < 199309L
#undef _POSIX_C_SOURCE
#define _POSIX_C_SOURCE 199309L // Required for CLOCK_MONOTONIC if compiled with c99 without gnu ext.
#endif
#include <sys/time.h> // Required for: timespec
#include <time.h> // Required for: clock_gettime()
#include <math.h> // Required for: sqrtf(), atan2f()
#endif
#if defined(__APPLE__) // macOS also defines __MACH__
#include <mach/clock.h> // Required for: clock_get_time()
#include <mach/mach.h> // Required for: mach_timespec_t
#endif
//----------------------------------------------------------------------------------
// Defines and Macros
//----------------------------------------------------------------------------------
#define FORCE_TO_SWIPE 0.0005f // Swipe force, measured in normalized screen units/time
#define MINIMUM_DRAG 0.015f // Drag minimum force, measured in normalized screen units (0.0f to 1.0f)
#define MINIMUM_PINCH 0.005f // Pinch minimum force, measured in normalized screen units (0.0f to 1.0f)
#define TAP_TIMEOUT 300 // Tap minimum time, measured in milliseconds
#define PINCH_TIMEOUT 300 // Pinch minimum time, measured in milliseconds
#define DOUBLETAP_RANGE 0.03f // DoubleTap range, measured in normalized screen units (0.0f to 1.0f)
//----------------------------------------------------------------------------------
// Types and Structures Definition
//----------------------------------------------------------------------------------
// Gestures module state context [136 bytes]
typedef struct {
unsigned int current; // Current detected gesture
unsigned int enabledFlags; // Enabled gestures flags
struct {
int firstId; // Touch id for first touch point
int pointCount; // Touch points counter
double eventTime; // Time stamp when an event happened
Vector2 upPosition; // Touch up position
Vector2 downPositionA; // First touch down position
Vector2 downPositionB; // Second touch down position
Vector2 downDragPosition; // Touch drag position
Vector2 moveDownPositionA; // First touch down position on move
Vector2 moveDownPositionB; // Second touch down position on move
int tapCounter; // TAP counter (one tap implies TOUCH_DOWN and TOUCH_UP actions)
} Touch;
struct {
bool resetRequired; // HOLD reset to get first touch point again
double timeDuration; // HOLD duration in milliseconds
} Hold;
struct {
Vector2 vector; // DRAG vector (between initial and current position)
float angle; // DRAG angle (relative to x-axis)
float distance; // DRAG distance (from initial touch point to final) (normalized [0..1])
float intensity; // DRAG intensity, how far why did the DRAG (pixels per frame)
} Drag;
struct {
bool start; // SWIPE used to define when start measuring GESTURES.Swipe.timeDuration
double timeDuration; // SWIPE time to calculate drag intensity
} Swipe;
struct {
Vector2 vector; // PINCH vector (between first and second touch points)
float angle; // PINCH angle (relative to x-axis)
float distance; // PINCH displacement distance (normalized [0..1])
} Pinch;
} GesturesData;
//----------------------------------------------------------------------------------
// Global Variables Definition
//----------------------------------------------------------------------------------
static GesturesData GESTURES = {
.Touch.firstId = -1,
.current = GESTURE_NONE, // No current gesture detected
.enabledFlags = 0b0000001111111111 // All gestures supported by default
};
//----------------------------------------------------------------------------------
// Module specific Functions Declaration
//----------------------------------------------------------------------------------
