libretro.h: add a sensor sub-device index for composite controllers - #19453
Open
XenuIsWatching wants to merge 1 commit into
Open
libretro.h: add a sensor sub-device index for composite controllers#19453XenuIsWatching wants to merge 1 commit into
XenuIsWatching wants to merge 1 commit into
Conversation
Some controllers carry more than one sensor of the same kind on a single port. A Wii Remote with a Nunchuk attached is one player with two accelerometers, and adding MotionPlus makes it two accelerometers and a gyroscope, but retro_sensor_interface addresses exactly one sensor of each kind per port. A second port is not an alternative, because ports denote players. Carry a sub-device index in the upper bits of the existing ID, the same way RETRO_DEVICE_SUBCLASS encodes a subclass into a device ID. Index 0 denotes the controller itself and encodes to exactly the values already in use, so every existing core and frontend is unaffected. No new environment call or capability flag is needed, because the existing contract already describes the fallback: a frontend that does not implement this returns false from retro_set_sensor_state_t and 0 from retro_sensor_get_input_t, both of which are already documented, and a core that receives either answer behaves as it does today. Cores and frontends can therefore adopt this independently of one another. Definitions only; no behaviour changes.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Some controllers carry more than one sensor of the same kind on a single port. A Wii Remote with a Nunchuk attached is one player with two accelerometers, and adding MotionPlus makes it two accelerometers and a gyroscope, but retro_sensor_interface addresses exactly one sensor of each kind per port. A second port is not an alternative, because ports denote players.
Carry a sub-device index in the upper bits of the existing ID, the same way RETRO_DEVICE_SUBCLASS encodes a subclass into a device ID. Index 0 denotes the controller itself and encodes to exactly the values already in use, so every existing core and frontend is unaffected.
No new environment call or capability flag is needed, because the existing contract already describes the fallback: a frontend that does not implement this returns false from retro_set_sensor_state_t and 0 from retro_sensor_get_input_t, both of which are already documented, and a core that receives either answer behaves as it does today. Cores and frontends can therefore adopt this independently of one another.