This chapter is a guide map

One 、 Implementation vertex / Chip shader

（ One ） A simple vertex / Chip shader

• 1. Create a new geometry ： stay GameObject Create a new sphere
• 2. Create a new one Unity Shader
• 3. Create a new material , hold Shader Give it to him
• 4. Then assign the material to the corresponding sphere

（ Two ） edit Unity Shader

1. Examples are as follows ：

give the result as follows ：

• first line ：Shader Name
• SubShader Semantic chunk ： Due to the use of default rendering settings and label settings , So you don't need to set .
• Pass Semantic chunk ： The default render settings and label settings are also used
• And then there's the CGPROGRAM and ENDCG Surrounded by CG code snippet
• Compile instructions # pragram vertex/fragment name Represents the vertex shader / The function name of the fragment shader
• Function part ：: The following represents the semantics of variables . for example ：POSITION Indicates that the input is the location of model space ,SV——POSITION Indicates that the output of the vertex shader is the position of the clipping space .
• SV_Target： Represents output to a rendered object , The default here is frame cache
• UNIty_MATRIX_MVP: Pass the coordinates of model space through MVP Change to crop space .

2. Use a structure to define the input of the vertex shader

• Structure member format ： Type（ data type ） Name : Semantic （ The semantics of data ）
• For vertex shader output ,unity Supported semantics by ：POSITION,TANGENT,NORMAL,TEXCOORD0,TEXCOORD1,TEXCOORD2,TEXCOORD3,COLOR etc.
• Be careful , Semantics cannot be omitted , Otherwise, the shader will be confused

3. Communication between vertex shader and slice shader

• Example ：
  
• Be careful ： Vertex shaders are called per vertex , The slice shader is called on a slice by slice basis . The input of the slice shader is actually the result of interpolating the output of the vertex shader .

4. Shader properties

• effect ： Provide convenient parameters for material adjustment
• Location ：Properties In the semantic block
• Example ： among ,'_Color’ For an attribute , The type is Color, The initial value is （1.0,1.0,1.0,1.0）
• in addition , In order to be in CG This attribute can be accessed in the module , Need to be in CG A code block is defined with Properti Variables matching attributes in semantic blocks
  

5. semantics

• Definition ： Semantics is given to Shader Input and output strings , Indicates the meaning of this parameter

• Stage 1 ： When transferring model data to vertex shaders from the application phase Unity Common semantics supported
  

• Stage two ： When passing data from vertex shader to slice shader Unity Common semantics used
  

• Stage three ： Chip shader output Unity Common semantics supported
  

• Example