SGI Developer Toolbox 6.1/SGI Developer Toolbox 6.1 - Disc 1.iso/toolbox/src/tutorials/custEducation/opengl2/demos/oglextensions.c

C/C++ Source or Header | 1996-11-11 | 4.4 KB | 196 lines

/* Copyright (c) Silcon Graphics, Inc. 1995 */

/* oglextensions.c
 * Prints out the GL, GLX and GLU extensions available
 * on the local machine.
 *
 *    Usage: oglextensions [-display <display>]
 */
#include <GL/glx.h>
#include <GL/gl.h>
#include <GL/glu.h>
#include <stdio.h>
#include <string.h>

int visual_request[] = { None }; /* don't need much of a visual */

int
main(int argc, char **argv)
{
    char *display_name = NULL;
    const GLubyte *string;
    Display       *dpy;
    int           screen_num;
    int           major, minor;
    int           dontcare; /* for returned arguments we don't care about */
    XVisualInfo   *vis;
    GLXContext    ctx;
    Window        root,  win;
    Colormap      cmap;
    XSetWindowAttributes swa;
    XEvent        event;

    /* parse arguments */
    if (argc > 1) {
        if(!strcmp(argv[1],"-display"))
            display_name = argv[2];
        else {
            fprintf(stderr, "Usage: %s [-display <display>]\n",
                argv[0]);
            return -1;
        }
    }

    /* get display */
    if (!(dpy = XOpenDisplay(display_name))) {
        fprintf(stderr,"Error: XOpenDisplay() failed.\n");
        return -1;
    }

    /* does the server know about OpenGL & GLX? */
    if(!XQueryExtension(dpy, "GLX", &dontcare, &dontcare, &dontcare)) {
        fprintf(stderr,
            "This system does not appear to support OpenGL\n");
        return -1;
    }


    /* find the glx version */
    if(glXQueryVersion(dpy, &major, &minor))
        printf("GLX Version: %d.%d\n", major, minor);
    else {
        fprintf(stderr, "Error: glXQueryVersion() failed.\n");
        return -1;
    }

    /* get screen number */
    screen_num = DefaultScreen(dpy);

    /* This #ifdef isn't redundant. It keeps the build from breaking
    ** if you are building on a machine that has an old (1.0) version
    ** of glx.
    **
    ** This program could still be *run* on a machine that has an old
    ** version of glx, even if it was *compiled* on a version that has
    ** a new version.
    **
    ** If compiled on a system with an old version of glx, then it will
    ** never recognize glx extensions, since that code would have been
    ** #ifdef'ed out.
    */
#ifdef GLX_VERSION_1_1

    /*
    ** This test guarantees that glx, on the display you are inquiring,
    ** suppports glXQueryExtensionsString().
    */
    if(minor > 0 || major > 1)
        string = glXQueryExtensionsString(dpy, screen_num);
    else
        string = "";

    if(string)
        printf("GLX Extensions (client & server): %s\n\n",
            string);
    else {
        fprintf(stderr, "Error: glXQueryExtensionsString() failed.\n");
        return -1;
    }

#endif

    /* get any valid OpenGL visual */
    if (!(vis = glXChooseVisual(dpy, screen_num, visual_request)))  {
        fprintf(stderr,"Error: glXChooseVisual() failed.\n");
        return -1;
    }

    /* get context */
    ctx = glXCreateContext(dpy,vis,0,GL_TRUE);

    /* root window */
    root = RootWindow(dpy,vis->screen);

    /* get RGBA colormap */
    cmap = XCreateColormap(dpy, root, vis->visual, AllocNone);

    /* get window */
    swa.colormap = cmap;
    swa.border_pixel = 0;
    swa.event_mask = StructureNotifyMask;
    win = XCreateWindow(dpy, root, 0, 0, 1, 1, 0, vis->depth,
                InputOutput,vis->visual,
                CWBorderPixel|CWColormap|CWEventMask,
                &swa);

    glXMakeCurrent(dpy,win,ctx);

    string = glGetString(GL_VERSION);
    if(string)
        printf("OpenGL Version: %s\n", string);
    else {
        fprintf(stderr, "Error: glGetString(GL_VERSION) failed.\n");
        return -1;
    }

    string = glGetString(GL_RENDERER);

    if(string)
        printf("OpenGL Renderer: %s\n", string);
    else {
        fprintf(stderr, "Error: glGetString(GL_RENDERER) failed.\n");
        return -1;
    }

    string = glGetString(GL_EXTENSIONS);

    if(string)
        printf("OpenGL Extensions: %s\n\n", string);
    else {
        fprintf(stderr, "Error: glGetString(GL_EXTENSIONS) failed.\n");
        return -1;
    }

    /*
    ** This #ifdef prevents a build failure if you compile on an a
    ** machine with an old GLU library.
    **
    ** If you build on a pre GLU 1.1 machine, you will never be able
    ** to get glu info, even if you run on a GLU 1.1 or latter machine,
    ** since the code has been #ifdef'ed out.
    */

#ifdef GLU_VERSION_1_1

    /*
    ** If the glx version is 1.1 or latter, gluGetString() is guaranteed
    ** to exist.
    */
    if(minor > 0 || major > 1)
        string = gluGetString(GLU_VERSION);
    else
        string = "1.0";

    if(string)
        printf("GLU Version: %s\n", string);
    else {
        fprintf(stderr, "Error: gluGetString(GLU_VERSION) failed.\n");
        return -1;
    }

    if(minor > 0 || major > 1)
        string = gluGetString(GLU_EXTENSIONS);
    else
        string = "";

    if(string)
        printf("GLU Extensions: %s\n\n", string);
    else {
        fprintf(stderr,
            "Error: gluGetString(GLU_EXTENSIONS) failed.\n");
        return -1;
    }
#endif
    return 0;
}