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import type {  Image as HTMLImage,  WebGLBuffer,  WebGLProgram,  WebGLRenderingContext,  WebGLShader,} from "../../../deps.ts";import { FrameBuffer } from "../../../mod.ts";
export function initShaderProgram(  gl: WebGLRenderingContext,  vertex: string,  fragment: string,): WebGLProgram {  const vertexShader = loadShader(gl, gl.VERTEX_SHADER, vertex);  const fragmentShader = loadShader(gl, gl.FRAGMENT_SHADER, fragment);
  const shaderProgram = gl.createProgram();  if (vertexShader && fragmentShader && shaderProgram) {    gl.attachShader(shaderProgram, vertexShader);    gl.attachShader(shaderProgram, fragmentShader);    gl.linkProgram(shaderProgram);
    if (!gl.getProgramParameter(shaderProgram, gl.LINK_STATUS)) {      const msg = gl.getProgramInfoLog(shaderProgram);      throw new Error(`Unable to initialize the shader program: ${msg}`);    }
    return shaderProgram;  }  throw new Error(`Unable to initialize the shader program!`);}
function loadShader(  gl: WebGLRenderingContext,  type: number,  source: string,): WebGLShader | null {  const shader = gl.createShader(type);  if (shader) {    gl.shaderSource(shader, source);    gl.compileShader(shader);
    if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) {      const msg = gl.getShaderInfoLog(shader);      gl.deleteShader(shader);      throw new Error(`An error occurred compiling the shaders: ${msg}`);    }
    return shader;  }  throw new Error(`An error occurred compiling the shaders!`);}
export function createBuffer(  gl: WebGLRenderingContext,  data: number[],  target: number = gl.ARRAY_BUFFER,  usage: number = gl.STATIC_DRAW,): WebGLBuffer {  const buffer = gl.createBuffer();  if (!buffer) throw new Error(`Could not create buffer!`);  gl.bindBuffer(target, buffer);  gl.bufferData(target, new Float32Array(data), usage);  return buffer;}
export function setBuffer(  gl: WebGLRenderingContext,  buffer: WebGLBuffer,  location: number,  numComponents: number,  type: number = gl.FLOAT,  target: number = gl.ARRAY_BUFFER,  normalize = false,  stride = 0,  offset = 0,): void {  if (!buffer) throw new Error(`Could not set buffer!`);  gl.bindBuffer(target, buffer);  gl.vertexAttribPointer(    location,    numComponents,    type,    normalize,    stride,    offset,  );  gl.enableVertexAttribArray(location);}
export function loadTexture(  gl: WebGLRenderingContext,  image: HTMLImage | FrameBuffer,  level = 0,  internalFormat = gl.RGBA,  border = 0,  srcFormat = gl.RGBA,  srcType = gl.UNSIGNED_BYTE,) {  const texture = gl.createTexture();  gl.bindTexture(gl.TEXTURE_2D, texture);  gl.texImage2D(    gl.TEXTURE_2D,    level,    internalFormat,    image.width,    image.height,    border,    srcFormat,    srcType,    image.rawData,  );
  if (isPowerOf2(image.width) && isPowerOf2(image.height)) {    gl.generateMipmap(gl.TEXTURE_2D);  } else {    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);    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);  }
  return texture;}
function isPowerOf2(value: number) {  return (value & (value - 1)) == 0;}