Unity shader实现*放大缩小效果

本文实例为大家分享了unity shader实现*放大缩小效果的具体代码，供大家参考，具体内容如下

代码：

以下实现的shader代码：

shader "hidden/wave"
{
 properties
 {
 _maintex ("texture", 2d) = "white" {}
 _wavewidth("wave width",float) = 0.5
 _centerx("centerx",float)=0.5
 _centery("centery",float)=0.5
 }
 subshader
 {
 // no culling or depth
 cull off zwrite off ztest always

 pass
 {
  cgprogram
  #pragma vertex vert
  #pragma fragment frag
  
  #include "unitycg.cginc"

  struct appdata
  {
  float4 vertex : position;
  float2 uv : texcoord0;
  };

  struct v2f
  {
  float2 uv : texcoord0;
  float4 vertex : sv_position;
  };


  float _wavewidth;
  float _centerx;
  float _centery;
  v2f vert (appdata v)
  {
  v2f o;
  o.vertex = unityobjecttoclippos(v.vertex);
  o.uv = v.uv;
  return o;
  }
  
  sampler2d _maintex;

  fixed4 frag (v2f i) : sv_target
  {
  float2 center=float2(_centerx,_centery);
  float2 distance= center - i.uv;
  float x=center.x+ center.x*(-distance.x/center.x) *(1-_wavewidth);
  float y=center.y+ center.y*(-distance.y/center.y) *(1-_wavewidth);
  float2 uv = float2(x,y);
  return tex2d(_maintex, uv);  
  }
  endcg
 }
 }
}

主要的内容还是在frag中。

下面是挂在摄像机上的脚本：

using system.collections;
using system.collections.generic;
using unityengine;
 
public class wavecreame : monobehaviour {
 
 
  public shader waveshader = null;
  [range(0.0f,1f)]
  public float wavewidth = 0.3f;
  private material m_wavematerial = null;
  private float m_centerx = 0.5f;
  private float m_ctentery = 0.5f;
 // use this for initialization
 void start () {
    m_wavematerial = new material(waveshader);
 }
 
 // update is called once per frame
 void update () {
    vector3 pos = input.mouseposition;
    m_centerx = pos.x / screen.width;
    m_ctentery = pos.y / screen.height;
    if (input.getmousebutton(0)) {
      wavewidth += time.deltatime * 0.5f;
    }
    if (input.getmousebutton(1))
    {
      wavewidth -= time.deltatime * 0.5f;
    }
  }
 
  private void onrenderimage(rendertexture source, rendertexture destination)
  {
    if (waveshader == null || m_wavematerial == null) return;
    m_wavematerial.setfloat("_wavewidth", wavewidth);
    m_wavematerial.setfloat("_centerx", m_centerx);
    m_wavematerial.setfloat("_centery", m_ctentery);
    graphics.blit(source, destination, m_wavematerial);
  }
}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。