- Qt 5.15
- Qt Quick 3D
- Qt Quick 3D Environment Variables
- Qt Quick 3D | Commercial or GPLv3

# Qt Quick 3D Environment Variables

This page contains a list of all environment variables that Qt Quick 3D supports. The environment variables are primarily meant for testing, but they can also be used to set certain platform specific values.

Variable | Description
--- | ---
`QT_QUICK3D_DUMP_PERFTIMERS` | Dumps perf timers. This variable can be used to dump the performance timers with non-zero value.
`QT_QUICK3D_DUMP_RENDERTIMES` | Dumps render times. This variable can be used to dump the render times with non-zero value.

`QT_QUICK3D_FORCE_OPENGL_BACKEND`

Forces specific OpenGL backend. This integer value can be used to force the use of specific OpenGL backend provided it is supported.

- For OpenGL ES2 set the value to `1`.
- For OpenGL 3.x set the value to `2`.
- For OpenGL 4.x set the value to `3`.

`QT_QUICK3D_DUMP_SHADERS` | Dump generated shaders. This value can be used to dump the generated shader code for vertex- and fragment shaders with non-zero value.
`QT_QUICK3D_THREAD_COUNT` | Specifies the amount of thread used by the backend for background processing. This value can be used to set the amount of threads used by the backend for background processing.
`QT_QUICK3D_SHADER_PRECISION` | Specifies default shader precision. This value can be used to control the precision of generated shaders. Possible values are `lowp`, `mediump` and `highp`.
`QT_QUICK3D_SAMPLER_PRECISION` | Specifies default shader sampler precision. This value can be used to control the precision of samplers in generated shaders. Possible values are `lowp`, `mediump` and `highp`.