unity shader 實現自由放大縮小效果
阿新 • • 發佈:2019-02-12
以下實現的shader程式碼:
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 } } }
主要的內容還是在frag中。
下面是掛在攝像機上的指令碼:
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); } }