#if defined(GESTURES_STANDALONE)
// Some required math functions provided by raymath.h
static float Vector2Angle(Vector2 initialPosition, Vector2 finalPosition);
static float Vector2Distance(Vector2 v1, Vector2 v2);
#endif
static double GetCurrentTime(void);
//----------------------------------------------------------------------------------
// Module Functions Definition
//----------------------------------------------------------------------------------
// Enable only desired getures to be detected
void SetGesturesEnabled(unsigned int gestureFlags)
{
GESTURES.enabledFlags = gestureFlags;
}
// Check if a gesture have been detected
bool IsGestureDetected(int gesture)
{
if ((GESTURES.enabledFlags & GESTURES.current) == gesture) return true;
else return false;
}
// Process gesture event and translate it into gestures
void ProcessGestureEvent(GestureEvent event)
{
// Reset required variables
GESTURES.Touch.pointCount = event.pointCount; // Required on UpdateGestures()
if (GESTURES.Touch.pointCount < 2)
{
if (event.touchAction == TOUCH_DOWN)
{
GESTURES.Touch.tapCounter++; // Tap counter
// Detect GESTURE_DOUBLE_TAP
if ((GESTURES.current == GESTURE_NONE) && (GESTURES.Touch.tapCounter >= 2) && ((GetCurrentTime() - GESTURES.Touch.eventTime) < TAP_TIMEOUT) && (Vector2Distance(GESTURES.Touch.downPositionA, event.position[0]) < DOUBLETAP_RANGE))
{
GESTURES.current = GESTURE_DOUBLETAP;
GESTURES.Touch.tapCounter = 0;
}
else // Detect GESTURE_TAP
{
GESTURES.Touch.tapCounter = 1;
GESTURES.current = GESTURE_TAP;
}
GESTURES.Touch.downPositionA = event.position[0];
GESTURES.Touch.downDragPosition = event.position[0];
GESTURES.Touch.upPosition = GESTURES.Touch.downPositionA;
GESTURES.Touch.eventTime = GetCurrentTime();
GESTURES.Touch.firstId = event.pointerId[0];
GESTURES.Drag.vector = (Vector2){ 0.0f, 0.0f };
}
else if (event.touchAction == TOUCH_UP)
{
if (GESTURES.current == GESTURE_DRAG) GESTURES.Touch.upPosition = event.position[0];
// NOTE: GESTURES.Drag.intensity dependend on the resolution of the screen
GESTURES.Drag.distance = Vector2Distance(GESTURES.Touch.downPositionA, GESTURES.Touch.upPosition);
GESTURES.Drag.intensity = GESTURES.Drag.distance/(float)((GetCurrentTime() - GESTURES.Swipe.timeDuration));
GESTURES.Swipe.start = false;
// Detect GESTURE_SWIPE
if ((GESTURES.Drag.intensity > FORCE_TO_SWIPE) && (GESTURES.Touch.firstId == event.pointerId[0]))
{
// NOTE: Angle should be inverted in Y
GESTURES.Drag.angle = 360.0f - Vector2Angle(GESTURES.Touch.downPositionA, GESTURES.Touch.upPosition);
if ((GESTURES.Drag.angle < 30) || (GESTURES.Drag.angle > 330)) GESTURES.current = GESTURE_SWIPE_RIGHT; // Right
else if ((GESTURES.Drag.angle > 30) && (GESTURES.Drag.angle < 120)) GESTURES.current = GESTURE_SWIPE_UP; // Up
else if ((GESTURES.Drag.angle > 120) && (GESTURES.Drag.angle < 210)) GESTURES.current = GESTURE_SWIPE_LEFT; // Left
else if ((GESTURES.Drag.angle > 210) && (GESTURES.Drag.angle < 300)) GESTURES.current = GESTURE_SWIPE_DOWN; // Down
else GESTURES.current = GESTURE_NONE;
}
else
{
GESTURES.Drag.distance = 0.0f;
GESTURES.Drag.intensity = 0.0f;
GESTURES.Drag.angle = 0.0f;
GESTURES.current = GESTURE_NONE;
}
GESTURES.Touch.downDragPosition = (Vector2){ 0.0f, 0.0f };
GESTURES.Touch.pointCount = 0;
}
else if (event.touchAction == TOUCH_MOVE)
{
if (GESTURES.current == GESTURE_DRAG) GESTURES.Touch.eventTime = GetCurrentTime();
if (!GESTURES.Swipe.start)
{
GESTURES.Swipe.timeDuration = GetCurrentTime();
GESTURES.Swipe.start = true;
}
GESTURES.Touch.moveDownPositionA = event.position[0];
