我正在尝试使用Shells技术在Unity中实现毛发.Fins技术是故意遗漏的,因为我希望它在低端手机(主要是Android设备)上运行,并且需要OpenGL ES 3.0及更高版本,而Shells技术只需要OpenGL ES 2.0.
有一个基于XNA的Shell技术的例子,我试图将它移植到Unity但它无法工作.这是XNA项目的文章.
在XNA着色器:
float4x4 World;
float4x4 View;
float4x4 Projection;
float CurrentLayer; //value between 0 and 1
float MaxHairLength; //maximum hair length
texture FurTexture;
sampler FurSampler = sampler_state
{
Texture = (FurTexture);
MinFilter = Point;
MagFilter = Point;
MipFilter = Point;
AddressU = Wrap;
AddressV = Wrap;
};
struct VertexShaderInput
{
float3 Position : POSITION0;
float3 Normal : NORMAL0;
float2 TexCoord : TEXCOORD0;
};
struct VertexShaderOutput
{
float4 Position : POSITION0;
float2 TexCoord : TEXCOORD0;
};
VertexShaderOutput FurVertexShader(VertexShaderInput input)
{
VertexShaderOutput output;
float3 pos;
pos = input.Position + input.Normal * MaxHairLength * CurrentLayer;
float4 worldPosition = mul(float4(pos,1), World);
float4 viewPosition = mul(worldPosition, View);
output.Position = mul(viewPosition, Projection);
output.TexCoord = input.TexCoord;
return output;
}
float4 FurPixelShader(VertexShaderOutput input) : COLOR0
{
return tex2D(FurSampler, input.TexCoord);
}
technique Fur
{
pass Pass1
{
AlphaBlendEnable = true;
SrcBlend = SRCALPHA;
DestBlend = INVSRCALPHA;
CullMode = None;
VertexShader = compile vs_2_0 FurVertexShader();
PixelShader = compile ps_2_0 FurPixelShader();
}
}
控制着色器的XNA C#脚本:
///
/// This is the main type for your game
///
public class Game1 : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
public Game1()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
}
//simple camera for use in the game
Camera camera;
//texture containing fur data
Texture2D furTexture;
//effect for fur shaders
Effect furEffect;
//number of layers of fur
int nrOfLayers = 60;
//total length of the hair
float maxHairLength = 2.0f;
//density of hair
float density = 0.2f;
Texture2D furColorTexture;
//movement vectors
Vector3 gravity = new Vector3(0, -1.0f, 0);
Vector3 forceDirection = Vector3.Zero;
//final displacement for hair
Vector3 displacement;
///
/// Allows the game to perform any initialization it needs to before starting to run.
/// This is where it can query for any required services and load any non-graphic
/// related content. Calling base.Initialize will enumerate through any components
/// and initialize them as well.
///
protected override void Initialize()
{
// TODO: Add your initialization logic here
camera = new Camera(this);
Components.Add(camera);
base.Initialize();
}
///
/// LoadContent will be called once per game and is the place to load
/// all of your content.
///
protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
spriteBatch = new SpriteBatch(GraphicsDevice);
//generate the geometry
GenerateGeometry();
//load the effect
furEffect = Content.Load("FurEffect");
//create the texture
furTexture = new Texture2D(GraphicsDevice,
256, 256, 1,
TextureUsage.None,
SurfaceFormat.Color);
//fill the texture
FillFurTexture(furTexture, density);
furColorTexture = Content.Load("bigtiger");
}
///
/// UnloadContent will be called once per game and is the place to unload
/// all content.
///
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}
///
/// Allows the game to run logic such as updating the world,
/// checking for collisions, gathering input, and playing audio.
///
/// Provides a snapshot of timing values.
protected override void Update(GameTime gameTime)
{
// Allows the game to exit
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
// TODO: Add your update logic here
base.Update(gameTime);
}
///
/// This is called when the game should draw itself.
