Merge 7999bbafa8 into 27ba7de1e4

examples/physics_basic_rigidbody.c

@@ -13,10 +13,13 @@
 
 #define PHYSAC_IMPLEMENTATION
 #include "physac.h"
+#include <pthread.h>
 
 #define MOVE_VELOCITY    5
 #define JUMP_VELOCITY    30
 
+void* PhysicsThread(void *arg);
+
 int main()
 {
     // Initialization
@@ -53,6 +56,10 @@ int main()
     // Create pplatform physic object
     PhysicBody platform = CreatePhysicBody((Vector2){ screenWidth/2, screenHeight*0.7f }, 0.0f, (Vector2){ screenWidth*0.25f, 20 });
     
+    // Create physics thread
+    pthread_t tid;
+    pthread_create(&tid, NULL, &PhysicsThread, NULL);
+    
     SetTargetFPS(60);
     //--------------------------------------------------------------------------------------
 
@@ -61,10 +68,9 @@ int main()
     {
         // Update
         //----------------------------------------------------------------------------------
-        UpdatePhysics();    // Update all created physic objects
         
         // Check rectangle movement inputs
-        if (IsKeyDown('W') && rectangle->rigidbody.isGrounded) rectangle->rigidbody.velocity.y = JUMP_VELOCITY;
+        if (IsKeyPressed('W')) rectangle->rigidbody.velocity.y = JUMP_VELOCITY;
         if (IsKeyDown('A')) rectangle->rigidbody.velocity.x = -MOVE_VELOCITY;
         else if (IsKeyDown('D')) rectangle->rigidbody.velocity.x = MOVE_VELOCITY;
         
@@ -117,6 +123,8 @@ int main()
 
     // De-Initialization
     //--------------------------------------------------------------------------------------
+    pthread_cancel(tid);    // Destroy physics thread
+    
     ClosePhysics();       // Unitialize physics (including all loaded objects)
     
     CloseWindow();        // Close window and OpenGL context
@@ -124,3 +132,23 @@ int main()
 
     return 0;
 }
+
+void* PhysicsThread(void *arg)
+{
+    // Initialize time variables
+    double currentTime = GetTime();
+    double previousTime = currentTime;
+    
+    // Physics update loop
+    while (!WindowShouldClose()) 
+    {
+        currentTime = GetTime();
+        double deltaTime = (double)(currentTime - previousTime);
+        previousTime = currentTime;
+
+        // Delta time value needs to be inverse multiplied by physics time step value (1/target fps)
+        UpdatePhysics(deltaTime/PHYSICS_TIMESTEP);
+    }
+    
+    return NULL;
+}

examples/physics_forces.c

@@ -13,12 +13,15 @@
 
 #define PHYSAC_IMPLEMENTATION
 #include "physac.h"
+#include <pthread.h>
 
 #define FORCE_AMOUNT        5.0f
 #define FORCE_RADIUS        150
 #define LINE_LENGTH         75
 #define TRIANGLE_LENGTH     12
 
+void* PhysicsThread(void *arg);
+
 int main()
 {
     // Initialization
@@ -61,6 +64,10 @@ int main()
     PhysicBody topWall = CreatePhysicBody((Vector2){ screenWidth/2, -25 }, 0.0f, (Vector2){ screenWidth, 50 });
     PhysicBody bottomWall = CreatePhysicBody((Vector2){ screenWidth/2, screenHeight + 25 }, 0.0f, (Vector2){ screenWidth, 50 });
     
+    // Create physics thread
+    pthread_t tid;
+    pthread_create(&tid, NULL, &PhysicsThread, NULL);
+    
     SetTargetFPS(60);
     //--------------------------------------------------------------------------------------
 
@@ -69,7 +76,6 @@ int main()
     {
         // Update
         //----------------------------------------------------------------------------------
-        UpdatePhysics();    // Update all created physic objects
         
         // Update mouse position value
         mousePosition = GetMousePosition();
@@ -174,6 +180,8 @@ int main()
 
     // De-Initialization
     //--------------------------------------------------------------------------------------
+    pthread_cancel(tid);    // Destroy physics thread
+    
     ClosePhysics();       // Unitialize physics module
     
     CloseWindow();        // Close window and OpenGL context
@@ -181,3 +189,23 @@ int main()
 
     return 0;
 }
+
+void* PhysicsThread(void *arg)
+{
+    // Initialize time variables
+    double currentTime = GetTime();
+    double previousTime = currentTime;
+    
+    // Physics update loop
+    while (!WindowShouldClose()) 
+    {
+        currentTime = GetTime();
+        double deltaTime = (double)(currentTime - previousTime);
+        previousTime = currentTime;
+
+        // Delta time value needs to be inverse multiplied by physics time step value (1/target fps)
+        UpdatePhysics(deltaTime/PHYSICS_TIMESTEP);
+    }
+    
+    return NULL;
+}

src/core.c

@@ -290,7 +290,6 @@ static void InitDisplay(int width, int height);         // Initialize display de
 static void InitGraphics(void);                         // Initialize OpenGL graphics
 static void SetupFramebufferSize(int displayWidth, int displayHeight);
 static void InitTimer(void);                            // Initialize timer
-static double GetTime(void);                            // Returns time since InitTimer() was run
 static bool GetKeyStatus(int key);                      // Returns if a key has been pressed
 static bool GetMouseButtonStatus(int button);           // Returns if a mouse button has been pressed
 static void PollInputEvents(void);                      // Register user events
@@ -2039,7 +2038,7 @@ static void InitTimer(void)
 }
 
