add primitive WebGL template from Mozilla docs

www/init-buffers.js

@@ -0,0 +1,29 @@
+function initBuffers(gl) {
+  const positionBuffer = initPositionBuffer(gl);
+
+  return {
+    position: positionBuffer,
+  };
+}
+
+function initPositionBuffer(gl) {
+  // Create a buffer for the square's positions.
+  const positionBuffer = gl.createBuffer();
+
+  // Select the positionBuffer as the one to apply buffer
+  // operations to from here out.
+  gl.bindBuffer(gl.ARRAY_BUFFER, positionBuffer);
+
+  // Now create an array of positions for the square.
+  const positions = [1.0, 1.0, -1.0, 1.0, 1.0, -1.0, -1.0, -1.0];
+
+  // Now pass the list of positions into WebGL to build the
+  // shape. We do this by creating a Float32Array from the
+  // JavaScript array, then use it to fill the current buffer.
+  gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(positions), gl.STATIC_DRAW);
+
+  return positionBuffer;
+}
+
+export { initBuffers };
+