I was asking the wrong question as it turns out. Building the vtk framework for iOS wasn’t really the issue; the problem is trying to compile the sample program VTKViewer which is included as an example program. And quite possibly VTK_OPENGL_USE_GLES=on is happening. Because like I said it’s not an issue with the framework: it is the sample programs which are hardcoded to use OpenGL2, I guess?
For example, in VTKViewer/VTKView.m, we see the line
#include “vtkRenderingOpenGL2ObjectFactory.h”
so it would seem this example program explicitly depends on OpenGL2 as oppposed to OPENGL_GLES.
Same for the VolumeRender example directory: in MyGLKViewController we see:
#include “vtk/vtkRenderingOpenGL2ObjectFactory.h”
It’s great that I can build the VTK framework for iOS; but without an example program (which I seriously doubt I would be able to write on my own), I can’t know that this really still working. Is there any updated iOS example programs somewhere someone could point me to?