# Error setting the video mode when trying to run the compiled Game_Support example; GNAT Studio;

Trying to compile example `/opt/gnatstudio/share/examples/training/games/bouncing/bouncing.gpr`

There are no problems when compiling, but when running -

```
Error setting the video mode
UNCAUGHT EXCEPTION ===
raised STORAGE_ERROR : s-intman.adb:136 explicit raise
```

Code sample, which I used (it had been moved to another folder, because it does not want to compile in /opt/ - no rights).

```
with Display; use Display;
with Display.Basic; use Display.Basic;
with Ada.Numerics; use Ada.Numerics;
with Ada.Numerics.Generic_Elementary_Functions;
with Ada.Text_IO; use Ada.Text_IO;
with Ada.Numerics.Float_Random; use Ada.Numerics.Float_Random;
procedure Bouncing is
Seed : Generator;
Buffer_Size : constant := 1_200;
package F_Numeri is new Ada.Numerics.Generic_Elementary_Functions (Float);
use F_Numeri;
Base_Immunity : constant := 500;
type Ball is record
X, Y : Float := 0.0;
Dx, Dy : Float := 0.0;
Size : Float := 0.0;
Mass : Float := 1.0;
S : Shape_Id := Null_Shape_Id;
Immunity : Integer := Base_Immunity;
end record
with Dynamic_Predicate => Ball.Mass > 0.0;
type Shape_Array_Type is array (Integer range <>) of Shape_Id;
type Ball_Array_Type is array (Integer range <>) of Ball;
Null_Ball : constant Ball := Ball'(X => 0.0,
Y => 0.0,
Dx => 0.0,
Dy => 0.0,
Size => 0.0,
Mass => 1.0,
S => Null_Shape_Id,
Immunity => Base_Immunity);
Total_Ball : Integer := 0;
function Speed (B : Ball) return Float is
(Sqrt (B.Dx * B.Dx + B.Dy * B.Dy));
function Cynetic_Energy (B : Ball) return Float is
(1.0 / 2.0 * B.Mass * Speed (B) * Speed (B));
function Speed (Cy : Float; Mass : Float) return Float is
(Sqrt (Cy * 2.0 / Mass));
procedure Create_Ball
(X : Float; Y : Float; Mass : Float; Velocity : Float; Balls : in out Ball_Array_Type; J : Integer);
type Int_Array is array (Integer range <>) of Integer range 0 .. Buffer_Size;
type Bool_Array is array (Integer range <>) of Boolean;
protected Collision_Manager is
procedure Reset;
procedure Set_Collision (J, K : Integer);
procedure Keep_Immunity (J : Integer);
function Collision_With (J : Integer) return Integer;
function Should_Keep_Immunity (J : Integer) return Boolean;
private
Collision_Vector : Int_Array (1 .. Buffer_Size);
Immunity_Vector : Bool_Array (1 .. Buffer_Size);
end Collision_Manager;
protected body Collision_Manager is
procedure Reset is
begin
Collision_Vector := (others => 0);
Immunity_Vector := (others => False);
end Reset;
procedure Set_Collision (J, K : Integer) is
begin
Collision_Vector (J) := K;
end Set_Collision;
procedure Keep_Immunity (J : Integer) is
begin
Immunity_Vector (J) := True;
end Keep_Immunity;
function Collision_With (J : Integer) return Integer is
begin
return Collision_Vector (J);
end Collision_With;
function Should_Keep_Immunity (J : Integer) return Boolean is
begin
return Immunity_Vector (J);
end Should_Keep_Immunity;
end Collision_Manager;
procedure Create_Graphic (B : in out Ball) is
begin
B.S := New_Circle
(B.X, B.Y, B.Size,
(if B.Size > 15.0 then Blue
elsif B.Size > 10.0 then Green
elsif B.Size > 5.0 then Yellow
elsif B.Size > 2.0 then Magenta
else Red));
end Create_Graphic;
function Collision (B1, B2 : Ball) return Boolean is
Dx, Dy : Float;
Size : Float;
begin
if B1 = Null_Ball or else B2 = Null_Ball then
return False;
end if;
Dx := B1.X - B2.X;
Dy := B1.Y - B2.Y;
Size := B1.Size + B2.Size;
return Dx * Dx + Dy * Dy <= Size * Size;
end Collision;
procedure Bounce (B1, B2 : in out Ball) is
Dx : Float;
Dy : Float;
Length : Float;
Dvx : Float;
Dvy : Float;
Impulse : Float;
begin
Dx := B1.X - B2.X;
Dy := B1.Y - B2.Y;
Length := Sqrt (Dx * Dx + Dy * Dy);
if Length /= 0.0 then
Dx := Dx / Length;
Dy := Dy / Length;
Dvx := B1.Dx - B2.Dx;
Dvy := B1.Dy - B2.Dy;
Impulse := -2.0 * (Dx * Dvx + Dy * Dvy);
Impulse := Impulse / (1.0 / B1.Mass + 1.0 / B2.Mass);
B1.Dx := B1.Dx + Dx * (Impulse / B1.Mass);
B1.Dy := B1.Dy + Dy * (Impulse / B1.Mass);
B2.Dx := B2.Dx - Dx * (Impulse / B2.Mass);
B2.Dy := B2.Dy - Dy * (Impulse / B2.Mass);
end if;
end Bounce;
procedure Explode (Balls : in out Ball_Array_Type; Index : Integer) is
B : Ball := Balls (Index);
V : Float;
Cy : Float;
Sub_Particles : Integer;
begin
Sub_Particles := Integer (Log (X => B.Mass, Base => 2.0) + 1.0);
Total_Ball := Total_Ball - 1;
V := Sqrt (B.Dx * B.Dx + B.Dy * B.Dy);
Cy := 1.0 / 2.0 * B.Mass * V * V;
Delete (Balls (Index).S);
Balls (Index) := Null_Ball;
for J in 1 .. Sub_Particles loop
for K in Balls'Range loop
if Balls (K) = Null_Ball then
Create_Ball
(X => B.X + Random (Seed) * B.Size - B.Size / 2.0,
Y => B.Y + Random (Seed) * B.Size - B.Size / 2.0,
Mass => B.Mass / Float (Sub_Particles),
