Text overlay not working with Xorg modesetting driver - c++

Question

This is a piece of code which displays text and background rectangle When this piece of code is run with Intel as default XORG driver everything works fine both text and rectangle are being displayed,whereas when i switch to the Modesetting driver only the background rectangle is seen and text is not being displayed
#include <iostream>
#include<unistd.h>
#include <sstream>
#include <string>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/Xft/Xft.h>
#include <X11/extensions/XShm.h>
#include <sys/ipc.h>
#include <sys/shm.h>
using namespace std;
int main()
{
Display *display = XOpenDisplay(NULL);
Screen *scn = DefaultScreenOfDisplay(display);
int screen_num = DefaultScreen(display);
int screen_width = DisplayWidth(display, screen_num);
int screen_height = DisplayHeight(display, screen_num);
int defaultScnDepth = DefaultDepthOfScreen(scn);
Visual *visual = DefaultVisualOfScreen(scn);
Window window=XCreateSimpleWindow(display,RootWindow(display,screen_num), 50, 50, 400, 400, 2 ,BlackPixel(display,screen_num),WhitePixel(display,screen_num));
//XFlush(display)
XMapWindow(display, window);
XShmSegmentInfo shmInfo;
XImage *xImage;
Pixmap backPixmap;
(xImage) = XShmCreateImage(display, visual, defaultScnDepth, ZPixmap, NULL, &shmInfo, screen_width, screen_height);
shmInfo.shmid = shmget(IPC_PRIVATE, (xImage)->bytes_per_line * (xImage)->height, IPC_CREAT | 0777);
shmInfo.shmaddr = (char *) shmat(shmInfo.shmid, 0, 0);
xImage->data = shmInfo.shmaddr;
shmInfo.readOnly = False;
XShmAttach(display, &shmInfo);
(backPixmap) = XShmCreatePixmap(display, window, (char *) (shmInfo.shmaddr), &shmInfo, (xImage)->width, (xImage)->height, (xImage)->depth);
XGCValues values;
GC gc = XCreateGC(display, backPixmap, 0, &values);
XSync(display, false);
Drawable drawable =backPixmap;
visual = DefaultVisual(display, DefaultScreen(display));
Colormap colormap = XCreateColormap(display, window, visual, AllocNone);
//gc = XCreateGC(display, drawable, 0, &values);
//XFlushGC(display, gc);
const char *text = "Hello";
XftDraw *xftDraw = NULL;
XRenderColor xrFGColor, xrBGColor;
XftColor xftFGColor, xftBGColor;
XftFont *font = NULL;
font = XftFontOpenName( display, DefaultScreen( display ), "morpheus-18" );
xftDraw = XftDrawCreate(display, drawable, visual, colormap);
int nextLineStartY, rectYRef;
bool firstIte;
unsigned int rectX, rectY, rectWidth, rectHeight;
nextLineStartY = 0; rectYRef = 0;
firstIte = true;
rectX = 0; rectY = 0; rectWidth = 0; rectHeight = 0;
std::istringstream strStream(text);
std::string line;
while(std::getline(strStream, line))
{
const char *lineText = line.c_str();
if(*lineText == '\0')
{
nextLineStartY += rectHeight + 1;
continue;
}
const char *text = lineText;
XGlyphInfo extents;
XftTextExtents8(display, font, (XftChar8 *)text, strlen(text), &extents);
unsigned int width = extents.width;
unsigned int height = extents.height;
int ascent = extents.y;
int lBearing = extents.x;
rectX = 50 - lBearing - 1;
rectY = 50 - ascent - 1;
rectWidth = width + 2 * 1;
rectHeight = height + 5 + 1;
if(firstIte)
{
rectYRef = rectY;
firstIte = false;
}
int diff = rectYRef - rectY;
rectY += nextLineStartY + diff;
nextLineStartY += rectHeight + 1;
if(1)
{
xrBGColor.red = 0x7fff;
xrBGColor.green= 0x7fff;
xrBGColor.blue = 0x7fff;
xrBGColor.alpha= 0xffff;
XftColorAllocValue(display, visual, colormap, &xrBGColor, &xftBGColor);
// Draw background fill rectangle
XftDrawRect(xftDraw, &xftBGColor, rectX, rectY, rectWidth, rectHeight);
XftColorFree(display, visual, colormap, &xftBGColor);
}
xrFGColor.red = 0xbfff;
xrFGColor.green = 0xbfff;
xrFGColor.blue = 0xbfff;
xrFGColor.alpha= 0xffff;
XftColorAllocValue(display, visual, colormap, &xrFGColor, &xftFGColor);
// Overlay Text
XftDrawString8(xftDraw, &xftFGColor, font, 50, 50, (XftChar8 *) text, strlen(text));
XColor xForeColor;
xForeColor.red = 0xafff;
xForeColor.green = 0xafff;
xForeColor.blue = 0xffff;
if(XAllocColor(display,colormap,&xForeColor))
XSetForeground(display,gc,xForeColor.pixel);
XftColorFree(display, visual, colormap, &xftFGColor);
XFreeColors(display, colormap, &(xForeColor.pixel), 1, 0);
}
XftDrawDestroy(xftDraw);
XShmPutImage(display, window, gc, xImage, 0, 0, 0, 0, 400, 400, false);
XSync(display, false);
getchar();
}
I tried out other drivers too, with the radeon drivers i see a X error that shared pixmaps are not supported while i don't see any such error for the modesetting driver.
Has this something to do with the shared pixmaps, if yes how should i make it work with the modesetting driver.
I have been stuck on this for a while now, any help would be appreciated.