Need help~add a texture on the plane

OpenGL Development JOGL Development
#1

Hi~~
I want to add a texture on a plane with gl.glTexImage2D(…),but I dont understand how to change a image to byte array.Can anyone post this code.
Thank~

#2

Firstly load the texture into a ByteBuffer

public void loadTexture()
{
      BufferedImage buff=null;
  int[] img = null;
      try{
      buff=ImageIO.read(new BufferedInputStream(this.getClass().getResourceAsStream("yourfilename")));
      }catch(IOException ioex){System.out.println(ioex.toString());}
      Raster r = buff.getRaster();
  img = r.getPixels(0, 0, buff.getWidth(), buff.getHeight(), img);
  texture = ByteBuffer.allocateDirect(buff.getWidth() * buff.getHeight() * 3);
  for (int y = 0; y < buff.getHeight(); y++)
    for (int x = 0; x < buff.getWidth(); x++)
                  {
      texture.put((byte) img[(y * buff.getWidth() + x) * 3]);
      texture.put((byte) img[(y * buff.getWidth() + x) * 3 + 1]);
      texture.put((byte) img[(y * buff.getWidth() + x) * 3 + 2]);
      }
   tWidth = buff.getWidth();
   tHeight = buff.getHeight();
}

And then use the teximage2D to actually link the buffer to a texture id number and set its parameters:

            
int textures[];
gl.glGenTextures(1,textures);
gl.glBindTexture(GL.GL_TEXTURE_2D, textures[0]);
            loadTexture();
            gl.glTexImage2D(GL.GL_TEXTURE_2D, 0, 3, tWidth, tHeight,0, GL.GL_RGB, GL.GL_UNSIGNED_BYTE, texture);
            gl.glTexParameteri(GL.GL_TEXTURE_2D,GL.GL_TEXTURE_MIN_FILTER,GL.GL_LINEAR);
             gl.glTexParameteri(GL.GL_TEXTURE_2D,GL.GL_TEXTURE_MAG_FILTER,GL.GL_LINEAR);

Hope this can help

#3

thank a lot~~
what package you use~~eg ByteBuffer.

#4

these code seem have problem~

[tr][td]
System.out.println(texture);
for (int y = 0; y < buff.getHeight(); y++){
for (int x = 0; x < buff.getWidth(); x++){
texture.put((byte) img[(y * buff.getWidth() + x) * 3]);
texture.put((byte) img[(y * buff.getWidth() + x) * 3 + 1]);
texture.put((byte) img[(y * buff.getWidth() + x) * 3 + 2]);
}
}[/td][/tr]

cant run…
um… why need *3

#5

this code normally works perfectly fine for me.

maybe the problem comes from your line

system.out.println(texture);

that will crash if it even happen to compile

if you want to check texture you should do

system.out.println(texture.toString());

instead.

Concerning the reason of why * 3 i have no idea as i picked up the method in a tutorial ;D

#6

*3 must be related to RGB on 8 bits don’t youi think?