[Mesa-dev] [PATCH v2 11/14] i965: Support sampling with hiz during rendering

[Jordan Justen]

For gen8, we can sample from depth while using the hiz buffer. This
allows us to sample depth without resolving from hiz to the depth
texture.

To do this we must resolve to hiz before drawing so we can use the hiz
buffer to sample while rendering. Hopefully the hiz buffer will
already be resolved in most cases because it was previously rendered,
meaning the hiz resolve is a no-op.

Note that this is still controlled by the
intel_miptree_sample_with_hiz function, and we will enable hiz
sampling for gen8 in a separate patch.

Signed-off-by: Jordan Justen <jordan.l.justen at intel.com>
Reviewed-by: Topi Pohjolainen <topi.pohjolainen at intel.com>
---
 src/mesa/drivers/dri/i965/brw_draw.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/mesa/drivers/dri/i965/brw_draw.c b/src/mesa/drivers/dri/i965/brw_draw.c
index ac21656..3c63b8a 100644
--- a/src/mesa/drivers/dri/i965/brw_draw.c
+++ b/src/mesa/drivers/dri/i965/brw_draw.c
@@ -321,7 +321,10 @@ brw_predraw_resolve_buffers(struct brw_context *brw)
       tex_obj = intel_texture_object(ctx->Texture.Unit[i]._Current);
       if (!tex_obj || !tex_obj->mt)
 	 continue;
-      intel_miptree_all_slices_resolve_depth(brw, tex_obj->mt);
+      if (intel_miptree_sample_with_hiz(brw, tex_obj->mt))
+         intel_miptree_all_slices_resolve_hiz(brw, tex_obj->mt);
+      else
+         intel_miptree_all_slices_resolve_depth(brw, tex_obj->mt);
       intel_miptree_resolve_color(brw, tex_obj->mt);
       brw_render_cache_set_check_flush(brw, tex_obj->mt->bo);
    }
-- 
2.0.1