[Mesa-dev] [PATCH] nv50, nvc0: fix depth range when halfz is enabled

[Ilia Mirkin]

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97231
Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
Cc: "11.2 12.0" <mesa-stable at lists.freedesktop.org>
---
 src/gallium/drivers/nouveau/nv50/nv50_state_validate.c | 18 ++++++++++++++----
 src/gallium/drivers/nouveau/nvc0/nvc0_state_validate.c | 18 ++++++++++++++----
 2 files changed, 28 insertions(+), 8 deletions(-)

diff --git a/src/gallium/drivers/nouveau/nv50/nv50_state_validate.c b/src/gallium/drivers/nouveau/nv50/nv50_state_validate.c
index 19181a9..1dd3647 100644
--- a/src/gallium/drivers/nouveau/nv50/nv50_state_validate.c
+++ b/src/gallium/drivers/nouveau/nv50/nv50_state_validate.c
@@ -265,13 +265,23 @@ nv50_validate_viewport(struct nv50_context *nv50)
       PUSH_DATAf(push, vpt->scale[1]);
       PUSH_DATAf(push, vpt->scale[2]);
 
-      zmin = vpt->translate[2] - fabsf(vpt->scale[2]);
-      zmax = vpt->translate[2] + fabsf(vpt->scale[2]);
+      /* If the halfz setting ever changes, the viewports will also get
+       * updated. The rast will get updated before the validate function has a
+       * chance to hit, so we can just use it directly without an atom
+       * dependency.
+       */
+      if (nv50->rast->pipe.clip_halfz) {
+         zmin = vpt->translate[2];
+         zmax = vpt->translate[2] + vpt->scale[2];
+      } else {
+         zmin = vpt->translate[2] - vpt->scale[2];
+         zmax = vpt->translate[2] + vpt->scale[2];
+      }
 
 #ifdef NV50_SCISSORS_CLIPPING
       BEGIN_NV04(push, NV50_3D(DEPTH_RANGE_NEAR(i)), 2);
-      PUSH_DATAf(push, zmin);
-      PUSH_DATAf(push, zmax);
+      PUSH_DATAf(push, zmin < zmax ? zmin : zmax);
+      PUSH_DATAf(push, zmin < zmax ? zmax : zmin);
 #endif
    }
 
diff --git a/src/gallium/drivers/nouveau/nvc0/nvc0_state_validate.c b/src/gallium/drivers/nouveau/nvc0/nvc0_state_validate.c
index 160abae..3791c27 100644
--- a/src/gallium/drivers/nouveau/nvc0/nvc0_state_validate.c
+++ b/src/gallium/drivers/nouveau/nvc0/nvc0_state_validate.c
@@ -329,12 +329,22 @@ nvc0_validate_viewport(struct nvc0_context *nvc0)
       PUSH_DATA (push, (w << 16) | x);
       PUSH_DATA (push, (h << 16) | y);
 
-      zmin = vp->translate[2] - fabsf(vp->scale[2]);
-      zmax = vp->translate[2] + fabsf(vp->scale[2]);
+      /* If the halfz setting ever changes, the viewports will also get
+       * updated. The rast will get updated before the validate function has a
+       * chance to hit, so we can just use it directly without an atom
+       * dependency.
+       */
+      if (nvc0->rast->pipe.clip_halfz) {
+         zmin = vp->translate[2];
+         zmax = vp->translate[2] + vp->scale[2];
+      } else {
+         zmin = vp->translate[2] - vp->scale[2];
+         zmax = vp->translate[2] + vp->scale[2];
+      }
 
       BEGIN_NVC0(push, NVC0_3D(DEPTH_RANGE_NEAR(i)), 2);
-      PUSH_DATAf(push, zmin);
-      PUSH_DATAf(push, zmax);
+      PUSH_DATAf(push, zmin < zmax ? zmin : zmax);
+      PUSH_DATAf(push, zmin < zmax ? zmax : zmin);
    }
    nvc0->viewports_dirty = 0;
 }
-- 
2.7.3