Velocity => Speed
(Cy / Float (Sub_Particles),
B.Mass / Float (Sub_Particles)),
Balls => Balls,
J => K);
Create_Graphic (Balls (K));
exit;
end if;
end loop;
end loop;
end Explode;
procedure Combine (Balls : in out Ball_Array_Type; J, K : Integer) is
B1 : Ball := Balls (J);
B2 : Ball := Balls (K);
Cy : Float := Cynetic_Energy (B1) + Cynetic_Energy (B2);
begin
Total_Ball := Total_Ball - 2;
Delete (Balls (K).S);
Balls (K) := Null_Ball;
Delete (Balls (J).S);
Create_Ball
(B1.X + (B1.X - B2.X) / 2.0,
B1.Y + (B1.Y - B2.Y) / 2.0,
B1.Mass + B2.Mass,
Speed (Cy, B1.Mass + B2.Mass),
Balls,
J);
Create_Graphic (Balls (J));
end Combine;
procedure Create_Ball
(X : Float; Y : Float; Mass : Float;
Velocity : Float; Balls : in out Ball_Array_Type; J : Integer)
is
B : Ball renames Balls (J);
Angle : Float := Random (Seed) * 2.0 * Pi;
begin
Total_Ball := Total_Ball + 1;
B.X := X;
B.Y := Y;
B.Dx := Cos (Angle) * Velocity;
B.Dy := Sin (Angle) * Velocity;
B.Mass := Mass;
B.Size := Sqrt (B.Mass);
B.Immunity := Base_Immunity;
Collision_Manager.Keep_Immunity (J);
end Create_Ball;
Lines : constant Shape_Array_Type (1 .. 4) :=
(New_Line (-100.0, -100.0, 100.0, -100.0, Blue),
New_Line (-100.0, -100.0, -100.0, 100.0, Blue),
New_Line (100.0, 100.0, 100.0, -100.0, Blue),
New_Line (100.0, 100.0, -100.0, 100.0, Blue));
R : Float;
Balls_Txt : Shape_Id := New_Text (110.0, 90.0, "0", White);
Explode_Txt : Shape_Id := New_Text (110.0, 80.0, "0", White);
Combine_Txt : Shape_Id := New_Text (110.0, 70.0, "0", White);
Combine_Prob : Float := 0.04;
Explode_Prob : Float := 0.02;
Ball_Array : Ball_Array_Type (1 .. Buffer_Size) := (others => Null_Ball);
task type Collision_Detection (Size, Modulus, Ind : Integer) is
entry Compute;
entry Finished;
entry Stop;
end Collision_Detection;
task body Collision_Detection is
Do_Work : Boolean := True;
J : Integer;
begin
while Do_Work loop
select
accept Compute;
J := Ind;
if J = 0 then
J := J + Modulus;
end if;
while J <= Size loop
if Ball_Array (J) /= Null_Ball then
for K in J + 1 .. Ball_Array'Last loop
if Collision (Ball_Array (J), Ball_Array (K)) then
if Ball_Array (J).Immunity = 0
and then Ball_Array (K).Immunity = 0
then
Collision_Manager.Set_Collision (J, K);
end if;
Collision_Manager.Keep_Immunity (J);
Collision_Manager.Keep_Immunity (K);
end if;
end loop;
end if;
J := J + Modulus;
end loop;
accept Finished;
or
accept Stop;
Do_Work := False;
end select;
end loop;
end Collision_Detection;
D1 : Collision_Detection (1200, 4, 0);
D2 : Collision_Detection (1200, 4, 1);
D3 : Collision_Detection (1200, 4, 2);
D4 : Collision_Detection (1200, 4, 3);
begin
for J in 1 .. 20 loop
declare
B : Ball renames Ball_Array (J);
begin
Create_Ball (0.0, 0.0, Random (Seed) * 75.0 + 4.0, 0.5, Ball_Array, J);
Create_Graphic (B);
end;
end loop;
loop
Collision_Manager.Reset;
D1.Compute;
D2.Compute;
D3.Compute;
D4.Compute;
D1.Finished;
D2.Finished;
D3.Finished;
D4.Finished;
for J in Ball_Array'Range loop
if Ball_Array (J) /= Null_Ball then
declare
K : Integer;
begin
if not Collision_Manager.Should_Keep_Immunity (J) then
Ball_Array (J).Immunity := 0;
end if;
K := Collision_Manager.Collision_With (J);
if K /= 0 and then Ball_Array (K) /= Null_Ball then
R := Random (Seed);
if R in 1.0 - Explode_Prob - Combine_Prob
1.0 - Combine_Prob
then
if Ball_Array (J).Mass > Ball_Array (K).Mass then
Explode (Ball_Array, J);
else
Explode (Ball_Array, K);
end if;
elsif R in 1.0 - Combine_Prob .. 1.0 then
Combine (Ball_Array, J, K);
else
Bounce (Ball_Array (J), Ball_Array (K));
end if;
end if;
end;
end if;
end loop;
for J in Ball_Array'Range loop
declare
B : Ball renames Ball_Array (J);
begin
if B /= Null_Ball then
if (B.X - B.Size < -100.0 and then B.Dx < 0.0)
or else (B.X + B.Size > 100.0 and then B.Dx > 0.0)
then
B.Dx := -B.Dx;
end if;
if (B.Y - B.Size< -100.0 and then B.Dy < 0.0)
or else (B.Y + B.Size> 100.0 and then B.Dy > 0.0)
then
B.Dy := -B.Dy;
end if;
B.X := B.X + B.Dx;
B.Y := B.Y + B.Dy;
if B.Immunity > 0 then
B.Immunity := B.Immunity - 1;
end if;
Set_X (B.S, B.X);
Set_Y (B.S, B.Y);
end if;
end;
end loop;
Set_Text (Balls_Txt, "Balls:" & Total_Ball'Img);
Set_Text (Explode_Txt, "Explode Prob:" & Integer (Explode_Prob * 1000.0)'Img & " / 1000");
Set_Text (Combine_Txt, "Combine Prob:" & Integer (Combine_Prob * 1000.0)'Img & " / 1000");
declare
Last_Key : Key_Type := Current_Key_Press;
begin
if To_Character (Last_Key) = 'q' then
Explode_Prob := Explode_Prob - 0.001;
elsif To_Character (Last_Key) = 'w' then
Explode_Prob := Explode_Prob + 0.001;
elsif To_Character (Last_Key) = 'a' then
Combine_Prob := Combine_Prob - 0.001;
elsif To_Character (Last_Key) = 's' then
Combine_Prob := Combine_Prob + 0.001;
end if;
end;
delay 0.01;
end loop;
end Bouncing;
```

