mdx-m3-viewer/src/viewer/handlers/mdx/filtermode.js

A browser WebGL model viewer. Mainly focused on models of the games Warcraft 3 and Starcraft 2.

/**
 * @param {number} filterMode
 * @param {WebGLContext} gl
 * @return {Array<number>}
 */
export function layerFilterMode(filterMode, gl) {
  if (filterMode === 2) {
    return [gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA]; // Blend
  } else if (filterMode === 3) {
    return [gl.SRC_ALPHA, gl.ONE]; // Additive
  } else if (filterMode === 4) {
    return [gl.SRC_ALPHA, gl.ONE]; // Add alpha
  } else if (filterMode === 5) {
    return [gl.ZERO, gl.SRC_COLOR]; // Modulate
  } else if (filterMode === 6) {
    return [gl.DST_COLOR, gl.SRC_COLOR]; // Modulate 2x
  }

  return [0, 0];
}

/**
 * @param {number} filterMode
 * @param {WebGLContext} gl
 * @return {Array<number>}
 */
export function emitterFilterMode(filterMode, gl) {
  if (filterMode === 0) {
    return [gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA]; // Blend
  } else if (filterMode === 1) {
    return [gl.SRC_ALPHA, gl.ONE]; // Add alpha
  } else if (filterMode === 2) {
    return [gl.ZERO, gl.SRC_COLOR]; // Modulate
  } else if (filterMode === 3) {
    return [gl.DEST_COLOR, gl.SRC_COLOR]; // Modulate 2x
  } else if (filterMode === 4) {
    return [gl.SRC_ALPHA, gl.ONE]; // Add alpha
  }
}