Method _xtermGraphicsAttributes

addons/addon-image/src/ImageAddon.ts:249–316

* Implementation of xterm's graphics attribute sequence. * * Supported features: * - read/change palette limits (max 4096 by sixel lib) * - read SIXEL canvas geometry (reports current window canvas or * squared pixelLimit if canvas > pixel limit) * * Everything else is deactiv

(params: (number | number[])[])

   * Everything else is deactivated.
   */
  private _xtermGraphicsAttributes(params: (number | number[])[]): boolean {
    if (params.length < 2) {
      return true;
    }
    if (params[0] === GaItem.COLORS) {
      switch (params[1]) {
        case GaAction.READ:
          this._report(`\x1b[?${params[0]};${GaStatus.SUCCESS};${this._opts.sixelPaletteLimit}S`);
          return true;
        case GaAction.SET_DEFAULT:
          this._opts.sixelPaletteLimit = this._defaultOpts.sixelPaletteLimit;
          this._report(`\x1b[?${params[0]};${GaStatus.SUCCESS};${this._opts.sixelPaletteLimit}S`);
          // also reset protocol handlers for now
          for (const handler of this._handlers.values()) {
            handler.reset();
          }
          return true;
        case GaAction.SET:
          if (params.length > 2 && !(params[2] instanceof Array) && params[2] <= MAX_SIXEL_PALETTE_SIZE) {
            this._opts.sixelPaletteLimit = params[2];
            this._report(`\x1b[?${params[0]};${GaStatus.SUCCESS};${this._opts.sixelPaletteLimit}S`);
          } else {
            this._report(`\x1b[?${params[0]};${GaStatus.ACTION_ERROR}S`);
          }
          return true;
        case GaAction.READ_MAX:
          this._report(`\x1b[?${params[0]};${GaStatus.SUCCESS};${MAX_SIXEL_PALETTE_SIZE}S`);
          return true;
        default:
          this._report(`\x1b[?${params[0]};${GaStatus.ACTION_ERROR}S`);
          return true;
      }
    }
    if (params[0] === GaItem.SIXEL_GEO) {
      switch (params[1]) {
        // we only implement read and read_max here
        case GaAction.READ:
          let width = this._renderer?.dimensions?.css.canvas.width;
          let height = this._renderer?.dimensions?.css.canvas.height;
          if (!width || !height) {
            // for some reason we have no working image renderer
            // --> fallback to default cell size
            const cellSize = CELL_SIZE_DEFAULT;
            width = (this._terminal?.cols || 80) * cellSize.width;
            height = (this._terminal?.rows || 24) * cellSize.height;
          }
          if (width * height < this._opts.pixelLimit) {
            this._report(`\x1b[?${params[0]};${GaStatus.SUCCESS};${width.toFixed(0)};${height.toFixed(0)}S`);
          } else {
            // if we overflow pixelLimit report that squared instead
            const x = Math.floor(Math.sqrt(this._opts.pixelLimit));
            this._report(`\x1b[?${params[0]};${GaStatus.SUCCESS};${x};${x}S`);
          }
          return true;
        case GaAction.READ_MAX:
          // read_max returns pixelLimit as square area
          const x = Math.floor(Math.sqrt(this._opts.pixelLimit));
          this._report(`\x1b[?${params[0]};${GaStatus.SUCCESS};${x};${x}S`);