You're probably using one of the other renderers.  Make sure to enable the grid leaper in the settings first.

There's a bug in the last release where you need to enable 'experimental settings' and then restart before it'll even display the option for that renderer.  IIRC it's fixed in master.

-tom

On June 25, 2016 1:30:04 PM PDT, Aashay Mittal < > wrote:
>hi,
>thanks for the reply.
>I saw the other similar discussion as well and hence, looked into
>the "GLGridLeaper-Method-2D-L.glsl" and other "GLGridLeaper*" files.
>All of
>these contain a function, *ComputeColorFromVolume( )* that *returns a
>vec4
>containing the RGBA values*, to "GLGridLeaper-blend.glsl".
>However, i tried to tweak the same by supplying a vec4(0,0,0,0) to all
>and
>check if this function is actually being called, but no visible changes
>appear.
>Also, commands like printf( ),cout do not seem to work, indicating
>these
>files are not being accessed.
>
>
>
>*RegardsAashay Mittal*
>2014001
>Non-Tech Events OC | Esya'16
>
>On Sun, Jun 26, 2016 at 1:03 AM, tom (mobile) < >
>wrote:
>
>> Hi, welcome.
>>
>> Timely.  Someone else asked about the exact same thing ~a month ago.
>> Check the archives for details, but basically: this happens in glsl
>> shaders, I would recommend the GLGridLeaper* ones since that renderer
>is
>> the best one.  But, as far as I'm aware that still requires you have
>a
>> newish NVIDIA card and Linux/Windows, still.
>>
>> HTH,
>>
>> -tom
>>
>> On June 25, 2016 10:50:01 AM PDT, Aashay Mittal
>< >
>> wrote:
>> >Hi
>> >I am a student at IIIT Delhi (India), and am working on a project on
>> >transfer
>> >functions.
>> >ImageVis3D seems to be the best software that is open-source and
>> >supports the
>> >gradient based 2D transfer function.
>> >I however, want to modify the transfer function applied to apply
>> >transfer
>> >function based on their 3D spatial location.
>> >(i.e. i want to assign a voxel denoted by P(x,y,z) an RGBA mapping
>> >instead of
>> >a point indicated by (I,f'(I) ).
>> >I've been looking into the software from quite a few days, but since
>am
>> >a
>> >student and new to graphics and rendering, haven't been able to have
>> >much
>> >success in the same.
>> >So if you could please point out the files where this mapping
>between
>> >points
>> >and color assigned to them is taking place.
>> >
>> >Regards
>>
>>