Redesigned physics module (IN PROGRESS)

physac modules is being redesigned. Physics base behaviour is done and
it is composed by three steps: apply physics, resolve collisions and fix
overlapping.

A basic example is currently in progress. The next steps are try to add
torque and unoriented physic collisions and implement physics basic
functions to add forces. Rigidbody grounding state is automatically
calculated and has a perfect result. Rigidbodies interacts well with
each others.

To achieve physics accuracy, UpdatePhysics() is called a number of times
per frame. In a future, it should be changed to another thread and call
it without any target frame restriction.

Basic physics example has been redone (not finished) using the new
module functions. Forces examples will be redone so I removed it from
branch.

src/raylib.h

@@ -465,37 +465,40 @@ typedef struct {
 // Camera system modes
 typedef enum { CAMERA_CUSTOM = 0, CAMERA_FREE, CAMERA_ORBITAL, CAMERA_FIRST_PERSON, CAMERA_THIRD_PERSON } CameraMode;
 
-// Collider types
 typedef enum { COLLIDER_CIRCLE, COLLIDER_RECTANGLE, COLLIDER_CAPSULE } ColliderType;
 
-// Transform struct
 typedef struct Transform {
     Vector2 position;
     float rotation;
     Vector2 scale;
 } Transform;
 
-// Rigidbody struct
 typedef struct Rigidbody {
-    bool enabled;
+    bool enabled;           // Acts as kinematic state (collisions are calculated anyway)
     float mass;
     Vector2 acceleration;
     Vector2 velocity;
-    bool isGrounded;
-    bool isContact;     // Avoid freeze player when touching floor
     bool applyGravity;
-    float friction;     // 0.0f to 1.0f
-    float bounciness;   // 0.0f to 1.0f
+    bool isGrounded;
+    float friction;         // Normalized value
+    float bounciness;       // Normalized value
 } Rigidbody;
 
-// Collider struct
 typedef struct Collider {
     bool enabled;
     ColliderType type;
-    Rectangle bounds;   // Used for COLLIDER_RECTANGLE and COLLIDER_CAPSULE
-    int radius;         // Used for COLLIDER_CIRCLE and COLLIDER_CAPSULE
+    Rectangle bounds;       // Used for COLLIDER_RECTANGLE and COLLIDER_CAPSULE
+    int radius;             // Used for COLLIDER_CIRCLE and COLLIDER_CAPSULE
 } Collider;
 
+typedef struct PhysicObject {
+    unsigned int id;
+    Transform transform;
+    Rigidbody rigidbody;
+    Collider collider;
+    bool enabled;
+} PhysicObject;
+
 #ifdef __cplusplus
 extern "C" {            // Prevents name mangling of functions
 #endif
@@ -800,25 +803,17 @@ void SetShaderMap(Shader *shader, int mapLocation, Texture2D texture, int textur
 void SetBlendMode(int mode);                                        // Set blending mode (alpha, additive, multiplied)
 
 //----------------------------------------------------------------------------------
-// Physics System Functions (engine-module: physac)
+// Physics System Functions (Module: physac)
 //----------------------------------------------------------------------------------
-void InitPhysics(int maxPhysicElements);                                    // Initialize all internal physics values
-void UnloadPhysics();                                                       // Unload physic elements arrays
+void InitPhysics();                                                                     // Initializes pointers array (just pointers, fixed size)
+void UpdatePhysics();                                                                   // Update physic objects, calculating physic behaviours and collisions detection
+void ClosePhysics();                                                                    // Unitialize all physic objects and empty the objects pool
 
-void AddRigidbody(int index, Rigidbody rigidbody);                          // Initialize a new rigidbody with parameters to internal index slot
-void AddCollider(int index, Collider collider);                             // Initialize a new Collider with parameters to internal index slot
+PhysicObject *CreatePhysicObject(Vector2 position, float rotation, Vector2 scale);      // Create a new physic object dinamically, initialize it and add to pool
+void DestroyPhysicObject(PhysicObject *pObj);                                           // Destroy a specific physic object and take it out of the list
 
-void ApplyPhysics(int index, Vector2 *position);                            // Apply physics to internal rigidbody, physics calculations are applied to position pointer parameter
-void SetRigidbodyEnabled(int index, bool state);                            // Set enabled state to a defined rigidbody
-void SetRigidbodyVelocity(int index, Vector2 velocity);                     // Set velocity of rigidbody (without considering of mass value)
-void SetRigidbodyAcceleration(int index, Vector2 acceleration);             // Set acceleration of rigidbody (without considering of mass value)
-void AddRigidbodyForce(int index, Vector2 force);                           // Set rigidbody force (considering mass value)
-void AddForceAtPosition(Vector2 position, float intensity, float radius);   // Add a force to all enabled rigidbodies at a position
-
-void SetColliderEnabled(int index, bool state);                             // Set enabled state to a defined collider
-
-Rigidbody GetRigidbody(int index);                                          // Returns the internal rigidbody data defined by index parameter
-Collider GetCollider(int index);                                            // Returns the internal collider data defined by index parameter
+Rectangle TransformToRectangle(Transform transform);                                    // Convert Transform data type to Rectangle (position and scale)
+void DrawPhysicObjectInfo(PhysicObject *pObj, Vector2 position, int fontSize);          // Draw physic object information at screen position
 
 //------------------------------------------------------------------------------------
 // Audio Loading and Playing Functions (Module: audio)