矩阵变换_C#_解释矩阵变换旋转原理

C#

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class MVPTransform : MonoBehaviour {

    // Use this for initialization
    void Start () {
        
    }
    
    // Update is called once per frame
    void Update () {
        Matrix4x4 RM =new Matrix4x4();
        RM[0,0] =Mathf.Cos (Time.realtimeSinceStartup);
        RM[0,2] =Mathf.Sin(Time.realtimeSinceStartup);
        RM[1,1] = 1;

        RM[2,0] =-Mathf.Sin (Time.realtimeSinceStartup);
        RM[2,2] =Mathf.Cos(Time.realtimeSinceStartup);
        RM[3,3] = 1;



        Matrix4x4 mvp =  Camera.main.projectionMatrix* Camera.main.worldToCameraMatrix *transform.localToWorldMatrix*RM ;
        GetComponent<Renderer>().material.SetMatrix("mvp",mvp);
        
    
        
    }
}

shader

Shader "Unlit/V2f"
{
    SubShader{
            pass{
                
                CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #include "UnityCG.cginc"
            float4x4 mvp;


            struct a2v
            {
                 float4 vertex : POSITION;
                float3 normal : NORMAL;
                float4 texcoord : TEXCOORD0;
            };
            
            struct v2f {
                
                float4 pos:POSITION;
            };          

            v2f vert(a2v v)
            {
                v2f o;
                //o.pos = UnityObjectToClipPos(v.vertex);       //核心： 矩阵变换 当前模型*视图*投影矩阵
                o.pos= mul(mvp,v.vertex);
                return o;

            }   

            fixed frag():SV_TARGET
            {
                return fixed4 (1,1,1,1);

            }

            ENDCG
 
            }



    }
    
}