Visualization
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How to get proper colour in OpenGL?

Jere
Expert
See attached image. The preview looks correct in Internal Engine and LightWorks, but how do I get the siding colour to be correct in the openGL window? The siding appears correct, except the siding appears to be white.

Surface_GL.PNG
ArchiCAD 26; Windows 11; Intel i7-10700KF; 64GB RAM, GeForce GTX 3060
3 REPLIES 3
Anonymous
Not applicable
The problem is that the material is using an alpha channel mask in IE and LW over a background color that you can change without changing the texture.

The OpenGL engine does not support this so the background of the alpha channel is rendered as white. The only fix is to make a texture with the color you want and replace the current alpha mask texture. This will then be used in both OpenGL and the Internal Engine. The LightWorks engine can be matched to this or stay as is.

I developed a set of materials for a client to deal with this problem. There is no easy solution but a good trick is to set up a Photoshop file with one layer for the alpha channel mask and layers of solid color (or textured as desired) behind that can be turned on and off to save as PNG textures to make OpenGL friendly, color specific materials.
Jere
Expert
Thanks Matthew. I'll have to see if I can figure it out. I'm new to rendering and image manipulation.
ArchiCAD 26; Windows 11; Intel i7-10700KF; 64GB RAM, GeForce GTX 3060
Anonymous
Not applicable
This is also always a desire for me. Each time I have ventured in to Photoshop (Actually I only even own an old version of Elements) I am confused. I do pretty good with math, but can never get the logic of the Photoshop processes.