transformation matrix
| variable name | describe |
| UNITY_MATRIX_MVP | The current model-view-projection matrix used to transform vertex/orientation vectors from model space to clip space |
| UNITY_MATRIX_MV | The current model-view matrix used to transform the vertex/orientation vectors from model space to view space |
| UNITY_MATRIX_V | Current view matrix, used to transform vertex/orientation vectors from world space to view space |
| UNITY_MATRIX_P | The current projection matrix used to transform the vertex/orientation vectors from view space to clip space |
| UNITY_MATRIX_VP | The current view-projection matrix used to transform vertex/orientation vectors from world space to clip space |
| UNITY_MATRIX_T_MV | Transpose matrix of UNITY_MATRIX_T_MV |
| UNITY_MATRIX_IT_MV | The inverse transposition matrix of UNITY_MATRIX_T_MV, used to transform the normal from the model space to the observation space, can also be used to get the inverse matrix of UNITY_MATRIX_T_MV |
| _Object2World | The current magic heart matrix used to transform the vertex/orientation vector from model space to world space |
| _World2Object | The inverse matrix of _Object2World, used to transform the fixed point/orientation vector from world space to model space |
Camera and Screen Parameters
| variable name | type | describe |
| _WorldSpaceCameraPos | float3 | The position of this camera in world space |
| _ProjectionParams | float4 | x=1.0 (or -1.0, if you are using an inverted projection matrix for rendering), y=Near, z=Far, w=1.0+1.0/Far, where Near and Far are divided into near clipping plane and far clipping plane distance from camera |
| _ScreenParams | float4 | x=width, y=height, z=1.0+1.0/width, w=1.0+1.0/height, where width and height are the pixel width and height of the rendering target of the camera respectively |
| _ZBufferParams | float4 | x=1-Far/Near, y=Far/Near, z=x/Far, w=y/Far, this variable is used to linearize the depth value in the Z buffer |
| unity_OrthoParams | float4 | x=width, y=height, z is not defined, w=1.0 (the camera is an orthographic camera) or w=0.0 (the camera is a perspective camera), where width and height are the width and height of the orthographic projection camera |
| unity_CameraProjection | float4x4 | The projection matrix for this camera |
| unity_CameraIveProjection | float4x4 | the inverse of the camera's projection matrix |
| unity_CameraWorldClipPlanes[6] | float4 | The lighting of the camera's 6 clipping planes in world space, in the following order: left, right, bottom, top, near, and far clipping planes |
time
| variable name | type | describe |
| _Time | float4 | Time calculated from scene loading (t/20,t,t*2,t*3), used for animation in shader |
| _SinTime | float4 | Sine value of time (t/8,t/4,t/2,t) |
| _CosTime | float4 | Cosine value of time (t/8,t/4,t/2,t) |
| unity_DeltaTime | float4 | Interframe time (dt, 1/dt, smoothDt, 1/smoothDt). |
Lighting variables for forward rendering
| variable name | type | describe |
| _LightColor0(declared in Lighting.cginc) |
fixed4 |
light color |
| _WorldSpaceLightPos0 |
float4 |
The position of the light source in the world space, w=0 represents the direction of the parallel light, and w=1 represents the position of other light sources |
| _LightMatrix0(declared in AutoLight.cginc) |
float4x4 |
Transform vertices from world space to light space |
| unity_4LightPosX0, unity_4LightPosY0, unity_4LightPosZ0 |
float4 |
(ForwardBase channel only) The world space coordinates of the first four unimportant point lights |
| unity_4LightAtten0 |
float4 |
(ForwardBase channel only) Attenuation coefficients for the first four unimportant point lights |
| unity_LightColor |
half4[4] |
(Only ForwardBase passes) The color array of the first four unimportant point light sources, used to calculate the vertex light source |
Delayed lighting related variables
| variable name | type | describe |
| _LightColor |
float4 |
light color |
| _LightMatrix0 |
float4x4 |
把顶点从世界空间变换到光源空间 |
顶点光照相关变量
| 变量名 | 类型 | 描述 |
| unity_LightColor |
half4[8] |
光线颜色 |
| unity_LightPosition |
float4[8] |
视图空间光源的位置。方向光源的坐标是（-方向，0）；（位置，1）用于点/点指示灯，点光源，聚光灯的坐标是（位置，1） |
| unity_LightAtten |
half4[8] |
光源衰减系数。x=cos(spotAngle/2)或非聚光灯为-1；y=1/cos(spotangle/4)或非聚光灯为-1；z是衰减的二次方；w是正方形光源的范围 |
| unity_SpotDirection |
float4[8] |
如果光源是聚光灯的话，值为视图空间的聚光灯的位置，如果是其他类型的光源，值为（0,0,1,0）。 |