基于Claude3.5，写了个2D草摆动的Shader，指令顺序：
1. Write a 2D shader: grass wave
2. translate to Unity Shaderlab
3. from CGPROGRAM to HLSLPROGRAM
4. the grass should wave like be blowed by wind
5. run the code: grass top is pinned. I need pin the grass bottom
（请忽略我蹩脚的英语，毕竟AI都没嫌弃我）
1. Write a 2D shader: grass wave
2. translate to Unity Shaderlab
3. from CGPROGRAM to HLSLPROGRAM
4. the grass should wave like be blowed by wind
5. run the code: grass top is pinned. I need pin the grass bottom
（请忽略我蹩脚的英语，毕竟AI都没嫌弃我）