**The project file itself**

bouncing.gpr

```
with "/opt/gnatstudio/share/gpr/game_support.gpr";
with "/opt/gnatstudio/share/gpr/gnat_sdl.gpr";
project bouncing is
for Main use("bouncing.adb");
for Object_Dir use "obj";
for Source_Dirs use("src");
end Bouncing;
tually, I had been compile and run some more simple example with the same result:
with Display; use Display;
with Display.Basic; use Display.Basic;
procedure Main is
Ball : Shape_Id := New_Circle
(X => 0.0,
Y => 0.0,
Radius => 10.0,
Color => Blue);
Step : Float := 0.05;
begin
loop
if Get_X (Ball) > 100.0 then
Step := -0.05;
elsif Get_X (Ball) < -100.0 then
Step := 0.05;
end if;
Set_X (Ball, Get_X (Ball) + Step);
delay 0.001;
end loop;
end Main;
```

I had tried to recompile Game_Support, git cloned from here.

I had tried to reinstall GNAT, Gnat Studio, etc.

I CAN run and compile another simple projects, for example with TEXT_IO package, I can run Gnat Studio, but I cannot run this app. I can run analogue, wrote with C++, so the problem is not in my OpenGl 1.3 hardware support.

- System: Arch Linux.
- IDE: Gnat Studio. (Install from AUR).
- Dependencies (SDL, SDL2) - installed.