WIP attempt to use end portal shader

Using shader-web-background
Got demotivated when it doesn't work locally due to cross-site restrictions

http/poem.html

@@ -5,6 +5,65 @@
         <meta name="viewport" content="width=device-width, initial-scale=1.0"/>
         <meta name="theme-color" content="#02060D"/>
         <title>End Poem</title>
+        <script src="https://xemantic.github.io/shader-web-background/dist/shader-web-background.min.js"></script>
+        <script type="x-shader/x-fragment" id="image">
+            precision highp float;
+
+            uniform sampler2D Sampler0;
+            uniform sampler2D Sampler1;
+
+            void main() {
+
+            }
+        </script>
+        <script>
+        const loadImage = (src) => new Promise((resolve, reject) => {
+              let img = new Image();
+              img.crossOrigin = "";
+              img.onload = () => resolve(img);
+              img.onerror = () => {
+                reject(new Error("Failed to load image from: " + src));
+              };
+              img.src = src;
+            });
+          shaderWebBackground.shade({
+              onInit: (ctx) => {
+                      loadImage("end_portal.png")
+                        .then(image => {
+                          const gl = ctx.gl;
+                          const texture = gl.createTexture();
+                          gl.bindTexture(gl.TEXTURE_2D, texture);
+                          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);
+                          gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
+                          gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, image);
+                          gl.bindTexture(gl.TEXTURE_2D, null);
+                          ctx.Sampler0 = texture;
+                        });
+                      loadImage("end_sky.png")
+                        .then(image => {
+                          const gl = ctx.gl;
+                          const texture = gl.createTexture();
+                          gl.bindTexture(gl.TEXTURE_2D, texture);
+                          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);
+                          gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
+                          gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, image);
+                          gl.bindTexture(gl.TEXTURE_2D, null);
+                          ctx.Sampler0 = texture;
+                        });
+                    },
+            shaders: {
+              image: {
+                  uniforms: {
+
+                  }
+              }
+            }
+          });
+        </script>
         <style>
             body {
                 color: white;