//溶解特效

 CCEffect %{
  techniques:
  - passes:
    - vert: vs
      frag: fs
      blendState:
        targets:
        - blend: true
      rasterizerState:
        cullMode: none
      properties:
        texture: { value: white }
        u_time: { value: 1.0 }
}%

CCProgram vs %{
	#include <cc-global>
	precision highp float;
    in vec3 a_position;
    in vec2 a_uv0;
    out vec2 uv0;
    void main () {
        gl_Position = cc_matViewProj * vec4(a_position, 1);
        uv0 = a_uv0;
    }
}%

CCProgram fs %{
	precision highp float;		//定义高精度
	uniform sampler2D texture;	//纹理
	uniform ARGS {
		//时间 根据时间计算需要丢弃的像素颜色值范围，也就是溶解的范围
		float u_time;
	};
	in vec2 uv0;

	void main()
	{
		float time = u_time;
		vec4 c = texture2D(texture,uv0);
		float height = c.g;
		if(height < time)
		{
			//丢弃像素，相当于溶解效果
			discard;
		}
		if(height < time + 0.1) {
			//这里可以对溶解边缘进行一些处理，比如透明度减少等
			c.a = c.a-0.1;
		}
		//给片元（像素）赋值
		gl_FragColor = c;
	}
}%