viUnixCode

#include "viUn.h"

/* Errors */
const char VI_UN_ERR_X_CON[] = "VI ERROR: Cannot connect to X Server.\n";
const char VI_UN_ERR_X_VISINFO[] = "VI ERROR: No appropriate visual area found for X server.\n";
const char VI_UN_ERR_X_NOT_INITIALIZED[] = "VI ERROR: X not initialized. Please initialize the X server before checking the event manager.";
const char VI_UN_ERR_X_COLORMAP_FAIL[] = "VI ERROR: X failed to create colormap.";
const char VI_UN_ERR_GLX_CONFIGFAIL[] = "VI ERROR: GLX failed to obtain configuration information for GLX_USE_GL, or GLX_USE_GL has returned false";


/* Succes Confirmations */
const char VI_UN_SUCCESS_VISINFO[] = "VI SUCCESS: Appropriate visual info found - %p ";

/* Title Strings */
const char VI_UN_DEF_WIN_NAME[] = "( Powered by Virtual Interface ) ( Unix )";

Display*                dp;
Window                  root;
GLint                   attributes[] = { GLX_RGBA, GLX_DEPTH_SIZE, 24, GLX_DOUBLEBUFFER, None };
XVisualInfo*            visualInfo;
Colormap                colorMap;
XSetWindowAttributes    setWindowAtt;
Window                  win;
GLXContext              glxContext;
GLXContext              glxContext2;
XWindowAttributes       xWinAtt;

void viUnInitXAndContext( void )
{
    dp = XOpenDisplay( NULL );

    if ( dp == NULL )
    {
        puts( VI_UN_ERR_X_CON );
        exit( 0 );
    }

    root = DefaultRootWindow( dp );

    visualInfo = glXChooseVisual( dp, 0, attributes );

    if ( !visualInfo )
    {
        puts( VI_UN_ERR_X_VISINFO );
        exit( 0 );
    }
    else
    {
        printf( VI_UN_SUCCESS_VISINFO, ( void* )visualInfo->visualid );
    }

    colorMap = XCreateColormap( dp, root, visualInfo->visual, AllocAll );

    if ( !colorMap )
    {
        puts( VI_UN_ERR_X_COLORMAP_FAIL );
        exit( 0 );

    }

    int val;

    int success = glXGetConfig( dp, visualInfo, GLX_USE_GL, &val );

    if ( success != 0 )
    {
        puts( VI_UN_ERR_GLX_CONFIGFAIL );
        exit( 0 );
    }

    setWindowAtt.colormap = colorMap;
    setWindowAtt.event_mask = ExposureMask | KeyPressMask;

    win = XCreateWindow( dp, root, 0, 0, 600, 600, 0, visualInfo->depth, InputOutput, visualInfo->visual, CWColormap | CWEventMask, &setWindowAtt );

    XMapWindow( dp, win );

    XStoreName( dp, win, VI_UN_DEF_WIN_NAME );

    glxContext = glXCreateContext( dp, visualInfo, NULL, GL_TRUE );

    glXMakeCurrent( dp, win, glxContext );

#define VI_X_INITIALIZED 1

}

void viUnInitGL( void )
{

#ifndef VI_X_INITIALIZED
    puts( VI_UN_ERR_X_NOT_INITIALIZED );
    exit( 1 );
#endif

    glEnable( GL_DEPTH_TEST );
}

void viUnHandleEventMessageDraw( XEvent* event, void ( *DrawFunction )( void ) )
{
#ifndef VI_X_INITIALIZED
    puts
            ( VI_UN_ERR_X_NOT_INITIALIZED );
    exit( 0 );
#endif

    XNextEvent( dp, event );

    switch ( event->type )
    {
        case Expose:

            XGetWindowAttributes( dp, win, &xWinAtt );
            glViewport( 0, 0, xWinAtt.width, xWinAtt.height );

            DrawFunction();

            glXSwapBuffers( dp, win );

            break;

        case KeyPress:

            char string[ 25 ];

            int len;

            KeySym keysym;

            len = XLookupString( &event->xkey, string, 25, &keysym, NULL );

            if ( len < 0 )
            {
                if( string[ 0 ] == 'r' )
                {
                        string[ 0 ] = 'n';
                }

                    fputs( string, stdout );
            }

            switch( keysym )
            {
                case XK_Escape:

                    glXMakeCurrent( dp, None, NULL );
                    glXDestroyContext( dp, glxContext );

                    XDestroyWindow( dp, win );

                    XCloseDisplay( dp );

                    exit( 0 );

                    break;
            }



            break;

        case KeyRelease:

            break;

    }

}

void viUnTestGL( void )
{
    glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );

    glLoadIdentity();

    glTranslatef( 0.0f, 0.0f, -10.0f );

    const int size = 3;

    int verts[ 4 ][ 3 ] =
    {
        { size, size, size },
        { -size, size, size },
        { -size, -size, size },
        { size, -size, size }
    };

    glColor4f( 1.0f, 0.0f, 0.0f, 1.0f );

    glDrawElements( GL_QUADS, 1, GL_UNSIGNED_BYTE, verts );

}