Where is mystake ?

I used following function from nehe.gamedev.net , but it doesn’t work, i drawed to scene one white quad, and it returned no hits, actually for this code it just closed form. Can you please tell my where could a mystake ?

void Selection(void) // This is where selection is done
GLuint buffer[512]; // Set up a selection buffer
GLint hits; // The number of objects that we selected

if (game)		// Is game over?
	return;		// If so, don't bother checking for hits

PlaySound("data/shot.wav",NULL,SND_ASYNC);	// Play gun shot sound

// The size of the viewport. [0] is <x>, [1] is <y>, [2] is <length>, [3] is <width>
GLint	viewport[4];

// This sets the array <viewport> to the size and location of the screen relative to the window
glGetIntegerv(GL_VIEWPORT, viewport);
glSelectBuffer(512, buffer);		// Tell OpenGL to use our array for selection

// Puts OpenGL in selection mode. Nothing will be drawn. Object ID's and extents are stored in the buffer.
(void) glRenderMode(GL_SELECT);

glInitNames();			// Initializes the name stack
glPushName(0);			// Push 0 (At least one entry) onto the stack

glMatrixMode(GL_PROJECTION);	// Selects the projection matrix
glPushMatrix();			// Push the projection matrix
glLoadIdentity();		// Resets the matrix

// This creates a matrix that will zoom up to a small portion of the screen, where the mouse is.
gluPickMatrix((GLdouble) mouse_x, (GLdouble) (viewport[3]-mouse_y), 1.0f, 1.0f, viewport);

// Apply the perspective matrix
gluPerspective(45.0f, (GLfloat) (viewport[2]-viewport[0])/(GLfloat) (viewport[3]-viewport[1]), 0.1f, 100.0f);
glMatrixMode(GL_MODELVIEW);		// Select the modelview matrix
DrawTargets();				// Render the targets to the selection buffer
glMatrixMode(GL_PROJECTION);		// Select the projection matrix
glPopMatrix();				// Pop the projection matrix
glMatrixMode(GL_MODELVIEW);		// Select the modelview matrix
hits=glRenderMode(GL_RENDER);		// Switch to render mode, find out how many
					// Objects were drawn where the mouse was
if (hits > 0)				// If there were more than 0 hits
	int	choose = buffer[3];	// Make our selection the first object
	int depth = buffer[1];		// Store how far away it is

	for (int loop = 1; loop < hits; loop++)		// Loop through all the detected hits
		// If this object is closer to us than the one we have selected
		if (buffer[loop*4+1] < GLuint(depth))
			choose = buffer[loop*4+3];	// Select the closer object
			depth = buffer[loop*4+1];	// Store how far away it is

	if (!object[choose].hit)		// If the object hasn't already been hit
		object[choose].hit=TRUE;	// Mark the object as bening hit
		score+=1;			// Increase score
		kills+=1;			// Increase level kills
		if (kills>level*5)		// New level yet?
			miss=0;			// Misses reset back to zero
			kills=0;		// Reset level kills
			level+=1;		// Increase level
			if (level>30)		// Higher than 30?
				level=30;	// Set level to 30 (Are you a god?)