[Xcb] drawing a font

[Vincent Torri]

I don't think it's needed, as i flush the buffer with XCBSync. Just test
the same program with drawing a point (it works for me, i've just tested).

regards

Vincent TORRI

On Mon, 6 Dec 2004, Jeremy Kolb wrote:

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> I think you need to handle the window's expose event.  When that event
> is received you need to copy the buffer into the window.
>
> Jeremy
>
> Vincent Torri wrote:
> | Hello,
> |
> | Easy question: how to draw a string with xcb ?? i've spent quite a lot of
> | time trying to do that, without success.
> |
> | What i do is a bit like Xlib:
> |
> | * I query a font
> | * I assign the font to a GC
> | * I draw a string (in a pixmap) using this GC
> | * I copy the pixmap onto my window
> |
> | but, nothing is drawn. The code that i use is attached.
> |
> | Does someone see what is wrong ?
> |
> | Vincent TORRI
> |
> |
> | ------------------------------------------------------------------------
> |
> | /* gcc -O2 -Wall `pkg-config --cflags --libs xcb` -o xcb_test_font
> xcb_test_font.c */
> |
> | #include <stdio.h>
> | #include <stdlib.h>
> | #include <string.h>
> |
> | #include <X11/XCB/xcb.h>
> | #include <X11/XCB/xcbint.h>
> |
> | int
> | get_depth(XCBConnection   *c,
> | 	  XCBSCREEN       *root)
> | {
> |   XCBDRAWABLE drawable = { root->root };
> |   XCBGetGeometryRep *geom;
> |   geom = XCBGetGeometryReply(c, XCBGetGeometry(c, drawable), 0);
> |   int depth;
> |
> |   if(!geom)
> |     {
> |       perror("GetGeometry(root) failed");
> |       exit (0);
> |     }
> |
> |   depth = geom->depth;
> |   fprintf(stderr, "Root 0x%lx: %dx%dx%d\n",
> | 	  root->root.xid, geom->width, geom->height, geom->depth);
> |   free(geom);
> |
> |   return depth;
> | }
> |
> | int
> | main (int argc, char *argv[])
> | {
> |   XCBConnection   *c;
> |   XCBSCREEN       *screen;
> |   XCBDRAWABLE      win;
> |   CARD32           mask = 0;
> |   CARD32           values[2];
> |
> |   XCBGCONTEXT      bgcolor, fgcolor;
> |   XCBRECTANGLE     rect = { 0, 0, 300, 300};
> |   CARD32           valgc[2];
> |   XCBDRAWABLE      p;
> |
> |   XCBGCONTEXT gcfont;
> |   CARD32  valfont[1];
> |   XCBFONTABLE fontable;
> |   XCBQueryFontRep *fontrep;
> |   char *fontname;
> |   char *str = "toto";
> |
> |   /* Open the connexion to the X server */
> |   c = XCBConnectBasic ();
> |
> |   /* Get the first screen */
> |   screen = XCBConnSetupSuccessRepRootsIter (c->setup).data;
> |
> |   win.window = screen->root;
> |
> |   fgcolor = XCBGCONTEXTNew(c);
> |   mask = GCForeground | GCGraphicsExposures;
> |   valgc[0] = screen->black_pixel;
> |   valgc[1] = 0; /* no graphics exposures */
> |   XCBCreateGC(c, fgcolor, win, mask, valgc);
> |
> |   bgcolor = XCBGCONTEXTNew(c);
> |   mask = GCForeground | GCGraphicsExposures;
> |   valgc[0] = screen->white_pixel;
> |   valgc[1] = 0; /* no graphics exposures */
> |   XCBCreateGC(c, bgcolor, win, mask, valgc);
> |
> |   p.pixmap = XCBPIXMAPNew (c);
> |   XCBCreatePixmap(c, get_depth (c, screen), p.pixmap, win, 300, 300);
> |   XCBPolyFillRectangle(c, p, bgcolor, 1, &rect);
> |
> |   /* Ask for our window's Id */
> |   win.window = XCBWINDOWNew(c);
> |
> |   /* Create the window */
> |   mask = XCBCWBackPixel | XCBCWEventMask;
> |   values[0] = screen->white_pixel;
> |   values[1] = ExposureMask      | ButtonPressMask  | ButtonReleaseMask |
> |               PointerMotionMask | ButtonMotionMask | EnterWindowMask   |
> |               LeaveWindowMask   | KeyPressMask     | KeyReleaseMask;
> |   XCBCreateWindow (c,                        /* Connection          */
> | 		   get_depth (c, screen),    /* depth               */
> | 		   win.window,               /* window Id           */
> | 		   screen->root,             /* parent window       */
> | 		   0, 0,                     /* x, y                */
> | 		   300, 300,                 /* width, height       */
> | 		   10,                       /* border_width        */
> | 		   InputOutput,              /* class               */
> | 		   screen->root_visual,      /* visual              */
> | 		   mask, values);            /* masks */
> |
> |   /* Map the window on the screen */
> |   XCBMapWindow (c, win.window);
> |
> |   /* The font stuff */
> |
> |   fontable.font = XCBFONTNew (c);
> |   fontname = "*-helvetica-*-12-*";
> |   XCBOpenFont(c, fontable.font, strlen(fontname), fontname);
> |   fontrep = XCBQueryFontReply (c, XCBQueryFont (c, fontable), 0);
> |
> |   mask = GCForeground | GCFont;
> |   valfont[0] = screen->black_pixel;
> |   valfont[1] = fontable.font.xid;
> |   gcfont = XCBGCONTEXTNew (c);
> |   XCBCreateGC (c, gcfont, p, mask, valfont);
> |
> |   XCBPolyText8(c, p, gcfont, 10, 10, strlen(str), str);
> |
> |   XCBCopyArea(c, p, win, fgcolor,
> | 	      0, 0, 0, 0, 300, 300);
> |
> |   XCBSync (c, 0);
> |
> |   free (fontrep);
> |
> |   while (1) {}
> |
> |   return 1;
> | }
> |
> |
> |
> | ------------------------------------------------------------------------
> |
> | _______________________________________________
> | xcb mailing list
> | xcb at lists.freedesktop.org
> | http://lists.freedesktop.org/mailman/listinfo/xcb
>
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