Function runResizeProgram

tfjs-react-native/src/camera/camera_webgl_util.ts:178–298

(
    gl: WebGL2RenderingContext, inputTexture: WebGLTexture,
    inputDims: Dimensions, outputDims: Dimensions, alignCorners: boolean,
    useCustomShadersToResize: boolean,
    interpolation: 'nearest_neighbor'|'bilinear', rotation: Rotation)

}

export function runResizeProgram(
    gl: WebGL2RenderingContext, inputTexture: WebGLTexture,
    inputDims: Dimensions, outputDims: Dimensions, alignCorners: boolean,
    useCustomShadersToResize: boolean,
    interpolation: 'nearest_neighbor'|'bilinear', rotation: Rotation) {
  const {program, vao, vertices, uniformLocations} = useCustomShadersToResize ?
      resizeProgram(gl, inputDims, outputDims, alignCorners, interpolation) :
      drawTextureProgram(gl, false, true, rotation);
  gl.useProgram(program);
  // Set up geometry
  webgl_util.callAndCheck(gl, () => {
    gl.bindVertexArray(vao);
  });

  //
  // Set up input texture
  //
  gl.uniform1i(uniformLocations.get('inputTexture'), 1);
  gl.activeTexture(gl.TEXTURE0 + 1);
  gl.bindTexture(gl.TEXTURE_2D, inputTexture);
  if (!useCustomShadersToResize) {
    const textureFilter =
        interpolation === 'nearest_neighbor' ? gl.NEAREST : gl.LINEAR;
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, textureFilter);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, textureFilter);
  }

  //
  // Set up output texture.
  //
  if (!resizeTextureCache.has(gl)) {
    resizeTextureCache.set(gl, gl.createTexture());
  }
  const resizeTexture = resizeTextureCache.get(gl);

  const targetTexture = resizeTexture;
  const targetTextureWidth = outputDims.width;
  const targetTextureHeight = outputDims.height;

  gl.activeTexture(gl.TEXTURE0 + 2);
  gl.bindTexture(gl.TEXTURE_2D, targetTexture);

  gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
  gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
  gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
  gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);

  // Reallocate texture storage if target size has changed.
  if (!resizeTextureDimsCache.has(gl)) {
    resizeTextureDimsCache.set(gl, {width: -1, height: -1});
  }
  const resizeTextureDims = resizeTextureDimsCache.get(gl);

  if (resizeTextureDims == null ||
      resizeTextureDims.width !== targetTextureWidth ||
      resizeTextureDims.height !== targetTextureHeight) {
    const level = 0;
    const format = outputDims.depth === 3 ? gl.RGB : gl.RGBA;