mesa/docs/drivers/freedreno
Danylo Piliaiev 229bd7b9b9 freedreno: Describe LRZ feedback mechanism
Some draws do write depth but cannot contribute to LRZ during the BINNING pass
e.g. when fragment shader has "discard" in it, however they can contribute to
LRZ during the RENDERING pass via LRZ feedback meachanism. This may allow the
draws that follow to depth test against the updated LRZ, this is especially
important if such "bad" draws were at the start of the renderpass.

LRZ feedback happens during the RENDERING pass when LRZ_FEEDBACK_ZMODE_MASK
is set, if draw has a6xx_ztest_mode that has corresponding flag set in
LRZ_FEEDBACK_ZMODE_MASK - its depth values would be used for feedback.

LRZ feedback alongside with LRZ testing also works during sysmem rendering.

Signed-off-by: Danylo Piliaiev <dpiliaiev@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25345>
2024-06-26 15:53:51 +00:00
..
hw freedreno: Describe LRZ feedback mechanism 2024-06-26 15:53:51 +00:00
ir3-notes.rst docs: use anonymous links when possible 2022-11-07 10:58:12 +00:00