///
/// Provides a snapshot of timing values.
protected override void Draw(GameTime gameTime)
{
forceDirection.X = (float)Math.Sin(gameTime.TotalGameTime.TotalSeconds) * 0.5f;
displacement = gravity + forceDirection;
furEffect.Parameters["Displacement"].SetValue(displacement);
graphics.GraphicsDevice.Clear(Color.CornflowerBlue);
furEffect.Parameters["World"].SetValue(Matrix.CreateTranslation(0, -10, 0));
furEffect.Parameters["View"].SetValue(camera.View);
furEffect.Parameters["Projection"].SetValue(camera.Projection);
furEffect.Parameters["MaxHairLength"].SetValue(maxHairLength);
furEffect.Parameters["FurTexture"].SetValue(furTexture);
furEffect.Parameters["Texture"].SetValue(furColorTexture);
furEffect.Begin();
for (int i = 0; i
/// This functions prepares a texture to be used for fur rendering
///
/// This will contain the final texture
/// Hair density in [0..1] range
private void FillFurTexture(Texture2D furTexture, float density)
{
//read the width and height of the texture
int width = furTexture.Width;
int height = furTexture.Height;
int totalPixels = width * height;
//an array to hold our pixels
Color[] colors;
colors = new Color[totalPixels];
//random number generator
Random rand = new Random();
//initialize all pixels to transparent black
for (int i = 0; i (colors);
}
VertexPositionNormalTexture[] vertices;
private void GenerateGeometry()
{
vertices = new VertexPositionNormalTexture[6];
vertices[0] = new VertexPositionNormalTexture(
new Vector3(-10, 0, 0),
-Vector3.UnitZ,
new Vector2(0, 0));
vertices[1] = new VertexPositionNormalTexture(
new Vector3(10, 20, 0),
-Vector3.UnitZ,
new Vector2(1, 1));
vertices[2] = new VertexPositionNormalTexture(
new Vector3(-10, 20, 0),
-Vector3.UnitZ,
new Vector2(0, 1));
vertices[3] = vertices[0];
vertices[4] = new VertexPositionNormalTexture(
new Vector3(10, 0, 0),
-Vector3.UnitZ,
new Vector2(1, 0));
vertices[5] = vertices[1];
}
private void DrawGeometry()
{
using (VertexDeclaration vdecl = new VertexDeclaration(
GraphicsDevice,
VertexPositionNormalTexture.VertexElements))
{
GraphicsDevice.VertexDeclaration = vdecl;
GraphicsDevice.DrawUserPrimitives(PrimitiveType.TriangleList, vertices, 0, 2);
}
}
}
我小心地将着色器和控制脚本逐行移植到Unity.
Ported Unity着色器:
Shader "Programmer/Fur Shader"
{
Properties
{
_MainTex("Texture", 2D) = "white" {}
//_TintColor("Tint Color", Color) = (1,1,1,1)
}
SubShader
{
Tags{ "Queue" = "Transparent" "RenderType" = "Transparent" }
LOD 100
Blend SrcAlpha One
Blend DstAlpha OneMinusSrcAlpha
ZWrite Off
Cull Off
Pass
{
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
// make fog work
//#pragma multi_compile_fog
#include "UnityCG.cginc"
//In
struct appdata
{
float4 vertex : POSITION;
float2 uv : TEXCOORD0;
};
//Out
struct v2f
{
float2 uv : TEXCOORD0;
UNITY_FOG_COORDS(1)
float4 vertex : SV_POSITION;
};
struct VertexShaderInput
{
float3 Position : POSITION0;
float3 Normal : NORMAL0;
float2 TexCoord : TEXCOORD0;
};
struct VertexShaderOutput
{
float4 Position : POSITION0;
float2 TexCoord : TEXCOORD0;
};
sampler2D _MainTex;
float4 _MainTex_ST;
//Test variable/delete after
float4 _TintColor;
//The variables
float4x4 World;
float4x4 View;
float4x4 Projection;
float CurrentLayer; //value between 0 and 1
float MaxHairLength; //maximum hair length
VertexShaderOutput vert(VertexShaderInput input)
{
VertexShaderOutput output;
float3 pos;
pos = input.Position + input.Normal * MaxHairLength * CurrentLayer;
float4 worldPosition = mul(float4(pos, 1), World);
float4 viewPosition = mul(worldPosition, View);
output.Position = mul(viewPosition, Projection);
output.TexCoord = input.TexCoord;
return output;
}
float4 frag(VertexShaderOutput i) : COLOR0
{
return tex2D(_MainTex, i.TexCoord);
}
ENDCG
}
}
}
用于控制着色器的移植Unity C#脚本:
public class Game1 : MonoBehaviour
{
public Material material;
public Vector3 pos = new Vector3(0f, 0.98f, -9.54f);
//simple camera for use in the game
private new Camera camera;
//texture containing fur data
public Texture2D furTexture;
//effect for fur shaders
//Effect furEffect;
//number of layers of fur
public int nrOfLayers = 40;
//total length of the hair
public float maxHairLength = 2.0f;
//density of hair
public float density = 0.2f;
//[Space(20)]
//public Vector3 dirWorldVal = new Vector3(0, -10, 0);
void Start()
{
Initialize();
GenerateGeometry();
}
public void Update()
{
Draw();
}
void Initialize()
{
//Initialize the camera
camera = Camera.main;
//create the texture
furTexture = new Texture2D(256, 256, TextureFormat.ARGB32, false);
furTexture.wrapModeU = TextureWrapMode.Repeat;
furTexture.wrapModeV = TextureWrapMode.Repeat;
furTexture.filterMode = FilterMode.Point;
//fill the texture
FillFurTexture(furTexture, density);
/*XNA's SurfaceFormat.Color is ARGB.
