# SharpEmu: environment variables that are not on the GUI options pages ## Scope This list contains each `SHARPEMU_*` environment variable in the repository that the GUI does not show. The GUI shows 14 variables on its **Options** and **Game options** pages. This list does not contain them: `SHARPEMU_BTHID_UNAVAILABLE`, `SHARPEMU_CRASH_CAPTURE`, `SHARPEMU_DEFAULT_PROFILE`, `SHARPEMU_DISABLE_IMPORT_LOOP_GUARD`, `SHARPEMU_DUMP_SPIRV`, `SHARPEMU_LOG_DIRECT_MEMORY`, `SHARPEMU_LOG_IO`, `SHARPEMU_LOG_NP`, `SHARPEMU_PROFILE_PERFORMANCE`, `SHARPEMU_PROFILE_PERFORMANCE_FRAME_TRACE`, `SHARPEMU_RENDERDOC`, `SHARPEMU_VK_DISABLE_IMPLICITS`, `SHARPEMU_STRICT_COMPUTE`, `SHARPEMU_VK_VALIDATION`, `SHARPEMU_WRITABLE_APP0`. The list contains 252 variables. The source was examined on 2026-09-19, branch `dev`. The descriptions come from the code that reads each variable. The emulator was not started for this list. ## How to use a variable 1. Set the variable in the shell before you start the emulator or the GUI. 2. You can also enter additional env vars using the button next to the "Play" button from GUI. 3. The GUI also accepts a variable in the `EnvironmentToggles` list of its settings file. Write `NAME` or `NAME=value`. An entry without a value gets the value `1`. 4. The emulator reads most variables one time, when it starts. Start the game again after a change. 5. If the **Value** column shows `1`, only the value `1` turns the function on, unless the row gives other values. ## Number of variables in each group | Group | Variables | | --- | --- | | Behavior switches | 16 | | GPU and Vulkan | 50 | | Metal | 10 | | Audio and video | 7 | | Input | 5 | | Memory and CPU | 17 | | Loader | 11 | | Debugger | 1 | | Log channels | 72 | | Traces | 22 | | Data dumps | 12 | | Performance measurement | 16 | | Internal | 1 | | Tests and tools | 12 | ## Behavior switches These variables change how the emulator operates. | Variable | Value | Function | Code that reads it | | --- | --- | --- | --- | | `SHARPEMU_AGC_VERSION13_DEFAULTS` | text (`legacy`, `generic` or `0`) | Selects the register defaults for AGC version 13 requests. The default uses the version 11 compact tables. The values `legacy`, `generic` and `0` use the older generic layout. | `AgcExports.Init.cs` | | `SHARPEMU_DISABLE_LLE_LIBC` | `1` | Stops the use of the guest libc module for libc exports. The emulator then uses its HLE handlers for these exports. | `DirectExecutionBackend.cs` | | `SHARPEMU_HOLD_FIRST_FLIP_MS` | number | Stops the thread that submits the flip for this number of milliseconds on one guest flip. The range is 0 to 60000 and the default is 0 (off). `SHARPEMU_HOLD_FLIP_NUMBER` selects the flip. | `VideoOutExports.cs` | | `SHARPEMU_HOLD_FLIP_NUMBER` | number | Selects the guest flip that `SHARPEMU_HOLD_FIRST_FLIP_MS` holds. The minimum is 1 and the default is 1 (the first flip). | `VideoOutExports.cs` | | `SHARPEMU_IGNORE_GUEST_EXCEPTIONS` | `1` | `sceKernelRaiseException` returns OK and does not call the installed guest exception handler. Default is off. | `KernelExceptionCompatExports.cs` | | `SHARPEMU_IMPORT_LOOP_GUARD_SECONDS` | number | Sets the time that an import call pattern can repeat before the import loop guard forces a guest exit. The default is 5 seconds. The value 0 turns the guard off. | `DirectExecutionBackend.Imports.cs`, `DirectExecutionBackend.cs` | | `SHARPEMU_NET_REDIRECT` | IP address | Sends guest `connect` and `sendto` traffic to this host IP address. When unset, the emulator permits outbound guest traffic only to loopback addresses. If the value is not a valid IP address, the emulator keeps the original destination and permits the traffic. | `KernelSocketCompatExports.cs` | | `SHARPEMU_NO_FLIP_PACING` | `1` | Stops