cione-comp-lib/es/node_modules/claygl/src/util/hdr.mjs

`$ yarn add cione-comp-lib` 或者 `$ npm i cione-comp-lib -S`

import Texture from "../Texture.mjs";
import Texture2D from "../Texture2D.mjs";
var toChar = String.fromCharCode;
var MINELEN = 8;
var MAXELEN = 32767;
function rgbe2float(rgbe, buffer, offset, exposure) {
  if (rgbe[3] > 0) {
    var f = Math.pow(2, rgbe[3] - 128 - 8 + exposure);
    buffer[offset + 0] = rgbe[0] * f;
    buffer[offset + 1] = rgbe[1] * f;
    buffer[offset + 2] = rgbe[2] * f;
  } else {
    buffer[offset + 0] = 0;
    buffer[offset + 1] = 0;
    buffer[offset + 2] = 0;
  }
  buffer[offset + 3] = 1;
  return buffer;
}
function uint82string(array, offset, size) {
  var str = "";
  for (var i = offset; i < size; i++) {
    str += toChar(array[i]);
  }
  return str;
}
function copyrgbe(s, t) {
  t[0] = s[0];
  t[1] = s[1];
  t[2] = s[2];
  t[3] = s[3];
}
function oldReadColors(scan, buffer, offset, xmax) {
  var rshift = 0, x = 0, len = xmax;
  while (len > 0) {
    scan[x][0] = buffer[offset++];
    scan[x][1] = buffer[offset++];
    scan[x][2] = buffer[offset++];
    scan[x][3] = buffer[offset++];
    if (scan[x][0] === 1 && scan[x][1] === 1 && scan[x][2] === 1) {
      for (var i = scan[x][3] << rshift >>> 0; i > 0; i--) {
        copyrgbe(scan[x - 1], scan[x]);
        x++;
        len--;
      }
      rshift += 8;
    } else {
      x++;
      len--;
      rshift = 0;
    }
  }
  return offset;
}
function readColors(scan, buffer, offset, xmax) {
  if (xmax < MINELEN | xmax > MAXELEN) {
    return oldReadColors(scan, buffer, offset, xmax);
  }
  var i = buffer[offset++];
  if (i != 2) {
    return oldReadColors(scan, buffer, offset - 1, xmax);
  }
  scan[0][1] = buffer[offset++];
  scan[0][2] = buffer[offset++];
  i = buffer[offset++];
  if ((scan[0][2] << 8 >>> 0 | i) >>> 0 !== xmax) {
    return null;
  }
  for (var i = 0; i < 4; i++) {
    for (var x = 0; x < xmax; ) {
      var code = buffer[offset++];
      if (code > 128) {
        code = (code & 127) >>> 0;
        var val = buffer[offset++];
        while (code--) {
          scan[x++][i] = val;
        }
      } else {
        while (code--) {
          scan[x++][i] = buffer[offset++];
        }
      }
    }
  }
  return offset;
}
var ret = {
  parseRGBE: function(arrayBuffer, texture, exposure) {
    if (exposure == null) {
      exposure = 0;
    }
    var data = new Uint8Array(arrayBuffer);
    var size = data.length;
    if (uint82string(data, 0, 2) !== "#?") {
      return;
    }
    for (var i = 2; i < size; i++) {
      if (toChar(data[i]) === "\n" && toChar(data[i + 1]) === "\n") {
        break;
      }
    }
    if (i >= size) {
      return;
    }
    i += 2;
    var str = "";
    for (; i < size; i++) {
      var _char = toChar(data[i]);
      if (_char === "\n") {
        break;
      }
      str += _char;
    }
    var tmp = str.split(" ");
    var height = parseInt(tmp[1]);
    var width = parseInt(tmp[3]);
    if (!width || !height) {
      return;
    }
    var offset = i + 1;
    var scanline = [];
    for (var x = 0; x < width; x++) {
      scanline[x] = [];
      for (var j = 0; j < 4; j++) {
        scanline[x][j] = 0;
      }
    }
    var pixels = new Float32Array(width * height * 4);
    var offset2 = 0;
    for (var y = 0; y < height; y++) {
      var offset = readColors(scanline, data, offset, width);
      if (!offset) {
        return null;
      }
      for (var x = 0; x < width; x++) {
        rgbe2float(scanline[x], pixels, offset2, exposure);
        offset2 += 4;
      }
    }
    if (!texture) {
      texture = new Texture2D();
    }
    texture.width = width;
    texture.height = height;
    texture.pixels = pixels;
    texture.type = Texture.FLOAT;
    return texture;
  },
  parseRGBEFromPNG: function(png) {
  }
};
var hdr = ret;
export { hdr as default };