 // Get current time measure (in seconds) since InitTimer()
-static double GetTime(void)
+double GetTime(void)
 {
 #if defined(PLATFORM_DESKTOP) || defined(PLATFORM_WEB)
     return glfwGetTime();

src/physac.h

@@ -146,7 +146,7 @@ typedef struct PhysicBodyData {
 // Module Functions Declaration
 //----------------------------------------------------------------------------------
 PHYSACDEF void InitPhysics(Vector2 gravity);                                            // Initializes pointers array (just pointers, fixed size)
-PHYSACDEF void UpdatePhysics();                                                         // Update physic objects, calculating physic behaviours and collisions detection
+PHYSACDEF void UpdatePhysics(double deltaTime);                                         // Update physic objects, calculating physic behaviours and collisions detection
 PHYSACDEF void ClosePhysics();                                                          // Unitialize all physic objects and empty the objects pool
 
 PHYSACDEF PhysicBody CreatePhysicBody(Vector2 position, float rotation, Vector2 scale); // Create a new physic body dinamically, initialize it and add to pool
@@ -182,7 +182,7 @@ PHYSACDEF Rectangle TransformToRectangle(Transform transform);
 // Defines and Macros
 //----------------------------------------------------------------------------------
 #define MAX_PHYSIC_BODIES       256             // Maximum available physic bodies slots in bodies pool
-#define PHYSICS_STEPS            64             // Physics update steps per frame for improved collision-detection
+#define PHYSICS_TIMESTEP        0.016666        // Physics fixed time step (1/fps)
 #define PHYSICS_ACCURACY        0.0001f         // Velocity subtract operations round filter (friction)
 #define PHYSICS_ERRORPERCENT    0.001f          // Collision resolve position fix
 
@@ -218,12 +218,7 @@ PHYSACDEF void InitPhysics(Vector2 gravity)
 }
 
 // Update physic objects, calculating physic behaviours and collisions detection
-PHYSACDEF void UpdatePhysics()
+PHYSACDEF void UpdatePhysics(double deltaTime)
-{
-    // Reset all physic objects is grounded state
-    for (int i = 0; i < physicBodiesCount; i++) physicBodies[i]->rigidbody.isGrounded = false;
-    
-    for (int steps = 0; steps < PHYSICS_STEPS; steps++)
 {
     for (int i = 0; i < physicBodiesCount; i++)
     {
@@ -233,39 +228,39 @@ PHYSACDEF void UpdatePhysics()
             if (physicBodies[i]->rigidbody.enabled)
             {
                 // Apply friction to acceleration in X axis
-                    if (physicBodies[i]->rigidbody.acceleration.x > PHYSICS_ACCURACY) physicBodies[i]->rigidbody.acceleration.x -= physicBodies[i]->rigidbody.friction/PHYSICS_STEPS;
+                if (physicBodies[i]->rigidbody.acceleration.x > PHYSICS_ACCURACY) physicBodies[i]->rigidbody.acceleration.x -= physicBodies[i]->rigidbody.friction*deltaTime;
-                    else if (physicBodies[i]->rigidbody.acceleration.x < PHYSICS_ACCURACY) physicBodies[i]->rigidbody.acceleration.x += physicBodies[i]->rigidbody.friction/PHYSICS_STEPS;
+                else if (physicBodies[i]->rigidbody.acceleration.x < PHYSICS_ACCURACY) physicBodies[i]->rigidbody.acceleration.x += physicBodies[i]->rigidbody.friction*deltaTime;
                 else physicBodies[i]->rigidbody.acceleration.x = 0.0f;
                 
                 // Apply friction to acceleration in Y axis
-                    if (physicBodies[i]->rigidbody.acceleration.y > PHYSICS_ACCURACY) physicBodies[i]->rigidbody.acceleration.y -= physicBodies[i]->rigidbody.friction/PHYSICS_STEPS;
+                if (physicBodies[i]->rigidbody.acceleration.y > PHYSICS_ACCURACY) physicBodies[i]->rigidbody.acceleration.y -= physicBodies[i]->rigidbody.friction*deltaTime;
-                    else if (physicBodies[i]->rigidbody.acceleration.y < PHYSICS_ACCURACY) physicBodies[i]->rigidbody.acceleration.y += physicBodies[i]->rigidbody.friction/PHYSICS_STEPS;
+                else if (physicBodies[i]->rigidbody.acceleration.y < PHYSICS_ACCURACY) physicBodies[i]->rigidbody.acceleration.y += physicBodies[i]->rigidbody.friction*deltaTime;
                 else physicBodies[i]->rigidbody.acceleration.y = 0.0f;
                 
