背景 概:早在今年上半年看了素晴的剧场版红传说后,对惠惠的角色喜爱更多了几分(划掉),对爆裂魔法的喜爱又多了几分。嗯,而刚好在不久后的一次与室友的项目合作中,我主担了特效师的位置,当时学了shadergraph,然后感觉无所不能之后决定去搓一手爆裂魔法,于是新红魔族爆裂魔法选手诡奇他来了。不过由于当时技术力的原因,只做了一个简易的魔法阵展开。在多个月以后的最近,我又重拾了爆裂魔法项目,且前不久看到了b站大佬(啊,也不能这么说,好多站点都有他的号)搓的爆裂魔法,产生了一些灵感,在加之技术力的提升,最近搓了起来。这边贴一下大佬的视频链接:大佬的爆裂魔法
技术涉及 概:本篇主要讲如何实现爆裂魔法场景效果中的彩色星星这个东西,以及手搓了一个简易的发射器。涉及到的技术主要有:shader,mesh绘制,c#对游戏物体的运用。
以上是关于本篇实现的效果截图展示,还原度一般,仍存在一些问题,但最终的效果基本是可以用了。感兴趣的继续往下看。
关于这个mesh我想到俩种画法,一种是单层双面绘制,一种是双层绘制,单层的话只需要9个顶点,按照不同方向画俩便三角形就可以,双层的话需要至少14个顶点,且要控制好厚度,很麻烦,于是出于懒鬼本懒得缘故,我啪一下就选择了单层双面绘制。
对照上图可以得出具体的9个顶点的位置,有关2 4 6 8这四个点,我给其初始位置设置在13 45 57 71这些连线的中点上,也就是坐标都是0.5相关,所有顶点的z我均按照0走了,保证其绘制出的mesh在一个平面上。
综上所述,初始顶点坐标信息如下:
PosList = new Vector3[] {
new Vector3(0,0,0),new Vector3(0,1,0),new Vector3(-0.5f,0.5f,0),
new Vector3(-1,0,0),new Vector3(-0.5f,-0.5f,0),new Vector3(0,-1,0),
new Vector3(0.5f,-0.5f,0),new Vector3(1,0,0),new Vector3(0.5f,0.5f,0)
};
mesh.triangles = new int[] {
2, 1, 8, 2, 8, 0, 3, 2, 4, 2, 0, 4,
4, 0, 6, 4, 6, 5, 6, 8, 7, 6, 0, 8,
8, 1, 2, 0, 8, 2, 4, 2, 3, 4, 0, 2,
6, 0, 4, 5, 6, 4, 7, 8, 6, 8, 0, 6
};
private void Mesh_Update()
{
//mesh更新方法
//克隆顶点基础坐标
Vector3[] pos = new Vector3[9];
for(int i = 0;i<9;i++)
{
pos[i] = PosList[i];
}
//对部分顶点进行偏移
pos[2] *= Mul_width;
pos[4] *= Mul_width;
pos[6] *= Mul_width;
pos[8] *= Mul_width;
mesh.vertices = pos;
//uv计算
Vector2[] uv = new Vector2[9];
for (int i = 0; i < 9; i++)
{
//通过模型空间下的顶点坐标xy去计算uv坐标下的uv
uv[i].x = (pos[i].x+1)/2;
uv[i].y = (pos[i].y+1)/2;
}
mesh.uv = uv;
}
Shader "Custom/MyShader/Stars"
{
Properties
{
_Minus ("Minus", Range(0,1)) = 0
[HDR]_Color_Rainbow ("Color_Rainbow", Color) = (1,1,1,0)
[HDR]_Color_BG ("Color_BG", Color) = (1,1,1,0)
_MainTex ("MainTex", 2D) = "white" {
}
_RainbowTex ("RainbowTex", 2D) = "white" {
}
}
SubShader
{
pass
{
Tags{
"LightMode"="ForwardBase" }
CGPROGRAM
#pragma vertex ver_tex
#pragma fragment Pixel
#include "Lighting.cginc"
struct vertexInput{
float4 pos : POSITION;
float4 uv : TEXCOORD0;
};
struct vertexOutput{
float4 pos : SV_POSITION;
float2 uv : TEXCOORD0;
};
sampler2D _RainbowTex;
fixed4 _Color_Rainbow;
vertexOutput ver_tex(vertexInput v){
vertexOutput r;
//描边外扩1.2倍
v.pos*=1.2;
//之后转换到裁剪空间传入下级
r.pos = UnityObjectToClipPos(v.pos);
//uv流动
r.uv = v.uv;
r.uv.x += _Time.z*0.2;
return r;
}
fixed4 Pixel(vertexOutput i):SV_TARGET{
fixed3 col = tex2D(_RainbowTex,i.uv).xyz;
return _Color_Rainbow*fixed4(col,1);
