sigma/rendering/webgl/shaders/utils.js

A JavaScript library dedicated to graph drawing.

"use strict";
/**
 * Sigma.js Shader Utils
 * ======================
 *
 * Code used to load sigma's shaders.
 * @module
 */
Object.defineProperty(exports, "__esModule", { value: true });
exports.loadProgram = exports.loadFragmentShader = exports.loadVertexShader = void 0;
/**
 * Function used to load a shader.
 */
function loadShader(type, gl, source) {
    var glType = type === "VERTEX" ? gl.VERTEX_SHADER : gl.FRAGMENT_SHADER;
    // Creating the shader
    var shader = gl.createShader(glType);
    if (shader === null) {
        throw new Error("loadShader: error while creating the shader");
    }
    // Loading source
    gl.shaderSource(shader, source);
    // Compiling the shader
    gl.compileShader(shader);
    // Retrieving compilation status
    var successfullyCompiled = gl.getShaderParameter(shader, gl.COMPILE_STATUS);
    // Throwing if something went awry
    if (!successfullyCompiled) {
        var infoLog = gl.getShaderInfoLog(shader);
        gl.deleteShader(shader);
        throw new Error("loadShader: error while compiling the shader:\n" + infoLog + "\n" + source);
    }
    return shader;
}
function loadVertexShader(gl, source) {
    return loadShader("VERTEX", gl, source);
}
exports.loadVertexShader = loadVertexShader;
function loadFragmentShader(gl, source) {
    return loadShader("FRAGMENT", gl, source);
}
exports.loadFragmentShader = loadFragmentShader;
/**
 * Function used to load a program.
 */
function loadProgram(gl, shaders) {
    var program = gl.createProgram();
    if (program === null) {
        throw new Error("loadProgram: error while creating the program.");
    }
    var i, l;
    // Attaching the shaders
    for (i = 0, l = shaders.length; i < l; i++)
        gl.attachShader(program, shaders[i]);
    gl.linkProgram(program);
    // Checking status
    var successfullyLinked = gl.getProgramParameter(program, gl.LINK_STATUS);
    if (!successfullyLinked) {
        gl.deleteProgram(program);
        throw new Error("loadProgram: error while linking the program.");
    }
    return program;
}
exports.loadProgram = loadProgram;