1. 程式人生 > >[Unity3D]Shader程式設計之貼圖切換

[Unity3D]Shader程式設計之貼圖切換

本shader實現基於世界座標的貼圖置換效果。

效果如下:
這裡寫圖片描述

設定面板如下:
這裡寫圖片描述

可在面板上設定切換方向,與切換物件,及其切換速度。

shader實現如下:

Shader "XM/Effect/SwapTexture" {
    Properties {
        _Color ("Color", Color) = (1,1,1,1)
        _MainTex ("Albedo (RGB)", 2D) = "white" {}
        _TargetTex ("Target Tex", 2D) = "white" {}//目標貼圖
        [KeywordEnum(Up, Down, Left, Right, Forward, Back)] _mode ("Mode"
, Int) = 0//切換方向 _SwapBlend ("Blend", Range(0,1)) = 0//0-1混合值 _SwapMin("Min Value", Float) = 0//最小世界座標 _SwapMax("Max Value", Float) = 0//最大世界座標 _Glossiness ("Smoothness", Range(0,1)) = 0.5 _Metallic ("Metallic", Range(0,1)) = 0.0 } SubShader { Tags { "RenderType"
="Opaque" } LOD 200 CGPROGRAM // Physically based Standard lighting model, and enable shadows on all light types #pragma surface surf Standard fullforwardshadows vertex:vert // Use shader model 3.0 target, to get nicer looking lighting #pragma target 3.0 sampler2D _MainTex; sampler2D _TargetTex; struct
Input { float2 uv_MainTex; float3 worldPos; }; half _mode; half _SwapBlend; float _SwapMin; float _SwapMax; half _Glossiness; half _Metallic; fixed4 _Color; void vert (inout appdata_full v, out Input o) { UNITY_INITIALIZE_OUTPUT(Input,o); } void surf (Input IN, inout SurfaceOutputStandard o) { half useTarget = 0; float targetValue = 0; switch(_mode)//模式選擇 { case 0://up targetValue = (_SwapMax - _SwapMin) * _SwapBlend + _SwapMin; useTarget = IN.worldPos.y > targetValue?0:1; break; case 1://down targetValue = (_SwapMax - _SwapMin) * (1 - _SwapBlend) + _SwapMin; useTarget = IN.worldPos.y < targetValue?0:1; break; case 2://left targetValue = (_SwapMax - _SwapMin) * (1 - _SwapBlend) + _SwapMin; useTarget = IN.worldPos.x < targetValue?0:1; break; case 3://right targetValue = (_SwapMax - _SwapMin) * _SwapBlend + _SwapMin; useTarget = IN.worldPos.x > targetValue?0:1; break; case 4://forward targetValue = (_SwapMax - _SwapMin) * _SwapBlend + _SwapMin; useTarget = IN.worldPos.z > targetValue?0:1; break; case 5://back targetValue = (_SwapMax - _SwapMin) * (1 - _SwapBlend) + _SwapMin; useTarget = IN.worldPos.z < targetValue?0:1; break; } // Albedo comes from a texture tinted by color fixed4 c; if(useTarget == 1) { c = tex2D (_TargetTex, IN.uv_MainTex); } else { c = tex2D (_MainTex, IN.uv_MainTex); } c *= _Color; o.Albedo = c.rgb; // Metallic and smoothness come from slider variables o.Metallic = _Metallic; o.Smoothness = _Glossiness; o.Alpha = c.a; } ENDCG } FallBack "Diffuse" }

配合使用的指令碼如下:

using System;
using System.Collections;
using UnityEngine;

namespace XM.Effect
{
    public class SwapTexture : MonoBehaviour
    {
        public enum SwapDirection
        {
            Up,
            Down,
            Left,
            Right,
            Forward,
            Back
        }

        public Shader _shader;//"XM/Effect/SwapTexture” shader
        public SwapDirection _swapDir;//切換方向
        public Renderer _target;//目標物件
        [Range(0, 1)]
        public float _speed;//速度

        private Material _matOld;
        private Material _matNew;

        public void Swap(Texture tex, Action<bool> onComplete)
        {
            if (_matOld != null)
            {
                StopAllCoroutines();
                if (null != onComplete)
                {
                    onComplete(false);
                }

                _target.material = _matOld;
            }

            _matOld = _target.material;

            _matNew = new Material(_shader);
            _matNew.SetTexture("_MainTex", _target.material.GetTexture("_MainTex"));
            _matNew.SetTexture("_TargetTex", tex);
            _matNew.SetInt("_mode", (int)_swapDir);
            _matNew.SetFloat("_SwapBlend", 0);

            StartCoroutine("_StartChange", onComplete);
        }

        private IEnumerator _StartChange(Action<bool> onComplete)
        {
            float deltaVal = 0;

            _target.material = _matNew;

            Vector3 vtMin;
            Vector3 vtMax;
            float minVal = 0;
            float maxVal = 0;

            while (deltaVal != 1)
            {
                vtMin = _target.bounds.min;
                vtMax = _target.bounds.max;

                switch (_swapDir)
                {
                    case SwapDirection.Up:
                    case SwapDirection.Down:
                        minVal = vtMin.y;
                        maxVal = vtMax.y;
                        break;
                    case SwapDirection.Left:
                    case SwapDirection.Right:
                        minVal = vtMin.x;
                        maxVal = vtMax.x;
                        break;
                    case SwapDirection.Forward:
                    case SwapDirection.Back:
                        minVal = vtMin.z;
                        maxVal = vtMax.z;
                        break;
                }

                minVal -= 0.01f;
                maxVal += 0.01f;

                _matNew.SetFloat("_SwapMin", minVal);
                _matNew.SetFloat("_SwapMax", maxVal);

                deltaVal = Mathf.Clamp01(deltaVal + _speed * Time.deltaTime);
                _matNew.SetFloat("_SwapBlend", deltaVal);
                yield return null;
            }

            _matOld.SetTexture("_MainTex", _matNew.GetTexture("_TargetTex"));
            _target.material = _matOld;

            _matNew = null;
            _matOld = null;

            if (null != onComplete)
            {
                onComplete(true);
            }
        }

        public void OnDrawGizmos()
        {
            if (_target != null)
            {
                Gizmos.DrawWireCube(_target.bounds.center, _target.bounds.size);
                Gizmos.DrawWireSphere(_target.bounds.min, 0.1f);
                Gizmos.DrawWireSphere(_target.bounds.max, 0.1f);
            }
        }

        //test
        public Texture testTex;
        private void OnGUI()
        {
            if (GUILayout.Button("SwapTexture"))
            {
                Swap(testTex, (t) =>
                {
                    Debug.Log("Swap>" + t);
                });
            }
        }
        //
    }
}

這裡寫圖片描述