Thanks again.
After some thought I figured maybe doing it on the GPU wasn't worth it - at least not without compute shaders. As you suggest you can do this calculation by rendering, but this is...

Thanks for the suggestion. My understanding is that these function determine the blending applied upon rendering. I would like to change the texture without rendering - because I am just changing a...

Hi,
I have a 3d texture of a dataset that the user can explore with arbitrarily positioned slice cuts in several viewports. I want to enable user drawing of regions of interest using a binary brush...

Thanks for reply.
Nothing would be written to the screen buffer when indxmode is false. The intention is to set indxmode to true only when there has been a spatial change in the scene and then only...

Hi,
Is it possible for a fragment shader to write out either a uint OR a vec4 all depending on the state of a uniform bool?
Assuming the appropriate FBO is attached once the drawing is started of...

Thanks!
That is good news.
Looking at my fifth edition superbible I think it boils down to me misunderstanding a sentence on frame buffer completeness and unsupported combinations of internal...

Hi,
I am displaying some slices of a 3d texture. In order to obtain the pixel coordinate in my original 3d image volume that is pointed to by the mouse i have used an offscreen render of an...

That works! Thanks so much - I skipped over glClearBuffer too fast.
Thanks again!

Soren

Thanks guys,
I have had a look at glClearBuffer but am unable to find a suitable example. Also the documentation does not specify integer use outside of depth and and stencil buffers.
Did not...

Hi,
I have trouble finding anything on how to clear an integer renderbuffer.
glClear(GL_COLOR_BUFFER_BIT) does set it to zero, but how can I set it to a different value?
Thanks,
Soren

sorry, that was QT speak.
initializeGL is the initialization function, I would assume analogous to glutInit
paintGL is analogous to the function passed to glutDisplayFunc.
So I guess the question...

Hi,
I have a scene that can be manipulated by user interaction. When there changes to the orientation, I draw the scene in an encoded fashion to an FBO, which works well.
I can't figure out how to...

Yes you are right - thank you.
Queried the channel and it is 8 bits which I guess I should have know since 24 bit color seems standard.
The problem arose as I rescaled a uint to float and then...

Hi,
what is the expected value - on screen - of this frag shader code (this is coloring a quad and I have deleted irrelevant lines):
"#version 150\n"
"out vec4 color;"
...