if (GESTURES.current == GESTURE_HOLD)
{
if (GESTURES.Hold.resetRequired) GESTURES.Touch.downPositionA = event.position[0];
GESTURES.Hold.resetRequired = false;
// Detect GESTURE_DRAG
if (Vector2Distance(GESTURES.Touch.downPositionA, GESTURES.Touch.moveDownPositionA) >= MINIMUM_DRAG)
{
GESTURES.Touch.eventTime = GetCurrentTime();
GESTURES.current = GESTURE_DRAG;
}
}
GESTURES.Drag.vector.x = GESTURES.Touch.moveDownPositionA.x - GESTURES.Touch.downDragPosition.x;
GESTURES.Drag.vector.y = GESTURES.Touch.moveDownPositionA.y - GESTURES.Touch.downDragPosition.y;
}
}
else // Two touch points
{
if (event.touchAction == TOUCH_DOWN)
{
GESTURES.Touch.downPositionA = event.position[0];
GESTURES.Touch.downPositionB = event.position[1];
//GESTURES.Pinch.distance = Vector2Distance(GESTURES.Touch.downPositionA, GESTURES.Touch.downPositionB);
GESTURES.Pinch.vector.x = GESTURES.Touch.downPositionB.x - GESTURES.Touch.downPositionA.x;
GESTURES.Pinch.vector.y = GESTURES.Touch.downPositionB.y - GESTURES.Touch.downPositionA.y;
GESTURES.current = GESTURE_HOLD;
GESTURES.Hold.timeDuration = GetCurrentTime();
}
else if (event.touchAction == TOUCH_MOVE)
{
GESTURES.Pinch.distance = Vector2Distance(GESTURES.Touch.moveDownPositionA, GESTURES.Touch.moveDownPositionB);
GESTURES.Touch.downPositionA = GESTURES.Touch.moveDownPositionA;
GESTURES.Touch.downPositionB = GESTURES.Touch.moveDownPositionB;
GESTURES.Touch.moveDownPositionA = event.position[0];
GESTURES.Touch.moveDownPositionB = event.position[1];
GESTURES.Pinch.vector.x = GESTURES.Touch.moveDownPositionB.x - GESTURES.Touch.moveDownPositionA.x;
GESTURES.Pinch.vector.y = GESTURES.Touch.moveDownPositionB.y - GESTURES.Touch.moveDownPositionA.y;
if ((Vector2Distance(GESTURES.Touch.downPositionA, GESTURES.Touch.moveDownPositionA) >= MINIMUM_PINCH) || (Vector2Distance(GESTURES.Touch.downPositionB, GESTURES.Touch.moveDownPositionB) >= MINIMUM_PINCH))
{
if ((Vector2Distance(GESTURES.Touch.moveDownPositionA, GESTURES.Touch.moveDownPositionB) - GESTURES.Pinch.distance) < 0) GESTURES.current = GESTURE_PINCH_IN;
else GESTURES.current = GESTURE_PINCH_OUT;
}
else
{
GESTURES.current = GESTURE_HOLD;
GESTURES.Hold.timeDuration = GetCurrentTime();
}
// NOTE: Angle should be inverted in Y
GESTURES.Pinch.angle = 360.0f - Vector2Angle(GESTURES.Touch.moveDownPositionA, GESTURES.Touch.moveDownPositionB);
}
else if (event.touchAction == TOUCH_UP)
{
GESTURES.Pinch.distance = 0.0f;
GESTURES.Pinch.angle = 0.0f;
GESTURES.Pinch.vector = (Vector2){ 0.0f, 0.0f };
GESTURES.Touch.pointCount = 0;
GESTURES.current = GESTURE_NONE;
}
}
}
// Update gestures detected (must be called every frame)
void UpdateGestures(void)
{
// NOTE: Gestures are processed through system callbacks on touch events
// Detect GESTURE_HOLD
if (((GESTURES.current == GESTURE_TAP) || (GESTURES.current == GESTURE_DOUBLETAP)) && (GESTURES.Touch.pointCount < 2))
{
GESTURES.current = GESTURE_HOLD;
GESTURES.Hold.timeDuration = GetCurrentTime();
}
if (((GetCurrentTime() - GESTURES.Touch.eventTime) > TAP_TIMEOUT) && (GESTURES.current == GESTURE_DRAG) && (GESTURES.Touch.pointCount < 2))
{
GESTURES.current = GESTURE_HOLD;
GESTURES.Hold.timeDuration = GetCurrentTime();
GESTURES.Hold.resetRequired = true;
}
// Detect GESTURE_NONE
if ((GESTURES.current == GESTURE_SWIPE_RIGHT) || (GESTURES.current == GESTURE_SWIPE_UP) || (GESTURES.current == GESTURE_SWIPE_LEFT) || (GESTURES.current == GESTURE_SWIPE_DOWN))
{
GESTURES.current = GESTURE_NONE;
}
}
// Get number of touch points
int GetTouchPointsCount(void)
{