                 // Apply friction to velocity in X axis
-                    if (physicBodies[i]->rigidbody.velocity.x > PHYSICS_ACCURACY) physicBodies[i]->rigidbody.velocity.x -= physicBodies[i]->rigidbody.friction/PHYSICS_STEPS;
+                if (physicBodies[i]->rigidbody.velocity.x > PHYSICS_ACCURACY) physicBodies[i]->rigidbody.velocity.x -= physicBodies[i]->rigidbody.friction*deltaTime;
-                    else if (physicBodies[i]->rigidbody.velocity.x < PHYSICS_ACCURACY) physicBodies[i]->rigidbody.velocity.x += physicBodies[i]->rigidbody.friction/PHYSICS_STEPS;
+                else if (physicBodies[i]->rigidbody.velocity.x < PHYSICS_ACCURACY) physicBodies[i]->rigidbody.velocity.x += physicBodies[i]->rigidbody.friction*deltaTime;
                 else physicBodies[i]->rigidbody.velocity.x = 0.0f;
                 
                 // Apply friction to velocity in Y axis
-                    if (physicBodies[i]->rigidbody.velocity.y > PHYSICS_ACCURACY) physicBodies[i]->rigidbody.velocity.y -= physicBodies[i]->rigidbody.friction/PHYSICS_STEPS;
+                if (physicBodies[i]->rigidbody.velocity.y > PHYSICS_ACCURACY) physicBodies[i]->rigidbody.velocity.y -= physicBodies[i]->rigidbody.friction*deltaTime;
-                    else if (physicBodies[i]->rigidbody.velocity.y < PHYSICS_ACCURACY) physicBodies[i]->rigidbody.velocity.y += physicBodies[i]->rigidbody.friction/PHYSICS_STEPS;
+                else if (physicBodies[i]->rigidbody.velocity.y < PHYSICS_ACCURACY) physicBodies[i]->rigidbody.velocity.y += physicBodies[i]->rigidbody.friction*deltaTime;
                 else physicBodies[i]->rigidbody.velocity.y = 0.0f;
                 
                 // Apply gravity to velocity
                 if (physicBodies[i]->rigidbody.applyGravity)
                 {
-                        physicBodies[i]->rigidbody.velocity.x += gravityForce.x/PHYSICS_STEPS;
+                    physicBodies[i]->rigidbody.velocity.x += gravityForce.x*deltaTime;
-                        physicBodies[i]->rigidbody.velocity.y += gravityForce.y/PHYSICS_STEPS;
+                    physicBodies[i]->rigidbody.velocity.y += gravityForce.y*deltaTime;
                 }
                 
                 // Apply acceleration to velocity
-                    physicBodies[i]->rigidbody.velocity.x += physicBodies[i]->rigidbody.acceleration.x/PHYSICS_STEPS;
+                physicBodies[i]->rigidbody.velocity.x += physicBodies[i]->rigidbody.acceleration.x*deltaTime;
-                    physicBodies[i]->rigidbody.velocity.y += physicBodies[i]->rigidbody.acceleration.y/PHYSICS_STEPS;
+                physicBodies[i]->rigidbody.velocity.y += physicBodies[i]->rigidbody.acceleration.y*deltaTime;
                 
                 // Apply velocity to position
-                    physicBodies[i]->transform.position.x += physicBodies[i]->rigidbody.velocity.x/PHYSICS_STEPS;
+                physicBodies[i]->transform.position.x += physicBodies[i]->rigidbody.velocity.x*deltaTime;
-                    physicBodies[i]->transform.position.y -= physicBodies[i]->rigidbody.velocity.y/PHYSICS_STEPS;
+                physicBodies[i]->transform.position.y -= physicBodies[i]->rigidbody.velocity.y*deltaTime;
             }
             
             // Update collision detection
@@ -507,10 +502,7 @@ PHYSACDEF void UpdatePhysics()
                         }
                         
                         // Update rigidbody grounded state
-                            if (physicBodies[i]->rigidbody.enabled)
+                        if (physicBodies[i]->rigidbody.enabled) physicBodies[i]->rigidbody.isGrounded = (contactNormal.y < 0.0f);
-                            {
-                                if (contactNormal.y < 0.0f) physicBodies[i]->rigidbody.isGrounded = true;
-                            }
                         
                         // 2. Calculate collision impulse
                         // -------------------------------------------------------------------------------------------------------------------------------------
@@ -596,7 +588,6 @@ PHYSACDEF void UpdatePhysics()
         }
     }
 }
-}
 
 // Unitialize all physic objects and empty the objects pool
 PHYSACDEF void ClosePhysics()

src/raylib.h

@@ -582,6 +582,7 @@ Matrix GetCameraMatrix(Camera camera);                      // Returns camera tr
 void SetTargetFPS(int fps);                                 // Set target FPS (maximum)
 float GetFPS(void);                                         // Returns current FPS
 float GetFrameTime(void);                                   // Returns time in seconds for one frame
+double GetTime(void);                                       // Returns time since InitTimer() was run internally
 
 Color GetColor(int hexValue);                               // Returns a Color struct from hexadecimal value
 int GetHexValue(Color color);                               // Returns hexadecimal value for a Color