Refactored code into appropriate packages

5 files changed, 246 insertions, 167 deletions

diff --git a/src/ansi_terminal.adb b/src/ansi_terminal.adb
new file mode 100644
index 0000000..c356c21
--- /dev/null
+++ b/src/ansi_terminal.adb
@@ -0,0 +1,123 @@
+
+with
+
+    Ada.Characters.Latin_1,
+    Ada.Strings.Fixed,
+    Ada.Text_IO;
+
+package body ANSI_Terminal is
+
+    package Latin renames Ada.Characters.Latin_1;
+    package IO renames Ada.Text_IO;
+
+
+
+    function Clear_Screen
+        return String is
+    begin
+        --  ANSI control sequence Erase in Display
+        --  Variant to clear entire screen
+        return Latin.ESC & "[2J";
+    end Clear_Screen;
+
+    function Reset_Cursor
+        return String is
+    begin
+        --  ANSI control sequence Cursor Position
+        --  Parameters to move cursor to top left corner
+        return Latin.ESC & "[1;1H";
+    end Reset_Cursor;
+
+    procedure Clear_Screen is
+    begin
+        IO.Put (Clear_Screen);
+    end Clear_Screen;
+
+    procedure Reset_Cursor is
+    begin
+        IO.Put (Reset_Cursor);
+    end Reset_Cursor;
+
+
+
+    function BG_Color_Code
+           (Value : in Natural)
+        return String
+    is
+        use Ada.Strings;
+        use Ada.Strings.Fixed;
+    begin
+        --  ANSI sequence to change text background colour
+        --  Total length is always 11 characters
+        --  It doesn't have to be, but the consistency is important for rendering
+        return Latin.ESC & "[48;5;" & Tail (Trim (Integer'Image (Value), Left), 3, '0') & "m";
+    end BG_Color_Code;
+
+
+
+    function Lookup
+           (Input : in March_Cell_Grid;
+            X, Y  : in Integer)
+        return String
+    is
+        Average_Density : Natural := Integer (Quantity'Ceiling (Input (X, Y).Density / 4.0));
+        Bit_Index : Positive := Integer (Input (X, Y).Index) + 1;
+        Choice : Natural;
+    begin
+        case Average_Density is
+            when  1 ..  2 => Choice := 19; --  dark blue
+            when  3 ..  4 => Choice := 20; --  slightly less dark blue
+            when  5 ..  6 => Choice := 21; --  slightly dark blue
+            when  7 ..  8 => Choice := 12; --  blue
+            when  9 .. 10 => Choice := 14; --  cyan
+            when 11 .. 12 => Choice := 10; --  green
+            when 13 .. 14 => Choice := 11; --  yellow
+            when 15 .. 16 => Choice :=  3; --  dark yellow
+            when 17 .. 18 => Choice :=  9; --  red
+            when 19 .. 20 => Choice :=  1; --  dark red
+            when others   => Choice :=  0; --  black
+        end case;
+        --  Total length should always be 12 characters
+        return BG_Color_Code (Choice) & Liquid_Chars (Bit_Index);
+    end Lookup;
+
+    function Marching_Squares
+           (Input : in Particle_Vector)
+        return String
+    is
+        --  Having the grid be one bigger around the edges simplifies calculations
+        Grid : March_Cell_Grid (0 .. 81, 0 .. 26);
+
+        --  80 cols * 25 rows * 12 chars/cell + 24 linefeeds + 4 char color reset = 24028
+        --  Oh yeah, baby, big strings
+        Output : String (1 .. 24028);
+
+        X, Y, S : Integer;
+    begin
+        for P of Input loop
+            X := Integer (Plane.Re (P.Place) - 0.5);
+            Y := Integer (Plane.Im (P.Place) / 2.0 - 0.5);
+            if X >= 0 and X <= 80 and Y >= 0 and Y <= 25 then
+                for J in Integer range 0 .. 1 loop
