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with
Datatypes,
ANSI_Terminal,
Ada.Characters.Latin_1,
Ada.Text_IO;
use
Datatypes;
use type
Datatypes.Plane.Complex;
procedure Fluid_Simulator is
package ANSI renames ANSI_Terminal;
package Latin renames Ada.Characters.Latin_1;
package IO renames Ada.Text_IO;
Particles : Particle_Vector := Particle_Vectors.Empty_Vector;
-- Constant properties of particles
Particle_Radius : constant Quantity := 2.0;
Particle_Mass : constant Quantity := 1.0;
-- Constant used in calculating fluid interaction forces
P0 : constant Quantity := 1.5;
-- Other constant force factors
Gravity_Factor : constant Plane.Complex := Plane.Compose_From_Cartesian (0.0, 1.0);
Pressure_Factor : constant Quantity := 4.0;
Viscosity_Factor : constant Quantity := 8.0;
procedure Read_Input
(Store : out Particle_Vector)
is
Input : Character;
X, Y : Quantity := 1.0;
begin
while not IO.End_Of_File (IO.Standard_Input) loop
IO.Get_Immediate (Input);
if Input = Latin.LF then
X := 1.0;
Y := Y + 2.0;
else
if Input > Latin.Space and Input < Latin.DEL then
Store.Append (Create (X, Y, (Input = '#')));
Store.Append (Create (X, Y + 1.0, (Input = '#')));
end if;
X := X + 1.0;
end if;
end loop;
end Read_Input;
procedure Calculate_Density
(Store : in out Particle_Vector)
is
Rij, W : Quantity;
begin
for P of Store loop
P.Density := (if P.Solid then 9.0 else 0.0);
for Q of Store loop
Rij := Plane.Modulus (P.Place - Q.Place);
W := (Rij / Particle_Radius - 1.0) ** 2;
if Rij < Particle_Radius then
P.Density := P.Density + Particle_Mass * W;
end if;
end loop;
end loop;
end Calculate_Density;
procedure Calculate_Interaction
(Store : in out Particle_Vector)
is
Displacement, Pressure, Viscosity : Plane.Complex;
Rij : Quantity;
begin
for P of Store loop
if not P.Solid then
P.Acceleration := Gravity_Factor;
for Q of Store loop
Displacement := P.Place - Q.Place;
Rij := Plane.Modulus (Displacement);
if Rij < Particle_Radius then
Pressure := (P.Density + Q.Density - 2.0 * P0) *
Pressure_Factor * Displacement;
Viscosity := (P.Velocity - Q.Velocity) * Viscosity_Factor;
P.Acceleration := P.Acceleration +
Plane.Compose_From_Cartesian (1.0 - Rij / Particle_Radius) /
P.Density * (Pressure - Viscosity);
end if;
end loop;
end if;
end loop;
end Calculate_Interaction;
procedure Update_Position
(Store : in out Particle_Vector) is
begin
for P of Store loop
if not P.Solid then
P.Velocity := P.Velocity + P.Acceleration / 10.0;
P.Place := P.Place + P.Velocity;
end if;
end loop;
end Update_Position;
procedure Cull_Outside_Bounds
(Store : in out Particle_Vector;
Threshold : in Quantity) is
begin
for C in reverse Store.First_Index .. Store.Last_Index loop
if Plane.Re (Store (C).Place) < 1.0 - Threshold or
Plane.Re (Store (C).Place) > 80.0 + Threshold or
Plane.Im (Store (C).Place) < 1.0 - Threshold or
Plane.Im (Store (C).Place) > 50.0 + Threshold
then
Store.Delete (C);
end if;
end loop;
end Cull_Outside_Bounds;
begin
Read_Input (Particles);
loop
Calculate_Density (Particles);
ANSI.Clear_Screen;
ANSI.Reset_Cursor;
IO.Put (ANSI.Marching_Squares (Particles));
Calculate_Interaction (Particles);
Update_Position (Particles);
Cull_Outside_Bounds (Particles, 50.0);
delay 0.012321;
end loop;
end Fluid_Simulator;
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