PCX over mesh

paul

Unregistered

Post: #1

Jul 27, 2005 — 04:32 AM

Hy,
i have a lot of questions about how opengl manipolate PCX (my texture) over a mesh:

i must to develop a small opengl project: ther's a girl that mov's when you press the top row. I have already loaded a girl (mesh.ani) and now i must to load file PCX ( my texture) into the mesh. To do i use a class Coni3DPCX and method LoadPCX that permits to load PCX correctly (but i don't see nothing!!).
The problem is: why i cannot display a texture? how i can to put this texture in the mesh? Which of methods i'v must to use?

The function LoadPCX is:

Code:

int Cone3DPCX::LoadPCX(char *filename) 

{ 

  FILE *hTexFile = fopen( filename, "rb" ); 

  /* check the file open command */ 

  if( hTexFile != NULL ) 

  { 

    int imgWidth,width,height, imgHeight, texFileLen, imgBufferPtr, i; 

    pcxHeader *pcxPtr; 

    unsigned char *imgBuffer, *texBuffer, *pcxBufferPtr, *paletteBuffer; 

    /* find length of file */ 

    fseek( hTexFile, 0, SEEK_END ); 

    texFileLen = ftell( hTexFile ); 

    fseek( hTexFile, 0, SEEK_SET ); 

    /* read in file */ 

    texBuffer = (unsigned char *)malloc( texFileLen+1 ); 

    fread( texBuffer, sizeof( char ), texFileLen, hTexFile ); 

    /* get the image dimensions */ 

    pcxPtr = (pcxHeader *)texBuffer; 

    imgWidth = pcxPtr->size[0] - pcxPtr->offset[0] + 1; 

    imgHeight = pcxPtr->size[1] - pcxPtr->offset[1] + 1; 

      /* image starts at 128 from the beginning of the buffer */ 

    imgBuffer = (unsigned char *)malloc( imgWidth * imgHeight ); 

    imgBufferPtr = 0; 

    pcxBufferPtr = &texBuffer[128]; 

    /* decode the pcx image */ 

    while( imgBufferPtr < (imgWidth * imgHeight) ) 

    { 

      if( *pcxBufferPtr > 0xbf ) 

      { 

        int repeat = *pcxBufferPtr++ & 0x3f; 

        for( i=0; i<repeat; i++ ) 

        { 

          imgBuffer[imgBufferPtr++] = *pcxBufferPtr; 

        } 

      } else { 

        imgBuffer[imgBufferPtr++] = *pcxBufferPtr; 

      } 

      pcxBufferPtr++; 

    } 

    /* read in the image palette */ 

    paletteBuffer = (unsigned char *)malloc( 768 ); 

    for( i=0; i<768; i++ ) 

      paletteBuffer[i] = texBuffer[ texFileLen-768+i ]; 

    width=imgWidth; 

    height=imgHeight; 

    /* now create the OpenGLure */ 

    { 

      int i, j; 

      imageData = (unsigned char *)malloc( width * height * 3 ); 

      for (j = 0; j < imgHeight; j++) 

      { 

        for (i = 0; i < imgWidth; i++) 

        { 

          imageData[3*(j * width + i)+0] 

            = paletteBuffer[ 3*imgBuffer[j*imgWidth+i]+0 ]; 

          imageData[3*(j * width + i)+1] 

            = paletteBuffer[ 3*imgBuffer[j*imgWidth+i]+1 ]; 

          imageData[3*(j * width + i)+2] 

            = paletteBuffer[ 3*imgBuffer[j*imgWidth+i]+2 ]; 

        } 

      } 

    } 

    /* cleanup */ 

    free( paletteBuffer ); 

    free( imgBuffer ); 

     gluBuild2DMipmaps(

                   GL_TEXTURE_2D,

                   GL_RGB,

                   width,height, 

                   GL_RGB,

                   GL_UNSIGNED_BYTE,

                   imageData

                   );

    glGenTextures(1, &texID); 

    glBindTexture(GL_TEXTURE_2D, texID); 

    glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR ); 

    glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR ); 

    glTexImage2D(GL_TEXTURE_2D,0,3,width,height,0,GL_RGB, 

    GL_UNSIGNED_BYTE,imageData); 

    bpp=24; 

//But if the file didn't load, then we'll return zero. Else we'll return 1. 

  } else { 

    /* skip the texture setup functions */ 

    return 0; 

  } 

  return 1; 

}

Is enought to display texture but i cannot see nothing!!

Thanks for all
DM

Leisure Suit Lurie

Moderator

Posts: 529
Joined: 2003.03

Post: #2

Jul 27, 2005 — 05:05 AM

I think you need glEnable(GL_TEXTURE_2D) also

"Yes, well, that's the sort of blinkered, Philistine pig-ignorance I've come to expect from you non-creative garbage."

paul

Unregistered

Post: #3

Jul 27, 2005 — 09:50 AM

Ok, i'v already try to add glEnable(--) but nothing.

Questions:
-To display the texture is correct the function that i use (Load PCX)?
-Once texture is loaded automatically sets on the mesh? If not, where e how i must to do?

thanks

Leisure Suit Lurie

Moderator

Posts: 529
Joined: 2003.03

Post: #4

Jul 27, 2005 — 02:46 PM

Does the model have texture coordinates(uvs)?

If you don't know what either of those things are, maybe you should read up on OpenGL texturing.

http://www.spacesimulator.net/tut3_texturemapping.html

"Yes, well, that's the sort of blinkered, Philistine pig-ignorance I've come to expect from you non-creative garbage."

paul

Unregistered

Post: #5

Jul 28, 2005 — 03:55 AM

Yes, i have texture coordinates in the mesh file. The mesh file is .ani and so:
v1 v2 v3 -- -- -- -- -- -- in each row there are 3 vertex and 6 texture coordanates.
-I read the mesh file and memorize the face, the vertex and the texture coordinates;
-I read the texture file (procedure on the previous post)
-I connect the texture coordinates with the vertex coordinates:

for(------)
glTexCoord2d(u,v)
glVertex3f(--vertex1--)
glTexCoord2d(u,v)
glVertex3f(--vertex2--)
glTexCoord2d(u,v)
glVertex3f(--vertex3--)

but nothing is displayed.
What i must to do? If you want i send you the function that i use to read a mesh file & texture file.
Thanks

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