OpenEuphoria

Re: Phix: cffi.e

• Posted by petelomax 6 days ago
• 332 views

In Phix I'd start with something like this (NB completely untested)

include cffi.e 
constant t_Vector2 = """ 

typedef struct Vector2 {  
    float x;                // Vector x component  
    float y;                // Vector y component  
} Vector2; """ 

constant idVector2 = define_struct(t_Vector2), 
         pVector2 = allocate_struct(idVector2) 
  
-- (you might get away with passing/need to pass #RRGGBBAA values directly, 
--  and/or allocate(4) and poke4(said) might be much neater...) 
constant t_Color = """ 

typedef struct Color { 
    unsigned char r;        // Color red value 
    unsigned char g;        // Color green value 
    unsigned char b;        // Color blue value 
    unsigned char a;        // Color alpha value 
} Color;""" 
constant idColor = define_struct(t_Color), 
         pColor = allocate_struct(idColor) 
 
-- I can tell you this kind of thing simply won't work: 
--constant xDrawCircleV = define_c_proc(ray,"+DrawCircleV",{VECTOR2,C_FLOAT,COLOR})  
-- instead: 
local constant xDrawCircleV = define_c_proc(ray,"+DrawCircleV",{C_PTR,C_FLOAT,C_PTR})  
  
global procedure DrawCircleV(sequence vector2, atom radius, sequence color)  
    atom {x,y} = vector2 
    set_struct_field(idVector2,pVector2,"x",x) 
    set_struct_field(idVector2,pVector2,"y",y) 
    integer {r,g,b,a} = color 
    set_struct_field(idColor,pColor,"r",r) 
    set_struct_field(idColor,pColor,"g",g) 
    set_struct_field(idColor,pColor,"b",b) 
    set_struct_field(idColor,pColor,"a",a) 
    c_proc(xDrawCircleV,{pVector2,radius,pColor})  
end procedure  
 
-- if an alpha of 255 means fully transparent, this won't show anything: 
DrawCircleV({10,10},20,{255,255,255,255})