Class GhosttyTerminal

lib/ghostty.ts:254–789

 * - No per-row WASM boundary crossings!
 */
export class GhosttyTerminal {
  private exports: GhosttyWasmExports;
  private memory: WebAssembly.Memory;
  private handle: TerminalHandle;
  private _cols: number;
  private _rows: number;

  /** Size of GhosttyCell in WASM (16 bytes) */
  private static readonly CELL_SIZE = 16;

  /** Reusable buffer for viewport operations */
  private viewportBufferPtr: number = 0;
  private viewportBufferSize: number = 0;

  /** Cell pool for zero-allocation rendering */
  private cellPool: GhosttyCell[] = [];

  constructor(
    exports: GhosttyWasmExports,
    memory: WebAssembly.Memory,
    cols: number = 80,
    rows: number = 24,
    config?: GhosttyTerminalConfig
  ) {
    this.exports = exports;
    this.memory = memory;
    this._cols = cols;
    this._rows = rows;

    if (config) {
      // Allocate config struct in WASM memory
      const configPtr = this.exports.ghostty_wasm_alloc_u8_array(GHOSTTY_CONFIG_SIZE);
      if (configPtr === 0) {
        throw new Error('Failed to allocate config (out of memory)');
      }

      try {
        // Write config to WASM memory
        const view = new DataView(this.memory.buffer);
        let offset = configPtr;

        // scrollback_limit (u32)
        view.setUint32(offset, config.scrollbackLimit ?? 10000, true);
        offset += 4;

        // fg_color (u32)
        view.setUint32(offset, config.fgColor ?? 0, true);
        offset += 4;

        // bg_color (u32)
        view.setUint32(offset, config.bgColor ?? 0, true);
        offset += 4;

        // cursor_color (u32)
        view.setUint32(offset, config.cursorColor ?? 0, true);
        offset += 4;

        // palette[16] (u32 * 16)