From da69cfd6685f9d564247ca259be0cc92b043417a Mon Sep 17 00:00:00 2001
From: Michael Parkin-White <mparkinwhite@apple.com>
Date: Tue, 11 Apr 2023 13:37:24 +0100
Subject: [PATCH] Metal: Add textureGrad support.

Authored by Apple: Michael Parkin-White
---
 .../gpu/shaders/metal/mtl_shader_defines.msl  | 34 +++++++++++++++++--
 1 file changed, 31 insertions(+), 3 deletions(-)

diff --git a/source/blender/gpu/shaders/metal/mtl_shader_defines.msl b/source/blender/gpu/shaders/metal/mtl_shader_defines.msl
index a192e51a0ec..410cf41d116 100644
--- a/source/blender/gpu/shaders/metal/mtl_shader_defines.msl
+++ b/source/blender/gpu/shaders/metal/mtl_shader_defines.msl
@@ -83,9 +83,7 @@ struct constexp_uvec3 {
     uint3 xyz;
   };
 
-  constexpr constexp_uvec3(uint _x, uint _y, uint _z) : x(_x), y(_y), z(_z)
-  {
-  }
+  constexpr constexp_uvec3(uint _x, uint _y, uint _z) : x(_x), y(_y), z(_z) {}
   constexpr uint operator[](int i)
   {
     /* Note: Need to switch on each elem value as array accessor triggers
@@ -270,6 +268,8 @@ struct SStruct {
 #define textureGather3(__tex, __uv, __comp) _texture_gather_internal(__tex, __uv, __comp)
 #define textureGatherOffset(__tex, __offset, __uv, __comp) \
   _texture_gather_internal(__tex, __uv, __comp, __offset)
+#define textureGrad(__tex, __uv, __dpdx, __dpdy) \
+  _texture_grad_internal(__tex, __uv, __dpdx, __dpdy)
 
 #define TEXURE_MACRO(_1, _2, _3, TEXNAME, ...) TEXNAME
 #define texture(...) TEXURE_MACRO(__VA_ARGS__, texture3, texture2)(__VA_ARGS__)
@@ -825,6 +825,34 @@ inline vec<T, 4> _texture_gather_internal(
   return tex.texture->gather(*tex.samp, uva.xy, uint(uva.z), offset);
 }
 
+/* Texture Grad. */
+inline float4 _texture_grad_internal(
+    thread _mtl_combined_image_sampler_2d<float, access::sample> tex,
+    float2 uv,
+    float2 dpdx,
+    float2 dpdy)
+{
+  return tex.texture->sample(*tex.samp, uv, gradient2d(dpdx, dpdy));
+}
+
+inline float4 _texture_grad_internal(
+    thread _mtl_combined_image_sampler_2d_array<float, access::sample> tex,
+    float3 uva,
+    float2 dpdx,
+    float2 dpdy)
+{
+  return tex.texture->sample(*tex.samp, uva.xy, uint(uva.z), gradient2d(dpdx, dpdy));
+}
+
+inline float4 _texture_grad_internal(
+    thread _mtl_combined_image_sampler_3d<float, access::sample> tex,
+    float3 uvw,
+    float3 dpdx,
+    float3 dpdy)
+{
+  return tex.texture->sample(*tex.samp, uvw, gradient3d(dpdx, dpdy));
+}
+
 /* Texture write support. */
 template<typename S, typename T, access A>
 inline void _texture_write_internal(thread _mtl_combined_image_sampler_1d<S, A> tex,
-- 
2.30.2