关于Unity中Shader的内置值

4.2版本

 

UNITY_MATRIX_MVP

Current model*view*projection matrix
当前模型*视*投影矩阵。（注：模型矩阵为 本地->世界）

UNITY_MATRIX_MV

Current model*view matrix
当前模型*视图矩阵

UNITY_MATRIX_V

Current view matrix.
当前视图矩阵

UNITY_MATRIX_P

Current projection matrix
当前投影矩阵

UNITY_MATRIX_VP

Current view*projection matrix
当前视图*投影矩阵

UNITY_MATRIX_T_MV

Transpose of model*view matrix
转置模型*视图矩阵

UNITY_MATRIX_IT_MV

Inverse transpose of model*view matrix
逆转置模型*视矩阵

UNITY_MATRIX_TEXTURE0 to UNITY_MATRIX_TEXTURE3

Texture transformation matrices
纹理变换矩阵

float4x4 _Object2World

Current model matrix
当前物体矩阵

float4x4 _World2Object

Inverse of current world matrix
物体矩阵的逆矩阵

float3 _WorldSpaceCameraPos

World space position of the camera
世界坐标空间中的摄像机位置

float4 unity_Scale

xyz components unused; .w contains scale for uniformly scaled objects.
不适用xyz分量，而是通过w分量包含的缩放值等比缩放物体。

Lighting 光照

In plain ShaderLab, you access the following properties by appending zero at the end: e.g. the light's model*light color is _ModelLightColor0. In Cg shaders, they are exposed as arrays with a single element, so the same in Cg is _ModelLightColor[0].

在纯粹的ShaderLab中，你可以利用下面这些属性，只要在末尾增加一个零数：例如 灯光的物体*灯光颜色是_ModelLightColor0.在Cgshader中这些变量更像是一个包含单一元素的数组。所以在Cg中他们是这样的_ModelLightColor[0];

Name
Type
Value

_ModelLightColor
float4
Material's Main * Light color 材质的主颜色*灯光颜色

_SpecularLightColor
float4
Material's Specular * Light color 材质的镜面反射（高光）*灯光颜色。

_ObjectSpaceLightPos
float4
Light's position in object space. w component is 0 for directional lights, 1 for other lights
物体空间中的灯光为，平行光w分量为零其灯光为1；

_Light2World
float4x4
Light to World space matrix 灯光转世界空间矩阵

_World2Light
float4x4
World to Light space matrix 世界转灯光空间矩阵

_Object2Light
float4x4
Object to Light space matrix 物体转灯光空间矩阵

Various 变量

• float4 _Time : Time (t/20, t, t*2, t*3), use to animate things inside the shaders
  时间： 用于Shasder中可动画的地方。
• float4 _SinTime : Sine of time: (t/8, t/4, t/2, t)
  时间的正弦值。
• float4 _CosTime : Cosine of time: (t/8, t/4, t/2, t)
  时间的余弦值
• float4 _ProjectionParams : 投影参数
  x is 1.0 or -1.0, negative if currently rendering with a flipped projection matrix
  x为1.0 或者-1.0如果当前渲染使用的是一个反转的投影矩阵那么为负。
  y is camera's near plane y是摄像机的近剪裁平面
  z is camera's far plane z是摄像机远剪裁平面
  w is 1/FarPlane. w是1/远剪裁平面
• float4 _ScreenParams : 屏幕参数
  x is current render target width in pixels x是当前渲染目标在像素值中宽度
  y is current render target height in pixels y是当前渲染目标在像素值中的高度
  z is 1.0 + 1.0/width z是1.0+1.0/宽度
  w is 1.0 + 1.0/height w是1.0+1.0/高度