From 2fb4d6fac58eefb34c470b226e3f1be946661bc8 Mon Sep 17 00:00:00 2001
From: Evan Hemsley <evan@moonside.games>
Date: Sat, 11 Jan 2025 17:26:32 -0800
Subject: [PATCH] Fix MSL graphics shader buffer order

---
 src/SDL_shadercross.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/src/SDL_shadercross.c b/src/SDL_shadercross.c
index 0e69c4e..85d38e1 100644
--- a/src/SDL_shadercross.c
+++ b/src/SDL_shadercross.c
@@ -1113,19 +1113,19 @@ static SPIRVTranspileContext *SDL_ShaderCross_INTERNAL_TranspileFromSPIRV(
         }
         num_textures += (num_separate_images - num_separate_samplers);
 
-        // Storage buffers
+        // Uniform buffers
         result = spvc_resources_get_resource_list_for_type(
             resources,
-            SPVC_RESOURCE_TYPE_STORAGE_BUFFER,
+            SPVC_RESOURCE_TYPE_UNIFORM_BUFFER,
             (const spvc_reflected_resource **)&reflected_resources,
-            &num_storage_buffers);
+            &num_uniform_buffers);
         if (result < 0) {
             SPVC_ERROR(spvc_resources_get_resource_list_for_type);
             spvc_context_destroy(context);
             return NULL;
         }
 
-        for (size_t i = 0; i < num_storage_buffers; i += 1) {
+        for (size_t i = 0; i < num_uniform_buffers; i += 1) {
             if (!spvc_compiler_has_decoration(compiler, reflected_resources[i].id, SpvDecorationDescriptorSet) || !spvc_compiler_has_decoration(compiler, reflected_resources[i].id, SpvDecorationBinding)) {
                 SDL_SetError("%s", "Shader resources must have descriptor set and binding index!");
                 spvc_context_destroy(context);
@@ -1133,8 +1133,8 @@ static SPIRVTranspileContext *SDL_ShaderCross_INTERNAL_TranspileFromSPIRV(
             }
 
             unsigned int descriptor_set_index = spvc_compiler_get_decoration(compiler, reflected_resources[i].id, SpvDecorationDescriptorSet);
-            if (!(descriptor_set_index == 0 || descriptor_set_index == 2)) {
-                SDL_SetError("%s", "Descriptor set index for graphics storage buffer must be 0 or 2!");
+            if (!(descriptor_set_index == 1 || descriptor_set_index == 3)) {
+                SDL_SetError("%s", "Descriptor set index for graphics uniform buffer must be 1 or 3!");
                 spvc_context_destroy(context);
                 return NULL;
             }
@@ -1152,21 +1152,21 @@ static SPIRVTranspileContext *SDL_ShaderCross_INTERNAL_TranspileFromSPIRV(
                 return NULL;
             }
         }
-        num_buffers += num_storage_buffers;
+        num_buffers += num_uniform_buffers;
 
-        // Uniform buffers
+        // Storage buffers
         result = spvc_resources_get_resource_list_for_type(
             resources,
-            SPVC_RESOURCE_TYPE_UNIFORM_BUFFER,
+            SPVC_RESOURCE_TYPE_STORAGE_BUFFER,
             (const spvc_reflected_resource **)&reflected_resources,
-            &num_uniform_buffers);
+            &num_storage_buffers);
         if (result < 0) {
             SPVC_ERROR(spvc_resources_get_resource_list_for_type);
             spvc_context_destroy(context);
             return NULL;
         }
 
-        for (size_t i = 0; i < num_uniform_buffers; i += 1) {
+        for (size_t i = 0; i < num_storage_buffers; i += 1) {
             if (!spvc_compiler_has_decoration(compiler, reflected_resources[i].id, SpvDecorationDescriptorSet) || !spvc_compiler_has_decoration(compiler, reflected_resources[i].id, SpvDecorationBinding)) {
                 SDL_SetError("%s", "Shader resources must have descriptor set and binding index!");
                 spvc_context_destroy(context);
@@ -1174,8 +1174,8 @@ static SPIRVTranspileContext *SDL_ShaderCross_INTERNAL_TranspileFromSPIRV(
             }
 
             unsigned int descriptor_set_index = spvc_compiler_get_decoration(compiler, reflected_resources[i].id, SpvDecorationDescriptorSet);
-            if (!(descriptor_set_index == 1 || descriptor_set_index == 3)) {
-                SDL_SetError("%s", "Descriptor set index for graphics uniform buffer must be 1 or 3!");
+            if (!(descriptor_set_index == 0 || descriptor_set_index == 2)) {
+                SDL_SetError("%s", "Descriptor set index for graphics storage buffer must be 0 or 2!");
                 spvc_context_destroy(context);
                 return NULL;
             }
@@ -1193,7 +1193,7 @@ static SPIRVTranspileContext *SDL_ShaderCross_INTERNAL_TranspileFromSPIRV(
                 return NULL;
             }
         }
-        num_buffers += num_uniform_buffers;
+        num_buffers += num_storage_buffers;
     }
 
     if (backend == SPVC_BACKEND_MSL && shaderStage == SDL_SHADERCROSS_SHADERSTAGE_COMPUTE) {