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diff --git a/source/blender/gpu/GPU_shader_shared_utils.h b/source/blender/gpu/GPU_shader_shared_utils.h
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+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2022 Blender Foundation.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup gpu
+ *
+ * Glue definition to make shared declaration of struct & functions work in both C / C++ and GLSL.
+ * We use the same vector and matrix types as Blender C++. Some math functions are defined to use
+ * the float version to match the GLSL syntax.
+ * This file can be used for C & C++ code and the syntax used should follow the same rules.
+ * Some preprocessing is done by the GPU back-end to make it GLSL compatible.
+ *
+ * IMPORTANT:
+ * - Always use `u` suffix for enum values. GLSL do not support implicit cast.
+ * - Define all values. This is in order to simplify custom pre-processor code.
+ * - (C++ only) Always use `uint32_t` as underlying type (`enum eMyEnum : uint32_t`).
+ * - (C only) do NOT use the enum type inside UBO/SSBO structs and use `uint` instead.
+ * - Use float suffix by default for float literals to avoid double promotion in C++.
+ * - Pack one float or int after a vec3/ivec3 to fulfill alignment rules.
+ *
+ * NOTE: Due to alignment restriction and buggy drivers, do not try to use mat3 inside structs.
+ * NOTE: (UBO only) Do not use arrays of float. They are padded to arrays of vec4 and are not worth
+ * it. This does not apply to SSBO.
+ *
+ * IMPORTANT: Do not forget to align mat4, vec3 and vec4 to 16 bytes, and vec2 to 8 bytes.
+ *
+ * NOTE: You can use bool type using bool1 a int boolean type matching the GLSL type.
+ */
+
+#ifdef GPU_SHADER
+#  define BLI_STATIC_ASSERT_ALIGN(type_, align_)
+#  define BLI_STATIC_ASSERT_SIZE(type_, size_)
+#  define static
+#  define inline
+#  define cosf cos
+#  define sinf sin
+#  define tanf tan
+#  define acosf acos
+#  define asinf asin
+#  define atanf atan
+#  define floorf floor
+#  define ceilf ceil
+#  define sqrtf sqrt
+
+#  define float2 vec2
+#  define float3 vec3
+#  define float4 vec4
+#  define float4x4 mat4
+#  define int2 ivec2
+#  define int3 ivec3
+#  define int4 ivec4
+#  define uint2 uvec2
+#  define uint3 uvec3
+#  define uint4 uvec4
+#  define bool1 bool
+#  define bool2 bvec2
+#  define bool3 bvec3
+#  define bool4 bvec4
+
+#else /* C / C++ */
+#  pragma once
+
+#  include "BLI_assert.h"
+
+#  ifdef __cplusplus
+#    include "BLI_float4x4.hh"
+#    include "BLI_math_vec_types.hh"
+using blender::float2;
+using blender::float3;
+using blender::float4;
+using blender::float4x4;
+using blender::int2;
+using blender::int3;
+using blender::int4;
+using blender::uint2;
+using blender::uint3;
+using blender::uint4;
+using bool1 = int;
+using bool2 = blender::int2;
+using bool3 = blender::int3;
+using bool4 = blender::int4;
+
+#  else /* C */
+typedef float float2[2];
+typedef float float3[3];
+typedef float float4[4];
+typedef float float4x4[4][4];
+typedef int int2[2];
+typedef int int3[2];
+typedef int int4[4];
+typedef uint uint2[2];
+typedef uint uint3[3];
+typedef uint uint4[4];
+typedef int bool1;
+typedef int bool2[2];
+typedef int bool3[2];
+typedef int bool4[4];
+#  endif
+
+#endif