/*******************************************************************************************
*
* raylib [physac] example - Forces
*
* This example has been created using raylib 1.5 (www.raylib.com)
* raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
*
* NOTE:
* Physac requires multi-threading, when InitPhysics() a second thread is created to manage
* physics calculations. To accomplish that, physac uses pthread Win32 library that can be
* found inside raylib/src/external/pthread directory.
*
* Add pthread library when compiling physac example:
* gcc -o $(NAME_PART).exe $(FILE_NAME) $(RAYLIB_DIR)\raylib_icon -L../src/external/pthread/lib \
* -I../src -I../src/external/pthread/include -lraylib -lglfw3 -lopengl32 -lgdi32 -lpthreadGC2 -std=c99 -Wall
*
* Note that pthreadGC2.dll must be also copied to project directory!
*
* Copyright (c) 2016 Victor Fisac and Ramon Santamaria (@raysan5)
*
********************************************************************************************/
#include "raylib.h"
#define PHYSAC_IMPLEMENTATION
#include "physac.h"
#define FORCE_AMOUNT 5.0f
#define FORCE_RADIUS 150
#define LINE_LENGTH 75
#define TRIANGLE_LENGTH 12
int main()
{
// Initialization
//--------------------------------------------------------------------------------------
int screenWidth = 800;
int screenHeight = 450;
InitWindow(screenWidth, screenHeight, "raylib [physac] example - forces");
InitPhysics((Vector2){ 0.0f, -9.81f/2 }); // Initialize physics module
// Global variables
Vector2 mousePosition;
bool isDebug = false;
// Create rectangle physic objects
PhysicBody rectangles[3];
for (int i = 0; i < 3; i++)
{
rectangles[i] = CreatePhysicBody((Vector2){ screenWidth/4*(i+1), (((i % 2) == 0) ? (screenHeight/3) : (screenHeight/1.5f)) }, 0.0f, (Vector2){ 50, 50 });
rectangles[i]->rigidbody.enabled = true; // Enable physic object rigidbody behaviour
rectangles[i]->rigidbody.friction = 0.1f;
}
// Create circles physic objects
// NOTE: when creating circle physic objects, transform.scale must be { 0, 0 } and object radius must be defined in collider.radius and use this value to draw the circle.
PhysicBody circles[3];
for (int i = 0; i < 3; i++)
{
circles[i] = CreatePhysicBody((Vector2){ screenWidth/4*(i+1), (((i % 2) == 0) ? (screenHeight/1.5f) : (screenHeight/4)) }, 0.0f, (Vector2){ 0, 0 });
circles[i]->rigidbody.enabled = true; // Enable physic object rigidbody behaviour
circles[i]->rigidbody.friction = 0.1f;
circles[i]->collider.type = COLLIDER_CIRCLE;
circles[i]->collider.radius = 25;
}
// Create walls physic objects
PhysicBody leftWall = CreatePhysicBody((Vector2){ -25, screenHeight/2 }, 0.0f, (Vector2){ 50, screenHeight });
PhysicBody rightWall = CreatePhysicBody((Vector2){ screenWidth + 25, screenHeight/2 }, 0.0f, (Vector2){ 50, screenHeight });
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 });
SetTargetFPS(60);
//--------------------------------------------------------------------------------------
// Main game loop
while (!WindowShouldClose()) // Detect window close button or ESC key
{
// Update
//----------------------------------------------------------------------------------
// Update mouse position value
mousePosition = GetMousePosition();
// Check force input
if (IsMouseButtonPressed(MOUSE_LEFT_BUTTON)) ApplyForceAtPosition(mousePosition, FORCE_AMOUNT, FORCE_RADIUS);
// Check reset input
if (IsKeyPressed('R'))
{
// Reset rectangle physic objects positions
for (int i = 0; i < 3; i++)
{
rectangles[i]->transform.position = (Vector2){ screenWidth/4*(i+1) - rectangles[i]->transform.scale.x/2, (((i % 2) == 0) ? (screenHeight/3) : (screenHeight/1.5f)) - rectangles[i]->transform.scale.y/2 };
rectangles[i]->rigidbody.velocity =(Vector2){ 0.0f, 0.0f };
}
// Reset circles physic objects positions
for (int i = 0; i < 3; i++)
{
circles[i]->transform.position = (Vector2){ screenWidth/4*(i+1), (((i % 2) == 0) ? (screenHeight/1.5f) : (screenHeight/4)) };
circles[i]->rigidbody.velocity =(Vector2){ 0.0f, 0.0f };
}
}
// Check debug switch input
if (IsKeyPressed('P')) isDebug = !isDebug;
//----------------------------------------------------------------------------------
// Draw
//----------------------------------------------------------------------------------
BeginDrawing();
