camera_class.js

class CameraClass {
  constructor(canvas) {
    this.cameraX = 0;
    this.cameraY = 0;
    this.screenWidth = canvas.width;
    this.screenHeight = canvas.height;
    this.limitX = undefined;
    this.limitY = undefined;
    this.cameraZoom = 1.0;
    this.rotate = 0.0;
    this.validation();
  }

  setLimit(x, y) {
    this.limitX = x;
    this.limitY = y;
  }

  validation() {
    this.viewboxWidth = this.screenWidth / this.cameraZoom;
    this.viewboxHeight = this.screenHeight / this.cameraZoom;

    if (this.cameraX < this.viewboxWidth / 2) {
      const x = this.viewboxWidth / 2;
      this.viewboxLeft = x - this.viewboxWidth / 2;
      this.viewboxRight = x + this.viewboxWidth / 2;
      this.viewboxCenterX = x;
    } else if (
      this.limitX &&
      this.cameraX > this.limitX - this.viewboxWidth / 2
    ) {
      const x = this.limitX - this.viewboxWidth / 2;
      this.viewboxLeft = x - this.viewboxWidth / 2;
      this.viewboxRight = x + this.viewboxWidth / 2;
      this.viewboxCenterX = x;
    } else {
      this.viewboxLeft = this.cameraX - this.viewboxWidth / 2;
      this.viewboxRight = this.cameraX + this.viewboxWidth / 2;
      this.viewboxCenterX = this.cameraX;
    }

    if (this.cameraY < this.viewboxHeight / 2) {
      const y = this.viewboxHeight / 2;
      this.viewboxTop = y - this.viewboxHeight / 2;
      this.viewboxBottom = y + this.viewboxHeight / 2;
      this.viewboxCenterY = y;
    } else if (
      this.limitY &&
      this.cameraY > this.limitY - this.viewboxHeight / 2
    ) {
      const y = this.limitY - this.viewboxHeight / 2;
      this.viewboxTop = y - this.viewboxHeight / 2;
      this.viewboxBottom = y + this.viewboxHeight / 2;
      this.viewboxCenterY = y;
    } else {
      this.viewboxTop = this.cameraY - this.viewboxHeight / 2;
      this.viewboxBottom = this.cameraY + this.viewboxHeight / 2;
      this.viewboxCenterY = this.cameraY;
    }

    this.circumscriptionRadius =
      Math.sqrt(
        this.viewboxWidth * this.viewboxWidth +
          this.viewboxHeight * this.viewboxHeight
      ) / 2;
    this.circumscriptionRect = {
      left: this.viewboxCenterX - this.circumscriptionRadius,
      top: this.viewboxCenterY - this.circumscriptionRadius,
      right: this.viewboxCenterX + this.circumscriptionRadius,
      bottom: this.viewboxCenterY + this.circumscriptionRadius,
    };
  }

  getRotate() {
    return this.rotate;
  }

  setRotate(rotate) {
    if (this.rotate !== rotate) {
      this.rotate = rotate;
    }
  }

  getCameraX() {
    return this.cameraX;
  }

  getCameraY() {
    return this.cameraY;
  }

  getViewboxWidth() {
    return this.viewboxWidth;
  }

  getViewboxHeight() {
    return this.viewboxHeight;
  }

  getViewboxLeft() {
    return this.viewboxLeft;
  }

  getViewboxTop() {
    return this.viewboxTop;
  }

  getViewboxRight() {
    return this.viewboxRight;
  }

  getViewboxBottom() {
    return this.viewboxBottom;
  }

  getViewboxCenterX() {
    return this.viewboxCenterX;
  }

  getViewboxCenterY() {
    return this.viewboxCenterY;
  }

  setCameraPosition(x, y) {
    this.cameraX = x;
    this.cameraY = y;
    this.validation();
  }

  moveCameraPosition(offsetX, offsetY) {
    this.cameraX += offsetX;
    this.cameraY += offsetY;
    this.validation();
  }

  setCameraZoom(zoom) {
    this.cameraZoom = zoom;
    this.validation();
  }

  containsPlayer(playerClass) {
    if (playerClass) {
      return true;
    }
    return false;
  }

  containsNpc(npcClass) {
    if (npcClass) {
      return true;
    }
    return false;
  }

  containsBox(x, y, width, height) {
    if (this.rotate === 0) {
      return (
        this.viewboxLeft < x + width &&
        this.viewboxRight > x &&
        this.viewboxTop < y + height &&
        this.viewboxBottom > y
      );
    } else {
      return (
        this.circumscriptionRect.left < x + width &&
        this.circumscriptionRect.right > x &&
        this.circumscriptionRect.top < y + height &&
        this.circumscriptionRect.bottom > y
      );
    }
  }
}