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OpenGL_Guru

OpenGL OpenGL picking in 2D and 3D at the same time..

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DISCLAIMER -- i could explain my problem a lot better if someone might be so kind to PM me with their email address so i could send them a sample image of what i am trying to do. this will help everyone see clearly what i am talking about. thanks! problem is is that i am rendering a world in 3D, colored by a min and a max value through a 1D texture lookup. i have a 2D legend that corresponds to the coloring scheme with some slider bars on both ends of the legend. as of now i am using a picking scheme to retrieve the 3D (x, y, z) and i draw a glut sphere at that spot to show that the function is successful and it is. i also have a GUI class -- which tells main everything about the GUI as well as returns to main certain callbacks such as a screen(x, y)(from passivemotion) for the picking that i described above but for also a menu. what i want to do is be able to manipulate the slider bars on the 2D legend.. that is move them up and down across the 2D legend without interfering with manipulating the 3D world. i am using glutMotionFunc() to rotate the 3D world with the mouse(just a basic mouse function). i am also using glutPassiveMotionFunc() for the callback in main program for the onscreen menu that i mentioned. i simply return the x,y coordinate of the mouse real time using passivemotion. if button_down == true, then i activate the callback and if the x,y matches one the menus located on the screen -- then i do something. so back to my original problem -- i want to be able to manipulate the 2D legend without interfering with the other mouse functions. anyone have any suggestions or ideas? again if i could have an image on here it would make things much easier to explain. thanks in advance!!

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Ok my interpretation of the question:

You have multiple GUI elements, each one has separate mouse pointer data.
You want to be able to manipulate one of your GUI controls, without affecting the settings on the other.
Each responds to mouse motion and clicks, so the current problem is that manipulations to one messes up the settings on the other.

How about detect where the mouse is at the moment, and if its above one of your controls, disable changes to the other guy?
Details left as an exercise....

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