OK thanks.
Just to let everyone know, I now have code in place that detects if the driver was changed (ini file setting altered) and the game crashed (due to there not being a "goodexit" file in the data folder) so that it can copy ini a default ini file with DirectX as the default driver. This works well on my crappy laptop. It bombs when you change to OpenGl mode on the options screen, then next time you try to load it, it works because it has reverted to DirectX.
It seems that when I try to do OpenGL full-screen on my game, setting the graphics contect succeeds and you even see the screen draw for like 1 frame and then it bombs, so it's not instant just after the setting is changed, it happens later when OpenGL fills up the VRAM. Shame that OpenGL is so unstable in this respect and can't generate some nice tracable error codes.
Just to let everyone know, I now have code in place that detects if the driver was changed (ini file setting altered) and the game crashed (due to there not being a "goodexit" file in the data folder) so that it can copy ini a default ini file with DirectX as the default driver. This works well on my crappy laptop. It bombs when you change to OpenGl mode on the options screen, then next time you try to load it, it works because it has reverted to DirectX.
It seems that when I try to do OpenGL full-screen on my game, setting the graphics contect succeeds and you even see the screen draw for like 1 frame and then it bombs, so it's not instant just after the setting is changed, it happens later when OpenGL fills up the VRAM. Shame that OpenGL is so unstable in this respect and can't generate some nice tracable error codes.