Creating a texture on run time using data for OpenGL - c++

Question

I currently have some heat-map data in a database. I was successful in creating painting a heat-map using the same data [using some vertex shading] onto a plane. Example:
Heat-Map Image example for openGL
Name: Capture.jpg
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Now, the problem is that I am currently using something like :
glBegin(GL_QUADS);
glColor4ub(point1.color.red(), point1.color.green(), point1.color.blue(), transparency);
glVertex3d(point1.xCood - 750, point1.yCood - 750, 0);
glColor4ub(point2.color.red(), point2.color.green(), point2.color.blue(), transparency);
glVertex3d(point2.xCood - 750, point2.yCood - 750, 0);
glColor4ub(point3.color.red(), point3.color.green(), point3.color.blue(), transparency);
glVertex3d(point3.xCood - 750, point3.yCood - 750, 0);
glColor4ub(point4.color.red(), point4.color.green(), point4.color.blue(), transparency);
glVertex3d(point4.xCood - 750, point4.yCood - 750, 0);
glEnd();
And what this does [at least in my theory] is that it creates another layer over the existing plane. This causes code on clicking the plane below to be rendered useless. Changing the existing code too much is not an option right now as I do not have access to edit it. I found that if I draw a texture (rather than color a plane) on the old plane, the code stays working.
Example(texture tile just defines number of repetitions required, value is 1 in this case):
glBegin(GL_QUADS);
glTexCoord2d(0.0, textureTile);
glVertex3d(gridRect.left(), gridRect.top(), 0.0);
glTexCoord2d(0.0, 0.0);
glVertex3d(gridRect.left(), gridRect.bottom(), 0.0);
glTexCoord2d(textureTile, 0.0);
glVertex3d(gridRect.right(), gridRect.bottom(), 0.0);
glTexCoord2d(textureTile, textureTile);
glVertex3d(gridRect.right(), gridRect.top(), 0.0);
glEnd();
That said, I was only successful in loading a texture from an image I made. Since the image is suppose to be calculated and painted during run time, I tried making an image from the data to load as a texture.
I used the Qt API functionality for achieving the same. I failed to recreate the same image. Might I be suggested a way to create a texture image from data owned.
Thanks

Answer 1

Sorry for the late answering(in case someone else wanted the answer).
I found the answer to be the use of QOpenGLFramebufferObject.
Final code looks something like:
glViewport(0, 0, VIEW_PORT_SIZE, VIEW_PORT_SIZE);
QOpenGLFramebufferObject fbObject(VIEW_PORT_SIZE, VIEW_PORT_SIZE);
fbObject.bind();
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
//Switch to Ortho Mode
glMatrixMode(GL_PROJECTION); // Select Projection
glPushMatrix(); // Push The Matrix
glLoadIdentity(); // Reset The Matrix
glOrtho(left, right, bottom, top, -100, 100); // Select Ortho Mode
glMatrixMode(GL_MODELVIEW); // Select Modelview Matrix
glPushMatrix(); // Push The Matrix
glLoadIdentity(); // Reset The Matrix
//Initialize variables
SPointData point1, point2, point3, point4;
//Paint on buffer
//.................<some painting task>................
//Switch to perspective mode
glMatrixMode(GL_PROJECTION); // Select Projection
glPopMatrix(); // Pop The Matrix
glMatrixMode(GL_MODELVIEW); // Select Modelview
glPopMatrix(); // Pop The Matrix
fbObject.release();
return fbObject.toImage();