color only shader

float 4x4 view_proj_matrix;float4 vs_main( float4 inPos:POSITION ){     return mul( inPos , view_proj_matrix );}float4 ps_main( float4 inDiffuse : COLOR0 ) : COLOR0{     float4 color = float4(0,0,0,0);     color.r = 1.0;     color.a = 1.0;     return color;}