X-Ray OpenGL shapes in Maya API

[Dilen Shah]

Hey guy,

I am creating a MPxLocatorNode and need it to be seen on top of all object in any viewport at all time.

How can I accomplish this?

D.

[Jack Straw]

As it is a full OpenGL viewport you can just use standard OpenGL methods for rendering on top. From a quick google it looks like glClear(GL_DEPTH_BUFFER_BIT) is the best option. I have done this before but I cannot remember the exact command I used that time.

Jack

[Janos Hunyadi]

You can even try glPolygonOffset. Not sure if it works inside maya, but in OpenGL that's the way to do it.

[Dilen Shah]

will try it out and let you know if i was successful.

D.

[Dilen Shah]

will try it out and let you know if i was successful.

D.

[Dilen Shah]

Hey Jack,

I am trying to use that but in python as I am using the OpenMayaRender module for it but glClear(GL_DEPTH_BUFFER_BIT) isnt in the attirbutes of it. Do you know which module is it from.

D.

[Jack Straw]

You need to call them from the OpenGL function table. Here is an example; http://www.fevrierdorian.com/blog/post/2010/02/12/Creating-custom-locator-with-Maya-s-Python-API 

[Dilen Shah]

I am calling them this is my test code:

import maya.OpenMayaRender as OpenMayaRender

view.beginGL()

# Pushed current state

glFT.glPushAttrib(OpenMayaRender.MGL_CURRENT_BIT)

# Enabled Blend mode (to enable transparency)

glFT.glEnable(OpenMayaRender.MGL_BLEND)

glFT.glClear(OpenMayaRender.GL_DEPTH_BUFFER_BIT) here is get the error OpenMayaRender doesnt have attribute

D.

[Jack Straw]

"The naming convention used in this file is to take the regular GL* definitions and add a "M" prefix." - Maya Python API Docs

Try OpenMayaRender.MGL_DEPTH_BUFFER_BIT.

[Dilen Shah]

you are the man! it worked had to do some changes here and there but got it working.

thnx!

[Dilen Shah]

Also found another way of doing this.

glFT.glDisable( OpenMayaRender.MGL_DEPTH_TEST )

...

...

your code and your opengl shape

glFT.glEnable( OpenMayaRender.MGL_DEPTH_TEST )

So two ways of doing this, this one makes to stop it after drawing, so might be better but i am nt sure.

D.