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Issue of the Implementation # D0089

Brief

Invocation of the interfaces glColor3i, glColor3iv does not set implicitly the value of the alpha component

Detailed Description

The standard states: "glColor sets a new four-valued RGBA color. glColor has two major variants: glColor3 and glColor4. glColor3 variants specify new red, green, and blue values explicitly and set the current alpha value to 1.0 (full intensity) implicitly.", but invocation of the glColor3i, glColor3iv interfaces does not set the alpha value to 1.0 (full intensity).

Problem location(s) in the standard

Linux Standard Base Desktop Specification 3.2, Chapter 7. Libraries, 7.1.2.1 Interfaces for OpenGL that refers OpenGL Reference Pages, glColor

Example

#include <GL/gl.h>
#include <GL/glx.h>
#include <stdio.h>

typedef struct _TGLWindow
{
    Display *dpy;
    GLXContext cx;
    XVisualInfo *vi;
    Window win;
    GLXWindow  glxWin;
    GLXFBConfig *fbConfigs;
    int width;
    int height;
} TGLWindow;

static int tSingleBuffer_1_2[] = {GLX_RGBA,
                                    GLX_RED_SIZE,       1,
                                    GLX_GREEN_SIZE,     1,
                                    GLX_BLUE_SIZE,      1,
                                    None};
static int tDoubleBuffer_1_2[] = {GLX_RGBA,
                                    GLX_DOUBLEBUFFER,
                                    GLX_RED_SIZE,       1,
                                    GLX_GREEN_SIZE,     1,
                                    GLX_BLUE_SIZE,      1,
                                    None};


static Bool WaitForNotify(Display *d, XEvent *e, char *arg) {
    if (e->type == CreateNotify)
    {
        printf("Window was successfully created.");
    }
    return (e->type == MapNotify) && (e->xmap.window == (Window)arg);
}
TGLWindow tWnd;

int main() {
   int errBase = 0;
   int evtBase = 0;
   GLboolean bStatus;
   tWnd.dpy = NULL;
   tWnd.vi = NULL;
   tWnd.fbConfigs = NULL;
   tWnd.cx = 0;
   tWnd.height = 600;
   tWnd.width = 800;
    
   /* get a connection */
   tWnd.dpy = XOpenDisplay(0);

   if (!tWnd.dpy)
   {
        printf ("XOpenDisplay () returned NULL.");
        return -1;
   }
    if (glXQueryExtension(tWnd.dpy, &errBase, &evtBase) == GL_FALSE)
    {
        printf("The GLX extension is not supported by the server.");
        printf("error base is %d, event base is %d.", errBase, evtBase);
        return -1;
    }

    Colormap cmap;
    XSetWindowAttributes swa;
    XEvent event;
    int *attrList = tSingleBuffer_1_2;
    tWnd.vi = glXChooseVisual(tWnd.dpy, DefaultScreen(tWnd.dpy), attrList);
    if (tWnd.vi == NULL)
    {
        printf("glXChooseVisual() returned NULL");
        return -1;
    }

    /* create a GLX context */
    tWnd.cx = glXCreateContext(tWnd.dpy, tWnd.vi, 0, GL_TRUE);

    /* create a color map */
    cmap = XCreateColormap(tWnd.dpy, RootWindow(tWnd.dpy, tWnd.vi->screen),
                tWnd.vi->visual, AllocNone);

    /* create a window */
    swa.colormap = cmap;
    swa.border_pixel = 0;
    swa.event_mask = StructureNotifyMask;
    tWnd.win = XCreateWindow(tWnd.dpy, RootWindow(tWnd.dpy, tWnd.vi->screen), 0,
                          0, tWnd.width, tWnd.height,
                          0, tWnd.vi->depth, InputOutput,tWnd.vi->visual,
                          CWBorderPixel|CWColormap|CWEventMask,
                          &swa);
    XMapWindow(tWnd.dpy, tWnd.win);
    XIfEvent(tWnd.dpy, &event, WaitForNotify, (char*)tWnd.win);

    /* connect the context to the window */
    glXMakeCurrent(tWnd.dpy, tWnd.win, tWnd.cx);
    
    
    GLint params[] = {10, 10300, 14230};
    
    GLint retParams[4];
    
    glColor3i (params[0], params[1], params[2]);

    glGetIntegerv (GL_CURRENT_COLOR, retParams);
        
    printf ("After invocation of glColor3i(%d, %d, %d) interface, the current "
        "color was set to (%d, %d, %d, %d)", params[0], params[1], params[2], 
        retParams[0], retParams[1], retParams[2], retParams[3]);

    return 1;
}

Component

Mesa 7.0.2 or earlier

Status

Fixed in Mesa 7.0.3

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