Added new Physac examples

examples/physics_demo.c

@@ -0,0 +1,122 @@
+/*******************************************************************************************
+*
+*   Physac - Physics demo
+*
+*   NOTE: Physac requires multi-threading, when InitPhysics() a second thread is created to manage physics calculations.
+*   The file pthreadGC2.dll is required to run the program; you can find it in 'src\external'
+*
+*   Copyright (c) 2016 Victor Fisac
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+#define PHYSAC_IMPLEMENTATION
+#include "..\src\physac.h"
+
+int main()
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    int screenWidth = 800;
+    int screenHeight = 450;
+
+    SetConfigFlags(FLAG_MSAA_4X_HINT);
+    InitWindow(screenWidth, screenHeight, "Physac [raylib] - Physics demo");
+    SetTargetFPS(60);
+
+    // Physac logo drawing position
+    int logoX = screenWidth - MeasureText("Physac", 30) - 10;
+    int logoY = 15;
+
+    // Initialize physics and default physics bodies
+    InitPhysics();
+
+    // Create floor rectangle physics body
+    PhysicsBody floor = CreatePhysicsBodyRectangle((Vector2){ screenWidth/2, screenHeight }, 500, 100, 10);
+    floor->enabled = false; // Disable body state to convert it to static (no dynamics, but collisions)
+
+    // Create obstacle circle physics body
+    PhysicsBody circle = CreatePhysicsBodyCircle((Vector2){ screenWidth/2, screenHeight/2 }, 45, 10);
+    circle->enabled = false; // Disable body state to convert it to static (no dynamics, but collisions)
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        if (IsKeyPressed('R'))    // Reset physics input
+        {
+            ResetPhysics();
+
+            floor = CreatePhysicsBodyRectangle((Vector2){ screenWidth/2, screenHeight }, 500, 100, 10);
+            floor->enabled = false;
+
+            circle = CreatePhysicsBodyCircle((Vector2){ screenWidth/2, screenHeight/2 }, 45, 10);
+            circle->enabled = false;
+        }
+
+        // Physics body creation inputs
+        if (IsMouseButtonPressed(MOUSE_LEFT_BUTTON)) CreatePhysicsBodyPolygon(GetMousePosition(), GetRandomValue(20, 80), GetRandomValue(3, 8), 10);
+        else if (IsMouseButtonPressed(MOUSE_RIGHT_BUTTON)) CreatePhysicsBodyCircle(GetMousePosition(), GetRandomValue(10, 45), 10);
+
+        // Destroy falling physics bodies
+        int bodiesCount = GetPhysicsBodiesCount();
+        for (int i = bodiesCount - 1; i >= 0; i--)
+        {
+            PhysicsBody body = GetPhysicsBody(i);
+            if (body != NULL && (body->position.y > screenHeight*2)) DestroyPhysicsBody(body);
+        }
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(BLACK);
+
+            DrawFPS(screenWidth - 90, screenHeight - 30);
+
+            // Draw created physics bodies
+            bodiesCount = GetPhysicsBodiesCount();
+            for (int i = 0; i < bodiesCount; i++)
+            {
+                PhysicsBody body = GetPhysicsBody(i);
+
+                if (body != NULL)
+                {
+                    int vertexCount = GetPhysicsShapeVerticesCount(i);
+                    for (int j = 0; j < vertexCount; j++)
+                    {
+                        // Get physics bodies shape vertices to draw lines
+                        // Note: GetPhysicsShapeVertex() already calculates rotation transformations
+                        Vector2 vertexA = GetPhysicsShapeVertex(body, j);
+
+                        int jj = (((j + 1) < vertexCount) ? (j + 1) : 0);   // Get next vertex or first to close the shape
+                        Vector2 vertexB = GetPhysicsShapeVertex(body, jj);
+
+                        DrawLineV(vertexA, vertexB, GREEN);     // Draw a line between two vertex positions
+                    }
+                }
+            }
+
+            DrawText("Left mouse button to create a polygon", 10, 10, 10, WHITE);
+            DrawText("Right mouse button to create a circle", 10, 25, 10, WHITE);
+            DrawText("Press 'R' to reset example", 10, 40, 10, WHITE);
+
+            DrawText("Physac", logoX, logoY, 30, WHITE);
+            DrawText("Powered by", logoX + 50, logoY - 7, 10, WHITE);
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------   
+    ClosePhysics();       // Unitialize physics
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}