+                    for I in Integer range 0 .. 1 loop
+                        Grid (X + I, Y + J).Index :=
+                            Grid (X + I, Y + J).Index or (2 ** (I + 2 * J));
+                        Grid (X + I, Y + J).Density :=
+                            Grid (X + I, Y + J).Density + P.Density;
+                    end loop;
+                end loop;
+            end if;
+        end loop;
+        for J in Integer range 1 .. 25 loop
+            for I in Integer range 1 .. 80 loop
+                S := (J - 1) * 961 + (I - 1) * 12 + 1;
+                Output (S .. S + 11) := Lookup (Grid, I, J);
+            end loop;
+            Output (J * 961) := Latin.LF;
+        end loop;
+        Output (24025 .. 24028) := Latin.ESC & "[0m";
+        return Output;
+    end Marching_Squares;
+
+end ANSI_Terminal;
+
diff --git a/src/ansi_terminal.ads b/src/ansi_terminal.ads
new file mode 100644
index 0000000..027f771
--- /dev/null
+++ b/src/ansi_terminal.ads
@@ -0,0 +1,41 @@
+
+with
+
+    Datatypes;
+
+package ANSI_Terminal is
+
+    function Clear_Screen
+        return String;
+
+    function Reset_Cursor
+        return String;
+
+    procedure Clear_Screen;
+    procedure Reset_Cursor;
+
+    function BG_Color_Code
+           (Value : in Natural)
+        return String;
+
+    function Marching_Squares
+           (Input : in Datatypes.Particle_Vector)
+        return String;
+
+private
+
+    use Datatypes;
+
+    Liquid_Chars : constant String (1 .. 16) := " ,.-`[//'\]\-\/#";
+
+    type Liquidex is mod 2**4;
+
+    type March_Cell is record
+        Index   : Liquidex := 0;
+        Density : Quantity := 0.0;
+    end record;
+
+    type March_Cell_Grid is array (Integer range <>, Integer range <>) of March_Cell;
+
+end ANSI_Terminal;
+
diff --git a/src/datatypes.adb b/src/datatypes.adb
new file mode 100644
index 0000000..64ff017
--- /dev/null
+++ b/src/datatypes.adb
@@ -0,0 +1,15 @@
+
+package body Datatypes is
+
+
+    function Create
+           (X, Y  : Quantity;
+            Solid : in Boolean)
+        return Particle is
+    begin
+        return (Place => Plane.Compose_From_Cartesian (X, Y), Solid => Solid, others => <>);
+    end Create;
+
+
+end Datatypes;
+
diff --git a/src/datatypes.ads b/src/datatypes.ads
new file mode 100644
index 0000000..50d21f9
--- /dev/null
+++ b/src/datatypes.ads
@@ -0,0 +1,33 @@
+
+with
+
+    Ada.Numerics.Generic_Complex_Types,
+    Ada.Containers.Vectors;
+
+package Datatypes is
+
+    type Quantity is digits 18;
+
+    package Plane is new Ada.Numerics.Generic_Complex_Types (Real => Quantity);
+
+    type Particle is record
+        Place        : Plane.Complex;
+        Solid        : Boolean;
+        Density      : Quantity := 0.0;
+        Acceleration : Plane.Complex := Plane.Compose_From_Cartesian (0.0, 0.0);
+        Velocity     : Plane.Complex := Plane.Compose_From_Cartesian (0.0, 0.0);
+    end record;
+
+    function Create
+           (X, Y  : in Quantity;
+            Solid : in Boolean)
+        return Particle;
+
+    package Particle_Vectors is new Ada.Containers.Vectors
+       (Index_Type   => Positive,
+        Element_Type => Particle);
+
+    subtype Particle_Vector is Particle_Vectors.Vector;
+
+end Datatypes;
+
diff --git a/src/fluid_simulator.adb b/src/fluid_simulator.adb
index b8d47ce..f683259 100644
--- a/src/fluid_simulator.adb
+++ b/src/fluid_simulator.adb
@@ -1,57 +1,29 @@
 