//https://gamedev.stackexchange.com/a/6442/98839*/
if (material.mainTexture != null)
{
material.mainTexture.wrapModeU = TextureWrapMode.Repeat;
material.mainTexture.wrapModeV = TextureWrapMode.Repeat;
material.mainTexture.filterMode = FilterMode.Point;
}
}
bool firstDraw = true;
protected void Draw()
{
camera.backgroundColor = CornflowerBlue();
Matrix4x4 worldValue = Matrix4x4.Translate(pos);
Matrix4x4 viewValue = camera.projectionMatrix;
// viewValue = camera.worldToCameraMatrix;
Matrix4x4 projectiOnValue= camera.projectionMatrix;
material.SetMatrix("World", worldValue);
material.SetMatrix("View", viewValue);
material.SetMatrix("Projection", projectionValue); //Causes object to disappear
material.SetFloat("MaxHairLength", maxHairLength);
if (firstDraw)
material.SetTexture("_MainTex", furTexture);
//furEffect.Begin();
for (int i = 0; i
Unity的移植VertexPositionNormalTexture结构
public struct VertexPositionNormalTexture
{
public Vector3 Position;
public Vector3 Normal;
public Vector2 TextureCoordinate;
//public static readonly VertexDeclaration VertexDeclaration;
public VertexPositionNormalTexture(Vector3 position, Vector3 normal, Vector2 textureCoordinate)
{
this.Position = position;
this.Normal = normal;
this.TextureCoordinate = textureCoordinate;
}
public override int GetHashCode()
{
// TODO: FIc gethashcode
return 0;
}
public override string ToString()
{
return string.Format("{{Position:{0} Normal:{1} TextureCoordinate:{2}}}", new object[] { this.Position, this.Normal, this.TextureCoordinate });
}
public static bool operator ==(VertexPositionNormalTexture left, VertexPositionNormalTexture right)
{
return (((left.Position == right.Position) && (left.Normal == right.Normal)) && (left.TextureCoordinate == right.TextureCoordinate));
}
public static bool operator !=(VertexPositionNormalTexture left, VertexPositionNormalTexture right)
{
return !(left == right);
}
public override bool Equals(object obj)
{
if (obj == null)
{
return false;
}
if (obj.GetType() != base.GetType())
{
return false;
}
return (this == ((VertexPositionNormalTexture)obj));
}
}
移植的Unity工作无法正常工作.没有炮弹和输出图像是平的.
这是XNA中的预期结果(工作正常):
但这是我在Unity中看到的(没有炮弹):
最终的图像应该看起来像下面的图像,但我不能继续进行移植工作,因为基本实现在Unity中无法正常工作.
我的脚本公共变量设置:
为什么移植的Unity结果是平的？我错过了什么吗？
编辑:
Leo提到了可能的背面问题,因为Unity使用左手坐标系,而XNA使用右手坐标系.
我翻转了UnitZ()值并尝试反转网格顶点,但屏幕上没有任何内容.这不太可能是问题.
