text: /*******************************************************************************************
  *
  *   raylib [core] example - smooth pixel-perfect camera
  *
  *   This example has been created using raylib 3.7 (www.raylib.com)
  *   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
  *
  *   Example contributed by Giancamillo Alessandroni ([discord]NotManyIdeas#9972 - [github]NotManyIdeasDev) and
  *   reviewed by Ramon Santamaria (@raysan5)
  *
  *   Copyright (c) 2021 Giancamillo Alessandroni (NotManyIdeas#9972) and Ramon Santamaria (@raysan5)
  *
  ********************************************************************************************/
  
  #include "raylib.h"
  #include <math.h>
  
  int main(void)
  {
      // Initialization
      //--------------------------------------------------------------------------------------
      const int screenWidth = 800;
      const int screenHeight = 450;
  
      const int virualScreenWidth = 160;
      const int virtualScreenHeight = 90;
  
      const float virtualRatio = (float)screenWidth/(float)virualScreenWidth;
  
      InitWindow(screenWidth, screenHeight, "raylib [core] example - smooth pixel-perfect camera");
  
      Camera2D worldSpaceCamera = { 0 }; // Game world camera
      worldSpaceCamera.zoom = 1.0f;
  
      Camera2D screenSpaceCamera = { 0 }; //Smoothing camera
      screenSpaceCamera.zoom = 1.0f;
  
      RenderTexture2D renderTexture = LoadRenderTexture(virualScreenWidth, virtualScreenHeight); //This is where we'll draw all our objects.
  
      Rectangle firstRectangle = { 70.0f, 35.0f, 20.0f, 20.0f };
      Rectangle secondRectangle = { 90.0f, 55.0f, 30.0f, 10.0f };
      Rectangle thirdRectangle = { 80.0f, 65.0f, 15.0f, 25.0f };
  
      //The renderTexture's height is flipped (in the source Rectangle), due to OpenGL reasons.
      Rectangle renderTextureSource = { 0.0f, 0.0f, (float)renderTexture.texture.width, (float)-renderTexture.texture.height };
      Rectangle renderTextureDest = { -virtualRatio, -virtualRatio, screenWidth + (virtualRatio*2), screenHeight + (virtualRatio*2) };
  
      Vector2 origin = { 0.0f, 0.0f };
  
      float rotation = 0.0f;
      float degreesPerSecond = 60.0f;
  
      float cameraX = 0.0f;
      float cameraY = 0.0f;
  
      SetTargetFPS(60);
      //--------------------------------------------------------------------------------------
  
      // Main game loop
      while (!WindowShouldClose())    // Detect window close button or ESC key
      {
          // Update
          //----------------------------------------------------------------------------------
          rotation += degreesPerSecond*GetFrameTime(); // Rotate the rectangles.
  
          // Make the camera move to demonstrate the effect.
          cameraX = (sinf(GetTime())*50.0f) - 10.0f;
          cameraY = cosf(GetTime())*30.0f;
  
          // Set the camera's target to the values computed above.
          screenSpaceCamera.target = (Vector2){ cameraX, cameraY };
  
          // Round worldCamera's X, keep the decimals on screenSpaceCamera.
          if (screenSpaceCamera.target.x >= 1 || screenSpaceCamera.target.x <= -1)
          {
              worldSpaceCamera.target.x = (int)screenSpaceCamera.target.x;
              screenSpaceCamera.target.x -= worldSpaceCamera.target.x;
              screenSpaceCamera.target.x *= virtualRatio;
          }
  
          // Round worldCamera's Y, keep the decimals on screenSpaceCamera.
          if (screenSpaceCamera.target.y >= 1 || screenSpaceCamera.target.y <= -1)
          {
              worldSpaceCamera.target.y = (int)screenSpaceCamera.target.y;
              screenSpaceCamera.target.y -= worldSpaceCamera.target.y;
              screenSpaceCamera.target.y *= virtualRatio;
          }
          //----------------------------------------------------------------------------------
  
          // Draw
          //----------------------------------------------------------------------------------
          BeginDrawing();
          ClearBackground(RED); // This is for debug purposes. If you see red, then you've probably done something wrong.
  
          BeginTextureMode(renderTexture);
          BeginMode2D(worldSpaceCamera);
          ClearBackground(RAYWHITE); // This is the color you should see as background color.
  
          // Draw the rectangles
          DrawRectanglePro(firstRectangle, origin, rotation, BLACK);
          DrawRectanglePro(secondRectangle, origin, -rotation, RED);
          DrawRectanglePro(thirdRectangle, origin, rotation + 45.0f, BLUE);
  
          EndMode2D();
          EndTextureMode();
  
          BeginMode2D(screenSpaceCamera);
  
          // Draw the render texture with an offset of 1 worldSpace unit/pixel, so that the content behind the renderTexture is not shown.
          DrawTexturePro(
              renderTexture.texture,
              renderTextureSource,
              renderTextureDest,
              origin,
              0.0f,
              WHITE
          );
  
          EndMode2D();
  
          //Debug info
          DrawText("Screen resolution: 800x450", 5, 0, 20, DARKBLUE);
          DrawText("World resolution: 160x90", 5, 20, 20, DARKGREEN);
          DrawFPS(screenWidth - 75, 0);
          EndDrawing();
          //----------------------------------------------------------------------------------
      }
  
      // De-Initialization
      //--------------------------------------------------------------------------------------
      UnloadRenderTexture(renderTexture); // RenderTexture unloading
      CloseWindow();        // Close window and OpenGL context
      //--------------------------------------------------------------------------------------
  
      return 0;
  }