From: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Date: Tue, 5 Mar 2019 17:17:13 +0000 (+0100)
Subject: radv: fix color conversions for normalized uint/sint formats
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=e03e7c510f571a8867ab7a8604058c075c601a70;p=mesa.git

radv: fix color conversions for normalized uint/sint formats

The hardware actually rounds before conversion. This now matches
what values are used when performing fast clears vs slow clears.

This fixes a rendering issue with Far Cry 3&4. This also fixes
a bunch of CTS tests that use a 8-bit UNORM format (only when
the 512*512 image size hint is manually disabled).

Cc: "19.0" "19.1" <mesa-stable@lists.freedesktop.org>
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
---

diff --git a/src/amd/vulkan/radv_formats.c b/src/amd/vulkan/radv_formats.c
index bee1c57e610..5af172c8e7f 100644
--- a/src/amd/vulkan/radv_formats.c
+++ b/src/amd/vulkan/radv_formats.c
@@ -1032,10 +1032,22 @@ bool radv_format_pack_clear_color(VkFormat format,
 				assert(channel->size == 8);
 
 				v = util_format_linear_float_to_srgb_8unorm(value->float32[c]);
-			} else if (channel->type == VK_FORMAT_TYPE_UNSIGNED) {
-				v = MAX2(MIN2(value->float32[c], 1.0f), 0.0f) * ((1ULL << channel->size) - 1);
-			} else  {
-				v = MAX2(MIN2(value->float32[c], 1.0f), -1.0f) * ((1ULL << (channel->size - 1)) - 1);
+			} else {
+				float f = MIN2(value->float32[c], 1.0f);
+
+				if (channel->type == VK_FORMAT_TYPE_UNSIGNED) {
+					f = MAX2(f, 0.0f) * ((1ULL << channel->size) - 1);
+				} else {
+					f = MAX2(f, -1.0f) * ((1ULL << (channel->size - 1)) - 1);
+				}
+
+				/* The hardware rounds before conversion. */
+				if (f > 0)
+					f += 0.5f;
+				else
+					f -= 0.5f;
+
+				v = (uint64_t)f;
 			}
 		} else if (channel->type == VK_FORMAT_TYPE_FLOAT) {
 			if (channel->size == 32) {