// NOTE: point count is calculated when ProcessGestureEvent(GestureEvent event) is called
return GESTURES.Touch.pointCount;
}
// Get latest detected gesture
int GetGestureDetected(void)
{
// Get current gesture only if enabled
return (GESTURES.enabledFlags & GESTURES.current);
}
// Hold time measured in ms
float GetGestureHoldDuration(void)
{
// NOTE: time is calculated on current gesture HOLD
double time = 0.0;
if (GESTURES.current == GESTURE_HOLD) time = GetCurrentTime() - GESTURES.Hold.timeDuration;
return (float)time;
}
// Get drag vector (between initial touch point to current)
Vector2 GetGestureDragVector(void)
{
// NOTE: drag vector is calculated on one touch points TOUCH_MOVE
return GESTURES.Drag.vector;
}
// Get drag angle
// NOTE: Angle in degrees, horizontal-right is 0, counterclock-wise
float GetGestureDragAngle(void)
{
// NOTE: drag angle is calculated on one touch points TOUCH_UP
return GESTURES.Drag.angle;
}
// Get distance between two pinch points
Vector2 GetGesturePinchVector(void)
{
// NOTE: The position values used for GESTURES.Pinch.distance are not modified like the position values of [core.c]-->GetTouchPosition(int index)
// NOTE: pinch distance is calculated on two touch points TOUCH_MOVE
return GESTURES.Pinch.vector;
}
// Get angle beween two pinch points
// NOTE: Angle in degrees, horizontal-right is 0, counterclock-wise
float GetGesturePinchAngle(void)
{
// NOTE: pinch angle is calculated on two touch points TOUCH_MOVE
return GESTURES.Pinch.angle;
}
//----------------------------------------------------------------------------------
// Module specific Functions Definition
//----------------------------------------------------------------------------------
#if defined(GESTURES_STANDALONE)
// Returns angle from two-points vector with X-axis
static float Vector2Angle(Vector2 v1, Vector2 v2)
{
float angle = atan2f(v2.y - v1.y, v2.x - v1.x)*(180.0f/PI);
if (angle < 0) angle += 360.0f;
return angle;
}
// Calculate distance between two Vector2
static float Vector2Distance(Vector2 v1, Vector2 v2)
{
float result;
float dx = v2.x - v1.x;
float dy = v2.y - v1.y;
result = (float)sqrt(dx*dx + dy*dy);
return result;
}
#endif
// Time measure returned are milliseconds
static double GetCurrentTime(void)
{
double time = 0;
#if defined(_WIN32)
unsigned long long int clockFrequency, currentTime;
QueryPerformanceFrequency(&clockFrequency); // BE CAREFUL: Costly operation!
QueryPerformanceCounter(¤tTime);
time = (double)currentTime/clockFrequency*1000.0f; // Time in miliseconds
#endif
#if defined(__linux__)
// NOTE: Only for Linux-based systems
struct timespec now;
clock_gettime(CLOCK_MONOTONIC, &now);
unsigned long long int nowTime = (unsigned long long int)now.tv_sec*1000000000LLU + (unsigned long long int)now.tv_nsec; // Time in nanoseconds
time = ((double)nowTime/1000000.0); // Time in miliseconds
#endif
#if defined(__APPLE__)
//#define CLOCK_REALTIME CALENDAR_CLOCK // returns UTC time since 1970-01-01
//#define CLOCK_MONOTONIC SYSTEM_CLOCK // returns the time since boot time
clock_serv_t cclock;
mach_timespec_t now;
host_get_clock_service(mach_host_self(), SYSTEM_CLOCK, &cclock);
// NOTE: OS X does not have clock_gettime(), using clock_get_time()
clock_get_time(cclock, &now);
mach_port_deallocate(mach_task_self(), cclock);
unsigned long long int nowTime = (unsigned long long int)now.tv_sec*1000000000LLU + (unsigned long long int)now.tv_nsec; // Time in nanoseconds
time = ((double)nowTime/1000000.0); // Time in miliseconds
#endif
return time;
}
#endif // GESTURES_IMPLEMENTATION