Color Picker / Choser for an OpenGL Application

Question

I am building an OpenGL application. I read through the GLUI tutorial on Code Project to create windows form controls on an OpenGL Application. But my requirement is to develop a color choser/picker, like an RGB chart or RGB cube to select a color. The tutorial on Code project shows the list of colors as a drop down box. However that wont really help me, as I require it to be present as a windows color picker. I know that color picker as a dialog box is a part of the windows application. Can anyone suggest me a way to use it with my OpenGL Application?

score 2 · Answer 1 · answered Dec 19 '14 at 05:06

2

On windows, you can call directly ChooseColor() from the windows API. It will open the native color color chooser.If you need a cross-platform solution, tiny file dialogs on sourceforge also has a color picker and no main loop.

answered Dec 19 '14 at 05:06

alMation3

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score 2 · Answer 2 · answered Mar 25 '12 at 16:38

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You can try fox-toolkit. It is a C++ based Toolkit for developing Graphical User Interfaces. It provides Color Picker and OpenGL widgets for 3D graphical manipulations.

answered Mar 25 '12 at 16:38

CsaByte

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score 1 · Accepted Answer · answered Mar 26 '12 at 09:50

You could render a Quad/Triangle/Cirle with different color on each vertex
and activate smooth shading for interpolation between these points.

Then just read back the color value from OpenGL at the mouse position.

edit: or like that where you calculate the color on the mouse position by yourself (reading values slows down OpenGL a lot!): http://sharathpatali.wordpress.com/2009/07/07/a-color-picker-for-pymt/

score 1 · Answer 4 · answered Mar 26 '12 at 12:20

I did this with simple gradient image which i kept in memory. Then i just tracked my mouse position on the image, and simply read the data from the image (that was kept in RAM) and get the 32bit RGBA color value for it. This is easier than reading the pixels from screen (also faster and more reliable).

This also allows a lot more flexible way of presenting the palette, only your imagination is the limit on the looks of your palette. Note: you must use 32bit colors on the image, because if you want smooth edges, you simply just fade the alpha but keep the colors the same, so the colors wont get distorted at edges. Don't forget to enable blending when rendering the image.

Color Picker / Choser for an OpenGL Application

4 Answers4