Java-Gaming.org    
Featured games (81)
games approved by the League of Dukes
Games in Showcase (487)
Games in Android Showcase (112)
games submitted by our members
Games in WIP (553)
games currently in development
News: Read the Java Gaming Resources, or peek at the official Java tutorials
 
    Home     Help   Search   Login   Register   
Pages: [1]
  ignore  |  Print  
  glBitmap()  (Read 1024 times)
0 Members and 1 Guest are viewing this topic.
Offline cborders

Junior Member





« Posted 2005-12-08 21:40:30 »

I am trying to mimic the glBitmap() example in the Red Book, but having no luck!  Here is the important bits of code:
1  
2  
3  
4  
5  
6  
7  
8  
9  
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
25  
26  
27  
28  
29  
30  
31  
32  
33  
34  
35  
36  
37  
38  
39  
40  
41  
42  
43  
44  
45  
46  
47  
48  
49  
HashMap<String, byte[]> font = new HashMap<String, byte[]>(36);

private void buildTable()
{
   font.put("A", new byte[]{(byte)0x70, (byte)0x88, (byte)0x88, (byte)0x88, (byte)0xF8, (byte)0x88, (byte)0x88, (byte)0x00});
   font.put("B", new byte[]{(byte)0xF0, (byte)0x88, (byte)0x88, (byte)0xF0, (byte)0x88, (byte)0x88, (byte)0xF0, (byte)0x00});
   font.put("C", new byte[]{(byte)0x70, (byte)0x88, (byte)0x80, (byte)0x80, (byte)0x80, (byte)0x88, (byte)0x70, (byte)0x00});
   font.put("D", new byte[]{(byte)0xF0, (byte)0x90, (byte)0x88, (byte)0x88, (byte)0x88, (byte)0x90, (byte)0xF0, (byte)0x00});
   font.put("E", new byte[]{(byte)0xF8, (byte)0x80, (byte)0x80, (byte)0xF0, (byte)0x80, (byte)0x80, (byte)0xF8, (byte)0x00});
   font.put("F", new byte[]{(byte)0xF8, (byte)0x80, (byte)0x80, (byte)0xF8, (byte)0x80, (byte)0x80, (byte)0x80, (byte)0x00});
   ...
   font.put("2", new byte[]{(byte)0x70, (byte)0x88, (byte)0x08, (byte)0x10, (byte)0x20, (byte)0x40, (byte)0xF8, (byte)0x00});
   font.put("3", new byte[]{(byte)0xF8, (byte)0x10, (byte)0x20, (byte)0x10, (byte)0x08, (byte)0x88, (byte)0x70, (byte)0x00});
   font.put("4", new byte[]{(byte)0x10, (byte)0x30, (byte)0x50, (byte)0x90, (byte)0xF8, (byte)0x10, (byte)0x10, (byte)0x00});
   font.put("5", new byte[]{(byte)0xF8, (byte)0x80, (byte)0xF0, (byte)0x08, (byte)0x08, (byte)0x88, (byte)0x70, (byte)0x00});
   font.put("6", new byte[]{(byte)0x30, (byte)0x40, (byte)0x80, (byte)0xF0, (byte)0x88, (byte)0x88, (byte)0x70, (byte)0x00});
   font.put("7", new byte[]{(byte)0xF8, (byte)0x08, (byte)0x10, (byte)0x20, (byte)0x40, (byte)0x40, (byte)0x40, (byte)0x00});
   font.put("8", new byte[]{(byte)0x70, (byte)0x88, (byte)0x88, (byte)0x70, (byte)0x88, (byte)0x88, (byte)0x70, (byte)0x00});
   font.put("9", new byte[]{(byte)0x70, (byte)0x88, (byte)0x88, (byte)0x78, (byte)0x08, (byte)0x10, (byte)0x60, (byte)0x00});
}

public ByteBuffer text(String text)
{
   ByteBuffer retBuffer = ByteBuffer.allocateDirect(text.length()*8).order(ByteOrder.nativeOrder());
   byte[] letter;
   
   for(int i = 0; i < text.length(); i++)
   {
      letter = font.get(text.substring(i, i+1).toUpperCase());
      if(letter == null) letter = font.get("*");
      retBuffer.put(letter);
   }
   retBuffer.flip();
   retBuffer.rewind();
   return retBuffer;
}

private void render()
{
   // clear background
  GL11.glClear(GL11.GL_COLOR_BUFFER_BIT | GL11.GL_DEPTH_BUFFER_BIT);
   GL11.glLoadIdentity();
   GL11.glTranslatef(0.0f, 0.0f, -1f);
   
   stringBuffer = text("A");
   
   GL11.glRasterPos2f(0f, 0f);
   GL11.glBitmap(5, 8, 0, 0, 8, 0, stringBuffer);
}


This is what I get:



If I change the
1  
stringBuffer = text("A");
to
1  
stringBuffer = text("AAAAAAAAAA");
I get this:



What am I doing wrong?
Offline cborders

Junior Member





« Reply #1 - Posted 2005-12-09 18:15:12 »

Ok, I figured it out!  I needed to add
1  
GL11.glPixelStorei(GL11.GL_UNPACK_ALIGNMENT, 1);
to my initGL() method.  The I saw that it only displayed the first letter of the string and it was upside down.  Turns out that OpenGL needs to have the bytes specified fromt eh bottom up, not the top down, so I flipped that and got the first letter right side up.  Then I realized that it wasn't stepping through the ByteBuffer so I added the following code to the render() method.
1  
2  
3  
4  
5  
6  
7  
GL11.glRasterPos2f(0f, 0f);
stringBuffer.rewind();
for(int h = 0; h < temp.length(); h++)
{
   GL11.glBitmap(5, 8, 0, 0, 6, 0, stringBuffer);
   for(int i = 0; i < 8; i++) stringBuffer.get();
}


Now it looks like this!

Pages: [1]
  ignore  |  Print  
 
 
You cannot reply to this message, because it is very, very old.

 

Add your game by posting it in the WIP section,
or publish it in Showcase.

The first screenshot will be displayed as a thumbnail.

TehJavaDev (13 views)
2014-08-28 18:26:30

CopyableCougar4 (25 views)
2014-08-22 19:31:30

atombrot (38 views)
2014-08-19 09:29:53

Tekkerue (31 views)
2014-08-16 06:45:27

Tekkerue (31 views)
2014-08-16 06:22:17

Tekkerue (19 views)
2014-08-16 06:20:21

Tekkerue (29 views)
2014-08-16 06:12:11

Rayexar (66 views)
2014-08-11 02:49:23

BurntPizza (42 views)
2014-08-09 21:09:32

BurntPizza (34 views)
2014-08-08 02:01:56
List of Learning Resources
by Longor1996
2014-08-16 10:40:00

List of Learning Resources
by SilverTiger
2014-08-05 19:33:27

Resources for WIP games
by CogWheelz
2014-08-01 16:20:17

Resources for WIP games
by CogWheelz
2014-08-01 16:19:50

List of Learning Resources
by SilverTiger
2014-07-31 16:29:50

List of Learning Resources
by SilverTiger
2014-07-31 16:26:06

List of Learning Resources
by SilverTiger
2014-07-31 11:54:12

HotSpot Options
by dleskov
2014-07-08 01:59:08
java-gaming.org is not responsible for the content posted by its members, including references to external websites, and other references that may or may not have a relation with our primarily gaming and game production oriented community. inquiries and complaints can be sent via email to the info‑account of the company managing the website of java‑gaming.org
Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines | Managed by Enhanced Four Valid XHTML 1.0! Valid CSS!