git subrepo clone (merge) https://github.com/HarbourMasters/otrgui.git OTRGui

subrepo:
  subdir:   "OTRGui"
  merged:   "a6066a251"
upstream:
  origin:   "https://github.com/HarbourMasters/otrgui.git"
  branch:   "master"
  commit:   "a6066a251"
git-subrepo:
  version:  "0.4.1"
  origin:   "???"
  commit:   "???"

OTRGui/libs/raylib/examples/physics/physics_restitution.c

@@ -0,0 +1,129 @@
+/*******************************************************************************************
+*
+*   raylib [physac] example - physics restitution
+*
+*   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)
+*
+*   This example uses physac 1.1 (https://github.com/raysan5/raylib/blob/master/src/physac.h)
+*
+*   Copyright (c) 2016-2021 Victor Fisac (@victorfisac) and Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+#define PHYSAC_IMPLEMENTATION
+#include "extras/physac.h"
+
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 450;
+
+    SetConfigFlags(FLAG_MSAA_4X_HINT);
+    InitWindow(screenWidth, screenHeight, "raylib [physac] example - physics restitution");
+
+    // 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/2.0f, (float)screenHeight }, (float)screenWidth, 100, 10);
+    floor->enabled = false; // Disable body state to convert it to static (no dynamics, but collisions)
+    floor->restitution = 1;
+
+    // Create circles physics body
+    PhysicsBody circleA = CreatePhysicsBodyCircle((Vector2){ screenWidth*0.25f, screenHeight/2.0f }, 30, 10);
+    circleA->restitution = 0;
+    PhysicsBody circleB = CreatePhysicsBodyCircle((Vector2){ screenWidth*0.5f, screenHeight/2.0f }, 30, 10);
+    circleB->restitution = 0.5f;
+    PhysicsBody circleC = CreatePhysicsBodyCircle((Vector2){ screenWidth*0.75f, screenHeight/2.0f }, 30, 10);
+    circleC->restitution = 1;
+
+    // Restitution demo needs a very tiny physics time step for a proper simulation
+    SetPhysicsTimeStep(1.0/60.0/100*1000);
+
+    SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        UpdatePhysics();            // Update physics system
+
+        if (IsKeyPressed(KEY_R))    // Reset physics input
+        {
+            // Reset circles physics bodies position and velocity
+            circleA->position = (Vector2){ screenWidth*0.25f, screenHeight/2.0f };
+            circleA->velocity = (Vector2){ 0, 0 };
+            circleB->position = (Vector2){ screenWidth*0.5f, screenHeight/2.0f };
+            circleB->velocity = (Vector2){ 0, 0 };
+            circleC->position = (Vector2){ screenWidth*0.75f, screenHeight/2.0f };
+            circleC->velocity = (Vector2){ 0, 0 };
+        }
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(BLACK);
+
+            DrawFPS(screenWidth - 90, screenHeight - 30);
+
+            // Draw created physics bodies
+            int bodiesCount = GetPhysicsBodiesCount();
+            for (int i = 0; i < bodiesCount; i++)
+            {
+                PhysicsBody body = GetPhysicsBody(i);
+
+                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("Restitution amount", (screenWidth - MeasureText("Restitution amount", 30))/2, 75, 30, WHITE);
+            DrawText("0", (int)circleA->position.x - MeasureText("0", 20)/2, circleA->position.y - 7, 20, WHITE);
+            DrawText("0.5", (int)circleB->position.x - MeasureText("0.5", 20)/2, circleB->position.y - 7, 20, WHITE);
+            DrawText("1", (int)circleC->position.x - MeasureText("1", 20)/2, circleC->position.y - 7, 20, WHITE);
+
+            DrawText("Press 'R' to reset example", 10, 10, 10, WHITE);
+
+            DrawText("Physac", logoX, logoY, 30, WHITE);
+            DrawText("Powered by", logoX + 50, logoY - 7, 10, WHITE);
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    DestroyPhysicsBody(circleA);
+    DestroyPhysicsBody(circleB);
+    DestroyPhysicsBody(circleC);
+    DestroyPhysicsBody(floor);
+
+    ClosePhysics();       // Unitialize physics
+
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}