lima: fix handling of reverse depth range
Looks like we need to handle cases when near > far and near == far.
In first case we just need to swap near and far, and in second we
need subtract epsilon from near if it's not zero.
Fixes 10 tests in dEQP-GLES2.functional.depth_range.*
Reviewed-by: Qiang Yu <yuq825@gmail.com>
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3400>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3400>
diff --git a/src/gallium/drivers/lima/lima_draw.c b/src/gallium/drivers/lima/lima_draw.c
index af50996..088f33e 100644
--- a/src/gallium/drivers/lima/lima_draw.c
+++ b/src/gallium/drivers/lima/lima_draw.c
@@ -1090,9 +1090,17 @@
struct pipe_depth_state *depth = &ctx->zsa->base.depth;
render->depth_test = lima_calculate_depth_test(depth, rst);
+ ushort far, near;
+
+ near = float_to_ushort(ctx->viewport.near);
+ far = float_to_ushort(ctx->viewport.far);
+
+ /* Subtract epsilon from 'near' if far == near. Make sure we don't get overflow */
+ if ((far == near) && (near != 0))
+ near--;
+
/* overlap with plbu? any place can remove one? */
- render->depth_range = float_to_ushort(ctx->viewport.near) |
- (float_to_ushort(ctx->viewport.far) << 16);
+ render->depth_range = near | (far << 16);
struct pipe_stencil_state *stencil = ctx->zsa->base.stencil;
struct pipe_stencil_ref *ref = &ctx->stencil_ref;
diff --git a/src/gallium/drivers/lima/lima_state.c b/src/gallium/drivers/lima/lima_state.c
index 286529e9d..cd910fb 100644
--- a/src/gallium/drivers/lima/lima_state.c
+++ b/src/gallium/drivers/lima/lima_state.c
@@ -248,8 +248,12 @@
ctx->viewport.top = viewport->translate[1] + fabsf(viewport->scale[1]);
/* reverse calculate the parameter of glDepthRange */
- ctx->viewport.near = viewport->translate[2] - viewport->scale[2];
- ctx->viewport.far = viewport->translate[2] + viewport->scale[2];
+ float near, far;
+ near = viewport->translate[2] - viewport->scale[2];
+ far = viewport->translate[2] + viewport->scale[2];
+
+ ctx->viewport.near = MIN2(near, far);
+ ctx->viewport.far = MAX2(near, far);
ctx->viewport.transform = *viewport;
ctx->dirty |= LIMA_CONTEXT_DIRTY_VIEWPORT;