Method draw

src/image.js:59–103

(tiles)

  }

  async draw(tiles) {
    this.tempBuffer = null;
    if (!this.image) {
      // Generate baseimage
      const baselayer = sharp({
        create: {
          width: this.width,
          height: this.height,
          channels: 4,
          background: {
            r: 0, g: 0, b: 0, alpha: 0,
          },
        },
      });
      // Save baseImage as buffer
      this.tempBuffer = await baselayer.png().toBuffer();
    } else {
      this.tempBuffer = this.image;
    }

    // Prepare tiles for composing baselayer
    const tileParts = [];
    tiles.forEach((tile, i) => {
      tileParts.push(this.prepareTileParts(tile, i));
    });

    const preparedTiles = (await Promise.all(tileParts)).filter((v) => v.success);

    // Compose all prepared tiles to the baselayer
    const preparedTilesForSharp = preparedTiles
      .filter((preparedTile) => !!preparedTile) // remove non-existing tiles
      .map((preparedTile) => {
        const { position, data } = preparedTile;
        position.top = Math.round(position.top);
        position.left = Math.round(position.left);
        return { input: data, ...position };
      });

    this.tempBuffer = await sharp(this.tempBuffer)
      .composite(preparedTilesForSharp)
      .toBuffer();

    this.image = this.tempBuffer;
    return true;
  }

  /**
   * Save image to file