Implement Binary Shader Compilation

* Added an extra stage before compiling shader, which is generating a binary blob.
* On Vulkan, this allows caching the SPIRV reflection information, which is expensive to parse.
* On other (future) RenderingDevices, it allows caching converted binary data, such as DXIL or MSL.

This PR makes the shader cache include the reflection information, hence editor startup times are significantly improved.
I tested this well and it appears to work, and I added a lot of consistency checks, but because it includes writing and reading binary information, rare bugs may pop up, so be aware.
There was not much of a choice for storing the reflection information, given shaders can be a lot, take a lot of space and take time to parse.

2 files changed, 9 insertions, 9 deletions

diff --git a/modules/glslang/register_types.cpp b/modules/glslang/register_types.cpp
index 730c6b89f7..dd545ff431 100644
--- a/modules/glslang/register_types.cpp
+++ b/modules/glslang/register_types.cpp
@@ -193,7 +193,7 @@ void preregister_glslang_types() {
 	// initialize in case it's not initialized. This is done once per thread
 	// and it's safe to call multiple times
 	glslang::InitializeProcess();
-	RenderingDevice::shader_set_compile_function(_compile_shader_glsl);
+	RenderingDevice::shader_set_compile_to_spirv_function(_compile_shader_glsl);
 	RenderingDevice::shader_set_get_cache_key_function(_get_cache_key_function_glsl);
 }
 
diff --git a/modules/lightmapper_rd/lightmapper_rd.cpp b/modules/lightmapper_rd/lightmapper_rd.cpp
index b75cf6502e..fe941e25e7 100644
--- a/modules/lightmapper_rd/lightmapper_rd.cpp
+++ b/modules/lightmapper_rd/lightmapper_rd.cpp
@@ -794,7 +794,7 @@ LightmapperRD::BakeError LightmapperRD::bake(BakeQuality p_quality, bool p_use_d
 	}
 	ERR_FAIL_COND_V(err != OK, BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES);
 
-	RID rasterize_shader = rd->shader_create_from_bytecode(raster_shader->get_bytecode());
+	RID rasterize_shader = rd->shader_create_from_spirv(raster_shader->get_spirv_stages());
 
 	ERR_FAIL_COND_V(rasterize_shader.is_null(), BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES); //this is a bug check, though, should not happen
 
@@ -945,27 +945,27 @@ LightmapperRD::BakeError LightmapperRD::bake(BakeQuality p_quality, bool p_use_d
 	ERR_FAIL_COND_V(err != OK, BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES);
 
 	// Unoccluder
-	RID compute_shader_unocclude = rd->shader_create_from_bytecode(compute_shader->get_bytecode("unocclude"));
+	RID compute_shader_unocclude = rd->shader_create_from_spirv(compute_shader->get_spirv_stages("unocclude"));
 	ERR_FAIL_COND_V(compute_shader_unocclude.is_null(), BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES); // internal check, should not happen
 	RID compute_shader_unocclude_pipeline = rd->compute_pipeline_create(compute_shader_unocclude);
 
 	// Direct light
-	RID compute_shader_primary = rd->shader_create_from_bytecode(compute_shader->get_bytecode("primary"));
+	RID compute_shader_primary = rd->shader_create_from_spirv(compute_shader->get_spirv_stages("primary"));
 	ERR_FAIL_COND_V(compute_shader_primary.is_null(), BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES); // internal check, should not happen
 	RID compute_shader_primary_pipeline = rd->compute_pipeline_create(compute_shader_primary);
 
 	// Indirect light
-	RID compute_shader_secondary = rd->shader_create_from_bytecode(compute_shader->get_bytecode("secondary"));
+	RID compute_shader_secondary = rd->shader_create_from_spirv(compute_shader->get_spirv_stages("secondary"));
 	ERR_FAIL_COND_V(compute_shader_secondary.is_null(), BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES); //internal check, should not happen
 	RID compute_shader_secondary_pipeline = rd->compute_pipeline_create(compute_shader_secondary);
 
 	// Dilate
-	RID compute_shader_dilate = rd->shader_create_from_bytecode(compute_shader->get_bytecode("dilate"));
+	RID compute_shader_dilate = rd->shader_create_from_spirv(compute_shader->get_spirv_stages("dilate"));
 	ERR_FAIL_COND_V(compute_shader_dilate.is_null(), BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES); //internal check, should not happen
 	RID compute_shader_dilate_pipeline = rd->compute_pipeline_create(compute_shader_dilate);
 
 	// Light probes
-	RID compute_shader_light_probes = rd->shader_create_from_bytecode(compute_shader->get_bytecode("light_probes"));
+	RID compute_shader_light_probes = rd->shader_create_from_spirv(compute_shader->get_spirv_stages("light_probes"));
 	ERR_FAIL_COND_V(compute_shader_light_probes.is_null(), BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES); //internal check, should not happen
 	RID compute_shader_light_probes_pipeline = rd->compute_pipeline_create(compute_shader_light_probes);
 
@@ -1506,11 +1506,11 @@ LightmapperRD::BakeError LightmapperRD::bake(BakeQuality p_quality, bool p_use_d
 	}
 	ERR_FAIL_COND_V(err != OK, BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES);
 
-	RID blendseams_line_raster_shader = rd->shader_create_from_bytecode(blendseams_shader->get_bytecode("lines"));
+	RID blendseams_line_raster_shader = rd->shader_create_from_spirv(blendseams_shader->get_spirv_stages("lines"));
 
 	ERR_FAIL_COND_V(blendseams_line_raster_shader.is_null(), BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES);
 
-	RID blendseams_triangle_raster_shader = rd->shader_create_from_bytecode(blendseams_shader->get_bytecode("triangles"));
+	RID blendseams_triangle_raster_shader = rd->shader_create_from_spirv(blendseams_shader->get_spirv_stages("triangles"));
 
 	ERR_FAIL_COND_V(blendseams_triangle_raster_shader.is_null(), BAKE_ERROR_LIGHTMAP_CANT_PRE_BAKE_MESHES);