Add unit test and document optional scope parameter in build*Shader methods

Author: aashu2006

src/webgl/material.js

@@ -732,11 +732,13 @@ function material(p5, fn) {
    * @beta
    * @submodule p5.strands
    * @param {Function} callback A function building a p5.strands shader.
+   * @param {Object} [scope] An optional scope object passed to .modify().
    * @returns {p5.Shader} The material shader
    */
   /**
    * @method buildFilterShader
    * @param {Object} hooks An object specifying p5.strands hooks in GLSL.
+   * @param {Object} [scope] An optional scope object passed to .modify().
    * @returns {p5.Shader} The material shader
    */
   fn.buildFilterShader = function (callback, scope) {
@@ -1560,11 +1562,13 @@ function material(p5, fn) {
    * @submodule p5.strands
    * @beta
    * @param {Function} callback A function building a p5.strands shader.
+   * @param {Object} [scope] An optional scope object passed to .modify().
    * @returns {p5.Shader} The material shader.
    */
   /**
    * @method buildMaterialShader
    * @param {Object} hooks An object specifying p5.strands hooks in GLSL.
+   * @param {Object} [scope] An optional scope object passed to .modify().
    * @returns {p5.Shader} The material shader.
    */
   fn.buildMaterialShader = function (cb, scope) {
@@ -1776,11 +1780,13 @@ function material(p5, fn) {
    * @submodule p5.strands
    * @beta
    * @param {Function} callback A function building a p5.strands shader.
+   * @param {Object} [scope] An optional scope object passed to .modify().
    * @returns {p5.Shader} The normal shader.
    */
   /**
    * @method buildNormalShader
    * @param {Object} hooks An object specifying p5.strands hooks in GLSL.
+   * @param {Object} [scope] An optional scope object passed to .modify().
    * @returns {p5.Shader} The normal shader.
    */
   fn.buildNormalShader = function (cb, scope) {
@@ -1940,11 +1946,13 @@ function material(p5, fn) {
    * @submodule p5.strands
    * @beta
    * @param {Function} callback A function building a p5.strands shader.
+   * @param {Object} [scope] An optional scope object passed to .modify().
    * @returns {p5.Shader} The color shader.
    */
   /**
    * @method buildColorShader
    * @param {Object} hooks An object specifying p5.strands hooks in GLSL.
+   * @param {Object} [scope] An optional scope object passed to .modify().
    * @returns {p5.Shader} The color shader.
    */
   fn.buildColorShader = function (cb, scope) {
@@ -2195,11 +2203,13 @@ function material(p5, fn) {
    * @submodule p5.strands
    * @beta
    * @param {Function} callback A function building a p5.strands shader.
+   * @param {Object} [scope] An optional scope object passed to .modify().
    * @returns {p5.Shader} The stroke shader.
    */
   /**
    * @method buildStrokeShader
    * @param {Object} hooks An object specifying p5.strands hooks in GLSL.
+   * @param {Object} [scope] An optional scope object passed to .modify().
    * @returns {p5.Shader} The stroke shader.
    */
   fn.buildStrokeShader = function (cb, scope) {

test/unit/webgl/p5.Shader.scope.js

@@ -0,0 +1,25 @@
+import p5 from '../../../src/app.js';
+
+suite('p5.Shader', function() {
+  suite('buildMaterialShader scope forwarding', function() {
+    test('forwards scope to modify in instance mode', function(done) {
+      new p5((sketch) => {
+        sketch.setup = function() {
+          sketch.createCanvas(10, 10, sketch.WEBGL);
+
+          const scope = { sketch };
+          let receivedSketch = null;
+
+          sketch.buildMaterialShader(function({ sketch: s }) {
+            receivedSketch = s;
+          }, scope);
+
+          assert.strictEqual(receivedSketch, sketch);
+
+          sketch.remove();
+          done();
+        };
+      });
+    });
+  });
+});