flip pacing. The emulator completes each flip immediately and does not wait for the display refresh time. The default is off. | `VideoOutExports.cs`, `VideoOutExports.FlipRequests.cs` | | `SHARPEMU_OVERLAY` | `0` | Hides the performance overlay at start, even when the video options have the overlay on. All other values use the video options. | `PerfOverlay.cs`, `PerformanceOverlayState.cs` | | `SHARPEMU_RETAIN_SUBMITTED_INDEX_DATA` | `0` | The default is on. The emulator keeps a copy of submitted index data until the translated draws run. Set to `0` to stop this copy. Use `0` only for a comparison test. | `AgcExports.SubmittedGeometry.cs` | | `SHARPEMU_RETAIN_SUBMITTED_VERTEX_DATA` | `0` | The default is on. The emulator keeps a copy of submitted vertex data until the translated draws run. Set to `0` to stop this copy. Use `0` only for a comparison test. | `AgcExports.SubmittedGeometry.cs` | | `SHARPEMU_SAVEDATA_DIR` | path | Set the root directory for save data. The default is `user/savedata` next to the executable. When this variable is set, the emulator does not move save data from the old layout. | `SaveDataStorage.cs`, `SaveDataExports.cs` | | `SHARPEMU_STALL_WATCHDOG_SECONDS` | number (seconds) | Sets the time without import progress before the stall watchdog operates. The default is 20. The watchdog writes a snapshot and stops the process with exit code 4. It does not operate when a guest thread is ready or a known wait is in progress. `0` stops the watchdog. | `DirectExecutionBackend.cs` | | `SHARPEMU_STRICT_RWLOCK_WRITER_PREFERENCE` | `1` | Set to `1` to make a guest thread take a free pthread rwlock as the exclusive writer. By default, the thread gets a compatibility writer record and the lock has no writer thread. | `KernelPthreadExtendedCompatExports.cs` | | `SHARPEMU_TEMP0_DIR` | path | Set the host directory for the guest `temp0` mount. The default is `user/temp//temp0` next to the executable. When unset, the kernel code sets this variable to the default path. | `AppContentExports.cs`, `KernelMemoryCompatExports.cs` | | `SHARPEMU_TRACE_TITLE_SHADER_STATE` | `1` | The SPIR-V translator changes the pixel shader at address 0x0000000500781200 for diagnosis. The first float output then shows the execution state, the wave mask state, and the export state as colors. Default is off. | `Gen5SpirvTranslator.cs` | ## GPU and Vulkan These variables change the GPU path or the Vulkan presenter. | Variable | Value | Function | Code that reads it | | --- | --- | --- | --- | | `SHARPEMU_CAPTURE_PIXEL_EXEC_PCS` | list (`pc:register` pairs) | At each given instruction PC, the pixel shader writes the execution flag to the given VGPR register. The value is 1.0 when the flag is set and 0.0 when it is not. `SHARPEMU_CAPTURE_PIXEL_VGPR_ADDRESS` must match the shader address. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_CAPTURE_PIXEL_IMAGE_ADDRESS` | hex address | Selects the pixel shader for the image capture by its program address. The default is no capture. Use it with `SHARPEMU_CAPTURE_PIXEL_IMAGE_PC`. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_CAPTURE_PIXEL_IMAGE_PC` | number (instruction PC) | Sets the image instruction whose result the SPIR-V translator copies to four VGPR registers. `SHARPEMU_CAPTURE_PIXEL_IMAGE_ADDRESS` must match the shader address. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_CAPTURE_PIXEL_IMAGE_VGPR_BASE` | number (0 to 252) | Sets the first VGPR register that receives the captured image components. The default is 248. Values above 252 use the default. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_CAPTURE_PIXEL_VGPR_ADDRESS` | hex address | Selects the pixel shader for the VGPR capture, execution capture and path marker functions by its program address. The default is no capture. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_CAPTURE_PIXEL_VGPR_DEST_BASE` | number (0 to 252) | Sets the first destination VGPR register for `SHARPEMU_CAPTURE_PIXEL_VGPR_SOURCES`. The default is 248. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_CAPTURE_PIXEL_VGPR_IGNORE_EXEC` | `1` | Makes the VGPR capture copies occur without the execution flag guard. The default applies the guard. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_CAPTURE_PIXEL_VGPR_PC` | number (instruction PC) | Sets the instruction PC at which the translator copies the source VGPR registers. `SHARPEMU_CAPTURE_PIXEL_VGPR_ADDRESS` must match the shader address. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_CAPTURE_PIXEL_VGPR_POINTS` | list (`pc:source:destination` triples) | At each given instruction PC, the pixel shader copies the source VGPR register to the destination register. Register numbers must be less than 256. `SHARPEMU_CAPTURE_PIXEL_VGPR_ADDRESS` must match the shader address. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_CAPTURE_PIXEL_VGPR_SOURCES` | list (one to four register numbers) | Gives the source VGPR registers that the translator copies at `SHARPEMU_CAPTURE_PIXEL_VGPR_PC`. The copies go to the registers that start at the destination base. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_DETILE` | `1` or `0` | Controls the detile step for tiled surfaces. The default detiles only the trusted swizzle modes. `1` also detiles the approximate modes and `0` uploads all surfaces as raw data. | `GnmTiling.cs` | | `SHARPEMU_DISABLE_FILL_CLEAR` | `1` | Stops the adaptation that treats a transparent premultiplied fill draw as a target overwrite. The default keeps the adaptation on. | `ShaderPipelineCache.Adaptations.cs` | | `SHARPEMU_ENABLE_CHUNKED_DRAWS` | `1` | The Vulkan presenter reads the value into a field. No code uses the field, so the variable has no effect. | `VulkanVideoPresenter.Draws.Recording.cs` | | `SHARPEMU_FORCE_ATTRIBUTE_FRAGMENT` | number (attribute location) | The Vulkan presenter reads the number into a field. No code uses the field, so the variable has no effect. | `VulkanVideoPresenter.Draws.Recording.cs` | | `SHARPEMU_FORCE_DEFAULT_RASTER_STATE` | `1` | The Vulkan presenter reads the value into a field. No code uses the field, so the variable has no effect. | `VulkanVideoPresenter.Draws.Recording.cs` | | `SHARPEMU_FORCE_FULLSCREEN_PIPELINE` | `1` | The Vulkan presenter reads the value into a field. No code uses the field, so the variable has no effect. | `VulkanVideoPresenter.Draws.Recording.cs` | | `SHARPEMU_FORCE_FULLSCREEN_VERTEX` | `1` | The Vulkan presenter reads the value into a field. No code uses the field, so the variable has no effect. | `VulkanVideoPresenter.Draws.Recording.cs` | | `SHARPEMU_FORCE_PACKED_EXPORT_ONE` | `1` | The SPIR-V translator replaces each packed half-float export component with the constant 1.0. This applies to all shaders. Default is off. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_PACKED_EXPORT_STORE_ONE` | `1` | The SPIR-V translator writes (1.0, 1.0) to the packed half-float pair before the export reads it. This applies only to the pixel shader at guest address 0x0000000500781200. Default is off. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_PACKED_STORE_EXEC_VALUES` | `1` | Each packed half-float store writes 1.0 when the EXEC mask is active and 0.5 when it is not. This shows the EXEC state as a color. This applies only to the pixel shader at guest address 0x0000000500781200. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_PIXEL_EXPORT_ADDRESS` | hex address | Sets the shader address filter for the pixel export debug overrides. The value is a hex address, and the `0x` prefix is optional. When unset, the overrides apply to all pixel shaders. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_PIXEL_EXPORT_PACK_VGPR_BASE` | number | Float pixel outputs read four vector registers that start at this base plus four times the export target. The translator packs the values to half-float and unpacks them again. The address filters select the shaders. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_PIXEL_EXPORT_VGPR_ADDRESS` | hex address | Sets the shader address filter for the two VGPR base overrides. The `0x` prefix is optional. When unset, the filter from `SHARPEMU_FORCE_PIXEL_EXPORT_ADDRESS` applies. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_PIXEL_EXPORT_VGPR_BASE` | number | Float pixel outputs read four vector registers that start at this base plus four times the export target. These values replace the decoded export sources. The address filters select the shaders. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_PIXEL_MAGENTA` | `1` | Each selected pixel shader export writes opaque magenta. The control flow, EXEC mask, geometry and raster state stay the same. Use `SHARPEMU_FORCE_PIXEL_EXPORT_ADDRESS` to select one shader. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_SOLID_FRAGMENT` | `1` | The Vulkan presenter reads the value into a field. No code uses the field, so the variable has no effect at this time. | `VulkanVideoPresenter.Draws.Recording.cs` | | `SHARPEMU_FORCE_TITLE_COMPARE_4D4` | `1` | The compare instruction at shader PC 0x4D4 always gives the result true. This applies only to the shader at guest address 0x0000000500781200. Default is off. | `Gen5SpirvTranslator.Alu.cs` | | `SHARPEMU_FORCE_TITLE_COMPARE_540` | `1` | The compare instruction at shader PC 0x540 always gives the result true. This applies only to the shader at guest address 0x0000000500781200. Default is off. | `Gen5SpirvTranslator.Alu.cs` | | `SHARPEMU_FORCE_TITLE_DEFAULT_RASTER_STATE` | `1` | The Vulkan presenter reads the value into a field. No code uses the field, so the variable has no effect at this time. | `VulkanVideoPresenter.Draws.Recording.cs` | | `SHARPEMU_FORCE_TITLE_EARLY_COLOR` | `1` | The pixel shader at guest address 0x0000000500781200 writes a constant to its first output and returns at once. A float output gets opaque magenta. An integer output gets zero. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_TITLE_EXPORT_EXEC` | `1` | The translator sets the EXEC mask to true and writes 1 to 64-bit register 126 before each pixel export store. This applies only to the pixel shader at guest address 0x0000000500781200. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_TITLE_FULLSCREEN_VERTEX` | `1` | The Vulkan presenter reads the value into a field. No code uses the field, so the variable has no effect at this time. | `VulkanVideoPresenter.Draws.Recording.cs` | | `SHARPEMU_FORCE_TITLE_SINGLE_MRT` | `1` | The translator declares only the first pixel output for the pixel shader at guest address 0x0000000500781200. It does not declare the other render target outputs. Default is off. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_FORCE_TITLE_SOLID_FRAGMENT` | `1` | The Vulkan presenter reads the value into a field. No code uses the field, so the variable has no effect at this time. | `VulkanVideoPresenter.Draws.Recording.cs` | | `SHARPEMU_FORCE_TITLE_VERTEX_OUTPUTS_ONE` | `1` | Vertex export targets 32 to 35 write the vector (1, 1, 1, 1). This applies only to the vertex shader at guest address 0x0000000500780000. Default is off. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_GPU_BACKEND` | `vulkan` or `metal` | Selects the guest GPU backend. The default is Vulkan. The value `metal` works only on macOS, and other hosts show a warning and use Vulkan. | `GuestGpu.cs` | | `SHARPEMU_GRAPHICS_SUBGROUPS` | `0` or `1` | Set `1` to use native Vulkan subgroup operations in graphics shaders. Set `0` to use the fallback path. When unset, the presenter uses them only if the subgroup size is 32 and the vertex and fragment stages support subgroups. | `VulkanVideoPresenter.cs`, `VulkanVideoPresenter.Device.Setup.cs` | | `SHARPEMU_MARK_PIXEL_PCS` | list of `pc:register` pairs | Makes the SPIR-V pixel shader write the float value 1.0 to a shader register when execution reaches the given instruction PC. Use decimal numbers, a register below 256, and a comma between pairs. It has an effect only for the shader address in `SHARPEMU_CAPTURE_PIXEL_VGPR_ADDRESS`. | `Gen5SpirvTranslator.cs` | | `SHARPEMU_MAX_GUEST_WORK_PER_RENDER` | number | Sets the maximum number of guest command stream slices that the Vulkan presenter runs in one render pass. The default is 1024, or 256 on macOS. The value must be more than 0. | `VulkanVideoPresenter.cs`, `VulkanVideoPresenter.CommandStream.cs` | | `SHARPEMU_RENDERDOC_CAPTURE_TIMEOUT_SECONDS` | number (seconds) | Set the maximum time for a RenderDoc frame capture. The emulator discards a capture that does not end in this time. The range is 1 to 120. The default is 15. | `RenderDocCapture.cs` | | `SHARPEMU_RENDERDOC_DLL` | path | Set the path of the RenderDoc library file. The emulator tries this path first. When unset or when the load fails, it searches the default library name and the known install paths. | `RenderDocCapture.cs` | | `SHARPEMU_RENDERDOC_WAIT` | number (seconds) or `enter` | Set to make the emulator wait before it starts Vulkan, so that you can attach RenderDoc. `enter` waits until you press Enter. A number waits that many seconds, from 1 to 300. Other text waits 15 seconds. | `VulkanVideoPresenter.Device.Setup.cs` | | `SHARPEMU_RENDER_WORK_BUDGET_MS` | number (milliseconds) | Set the maximum time that one render call uses for queued guest work in the Vulkan presenter. Work that remains stays in the queue for the next frame. `0` removes the limit. The default is 12 on macOS and 0 on other hosts. | `VulkanVideoPresenter.cs`, `VulkanVideoPresenter.RenderLoop.cs` | | `SHARPEMU_SHADER_MAX_STEPS` | number | Set the maximum number of dispatcher loop steps in each translated shader invocation. The limit makes sure that an incorrect loop stops. `0` removes the limit. The default is 100000. | `Gen5SpirvTranslator.cs`, `Gen5MslTranslator.cs` | | `SHARPEMU_SKIP_ALL_COMPUTE` | `1` | Set to `1` to make the Metal presenter skip all compute dispatches. The Vulkan presenter reads the value but does not use it. The default is off. | `MetalVideoPresenter.Compute.cs`, `VulkanVideoPresenter.cs` | | `SHARPEMU_SKIP_TALL_COMPUTE_Z` | number | Effect not clear from the code. The Vulkan presenter reads the number into a field for a minimum Z group count. No code uses that field. The default is 0. | `VulkanVideoPresenter.cs` | | `SHARPEMU_VK_DEBUG_LABELS` | `1` | Turns on Vulkan object names and command labels for capture tools. `SHARPEMU_VK_VALIDATION=1` also turns them on. Default is off because the labels add overhead to each draw. | `VulkanVideoPresenter.Draws.Recording.cs` | | `SHARPEMU_VK_DEVICE` | text (part of a device name) | Selects the Vulkan device whose name contains this text. The comparison ignores case. When unset, the presenter gives a score to each device and prefers a discrete GPU. | `VulkanVideoPresenter.Device.Setup.cs`, `VulkanVideoPresenter.cs` | | `SHARPEMU_VK_PIPELINE_CACHE_PATH` | path | Sets the path of the Vulkan pipeline cache file. The path can contain environment variables. Default is `user/pipeline_cache/