1> Leo Bartkus..：
Unity正在对材料进行批量优化.您可以在帧调试器中看到这一点.每个DrawGeometry调用对CurrentLayer使用相同的值.每次调用DrawMesh时都需要使用propertyblock.设置新材料会导致一些闪烁.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
namespace foo {
public class FurBehavior : MonoBehaviour
{
public Material material;
public Vector3 pos = new Vector3(0f, 0.98f, -9.54f);
//simple camera for use in the game
private new Camera camera;
//texture containing fur data
public Texture2D furTexture;
//effect for fur shaders
//Effect furEffect;
//number of layers of fur
public int nrOfLayers = 40;
//total length of the hair
public float maxHairLength = 2.0f;
//density of hair
public float density = 0.2f;
//[Space(20)]
//public Vector3 dirWorldVal = new Vector3(0, -10, 0);
void Start()
{
this.transform.position = new Vector3(0f, 0.98f, -9.54f);
this.transform.rotation = Quaternion.Euler(0, 180, 0);
Initialize();
GenerateGeometry();
}
public void Update()
{
Draw();
}
void Initialize()
{
//Initialize the camera
camera = Camera.main;
//create the texture
furTexture = new Texture2D(256, 256, TextureFormat.ARGB32, false);
furTexture.wrapModeU = TextureWrapMode.Repeat;
furTexture.wrapModeV = TextureWrapMode.Repeat;
//furTexture.filterMode = FilterMode.Point;
//fill the texture
FillFurTexture(furTexture, density);
/*XNA's SurfaceFormat.Color is ARGB.
//https://gamedev.stackexchange.com/a/6442/98839*/
if (material.mainTexture != null)
{
material.mainTexture.wrapModeU = TextureWrapMode.Repeat;
material.mainTexture.wrapModeV = TextureWrapMode.Repeat;
// material.mainTexture.filterMode = FilterMode.Point;
}
}
bool firstDraw = true;
protected void Draw()
{
var pos = this.transform.position;
camera.backgroundColor = CornflowerBlue();
Matrix4x4 worldValue = Matrix4x4.Translate(pos);
Matrix4x4 viewValue = camera.projectionMatrix;
// viewValue = camera.worldToCameraMatrix;
Matrix4x4 projectiOnValue= camera.projectionMatrix;
material.SetMatrix("World", worldValue);
material.SetMatrix("View", viewValue);
material.SetMatrix("Projection", projectionValue); //Causes object to disappear
material.SetFloat("MaxHairLength", maxHairLength);
//if (firstDraw)
material.SetTexture("_MainTex", furTexture);
//furEffect.Begin();
for (int i = 0; i
我还修改了着色器以显示shell.
// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with
'UnityObjectToClipPos(*)'
Shader "Programmer/Fur Shader"
{
Properties
{
_MainTex("Texture", 2D) = "white" {}
_TintColor("Tint Color", Color) = (1,1,1,1)
}
SubShader
{
Tags{ "Queue" = "Transparent" "RenderType" = "Transparent" }
LOD 100
//Blend SrcAlpha One
//Blend DstAlpha OneMinusSrcAlpha
Blend SrcAlpha OneMinusSrcAlpha
ZWrite Off
Cull Off
Pass
{
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
// make fog work
//#pragma multi_compile_fog
#include "UnityCG.cginc"
//In
struct appdata
{
float4 vertex : POSITION;
float2 uv : TEXCOORD0;
};
//Out
struct v2f
{
float2 uv : TEXCOORD0;
UNITY_FOG_COORDS(1)
float4 vertex : SV_POSITION;
};
struct VertexShaderInput
{
float3 Position : POSITION0;
float3 Normal : NORMAL0;
float2 TexCoord : TEXCOORD0;
};
struct VertexShaderOutput
{
float4 Position : POSITION0;
float2 TexCoord : TEXCOORD0;
float4 Tint: COLOR1;
};
sampler2D _MainTex;
float4 _MainTex_ST;
//Test variable/delete after
float4 _TintColor;
//The variables
float4x4 World;
float4x4 View;
float4x4 Projection;
float CurrentLayer; //value between 0 and 1
float MaxHairLength; //maximum hair length
VertexShaderOutput vert(VertexShaderInput input)
{
VertexShaderOutput output;
float3 pos;
pos = input.Position + input.Normal * MaxHairLength * CurrentLayer;
//float4 worldPosition = mul(float4(pos, 1), World);
//float4 viewPosition = mul(worldPosition, View);
output.Position = UnityObjectToClipPos(pos);
output.TexCoord = input.TexCoord;
output.Tint = float4(CurrentLayer, CurrentLayer, 0, 1);
return output;
}
float4 frag(VertexShaderOutput i) : COLOR0
{
float4 t = tex2D(_MainTex, i.TexCoord) * i.Tint;
return t;//float4(t, i.x, i.y, 1);
}
ENDCG
}
}
}
这是在弄乱参数并稍微移动相机后的样子.
京公网安备 11010802041100号