KSDev's Blog: Using of FireMonkey's Graphics on Linux Server

FmxLinux isn't only UI solution, it is a easy way to use graphics in your web script or server apps.

Installing dependencies to Server

To use graphical features on your server app some dependencies should be installed. You don't need to install whole X11 system to server.

To install dependencies type this in terminal:

sudo apt install libgl1-mesa-glx libglu1-mesa libgtk-3-common libgstreamer1.0 libgstreamer-plugins-base1.0

Writing server script

Common web-server script application is just regular console app. Create new Console Application and then as usual right click on Project in Project Inspector and select "Add FmxLinux" item (only available since FmxLinux 1.17). Next we show full source of simple apache cgi-script which generate PNG image.

Source code

program FmxWebScript;

{$APPTYPE CONSOLE}

uses
System.SysUtils,
System.Types,
System.Classes,
System.UIConsts,
FMX.Types,
FMX.Graphics,
FMX.Utils;

var
B: TBitmap;
Stream: TStream;
Cur: PByte;
I: Integer;
Keys: TStrings;
Text: string;
W, H: Integer;
Query: string;
begin
Query := GetEnvironmentVariable('QUERY_STRING');
if Query.IsEmpty then
begin
Writeln('This is CGI script app, which is run under web server');
Exit;
end;

Keys := TStringList.Create;
Keys.CommaText := Query.Replace('&', ',');

if not TryStrToInt(Keys.Values['width'], W) then
W := 400;
if not TryStrToInt(Keys.Values['height'], H) then
H := 300;

B := TBitmap.Create(W, H);
if Keys.Values['color'] <> '' then
begin
if Keys.Values['color'] = 'random' then
begin
Randomize;
B.Canvas.Fill.Color := $FF000000 or random($FFFFFF);
end
else
B.Canvas.Fill.Color := StringToAlphaColor(Keys.Values['color'])
end
else
B.Canvas.Fill.Color := $FFFF0000;
B.Canvas.FillEllipse(B.BoundsF, 1);
B.Canvas.Stroke.Color := claBlack;
B.Canvas.DrawEllipse(B.BoundsF, 1);

B.Canvas.Fill.Color := $FF000000;
Text := 'FmxLinux';
if Keys.Values['text'] <> '' then
Text := Keys.Values['text'].Replace('%20', ' ');
B.Canvas.FillText(B.BoundsF, Text, False, 1, [], TTextAlign.Center);

Stream := TMemoryStream.Create;
B.SaveToStream(Stream);

Writeln('Content-type: image/png');
Writeln('Content-length: ' + Stream.Size.ToString);
Writeln;

Cur := TMemoryStream(Stream).Memory;
for I := 0 to Stream.Size - 1 do
begin
Write(Utf8Char(Cur^));
Inc(Cur);
end;
end.