新增: 壁纸切换（主题/本地图片/Bing/纯色渐变）

web/themes/aurora.html

@@ -0,0 +1,77 @@
+<canvas id="canvas" style="position:fixed;top:0;left:0;width:100%;height:100%;z-index:1;"></canvas>
+<script>
+var canvas = document.getElementById('canvas');
+var gl = canvas.getContext('webgl');
+
+function resizeCanvas() {
+  canvas.width = window.innerWidth;
+  canvas.height = window.innerHeight;
+  gl.viewport(0, 0, canvas.width, canvas.height);
+}
+resizeCanvas();
+window.addEventListener('resize', resizeCanvas);
+
+var vsSource = 'attribute vec4 aVertexPosition;void main(){gl_Position=aVertexPosition;}';
+var fsSource = `
+  precision mediump float;
+  uniform float uTime;
+  uniform vec2 uResolution;
+  void main() {
+    vec2 uv=gl_FragCoord.xy/uResolution.xy;
+    vec3 c1=vec3(0.1,0.4,0.8);
+    vec3 c2=vec3(0.4,0.2,0.8);
+    vec3 c3=vec3(0.1,0.6,0.4);
+    float w1=sin(uv.x*3.0+uTime*0.5)*0.5+0.5;
+    float w2=sin(uv.x*4.0+uTime*0.3+uv.y*2.0)*0.5+0.5;
+    float w3=sin(uv.x*2.0+uTime*0.7+uv.y*3.0)*0.5+0.5;
+    float d=uv.y*2.0-1.0;
+    float g=exp(-d*d*2.0);
+    vec3 a=(c1*w1+c2*w2+c3*w3)*g*0.6;
+    vec3 b=mix(vec3(0.02,0.02,0.08),vec3(0.05,0.05,0.15),uv.y);
+    gl_FragColor=vec4(b+a,1.0);
+  }
+`;
+
+function loadShader(gl,type,source){
+  var s=gl.createShader(type);
+  gl.shaderSource(s,source);
+  gl.compileShader(s);
+  if(!gl.getShaderParameter(s,gl.COMPILE_STATUS)){gl.deleteShader(s);return null;}
+  return s;
+}
+
+var vs=loadShader(gl,gl.VERTEX_SHADER,vsSource);
+var fs=loadShader(gl,gl.FRAGMENT_SHADER,fsSource);
+var prog=gl.createProgram();
+gl.attachShader(prog,vs);
+gl.attachShader(prog,fs);
+gl.linkProgram(prog);
+
+var posLoc=gl.getAttribLocation(prog,'aVertexPosition');
+var timeLoc=gl.getUniformLocation(prog,'uTime');
+var resLoc=gl.getUniformLocation(prog,'uResolution');
+
+var posBuf=gl.createBuffer();
+gl.bindBuffer(gl.ARRAY_BUFFER,posBuf);
+gl.bufferData(gl.ARRAY_BUFFER,new Float32Array([-1,1,1,1,-1,-1,1,-1]),gl.STATIC_DRAW);
+
+var startTime=Date.now();
+var FPS=15,lastFrame=0;
+
+function render(ts){
+  requestAnimationFrame(render);
+  if(ts-lastFrame<1000/FPS)return;
+  lastFrame=ts;
+  gl.viewport(0,0,canvas.width,canvas.height);
+  gl.clearColor(0,0,0,1);
+  gl.clear(gl.COLOR_BUFFER_BIT);
+  gl.useProgram(prog);
+  gl.enableVertexAttribArray(posLoc);
+  gl.bindBuffer(gl.ARRAY_BUFFER,posBuf);
+  gl.vertexAttribPointer(posLoc,2,gl.FLOAT,false,0,0);
+  gl.uniform1f(timeLoc,(Date.now()-startTime)/1000);
+  gl.uniform2f(resLoc,canvas.width,canvas.height);
+  gl.drawArrays(gl.TRIANGLE_STRIP,0,4);
+}
+requestAnimationFrame(render);
+</script>