 with
 
-    Ada.Numerics.Generic_Complex_Types,
-    Ada.Containers.Vectors,
+    Datatypes,
+    ANSI_Terminal,
     Ada.Characters.Latin_1,
-    Ada.Strings.Fixed,
     Ada.Text_IO;
 
-procedure Fluid_Simulator is
-
-    package Latin renames Ada.Characters.Latin_1;
-    package IO renames Ada.Text_IO;
+use
 
+    Datatypes;
 
+use type
 
-    procedure Clear_Screen is
-    begin
-        --  ANSI control sequence Erase in Display
-        --  Variant to clear entire screen
-        IO.Put (Latin.ESC & "[2J");
-    end Clear_Screen;
-
-    procedure Reset_Cursor is
-    begin
-        --  ANSI control sequence Cursor Position
-        --  Parameters to move cursor to top left corner
-        IO.Put (Latin.ESC & "[1;1H");
-    end Reset_Cursor;
+    Datatypes.Plane.Complex,
+    Datatypes.Plane.Imaginary;
 
+procedure Fluid_Simulator is
 
+    package ANSI renames ANSI_Terminal;
+    package Latin renames Ada.Characters.Latin_1;
+    package IO renames Ada.Text_IO;
 
-    type Quantity is digits 18;
-
-    package Fixed is new Ada.Numerics.Generic_Complex_Types (Real => Quantity);
-    use type Fixed.Complex;
-
-    type Particle is record
-        Place        : Fixed.Complex;
-        Solid        : Boolean;
-        Density      : Quantity := 0.0;
-        Acceleration : Fixed.Complex := Fixed.Compose_From_Cartesian (0.0, 0.0);
-        Velocity     : Fixed.Complex := Fixed.Compose_From_Cartesian (0.0, 0.0);
-    end record;
-
-    function Create
-           (X, Y  : Quantity;
-            Solid : in Boolean)
-        return Particle is
-    begin
-        return (Place => Fixed.Compose_From_Cartesian (X, Y), Solid => Solid, others => <>);
-    end Create;
 
 
+    Particles : Particle_Vector := Particle_Vectors.Empty_Vector;
 
     --  Constant properties of particles
     Particle_Radius : constant Quantity := 2.0;
@@ -61,22 +33,14 @@ procedure Fluid_Simulator is
     P0 : constant Quantity := 1.5;
 
     --  Other constant force factors
-    Gravity_Factor : constant Fixed.Complex := Fixed.Compose_From_Cartesian (0.0, 1.0);
-    Pressure_Factor : constant Quantity := 4.0;
+    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;
 
 
 
-    package Particle_Vectors is new Ada.Containers.Vectors
-       (Index_Type   => Positive,
-        Element_Type => Particle);
-
-    Particles : Particle_Vectors.Vector := Particle_Vectors.Empty_Vector;
-
-
-
     procedure Read_Input
-           (Store : out Particle_Vectors.Vector)
+           (Store : out Particle_Vector)
     is
         Input : Character;
         X, Y : Quantity := 1.0;
@@ -98,110 +62,15 @@ procedure Fluid_Simulator is
 
 
 
-    --  Liquid_Chars : constant String (1 .. 16) := " .,_`/[/']\\-/\#";
-    Liquid_Chars : constant String (1 .. 16) := " ,.-`[//'\]\-\/#";
-
-    type Liquidex is mod 2**4;
-
-    type March_Cell is record
-        Index : Liquidex := 0;
-        Density : Quantity := 0.0;
-    end record;
-
-    type March_Cell_Grid is array (Integer range <>, Integer range <>) of March_Cell;
-
-
-
-    function BG_Color_Code
-           (Value : in Natural)
-        return String
-    is
-        use Ada.Strings;
-        use Ada.Strings.Fixed;
-    begin
-        --  Total length is always 11 characters
-        return Latin.ESC & "[48;5;" & Tail (Trim (Integer'Image (Value), Left), 3, '0') & "m";
-    end BG_Color_Code;
-
-
-
-    function Lookup
-           (Input : in March_Cell_Grid;
-            X, Y  : in Integer)
-        return String
-    is
-        Average_Density : Natural := Integer (Quantity'Ceiling (Input (X, Y).Density / 4.0));
-        Bit_Index : Positive := Integer (Input (X, Y).Index) + 1;
-        Choice : Natural;
-    begin
-        case Average_Density is
-            when 1 .. 2 => Choice := 19; --  dark blue
-            when 3 .. 4 => Choice := 20; --  slightly less dark blue
-            when 5 .. 6 => Choice := 21; --  slightly dark blue
-            when 7 .. 8 => Choice := 12; --  blue
-            when 9 .. 10 => Choice := 14; --  cyan
-            when 11 .. 12 => Choice := 10; --  green
-            when 13 .. 14 => Choice := 11; --  yellow
-            when 15 .. 16 => Choice := 3; --  dark yellow
-            when 17 .. 18 => Choice := 9; --  red
-            when 19 .. 20 => Choice := 1; --  dark red
-            when others => Choice := 0; --  black
-        end case;
-        --  Total length should always be 12 characters
-        return BG_Color_Code (Choice) & Liquid_Chars (Bit_Index);
-    end Lookup;
-
-
-
-    function Marching_Squares
-           (Input : in Particle_Vectors.Vector)
-        return String
-    is
-        --  Having the grid be one bigger around the edges simplifies calculations
-        Grid : March_Cell_Grid (0 .. 81, 0 .. 26);
-
-        --  80 cols * 25 rows * 12 chars/cell + 24 linefeeds + 4 char color reset = 24028
-        --  Oh yeah, baby, big strings
-        Output : String (1 .. 24028);
-
-        X, Y, S : Integer;
-    begin
-        for P of Input loop
-            X := Integer (Fixed.Re (P.Place) - 0.5);
-            Y := Integer (Fixed.Im (P.Place) / 2.0 - 0.5);
-            if X >= 0 and X <= 80 and Y >= 0 and Y <= 25 then
-                for J in Integer range 0 .. 1 loop
-                    for I in Integer range 0 .. 1 loop
-                        Grid (X + I, Y + J).Index :=
-                            Grid (X + I, Y + J).Index or (2 ** (I + 2 * J));
-                        Grid (X + I, Y + J).Density :=
-                            Grid (X + I, Y + J).Density + P.Density;
-                    end loop;
-                end loop;
-            end if;
-        end loop;
-        for J in Integer range 1 .. 25 loop
-            for I in Integer range 1 .. 80 loop
-                S := (J - 1) * 961 + (I - 1) * 12 + 1;
-                Output (S .. S + 11) := Lookup (Grid, I, J);
-            end loop;
-            Output (J * 961) := Latin.LF;
-        end loop;
-        Output (24025 .. 24028) := Latin.ESC & "[0m";
-        return Output;
-    end Marching_Squares;
-
-
-
     procedure Calculate_Density
-           (Store : in out Particle_Vectors.Vector)
+           (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 := Fixed.Modulus (P.Place - Q.Place);
+                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;
@@ -210,34 +79,31 @@ procedure Fluid_Simulator is
         end loop;
     end Calculate_Density;
 
