dc-sdk/modules/material/shader/circle/CircleRotateMaterial.glsl

uniform vec4 color;
uniform sampler2D image;
czm_material czm_getMaterial(czm_materialInput materialInput){
  czm_material material = czm_getDefaultMaterial(materialInput);
  vec2 st = materialInput.st;
  vec2 center = st - vec2(0.5,0.5);
  float time = -czm_frameNumber * 3.1415926 / 180.;
  float sin_t = sin(time);
  float cos_t = cos(time);
  vec2 center_rotate = vec2(center.s * cos_t - center.t * sin_t + 0.5,center.s * sin_t + center.t * cos_t + 0.5);
  vec4 colorImage = texture2D(image,center_rotate);
  vec3 temp = colorImage.rgb * color.rgb;
  temp *= color.a;
  material.diffuse = temp;
  float length = 2. - length(center) / 0.5;
  material.alpha = colorImage.a * pow(length, 0.5);
  return material;
}