compile to VULKAN

After added "#define of SHADER_API_VULKAN" can't compile unity shader../
someone know why?


#define SHADER_API_VULKAN
//#define SHADER_API_GLCORE
//#define UNITY_COMPILER_HLSLCC
/*#undef SHADER_API_MOBILE
#undef SHADER_API_METAL
#undef SHADER_API_VULKAN
#undef SHADER_API_GLES3*/
#define SHADER_TARGET 50
#define UNITY_PBS_USE_BRDF1
//#pragma target 5.0
//#define UNITY_PBS_USE_BRDF3
//#define SHADER_API_GLCORE
/*#define fixed float
#define fixed2 float2
#define fixed3 float3
#define fixed4 float4
#define fixed4x4 float4x4
#define fixed3x3 float3x3
#define fixed2x2 float2x2
#define half float
#define half2 float2
#define half3 float3
#define half4 float4
#define half2x2 float2x2
#define half3x3 float3x3
#define half4x4 float4x4
*/
// michael's fix
/*#define half min16float
#define half2 min16float2
#define half3 min16float3
#define half4 min16float4
#define half2x2 min16float2x2
#define half3x3 min16float3x3
#define half4x4 min16float4x4
*/
#include "Header.hlsli"
/*half main() : SV_TARGET
{
half4 zhopa = half4(0.0f, 0.0f, 1.0f, 1.0f);
half res = ShadeSH9(zhopa);
return res;
//return float4(1.0f, 1.0f, 1.0f, 1.0f);
}*/
struct ps_in {
half4 text0: TEXCOORD0;
half4 text1: TEXCOORD1;
half4 text2: TEXCOORD2;
half4 text3: TEXCOORD3;
};
/*
min16float4 BRDF1_Unity_PBS(min16float3 diffColor, min16float3 specColor, min16float oneMinusReflectivity, min16float smoothness,
float3 normal, float3 viewDir,
UnityLight light, UnityIndirect gi)
*/
cbuffer zhopa
{
UnityLight light;
UnityIndirect gi;
};
half4 main(ps_in In) : SV_TARGET
{
//half4 zhopa = half4(0.0f, 0.0f, 1.0f, 1.0f);
//half4 res = BRDF1_Unity_PBS(In.text0.rgb, In.text1.rgb, In.text0.a, In.text1.a, In.text2.rgb, In.text3.rgb, light, gi);
half4 res = UNITY_BRDF_PBS(In.text0.rgb, In.text1.rgb, In.text0.a, In.text1.a, In.text2.rgb, In.text3.rgb, light, gi);
return res;
//return float4(1.0f, 1.0f, 1.0f, 1.0f);
}

 

1>C:\Users\user\Downloads\unityShader\CGIncludes\UnityShaderVariables.cginc(119,11-28): error X3650: 'unity_4LightAtten0': global variables cannot use the 'half' type in ps_5_0. To treat this variable as a float, use the backwards compatibility flag.