Texture from file

[zeedee]

Hi! my question is in the title I show a source in win32 borland c++:

 bitmap = new Graphics::TBitmap;
    bitmap->LoadFromFile("red.bmp");
    GLubyte bits[64][64][4];
    for(int i = 0; i < 64; i++)
    {
    	for(int j = 0; j < 64; j++)
        {
            bits[i][j][0]= (GLbyte)GetRValue(bitmap->Canvas->Pixels[i][j]);
            bits[i][j][1]= (GLbyte)GetGValue(bitmap->Canvas->Pixels[i][j]);
            bits[i][j][2]= (GLbyte)GetBValue(bitmap->Canvas->Pixels[i][j]);
            bits[i][j][3]= (GLbyte)255;
        }
    }
 

so that is what i want to do in linux, maybe with .jpg or .png images.

thanx

[Azdo]

Use libpng or libjpg. They are installed on most Linux systems. It wouldn’t very hard follow its documentation and they’ll save you from many troubles. You can also use SDL_Image if you are using SDL in order to load the textures directly from .jpg or .png files.

[zeedee]

Thanx! I try it.

[zeedee]

I can’t find the libjpg in the gentoo portage:(

[T101]

It’s probably libjpeg

[zeedee]

NO it’s only “jpeg”. Interesting…

[Azdo]

Originally posted by zeedee:
NO it’s only “jpeg”. Interesting…
Make sure you also install the development packages e.g.: .h files and import libraries. On my system:

$> rpm -qa | grep jpeg
libjpeg62-6b-26mdk
libjpeg62-devel-6b-26mdk

The first one contains the dynamic libraries; the second, header files and all the stuff needed to compile.

[glBug]

most of the GNU/Linux distributions come with a great library called “GdkPixbuf”.

look if it is installed on your system:
pkg-config --list-all | grep “GdkPixbuf”

if it is installed you will get the following result:
gdk-pixbuf-xlib-2.0 GdkPixbuf Xlib - GdkPixbuf rendering for Xlib
gdk-pixbuf-2.0 GdkPixbuf - Image loading and scaling

and it means you can use it:

//…
GdkPixbuf* pixbuf = NULL;

//…
pixbuf = gdk_pixbuf_new_from_file ("/path/to/textures/texture_256x256.png", &error );

const guchar* pixels = gdk_pixbuf_get_pixels(pixbuf);

glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 256, 256, 0, GL_RGB, GL_UNSIGNED_BYTE, (GLvoid*)pixels );

//…

GdkPixbuf lib will load you .png, .bmp, .jpg, etc.

[Shukun_no_Haifun]

I can’t find the libjpg in the gentoo portage:(
Just install it yourself, then. LibPNG is rather easy to compile/install (note that you do need zlib as well). Heck, I installed it on my MinGW/MSYS Win32 box.

[system]

If you’re using Qt, you get PNG & JPEG support via Qt’s QImage that can easily be used to load your images.