Command Line Options

This article describes the existing command-line options supported by X-Plane; it is essentially an extract of X-Plane's command line help. You can find instructions on using command line options here.

Command Line Options exist to control program behavior beyond the default settings.
X-Plane can take a number of command-line flags, in the form of --flag or--flag=value. While OpenGL options are available for all X-Plane-related applications; the frame-rate test is only for X-Plane itself.

--help or -h Prints the message listing all command-line options, then quits.

Sound related Options
--no_sound Runs without initializing sound - can help identify a problem with sound hardware.

Options to Disable Video Hardware Acceleration
Normally X-Plane uses all available hardware capabilities to maximize the frame rate, these options force X-Plane not to use some aspects of hardware acceleration. This impacts frame rate, but can sometimes allow you to work around driver bugs.

--no_vbos Disable the use of vertex buffer objects, as defined by GL_ARB_vertex_buffer_object. VBOs are used to accelerate all aspects of X-Plane drawing.

--no_fbos Disable the use of framebuffer obects, even if the hardware supports them.

--no_pbos Disable the use of pixelbuffer obects, even if the hardware supports them.

--no_sprites Disables the use of point sprites, as defined by GL_ARB_point_sprite. Point sprites are used to accelerate runway lights, among other things.

--no_pixel_counters Disable pixel counters, as defined by GL_ARB_occlusion_query. Pixel counters are used to calculate sun glare, among other things.

--no_aniso_filtering Disable anisotropic filtering of textures, as defined by GL_EXT_texture_filter_anisotropic. Anisotropic filtering is used to make runways look better.

--no_hw_mipmap Disable hardware accelerated mipmap-creation, as defined by GL_SGIS_generate_mipmap. X-Plane will still use mipmapping, but it will create the mipmap images on the CPU instead of the GPU.

--no_fshaders Disable the use of fragment shaders, even on hardware that reports having them.

--no_vshaders Disable the use of vertex shaders, even on hardware that reports having them.

--no_glsl Disable the use of GLSL, even on hardware theat supports it.

--no_threaded_ogl Disable the use of OpenGL via multiple threads.

Options To Enable Incompatible Video Hardware Acceleration
X-Plane will in a few cases intentionally disable hardware acceleration to work around known driver compatibility bugs. You can force X-Plane to use the feature anyway (if the card supports it) with these options, but they may cause the sim to crash.

--use_vbos Forces the use of VBOs, even on drivers where we at one point found them to be unstable.

--use_sprites Forces the use of point sprites, even on drivers where they cause bugs.

--use_fshaders Force the use of fragment shaders, even if they would not normally be used.

--use_vshaders Force the use of vertex shaders, even if they would not be used.

--use_glsl Force the use of GLSL even on cards where we would avoid it due to driver compatibility problems.

--force_run X-Plane will not run on a machine that does not appear to have some minimum requirements, like at least two texture units. This will allow X-Plane to run no matter what the hardware looks like. Please note that most of the time if X-Plane out-right refuses to run, it will probably crash later if --force_run is used.

Frame Rate Options Logging
--fps_test=n This runs X-Plane in frame-rate test mode. The number indicates a frame rate test number, which is 3 digits indicating a combination of camera angle, scenery complexity, and weather settings. X-Plane will run for 90 seconds and quit, outputting 3 framerates to the Log.txt file for panel view, no-panel view, and paused no-panel view. This can be used to get repeatable performance measurements without changing preferences. (The preferences file is ignored when the framerate test is in effect.)

--require_fps=n When used after --fps_test this puts X-Plane into a pass-fail mode. The sim will run only one 30 second test with the flight model paused. The sim will then exit with 0 if the measured fps is higher than N or 1 if the fps is lower. This can be used to create a shell script that will automatically detect whether X-Plane performance is as expected.