> For the complete documentation index, see [llms.txt](https://lfdocs.lookingglassfactory.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://lfdocs.lookingglassfactory.com/software/looking-glass-bridge-sdk/looking-glass-core-migration-guide.md). # Looking Glass Core Migration Guide [Looking Glass Core](/legacy/legacy-software/index.md) required the integrator to implement their own post-processing stage using a special shader and calibration parameters from the display. However, [Bridge](/software/looking-glass-bridge.md) takes care of this post-processing step by using a shared rendering context with a shared framebuffer object. An application using Bridge is then responsible for rendering views of 3D objects into a GPU texture using a [quilt format](/keyconcepts/quilts.md). Then the Bridge code will apply the Looking Glass optical transformation as a post-processing step. This process ensures that the application can render correctly to any Looking Glass display. The aforementioned integration pattern is very different from Looking Glass Core. So Bridge still supports the same functionality offered as part of Looking Glass Core using new native functions. The following table presents a mapping between Looking Glass Core functions and corresponding Bridge functions. {% hint style="info" %} Note: the shader used in legacy applications will need to be updated for applications that support Looking Glass displays released after 2022. {% endhint %} ## Looking Glass Core SDK → Bridge SDK | Looking Glass Core SDK | Looking Glass Bridge SDK | | ---------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------- | | [hpc\_InitializeApp](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/state-functions#hpc_initializeapp) | [initialize\_bridge](/software/looking-glass-bridge-sdk/native-function-reference.md#initialize_bridge) | | [hpc\_RefreshState](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/state-functions#hpc_refreshstate) | *No longer needed* | | [hpc\_CloseApp](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/state-functions#hpc_closeapp) | [uninitialize\_bridge](/software/looking-glass-bridge-sdk/native-function-reference.md#uninitialize_bridge) | | [hpc\_GetHoloPlayCoreVersion](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/state-functions#hpc_getholoplaycoreversion) | [get\_bridge\_version](/software/looking-glass-bridge-sdk/native-function-reference.md#get_bridge_version) | | [hpc\_GetStateAsJSON](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/general-query-functions#hpc_getstateasjson) | *No longer needed* | | [hpc\_GetHoloPlayServiceVersion](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/general-query-functions#hpc_getholoplayserviceversion) | [get\_bridge\_version](/software/looking-glass-bridge-sdk/native-function-reference.md#get_bridge_version) | | [hpc\_GetNumDevices](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/general-query-functions#hpc_getnumdevices) | *No longer needed* | | [hpc\_GetDeviceHDMIName](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/general-query-functions#hpc_getdevicehdminame) | [get\_device\_name](/software/looking-glass-bridge-sdk/native-function-reference.md#get_device_name) | | [hpc\_GetDeviceSerial](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/general-query-functions#hpc_getdeviceserial) | [get\_device\_serial](/software/looking-glass-bridge-sdk/native-function-reference.md#get_device_serial) | | [hpc\_GetDeviceType](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/general-query-functions#hpc_getdevicetype) | [get\_device\_type](/software/looking-glass-bridge-sdk/native-function-reference.md#get_device_type) | | [hpc\_GetDevicePropertyWinX](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertywinx) | [get\_window\_position](/software/looking-glass-bridge-sdk/native-function-reference.md#get_window_position) | | [hpc\_GetDevicePropertyWinY](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertywiny) | [get\_window\_position](/software/looking-glass-bridge-sdk/native-function-reference.md#get_window_position) | | [hpc\_GetDevicePropertyScreenW](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertyscreenw) | [get\_window\_dimensions](/software/looking-glass-bridge-sdk/native-function-reference.md#get_window_dimensions) | | [hpc\_GetDevicePropertyScreenH](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertyscreenh) | [get\_window\_dimensions](/software/looking-glass-bridge-sdk/native-function-reference.md#get_window_dimensions) | | [hpc\_GetDevicePropertyInvView](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertyinvview) | [get\_invview](/software/looking-glass-bridge-sdk/native-function-reference.md#get_invview) | | [hpc\_GetDevicePropertyRi](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertyri) | [get\_ri](/software/looking-glass-bridge-sdk/native-function-reference.md#get_ri) | | [hpc\_GetDevicePropertyBi](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertybi) | [get\_bi](/software/looking-glass-bridge-sdk/native-function-reference.md#get_bi) | | [hpc\_GetDevicePropertyPitch](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertypitch) | [get\_pitch](/software/looking-glass-bridge-sdk/native-function-reference.md#get_pitch) | | [hpc\_GetDevicePropertyCenter](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertycenter) | [get\_center](/software/looking-glass-bridge-sdk/native-function-reference.md#get_center) | | [hpc\_GetDevicePropertyTilt](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertytilt) | [get\_tilt](/software/looking-glass-bridge-sdk/native-function-reference.md#get_tilt) | | [hpc\_GetDevicePropertyDisplayAspect](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertyaspect) | [get\_displayaspect](/software/looking-glass-bridge-sdk/native-function-reference.md#get_displayaspect) | | [hpc\_GetDevicePropertyFringe](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertyfringe) | [get\_fringe](/software/looking-glass-bridge-sdk/native-function-reference.md#get_fringe) | | [hpc\_GetDevicePropertySubp](https://docs.lookingglassfactory.com/core/core-sdk/index-1/index/device-query-functions#hpc_getdevicepropertysubp) | [get\_subp](/software/looking-glass-bridge-sdk/native-function-reference.md#get_subp) | --- # Agent Instructions This documentation is published with GitBook. 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