about glReadPixels

OpenGL OpenGL: Basic Coding
1

I have used glReadPixels to get the z-value of the pixel , but when I use gluUnProject and draw the pixel dot ,the point is not correctly, why ?

2

Dear xiaomi,

Did you properly Defined Depth characteristics

  1. glEnable( GL_DEPTH_TEST );
  2. glClearDepth( 1.0 );

Rajesh.R
IRIS, CAIR,
Bangalore

3

Dear iris_raj :
thanks , and the Depth characteristics has been defined , some of the result is right ,but some is correctly.