GPUShaderCreateInfo for interface abstraction

This is a first part of the Shader Create Info system could be.

A shader create info provides a way to define shader structure, resources
and interfaces. This makes for a quick way to provide backend agnostic
binding informations while also making shader variations easy to declare.

- Clear source input (only one file). Cleans up the GPU api since we can create a
  shader from one descriptor
- Resources and interfaces are generated by the backend (much simpler than parsing).
- Bindings are explicit from position in the array.
- GPUShaderInterface becomes a trivial translation of enums and string copy.
- No external dependency to third party lib.
- Cleaner code, less fragmentation of resources in several libs.
- Easy to modify / extend at runtime.
- no parser involve, very easy to code.
- Does not hold any data, can be static and kept on disc.
- Could hold precompiled bytecode for static shaders.

This also includes a new global dependency system.
GLSL shaders can include other sources by using #pragma BLENDER_REQUIRE(...).

This patch already migrated several builtin shaders. Other shaders should be migrated
one at a time, and could be done inside master.

There is a new compile directive `WITH_GPU_SHADER_BUILDER` this is an optional
directive for linting shaders to increase turn around time.

What is remaining:
- pyGPU API {T94975}
- Migration of other shaders. This could be a community effort.

Reviewed By: jbakker

Maniphest Tasks: T94975

Differential Revision: https://developer.blender.org/D13360

1 files changed, 110 insertions, 0 deletions

diff --git a/source/blender/gpu/intern/gpu_shader_shared_utils.h b/source/blender/gpu/intern/gpu_shader_shared_utils.h
new file mode 100644
index 00000000000..7e5d2240851
--- /dev/null
+++ b/source/blender/gpu/intern/gpu_shader_shared_utils.h
@@ -0,0 +1,110 @@
+/*
+ * 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 backend to make it GLSL compatible.
+ *
+ * IMPORTANT:
+ * - Don't add trailing comma at the end of the enum. Our custom pre-processor will noy trim it
+ *   for GLSL.
+ * - 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.
+ * - Always use uint32_t as underlying type.
+ * - Use float suffix by default for float literals to avoid double promotion in C++.
+ * - Pack one float or int after a vec3/ivec3 to fullfil alligment 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 */
+#  pragma once
+
+#  include "BLI_assert.h"
+
+#  ifdef __cplusplus
+#    include "BLI_float2.hh"
+#    include "BLI_float3.hh"
+#    include "BLI_float4.hh"
+#    include "BLI_float4x4.hh"
+/* TODO */
+// #    include "BLI_int2.hh"
+// #    include "BLI_int3.hh"
+#  else
+typedef float float2[2];
+typedef float float3[3];
+typedef float float4[4];
+typedef float float4x4[4][4];
+#  endif
+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 int2[2];
+typedef int int3[2];
+typedef int int4[4];
+typedef int bool1;
+typedef int bool2[2];
+typedef int bool3[2];
+typedef int bool4[4];
+
+#endif
\ No newline at end of file