macOS Shader or Texture implementation in Mac vs Windows

[kacharo]

So, my application is to volume render a gray-scale 3D image.
It does this by 3D texturing and uses GLSL to display the values in the texture after clamping the values in data to [0,1]. The problem is, that during rendering, when I try to rotate the volume, there are a bunch of values that are wrongly clamped to either 0 or 1, that is, some data from the image is wrongly displayed.

The same code runs perfectly well on a Windows machine. Is there some difference in the way textures are accessed or clamps are implemented in opengl for windows and mac? Why is there this difference? I have opengl 2.1 on my Mac, and 2.2 on the windows machine if that is of any help.

Thanks

 

[Cromulent]

So, my application is to volume render a gray-scale 3D image.
It does this by 3D texturing and uses GLSL to display the values in the texture after clamping the values in data to [0,1]. The problem is, that during rendering, when I try to rotate the volume, there are a bunch of values that are wrongly clamped to either 0 or 1, that is, some data from the image is wrongly displayed.

The same code runs perfectly well on a Windows machine. Is there some difference in the way textures are accessed or clamps are implemented in opengl for windows and mac? Why is there this difference? I have opengl 2.1 on my Mac, and 2.2 on the windows machine if that is of any help.

Thanks

There is no OpenGL 2.2. Are you sure you don't mean OpenGL 3.2? If so there are some compatibility issues between the two. OpenGL 3+ is a bit of a change for the API.

 

[kacharo]

Well... actually the Opengl version on my windows machine is 2.1.2 precisely and on Mac it is 2.1 Nvidia 16.6. Is there API change in those too??

 

[Cromulent]

Well... actually the Opengl version on my windows machine is 2.1.2 precisely and on Mac it is 2.1 Nvidia 16.6. Is there API change in those too??

No they are the same version.

Hard to answer the question really without more information.