}
ENDCG
}
pass
{
Tags{
"LightMode"="ForwardBase" }
CGPROGRAM
#pragma vertex ver_tex
#pragma fragment Pixel
#include "Lighting.cginc"
struct vertexInput{
float4 pos : POSITION;
float4 uv : TEXCOORD0;
};
struct vertexOutput{
float4 pos : SV_POSITION;
float2 uv : TEXCOORD0;
};
sampler2D _MainTex;
fixed4 _Color_BG;
fixed _Minus;
vertexOutput ver_tex(vertexInput v){
vertexOutput r;
r.pos = UnityObjectToClipPos(v.pos);
//uv流动
r.uv = v.uv;
r.uv.y+=_Time.z*0.15;
//z增大深度减小
r.pos.z+=1;
return r;
}
fixed4 Pixel(vertexOutput i):SV_TARGET{
fixed3 col1 = tex2D(_MainTex,i.uv).xyz;
return _Color_BG*fixed4(col1,0);
}
ENDCG
}
}
FallBack "Diffuse"
}
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class StarsMesh : MonoBehaviour
{
Mesh mesh;
public float Mul_width = 0;
public float Rotation_Z_Speed = 0;
public float Upper_Limit = 0.7f;
public float Lower_Limit = 0.1f;
public float Width_Speed = 0.1f;
public Vector3 Move_Vector = new Vector3(0, 0, 0);
public float Life_Cycle = 0;
private float Width_A = 0; //粗细变化的插值参照
private bool Width_B = true; //粗细变化的方向判断
private float Old_Mul_width = 0;
private Vector3[] PosList;
void Start()
{
//mesh初始化
mesh = new Mesh();
PosList = new Vector3[] {
new Vector3(0,0,0),new Vector3(0,1,0),new Vector3(-0.5f,0.5f,0),
new Vector3(-1,0,0),new Vector3(-0.5f,-0.5f,0),new Vector3(0,-1,0),
new Vector3(0.5f,-0.5f,0),new Vector3(1,0,0),new Vector3(0.5f,0.5f,0)
};
Mesh_Update();
//三角绘制,由于三角数组固定,所以不需要放在mesh更新方法里,仅执行一次以节省性能
mesh.triangles = new int[] {
2, 1, 8, 2, 8, 0, 3, 2, 4, 2, 0, 4,
4, 0, 6, 4, 6, 5, 6, 8, 7, 6, 0, 8,
8, 1, 2, 0, 8, 2, 4, 2, 3, 4, 0, 2,
6, 0, 4, 5, 6, 4, 7, 8, 6, 8, 0, 6
};
GetComponent<MeshFilter>().mesh = mesh;
//按照生命周期销毁
Destroy(this.gameObject, Life_Cycle);
}
private void Update()
{
#region 粗细变化
if (Width_B)
{
Width_A += Time.deltaTime * Width_Speed;
if(Width_A>=1)
{
Width_B = false;
}
}
else
{
Width_A -= Time.deltaTime * Width_Speed;
if (Width_A <= 0)
{
Width_B = true;
}
}
Mul_width = Mathf.Lerp(Lower_Limit, Upper_Limit, Width_A);
Mesh_Update();
#endregion
//旋转
transform.Rotate(new Vector3(0, 0, Rotation_Z_Speed));
//移动
transform.position += Move_Vector * Time.deltaTime;
}
private void Mesh_Update()
{
//mesh更新方法
//克隆顶点基础坐标
Vector3[] pos = new Vector3[9];
for(int i = 0;i<9;i++)
{
pos[i] = PosList[i];
}
//对部分顶点进行偏移
pos[2] *= Mul_width;
pos[4] *= Mul_width;
pos[6] *= Mul_width;
