From dd84b3bef3eb2fcc32cb708210fd658eca2edcad Mon Sep 17 00:00:00 2001
From: Greg Wells <gregory@Gregs-MacBook-Pro.local>
Date: Tue, 1 Jul 2025 12:32:44 -0400
Subject: [PATCH] push constants

---
 .../metal/src/commands/commands/metal_commands.m     |  4 ++--
 .../metal/src/shader_module/metal_shader_module.h    |  1 +
 .../metal/src/shader_module/metal_shader_module.m    | 12 +++++++-----
 3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/projects/apis/metal/src/commands/commands/metal_commands.m b/projects/apis/metal/src/commands/commands/metal_commands.m
index 556ee1a..3fce495 100644
--- a/projects/apis/metal/src/commands/commands/metal_commands.m
+++ b/projects/apis/metal/src/commands/commands/metal_commands.m
@@ -120,7 +120,7 @@ void metalBindUniform(gnCommandBufferHandle buffer, gnUniform uniform, uint32_t
                 if (map.set == set && map.binding == uniform->uniform->bindings[i].binding) {
                     [encoder setVertexBuffer:info.buffer->buffer->buffer
                         offset:info.offset
-                        atIndex:1
+                        atIndex:map.metalBindingIndex
                     ];
                     break;
                 }
@@ -140,5 +140,5 @@ void metalBindUniform(gnCommandBufferHandle buffer, gnUniform uniform, uint32_t
 
 void metalBindVertexBytes(gnCommandBufferHandle buffer, gnPushConstantLayout layout, void* data) {
     id<MTLRenderCommandEncoder> encoder = (id<MTLRenderCommandEncoder>)buffer->commandBuffer->encoder;
-        // [encoder setVertexBytes:data length:layout.size atIndex:0]; // TODO: fix this
+        [encoder setVertexBytes:data length:layout.size atIndex:buffer->commandBuffer->boundGraphcisPipeline->graphicsPipeline->vertexShaderMaps.pushConstantIndex]; // TODO: fix this
 }
diff --git a/projects/apis/metal/src/shader_module/metal_shader_module.h b/projects/apis/metal/src/shader_module/metal_shader_module.h
index 410c3b1..727abf6 100644
--- a/projects/apis/metal/src/shader_module/metal_shader_module.h
+++ b/projects/apis/metal/src/shader_module/metal_shader_module.h
@@ -12,6 +12,7 @@ GN_ARRAY_LIST(metalBindingMap);
 
 typedef struct metalBindingMaps {
     metalBindingMapArrayList uniformBufferMaps;
+    uint32_t pushConstantIndex;
     metalBindingMapArrayList textureMaps;
 } metalBindingMaps;
 
diff --git a/projects/apis/metal/src/shader_module/metal_shader_module.m b/projects/apis/metal/src/shader_module/metal_shader_module.m
index 3ece068..a231a60 100644
--- a/projects/apis/metal/src/shader_module/metal_shader_module.m
+++ b/projects/apis/metal/src/shader_module/metal_shader_module.m
@@ -83,14 +83,16 @@ gnReturnCode createMetalShaderModule(gnShaderModule module, gnDevice device, gnS
 
     spvc_compiler_create_shader_resources(compiler, &resources);
 
-    spvc_resources_get_resource_list_for_type(resources, SPVC_RESOURCE_TYPE_PUSH_CONSTANT, &list, &count);
-    for (int i = 0; i < count; i++) {
-        // TODO: get the buffer index
-    }
-
     module->shaderModule->maps.uniformBufferMaps = loadUniformBufferInformation(resources, compiler, shaderModuleInfo.stage);
     module->shaderModule->maps.textureMaps = loadTextureBindingInformation(resources, compiler);
 
+    spvc_resources_get_resource_list_for_type(resources, SPVC_RESOURCE_TYPE_PUSH_CONSTANT, &list, &count);
+    for (int i = 0; i < count; i++) {
+        spvc_compiler_unset_decoration(compiler, list[i].id, SpvDecorationBinding);
+        module->shaderModule->maps.pushConstantIndex = module->shaderModule->maps.uniformBufferMaps.data[module->shaderModule->maps.uniformBufferMaps.count - 1].metalBindingIndex + 1;
+        spvc_compiler_set_decoration(compiler, list[i].id, SpvDecorationBinding, module->shaderModule->maps.pushConstantIndex);
+    }
+
     spvc_compiler_create_compiler_options(compiler, &options);
     spvc_compiler_options_set_uint(options, SPVC_COMPILER_OPTION_MSL_VERSION, 200);
     spvc_compiler_options_set_bool(options, SPVC_COMPILER_OPTION_MSL_ENABLE_DECORATION_BINDING, true);