ClearBackground(RAYWHITE);
// Draw rectangles
for (int i = 0; i < 3; i++)
{
// Convert transform values to rectangle data type variable
DrawRectangleRec(TransformToRectangle(rectangles[i]->transform), RED);
if (isDebug) DrawRectangleLines(rectangles[i]->collider.bounds.x, rectangles[i]->collider.bounds.y, rectangles[i]->collider.bounds.width, rectangles[i]->collider.bounds.height, GREEN);
// Draw force radius
DrawCircleLines(mousePosition.x, mousePosition.y, FORCE_RADIUS, BLACK);
// Draw direction lines
if (CheckCollisionPointCircle((Vector2){ rectangles[i]->transform.position.x + rectangles[i]->transform.scale.x/2, rectangles[i]->transform.position.y + rectangles[i]->transform.scale.y/2 }, mousePosition, FORCE_RADIUS))
{
Vector2 direction = { rectangles[i]->transform.position.x + rectangles[i]->transform.scale.x/2 - mousePosition.x, rectangles[i]->transform.position.y + rectangles[i]->transform.scale.y/2 - mousePosition.y };
float angle = atan2l(direction.y, direction.x);
// Calculate arrow start and end positions
Vector2 startPosition = { rectangles[i]->transform.position.x + rectangles[i]->transform.scale.x/2, rectangles[i]->transform.position.y + rectangles[i]->transform.scale.y/2 };
Vector2 endPosition = { rectangles[i]->transform.position.x + rectangles[i]->transform.scale.x/2 + (cos(angle)*LINE_LENGTH), rectangles[i]->transform.position.y + rectangles[i]->transform.scale.y/2 + (sin(angle)*LINE_LENGTH) };
// Draw arrow line
DrawLineV(startPosition, endPosition, BLACK);
// Draw arrow triangle
DrawTriangleLines((Vector2){ endPosition.x - cos(angle + 90*DEG2RAD)*LINE_LENGTH/TRIANGLE_LENGTH, endPosition.y - sin(angle + 90*DEG2RAD)*LINE_LENGTH/TRIANGLE_LENGTH },
(Vector2){ endPosition.x + cos(angle + 90*DEG2RAD)*LINE_LENGTH/TRIANGLE_LENGTH, endPosition.y + sin(angle + 90*DEG2RAD)*LINE_LENGTH/TRIANGLE_LENGTH },
(Vector2){ endPosition.x + cos(angle)*LINE_LENGTH/TRIANGLE_LENGTH*2, endPosition.y + sin(angle)*LINE_LENGTH/TRIANGLE_LENGTH*2 }, BLACK);
}
}
// Draw circles
for (int i = 0; i < 3; i++)
{
DrawCircleV(circles[i]->transform.position, circles[i]->collider.radius, BLUE);
if (isDebug) DrawCircleLines(circles[i]->transform.position.x, circles[i]->transform.position.y, circles[i]->collider.radius, GREEN);
// Draw force radius
DrawCircleLines(mousePosition.x, mousePosition.y, FORCE_RADIUS, BLACK);
// Draw direction lines
if (CheckCollisionPointCircle((Vector2){ circles[i]->transform.position.x, circles[i]->transform.position.y }, mousePosition, FORCE_RADIUS))
{
Vector2 direction = { circles[i]->transform.position.x - mousePosition.x, circles[i]->transform.position.y - mousePosition.y };
float angle = atan2l(direction.y, direction.x);
// Calculate arrow start and end positions
Vector2 startPosition = { circles[i]->transform.position.x, circles[i]->transform.position.y };
Vector2 endPosition = { circles[i]->transform.position.x + (cos(angle)*LINE_LENGTH), circles[i]->transform.position.y + (sin(angle)*LINE_LENGTH) };
// Draw arrow line
DrawLineV(startPosition, endPosition, BLACK);
// Draw arrow triangle
DrawTriangleLines((Vector2){ endPosition.x - cos(angle + 90*DEG2RAD)*LINE_LENGTH/TRIANGLE_LENGTH, endPosition.y - sin(angle + 90*DEG2RAD)*LINE_LENGTH/TRIANGLE_LENGTH },
(Vector2){ endPosition.x + cos(angle + 90*DEG2RAD)*LINE_LENGTH/TRIANGLE_LENGTH, endPosition.y + sin(angle + 90*DEG2RAD)*LINE_LENGTH/TRIANGLE_LENGTH },
(Vector2){ endPosition.x + cos(angle)*LINE_LENGTH/TRIANGLE_LENGTH*2, endPosition.y + sin(angle)*LINE_LENGTH/TRIANGLE_LENGTH*2 }, BLACK);
}
}
// Draw help messages
DrawText("Use LEFT MOUSE BUTTON to apply a force", screenWidth/2 - MeasureText("Use LEFT MOUSE BUTTON to apply a force", 20)/2, screenHeight*0.075f, 20, LIGHTGRAY);
DrawText("Use R to reset objects position", screenWidth/2 - MeasureText("Use R to reset objects position", 20)/2, screenHeight*0.875f, 20, GRAY);
DrawFPS(10, 10);
EndDrawing();
//----------------------------------------------------------------------------------
}
// De-Initialization
//--------------------------------------------------------------------------------------
ClosePhysics(); // Unitialize physics module
CloseWindow(); // Close window and OpenGL context
//--------------------------------------------------------------------------------------
return 0;
}