CollisionDetection/CollisionDetection.ino

fabgl::Scene, sprites and collision detection example

/*
  Created by Fabrizio Di Vittorio (fdivitto2013@gmail.com) - www.fabgl.com
  Copyright (c) 2019 Fabrizio Di Vittorio.
  All rights reserved.

  This file is part of FabGL Library.

  FabGL is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  FabGL is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with FabGL.  If not, see <http://www.gnu.org/licenses/>.
 */


#include "fabgl.h"

#include "bitmaps.h"



#define SPACESHIP_COUNT 10
#define ASTEROID_COUNT   4

#define OBJECTS_COUNT (SPACESHIP_COUNT + ASTEROID_COUNT + 1)    // +1 = is for jupiter!


struct MySprite : Sprite {
  int  velX;
  int  velY;
  bool isAlive;
  bool isAsteroid;
};


struct MyScene : public Scene {

  MySprite objects_[OBJECTS_COUNT];

  MyScene()
    : Scene(OBJECTS_COUNT)
  {
  }

  void startSprite(MySprite * sprite)
  {
    // set initial position to one of the four sides of the screen
    int q = random(4);  // select beginning screen side
    int x = (q == 0 ? random(getWidth()) : (q == 1 ? getWidth() - sprite->getWidth() : (q == 2 ? random(getWidth())                : 0)));
    int y = (q == 0 ? 0                  : (q == 1 ? random(getHeight())             : (q == 2 ? getHeight() - sprite->getHeight() : random(getHeight()))));
    sprite->moveTo(x, y);
    sprite->visible = true;
    sprite->velX    = - sprite->getWidth() / 4  + random(sprite->getWidth() / 2);
    sprite->velY    = - sprite->getHeight() / 4 + random(sprite->getHeight() / 2);
    sprite->isAlive = true;
  }

  void init()
  {
    paintSpace();

    // setup spaceship and asteroid sprites
    for (int i = 0; i < OBJECTS_COUNT; ++i) {
      MySprite * sprite = &objects_[i];
      if (i == 0) {
        // setup Jupiter sprite
        sprite->addBitmap(&jupiter);
        sprite->moveTo(0, getHeight() / 2);
      } else if (i <= SPACESHIP_COUNT) {
        // each spaceship sprite of type Ship has 9 bitmaps: one "spaceship" bitmap and eight "explosion[]" bitmaps
        sprite->addBitmap(&spaceship)->addBitmap(explosion, 8);
        sprite->isAsteroid = false;
        addSprite(sprite); // add sprite to collision detector
        startSprite(sprite);
      } else {
        // each spaceship sprite of type Asteroid has just one bitmap: "asteroid"
        sprite->addBitmap(&asteroid);
        sprite->isAsteroid = true;
        addSprite(sprite); // add sprite to collision detector
        startSprite(sprite);
      }
    }

    VGAController.setSprites(objects_, OBJECTS_COUNT);
  }

  void update(int updateCount)
  {
    for (int i = 1; i < OBJECTS_COUNT; ++i) {

      MySprite * sprite = &objects_[i];

      // just alive objects can be moved or checked for collisions
      if (sprite->isAlive) {

        // this object is alive, move to the next position
        sprite->move(sprite->velX, sprite->velY);

        // update the collision detector and check for a possible collision
        updateSpriteAndDetectCollisions(sprite);

      } else if ((updateCount % 8) == 0) {

        // this sprite is dead, go to next frame (animate explosion) every 8 updates
        sprite->nextFrame();
        if (sprite->currentFrame == 0)
          startSprite(sprite);  // explosion animation ended, live again

      }
    }

    // move Jupiter every 20 updates
    if ((updateCount % 20) == 0)
      objects_[0].move(1, 0);

    VGAController.refreshSprites();
  }

  void collisionDetected(Sprite * spriteA, Sprite * spriteB, Point collisionPoint)
  {
    MySprite * a = (MySprite*) spriteA;
    MySprite * b = (MySprite*) spriteB;
    // two asteroids cannot colide
    if (a->isAsteroid && b->isAsteroid)
      return;
    // collision ok, mark both objects as dead
    a->isAlive = b->isAlive = false;
    // if collided object is an asteroid no explosion is shown, just hide it. Otherwise go to next frame.
    if (a->isAsteroid)
      a->visible = false;
    else
      a->nextFrame();
    if (b->isAsteroid)
      b->visible = false;
    else
      b->nextFrame();
  }

  void paintSpace()
  {
    Canvas.setBrushColor(Color::Black);
    Canvas.clear();
    Canvas.setPenColor(Color::White);
    Canvas.setBrushColor(Color::White);
    // far stars
    Canvas.setPenColor(1, 1, 1);
    for (int i = 0; i < 400; ++i)
      Canvas.setPixel(random(getWidth()), random(getHeight()));
    // near stars
    Canvas.setPenColor(2, 2, 2);
    for (int i = 0; i < 50; ++i)
      Canvas.setPixel(random(getWidth()), random(getHeight()));
    // galaxy
    Canvas.drawBitmap(80, 35, &galaxy);
    Canvas.drawBitmap(220, 130, &galaxy);
  }

};


void setup()
{
  // just for debug
  Serial.begin(115200);

  VGAController.begin();
  VGAController.setResolution(VGA_320x200_75Hz);
  //VGAController.moveScreen(20, 0);
  VGAController.moveScreen(-8, 0);
}


void loop()
{
  MyScene scene;
  scene.start();
  vTaskSuspend(nullptr);
}