Add Shader#setUniform and ShaderQuadConfig#initialUniforms.

Author: BenjaminDRichards

changelog/4.0/CHANGELOG-v4.0-rc.2.md

@@ -5,6 +5,8 @@ Updates since RC1:
 ## New Features
 
 - `RenderConfig#renderNodes` allows you to add render nodes at game boot.
+- `ShaderQuadConfig#initialUniforms` lets you initialize a Shader with uniforms on creation.
+- `Shader#setUniform(name, value)` lets you set shader program uniforms just once, instead of putting them all into the `setupUniforms()` method, where some uniforms might be set redundantly after init. This wraps `Shader#renderNode.programManager.setUniform`.
 
 ## Changes
 
@@ -17,3 +19,5 @@ Updates since RC1:
 - Add typedefs for the `{ internal, external }` structure of `Camera#filters` (and `GameObject#filters`).
 - Fix `FilterList#addMask` docs.
 - In Layer and Container objects, use that object's children for the `displayList` passed to `RenderWebGLSteps`.
+- Fix positioning of Group members and offset objects in `DynamicTexture#draw`.
+- Fix Shadow filter direction.

src/gameobjects/shader/Shader.js

@@ -157,6 +157,12 @@ var Shader = new Class({
             this.renderNode.updateShaderConfig = config.updateShaderConfig;
         }
 
+        var initialUniforms = GetFastValue(config, 'initialUniforms', {});
+        Object.entries(initialUniforms).forEach(function (entry)
+        {
+            this.setUniform(entry[0], entry[1]);
+        }, this);
+
         /**
          * The drawing context containing the framebuffer and texture that the shader is rendered to.
          * This is only set if the shader is rendering to a texture.
@@ -255,7 +261,7 @@ var Shader = new Class({
      * will modify the original.
      *
      * It's generally better to use the `setupUniforms` function in the
-     * shader configuration object to set the uniform values.
+     * shader configuration object to set uniform values on changing uniforms.
      * This method is provided in the spirit of reading back the values.
      *
      * @method Phaser.GameObjects.Shader#getUniform
@@ -268,6 +274,26 @@ var Shader = new Class({
         return this.renderNode.programManager.uniforms[name];
     },
 
+    /**
+     * Set the value of a uniform in the shader.
+     * This value is actually copied to all shaders that use it.
+     *
+     * It's generally better to use the `setupUniforms` function in the
+     * shader configuration object to set uniform values on changing uniforms.
+     * Use this method to set uniforms just once.
+     *
+     * @method Phaser.GameObjects.Shader#setUniform
+     * @since 4.0.0
+     * @param {string} name - The name of the uniform to set.
+     * @param {any} value - The value to set the uniform to.
+     * @return {this}
+     */
+    setUniform: function (name, value)
+    {
+        this.renderNode.programManager.setUniform(name, value);
+        return this;
+    },
+
     /**
      * Set the textures that the shader uses.
      *