(visuOgre): using of a non initialized variable for color computation in GLSL
Summary
PointList where drawn black on macOS in OgreViewer, due to wrong GLSL code, introduced in MR https://git.ircad.fr/Sight/sight/merge_requests/195
Steps to reproduce
Open OgreViewer, load a mesh, draw some landmarks, they should be red on all platforms. To be sure, modify the XML and change the color. The changed color must match what you see.