🔒 Locked

Z-Buffer read error

Started by Grizwald Oct 3, 2002 at 9:51 PM 2 replies 500+ views

Original Post

Grizwald

Oct 3, 2002 at 9:51 PM

ok...i can''t get anything other than a one from my z-buffer. yes i''m clearing it. Yes i''m checking after i render

. z-buffer init code....

  
	glEnable(GL_DEPTH_TEST);
	glClearDepth(1.0f);															
	glDepthFunc(GL_LEQUAL);

read code...MouseX and MouseY are window coordinates...

  
	float MouseZ = 1;
	RECT r;
	GetWindowRect (Driver->hWnd ,&r);
	float MouseY2 = r.bottom - r.top - Driver.TitleSize - MouseY;

	glReadPixels (MouseX,MouseY2,1,1,GL_DEPTH_COMPONENT, GL_FLOAT, &MouseZ);

i can read color values fine, but z-buffer values don''t give me anything but a one. thanks for help

zedzeek

164

zedzeek

Oct 4, 2002 at 12:56 AM

float mouseX

check the spec i think those floats have to be ints.

anyways
>>float MouseY2 = r.bottom - r.top - Driver.TitleSize - MouseY;<<

i can see that easily going wrong

chuck this just before the read to see if that points actually on the screen
printf("%d\n", mouseY );

-------------

glClearDepth(0.445f);
try it now if it saiz 0.445 then its not seeing anything under the mouseX,mouseY position are u sure youve drawn something there

http://uk.geocities.com/sloppyturds/kea/kea.html
http://uk.geocities.com/sloppyturds/gotterdammerung.html

moore52

Oct 4, 2002 at 5:20 AM

Problem can be in creating gl window.

Make sure you use 32 and TWO buffers.
Dont know why but if you using triple buffering you SOMETIMES cannot use glReadPixels

ah and more:
glClearColor (or something like that)

Grizwald

Author

Grizwald

Oct 4, 2002 at 4:25 PM

my z-bits are 32, and i''m using double buffering, yes i am rendering before I test. It works with everything BUT DEPTH_COMPONENT (LUMINANCE, RED, BLUE etc...) but why not depth?!?!?! this is sooo frustrating. Everything i have coded until this has gone soo smoothly

Topic Locked

This topic has been locked by a moderator. New replies are not allowed.