OpenGL / Dolphin System
The 'OpenGL / Dolphin System' references the leftover .exe file left in all retail Gamecube Pikmin 1 discs.
The name comes from when you open the .exe in the command prompt with the command "sysBootup.exe +output". This will create a UI for you that you can run different 'modules' from. The name of the window thats created is called 'OpenGL / Dolphin system'. The reason for this is that the developers of Pikmin 1 made the game side-by-side with windows programs for debugging and testing all of the formats and the game itself.
Theories
The file-formats and other peculiarities of Pikmin 1 leads us to a conclusion that the developers of the game used a very very old form of the J3D toolchain. A code library used to create Super Mario Sunshine and Pikmin 2. Could the 'OpenGL / Dolphin System' be an old version of the toolkit tailored towards Pikmin 1?