/********************************************************************************************** * * raylib Gestures System - Gestures Processing based on input gesture events (touch/mouse) * * #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. * * NOTE: Memory footprint of this library is aproximately 128 bytes * * Initial design by Marc Palau (2014) * Redesigned by Albert Martos and Ian Eito (2015) * Reviewed by Ramon Santamaria (2015-2016) * * 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) #include // Required for: atan2(), sqrt() #include // Required for: uint64_t #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) #include // Required for: timespec #include // Required for: clock_gettime() #endif //---------------------------------------------------------------------------------- // Defines and Macros //---------------------------------------------------------------------------------- #define FORCE_TO_SWIPE 0.0005f // Measured in normalized screen units/time #define MINIMUM_DRAG 0.015f // Measured in normalized screen units (0.0f to 1.0f) #define MINIMUM_PINCH 0.005f // Measured in normalized screen units (0.0f to 1.0f) #define TAP_TIMEOUT 300 // Time in milliseconds #define PINCH_TIMEOUT 300 // Time in milliseconds #define DOUBLETAP_RANGE 0.03f // Measured in normalized screen units (0.0f to 1.0f) //---------------------------------------------------------------------------------- // Types and Structures Definition //---------------------------------------------------------------------------------- // ... //---------------------------------------------------------------------------------- // Global Variables Definition //---------------------------------------------------------------------------------- // Touch gesture variables static Vector2 touchDownPosition = { 0.0f, 0.0f }; static Vector2 touchDownPosition2 = { 0.0f, 0.0f }; static Vector2 touchDownDragPosition = { 0.0f, 0.0f }; static Vector2 touchUpPosition = { 0.0f, 0.0f }; static Vector2 moveDownPosition = { 0.0f, 0.0f }; static Vector2 moveDownPosition2 = { 0.0f, 0.0f }; static int pointCount = 0; // Touch points counter static int firstTouchId = -1; // Touch id for first touch point static double eventTime = 0.0; // Time stamp when an event happened // Tap gesture variables static int tapCounter = 0; // TAP counter (one tap implies TOUCH_DOWN and TOUCH_UP actions) // Hold gesture variables static bool resetHold = false; // HOLD reset to get first touch point again static double timeHold = 0.0f; // HOLD duration in milliseconds // Drag gesture variables static Vector2 dragVector = { 0.0f , 0.0f }; // DRAG vector (between initial and current position) static float dragAngle = 0.0f; // DRAG angle (relative to x-axis) static float dragDistance = 0.0f; // DRAG distance (from initial touch point to final) (normalized [0..1]) static float dragIntensity = 0.0f; // DRAG intensity, how far why did the DRAG (pixels per frame) // Swipe gestures variables static bool startMoving = false; // SWIPE used to define when start measuring swipeTime static double swipeTime = 0.0; // SWIPE time to calculate drag intensity // Pinch gesture variables static Vector2 pinchVector = { 0.0f , 0.0f }; // PINCH vector (between first and second touch points) static float pinchAngle = 0.0f; // PINCH angle (relative to x-axis) static float pinchDistance = 0.0f; // PINCH displacement distance (normalized [0..1]) static int currentGesture = GESTURE_NONE; // Current detected gesture // Enabled gestures flags, all gestures enabled by default static unsigned int enabledGestures = 0b0000001111111111; //---------------------------------------------------------------------------------- // Module specific Functions Declaration //---------------------------------------------------------------------------------- static float Vector2Angle(Vector2 initialPosition, Vector2 finalPosition); static float Vector2Distance(Vector2 v1, Vector2 v2); static double GetCurrentTime(void); //---------------------------------------------------------------------------------- // Module Functions Definition //---------------------------------------------------------------------------------- // Enable only desired getures to be detected void SetGesturesEnabled(unsigned int gestureFlags) { enabledGestures = gestureFlags; } // Check if a gesture have been detected bool IsGestureDetected(int gesture) { if ((enabledGestures & currentGesture) == gesture) return true; else return false; } // Process gesture event and translate it into gestures void ProcessGestureEvent(GestureEvent event) { // Reset required variables pointCount = event.pointCount; // Required on UpdateGestures() if (pointCount < 2) { if (event.touchAction == TOUCH_DOWN) { tapCounter++; // Tap counter // Detect GESTURE_DOUBLE_TAP if ((currentGesture == GESTURE_NONE) && (tapCounter >= 2) && ((GetCurrentTime() - eventTime) < TAP_TIMEOUT) && (Vector2Distance(touchDownPosition, event.position[0]) < DOUBLETAP_RANGE)) { currentGesture = GESTURE_DOUBLETAP; tapCounter = 0; } else // Detect GESTURE_TAP { tapCounter = 1; currentGesture = GESTURE_TAP; } touchDownPosition = event.position[0]; touchDownDragPosition = event.position[0]; touchUpPosition = touchDownPosition; eventTime = GetCurrentTime(); firstTouchId = event.pointerId[0]; dragVector = (Vector2){ 0.0f, 0.0f }; } else if (event.touchAction == TOUCH_UP) { if (currentGesture == GESTURE_DRAG) touchUpPosition = event.position[0]; // NOTE: dragIntensity dependend on the resolution of the screen dragDistance = Vector2Distance(touchDownPosition, touchUpPosition); dragIntensity = dragDistance/(float)((GetCurrentTime() - swipeTime)); startMoving = false; // Detect GESTURE_SWIPE if ((dragIntensity > FORCE_TO_SWIPE) && (firstTouchId == event.pointerId[0])) { // NOTE: Angle should be inverted in Y dragAngle = 360.0f - Vector2Angle(touchDownPosition, touchUpPosition); if ((dragAngle < 30) || (dragAngle > 330)) currentGesture = GESTURE_SWIPE_RIGHT; // Right else if ((dragAngle > 30) && (dragAngle < 120)) currentGesture = GESTURE_SWIPE_UP; // Up else if ((dragAngle > 120) && (dragAngle < 210)) currentGesture = GESTURE_SWIPE_LEFT; // Left else if ((dragAngle > 210) && (dragAngle < 300)) currentGesture = GESTURE_SWIPE_DOWN; // Down else currentGesture = GESTURE_NONE; } else { dragDistance = 0.0f; dragIntensity = 0.0f; dragAngle = 0.0f; currentGesture = GESTURE_NONE; } touchDownDragPosition = (Vector2){ 0.0f, 0.0f }; pointCount = 0; } else if (event.touchAction == TOUCH_MOVE) { if (currentGesture == GESTURE_DRAG) eventTime = GetCurrentTime(); if (!startMoving) { swipeTime = GetCurrentTime(); startMoving = true; } moveDownPosition = event.position[0]; if (currentGesture == GESTURE_HOLD) { if (resetHold) touchDownPosition = event.position[0]; resetHold = false; // Detect GESTURE_DRAG if (Vector2Distance(touchDownPosition, moveDownPosition) >= MINIMUM_DRAG) { eventTime = GetCurrentTime(); currentGesture = GESTURE_DRAG; } } dragVector.x = moveDownPosition.x - touchDownDragPosition.x; dragVector.y = moveDownPosition.y - touchDownDragPosition.y; } } else // Two touch points { if (event.touchAction == TOUCH_DOWN) { touchDownPosition = event.position[0]; touchDownPosition2 = event.position[1]; //pinchDistance = Vector2Distance(touchDownPosition, touchDownPosition2); pinchVector.x = touchDownPosition2.x - touchDownPosition.x; pinchVector.y = touchDownPosition2.y - touchDownPosition.y; currentGesture = GESTURE_HOLD; timeHold = GetCurrentTime(); } else if (event.touchAction == TOUCH_MOVE) { pinchDistance = Vector2Distance(moveDownPosition, moveDownPosition2); touchDownPosition = moveDownPosition; touchDownPosition2 = moveDownPosition2; moveDownPosition = event.position[0]; moveDownPosition2 = event.position[1]; pinchVector.x = moveDownPosition2.x - moveDownPosition.x; pinchVector.y = moveDownPosition2.y - moveDownPosition.y; if ((Vector2Distance(touchDownPosition, moveDownPosition) >= MINIMUM_PINCH) || (Vector2Distance(touchDownPosition2, moveDownPosition2) >= MINIMUM_PINCH)) { if ((Vector2Distance(moveDownPosition, moveDownPosition2) - pinchDistance) < 0) currentGesture = GESTURE_PINCH_IN; else currentGesture = GESTURE_PINCH_OUT; } else { currentGesture = GESTURE_HOLD; timeHold = GetCurrentTime(); } // NOTE: Angle should be inverted in Y pinchAngle = 360.0f - Vector2Angle(moveDownPosition, moveDownPosition2); } else if (event.touchAction == TOUCH_UP) { pinchDistance = 0.0f; pinchAngle = 0.0f; pinchVector = (Vector2){ 0.0f, 0.0f }; pointCount = 0; currentGesture = 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 (((currentGesture == GESTURE_TAP) || (currentGesture == GESTURE_DOUBLETAP)) && (pointCount < 2)) { currentGesture = GESTURE_HOLD; timeHold = GetCurrentTime(); } if (((GetCurrentTime() - eventTime) > TAP_TIMEOUT) && (currentGesture == GESTURE_DRAG) && (pointCount < 2)) { currentGesture = GESTURE_HOLD; timeHold = GetCurrentTime(); resetHold = true; } // Detect GESTURE_NONE if ((currentGesture == GESTURE_SWIPE_RIGHT) || (currentGesture == GESTURE_SWIPE_UP) || (currentGesture == GESTURE_SWIPE_LEFT) || (currentGesture == GESTURE_SWIPE_DOWN)) { currentGesture = GESTURE_NONE; } } // Get number of touch points int GetTouchPointsCount(void) { // NOTE: point count is calculated when ProcessGestureEvent(GestureEvent event) is called return pointCount; } // Get latest detected gesture int GetGestureDetected(void) { // Get current gesture only if enabled return (enabledGestures & currentGesture); } // Hold time measured in ms float GetGestureHoldDuration(void) { // NOTE: time is calculated on current gesture HOLD double time = 0.0; if (currentGesture == GESTURE_HOLD) time = GetCurrentTime() - timeHold; 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 dragVector; } // 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 dragAngle; } // Get distance between two pinch points Vector2 GetGesturePinchVector(void) { // NOTE: The position values used for pinchDistance 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 pinchVector; } // 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 pinchAngle; } //---------------------------------------------------------------------------------- // Module specific Functions Definition //---------------------------------------------------------------------------------- // Returns angle from two-points vector with X-axis static float Vector2Angle(Vector2 initialPosition, Vector2 finalPosition) { float angle; angle = atan2f(finalPosition.y - initialPosition.y, finalPosition.x - initialPosition.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; } // Time measure returned are milliseconds static double GetCurrentTime(void) { double time = 0; #if defined(_WIN32) unsigned long long int clockFrequency, currentTime; QueryPerformanceFrequency(&clockFrequency); 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); uint64_t nowTime = (uint64_t)now.tv_sec*1000000000LLU + (uint64_t)now.tv_nsec; // Time in nanoseconds time = ((double)nowTime/1000000.0); // Time in miliseconds #endif return time; } #endif // GESTURES_IMPLEMENTATION