-
-
     procedure Calculate_Interaction
-           (Store : in out Particle_Vectors.Vector)
+           (Store : in out Particle_Vector)
     is
-        Displacement, Pressure, Viscosity : Fixed.Complex;
+        Displacement, Pressure, Viscosity : Plane.Complex;
         Rij : Quantity;
     begin
         for P of Store loop
             P.Acceleration := Gravity_Factor;
             for Q of Store loop
                 Displacement := P.Place - Q.Place;
-                Rij := Fixed.Modulus (Displacement);
+                Rij := Plane.Modulus (Displacement);
                 if Rij < Particle_Radius then
-                    Pressure := (P.Density + Q.Density - 2.0 * P0) * Pressure_Factor * Displacement;
+                    Pressure := (P.Density + Q.Density - 2.0 * P0) *
+                        Pressure_Factor * Displacement;
                     Viscosity := (P.Velocity - Q.Velocity) * Viscosity_Factor;
                     P.Acceleration := P.Acceleration +
-                        Fixed.Compose_From_Cartesian (1.0 - Rij / Particle_Radius) /
+                        Plane.Compose_From_Cartesian (1.0 - Rij / Particle_Radius) /
                         P.Density * (Pressure - Viscosity);
                 end if;
             end loop;
         end loop;
     end Calculate_Interaction;
 
-
-
     procedure Update_Position
-           (Store : in out Particle_Vectors.Vector) is
+           (Store : in out Particle_Vector) is
     begin
         for P of Store loop
             if not P.Solid then
@@ -250,27 +116,28 @@ procedure Fluid_Simulator is
 
 
     procedure Cull_Outside_Bounds
-           (Store     : in out Particle_Vectors.Vector;
-            Threshold : in Quantity) is
+           (Store     : in out Particle_Vector;
+            Threshold : in     Quantity) is
     begin
         for C in reverse Store.First_Index .. Store.Last_Index loop
-            if Fixed.Re (Store (C).Place) < 1.0 - Threshold or
-               Fixed.Re (Store (C).Place) > 80.0 + Threshold or
-               Fixed.Im (Store (C).Place) < 1.0 - Threshold or
-               Fixed.Im (Store (C).Place) > 50.0 + Threshold
+            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
-        Clear_Screen;
-        Reset_Cursor;
-        IO.Put (Marching_Squares (Particles));
+        ANSI.Clear_Screen;
+        ANSI.Reset_Cursor;
+        IO.Put (ANSI.Marching_Squares (Particles));
         Calculate_Density (Particles);
         Calculate_Interaction (Particles);
         Update_Position (Particles);