pos[8] *= Mul_width;
mesh.vertices = pos;
//uv计算
Vector2[] uv = new Vector2[9];
for (int i = 0; i < 9; i++)
{
//通过模型空间下的顶点坐标xy去计算uv坐标下的uv
uv[i].x = (pos[i].x+1)/2;
uv[i].y = (pos[i].y+1)/2;
}
mesh.uv = uv;
}
}
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Launcher : MonoBehaviour
{
public GameObject Stars;
//对星星的随机参数界限设定
public Vector3 StartPosMin;
public Vector3 StartPosMax;
public Vector3 StartRotMin;
public Vector3 StartRotMax;
public Vector3 StartMoveMin;
public Vector3 StartMoveMax;
public float Start_RotZ_Min;
public float Start_RotZ_Max;
public float Start_Width_Speed_Min;
public float Start_Width_Speed_Max;
public float Start_Life_Cycle_Min;
public float Start_Life_Cycle_Max;
public float Start_Scale_Min;
public float Start_Scale_Max;
public float MoveSpeed = 0;
public float CreateSpeed = 0;
public float Life_Cycle = 0;
private float CreateTop = 1000;
public float CreateNow = 0;
// Start is called before the first frame update
void Start()
{
Destroy(this.gameObject, Life_Cycle);
CreateTop = 1000;
CreateNow = 0;
}
// Update is called once per frame
void Update()
{
CreateNow += CreateSpeed * Time.deltaTime;
if (CreateNow >= CreateTop)
{
Creat_Stars();
CreateNow = 0;
}
}
private void Creat_Stars()
{
//生成随机初始化参数
//生成坐标
Vector3 pos = new Vector3(Random.Range(StartPosMin.x, StartPosMax.x),
Random.Range(StartPosMin.y, StartPosMax.y), Random.Range(StartPosMin.z, StartPosMax.z));
//生成旋转
Vector3 rot = new Vector3(Random.Range(StartRotMin.x, StartRotMax.x),
Random.Range(StartRotMin.y, StartRotMax.y), Random.Range(StartRotMin.z, StartRotMax.z));
//移动向量
Vector3 move = new Vector3(Random.Range(StartMoveMin.x, StartMoveMax.x),
Random.Range(StartMoveMin.y, StartMoveMax.y), Random.Range(StartMoveMin.z, StartMoveMax.z));
//平转速度
float rotZ = Random.Range(Start_RotZ_Min, Start_RotZ_Max);
//宽度变化速度
float width_speed = Random.Range(Start_Width_Speed_Min, Start_Width_Speed_Max);
//生命周期
float life_c = Random.Range(Start_Life_Cycle_Min, Start_Life_Cycle_Max);
//整体缩放
float scale = Random.Range(Start_Scale_Min, Start_Scale_Max);
GameObject star = Instantiate(Stars, pos, Quaternion.Euler(rot));
StarsMesh starsmesh = star.GetComponent<StarsMesh>();
starsmesh.Move_Vector = move * MoveSpeed;
starsmesh.Width_Speed = width_speed;
starsmesh.Rotation_Z_Speed = rotZ;
starsmesh.Life_Cycle = life_c;
star.transform.localScale *= scale;
}
}