Font/Text

[Sabudda]

Hey, can somone can tell me how to paste text in opengl window... I can't handle this :/
I'm writing program on Free Pascal, I would be greatfull if somone pase code that simple write on the screen some text...

[Traveler]

Have a look at the nehe tutorials.
Alternatively the tutorials (or opengl demos, cant remember which) on sulaco should get you on your way as well.

[WILL]

Well I'm no OpenGL expert, but I have written a font unit of my own which makes use of simple textures. I imagine that OpenGL would probably have to use similar techniques. Unless you really want to work with True Type Fonts or other such formats instead.

There are some issues with using traditional Font formats aswell; Usually you don't get the best cross-platform results they usually are not 100% the same at different resolutions and on other systems depending on what fonts and what format you are using.

The texture image approach is much easier and will gaurentee that you'll get exactly 100% the same look on every system and every platform. Plus you can pretty them up more at design time. It does however take more work to create each new font and may take up more space, depending on the font size and number of characters supported in your font's 'character set(s)'.

Here is my own personal FontUnit.pas that I use with JEDI-SDL in all my games:
[pascal]unit FontUnit;


interface

uses
sdl,
sdlutils,

GraphicsUnit;

const
CharSet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!?.,:;"' + #39 + #92 + '/|+-=_@#$%^&*()' + #123 + #125 + '[]<>';

type
TFont = class(TObject)
FontData: PSDL_Surface;
FontColor: Cardinal;
CharWidth, CharHeight: Integer;

constructor LoadFromFile(Width, Height, Color: Cardinal; FileName: String);
destructor Free;
procedure DrawText(Dest: PSDL_Surface; X, Y: Integer; Text: String);
function GetTextWidth(Text: String): Cardinal;
end;


implementation


function GetCharNum(ch: Char): Integer;
begin
Result := -1;
if (ch < #32) or
((ch > #95) and (ch < #123)) or
(ch > #125) then
Exit;

case (ch) of
'A' : Result := 1;
'B' : Result := 2;
'C' : Result := 3;
'D' : Result := 4;
'E' : Result := 5;
'F' : Result := 6;
'G' : Result := 7;
'H' : Result := 8;
'I' : Result := 9;
'J' : Result := 10;
'K' : Result := 11;
'L' : Result := 12;
'M' : Result := 13;
'N' : Result := 14;
'O' : Result := 15;
'P' : Result := 16;
'Q' : Result := 17;
'R' : Result := 18;
'S' : Result := 19;
'T' : Result := 20;
'U' : Result := 21;
'V' : Result := 22;
'W' : Result := 23;
'X' : Result := 24;
'Y' : Result := 25;
'Z' : Result := 26;
'0' : Result := 27;
'1' : Result := 28;
'2' : Result := 29;
'3' : Result := 30;
'4' : Result := 31;
'5' : Result := 32;
'6' : Result := 33;
'7' : Result := 34;
'8' : Result := 35;
'9' : Result := 36;
'!' : Result := 37;
'?' : Result := 38;
'.' : Result := 39;
',' : Result := 40;
':' : Result := 41;
';' : Result := 42;
'"' : Result := 43;
#39 : Result := 44;
#92 : Result := 45;
'/' : Result := 46;
'|' : Result := 47;
'+' : Result := 48;
'-' : Result := 49;
'=' : Result := 50;
'_' : Result := 51;
'@' : Result := 52;
'#' : Result := 53;
'$' : Result := 54;
'%' : Result := 55;
'^' : Result := 56;
'&' : Result := 57;
'*' : Result := 58;
'(' : Result := 59;
')' : Result := 60;
#123 : Result := 61;
#125 : Result := 62;
'[' : Result := 63;
']' : Result := 64;
'<' : Result := 65;
'>' : Result := 66;
end;
end;


constructor TFont.LoadFromFile(Width, Height, Color: Cardinal; FileName: String);
begin
CharWidth := Width;
CharHeight := Height;
FontColor := Color;
FontData := LoadImage(FileName, True);
end;
destructor TFont.Free;
begin
SDL_FreeSurface(FontData);
end;
procedure TFont.DrawText(Dest: PSDL_Surface; X, Y: Integer; Text: String);
var
i: Integer;
xChar: Integer;
SrcRect, DestRect: TSDL_Rect;
begin
if (Length(Text) > 0) then
begin
for i := 0 to Length(Text) - 1 do
begin
// Find Character tile
xChar := GetCharNum(Text[i + 1]) - 1;

SrcRect := SDLRect(xChar * CharWidth, 0, CharWidth, CharHeight);
DestRect := SDLRect(X + i * CharWidth, Y, CharWidth, CharHeight);
// Draw Letter
SDL_BlitSurface(FontData, @SrcRect, Dest, @DestRect);
end;
end;
end;
function TFont.GetTextWidth(Text: String): Cardinal;
begin
Result := Length(Text) * CharWidth;
end;

end.[/pascal]

Oh yeah ah--free to use... ..give permission... ...freely distribute... [size=9px]*blah blah*[/size]... err--FREE!

[Sly]

Look up BMFont for the best font bitmap generator that I have found. It generates not only the font bitmap, but also a table that tells you where each character is on the texture, how wide and tall each character is, plus the kerning information. Really simple to use and you get a brilliant result.

[Sabudda]

THX!!!

I have one more question. (maybe 2)

1. How to select object (for example if i click on a cube on window somthing is going on)

2. How to disable resizing window



I would be greatfull, if somone paste code in free pascal

[Sly]

Look up 'picking' in OpenGL to select an object.

[Traveler]

You really should visit sulaco as it has a demo, including source about selecting objects .

I assume you already have some code for creating your opengl window. I also assume, you're using the CreateWindowEx function somehere in there.
This page has detailed info about it, including info on how to create for example borderless or non resizable windows.