I had this problem with the render 2 texture module the y-axis was always flipped in OpenGL.
Here is my solution which is part of the module, maybe it will help?:
Here is my solution which is part of the module, maybe it will help?:
Function ViewportSet(X:Int=0,Y:Int=0,Width:Int=640,Height:Int=480,FlipY:Byte=False) ?Win32 If DX TD3D7Max2DDriver(_max2dDriver).viewport.dwX=x TD3D7Max2DDriver(_max2dDriver).viewport.dwY=y TD3D7Max2DDriver(_max2dDriver).viewport.dwWidth=width TD3D7Max2DDriver(_max2dDriver).viewport.dwHeight=height PrimaryDevice.device.SetViewport(TD3D7Max2DDriver(_max2dDriver).viewport) Else ? If FlipY glViewport(X, Y, Width, Height) glMatrixMode(GL_PROJECTION) glPushMatrix() glLoadIdentity() gluOrtho2D(X, GraphicsWidth(), GraphicsHeight(),Y) glScalef(1, -1, 1) glTranslatef(0, -GraphicsHeight(), 0) glMatrixMode(GL_MODELVIEW) Else glViewport(X, Y, Width, Height) glMatrixMode(GL_PROJECTION) glLoadIdentity() glOrtho(X, GraphicsWidth(), GraphicsHeight(), Y, -1, 1) glMatrixMode(GL_MODELVIEW) glLoadIdentity() EndIf ?Win32 EndIf ? ' Print "tRender : ViewportSet OK" Return True EndFunction