From d3f5d87d613a7a2190c3bc86234c49c274e13b3d Mon Sep 17 00:00:00 2001
From: PancakeTAS <pancake@mgnet.work>
Date: Sun, 29 Jun 2025 16:52:01 +0200
Subject: [PATCH] more comfortable way to initialize shader

---
 include/core/shadermodule.hpp |  3 ++-
 src/core/shadermodule.cpp     | 20 +++++++++++---------
 src/main.cpp                  | 17 ++++-------------
 3 files changed, 17 insertions(+), 23 deletions(-)

diff --git a/include/core/shadermodule.hpp b/include/core/shadermodule.hpp
index 4ef8390..9971f56 100644
--- a/include/core/shadermodule.hpp
+++ b/include/core/shadermodule.hpp
@@ -3,6 +3,7 @@
 
 #include "device.hpp"
 
+#include <utility>
 #include <vulkan/vulkan_core.h>
 
 #include <string>
@@ -30,7 +31,7 @@ namespace Vulkan::Core {
         /// @throws ls::vulkan_error if object creation fails.
         ///
         ShaderModule(const Device& device, const std::string& path,
-            std::vector<VkDescriptorType> descriptorTypes);
+            const std::vector<std::pair<size_t, VkDescriptorType>>& descriptorTypes);
 
         /// Get the Vulkan handle.
         [[nodiscard]] auto handle() const { return *this->shaderModule; }
diff --git a/src/core/shadermodule.cpp b/src/core/shadermodule.cpp
index f7258d6..703b609 100644
--- a/src/core/shadermodule.cpp
+++ b/src/core/shadermodule.cpp
@@ -7,7 +7,7 @@
 using namespace Vulkan::Core;
 
 ShaderModule::ShaderModule(const Device& device, const std::string& path,
-        std::vector<VkDescriptorType> descriptorTypes) {
+        const std::vector<std::pair<size_t, VkDescriptorType>>& descriptorTypes) {
     if (!device)
         throw std::invalid_argument("Invalid Vulkan device");
 
@@ -46,14 +46,16 @@ ShaderModule::ShaderModule(const Device& device, const std::string& path,
     );
 
     // create descriptor set layout
-    std::vector<VkDescriptorSetLayoutBinding> layoutBindings(descriptorTypes.size());
-    for (size_t i = 0; i < descriptorTypes.size(); ++i)
-        layoutBindings.at(i) = {
-            .binding = static_cast<uint32_t>(i),
-            .descriptorType = descriptorTypes.at(i),
-            .descriptorCount = 1,
-            .stageFlags = VK_SHADER_STAGE_COMPUTE_BIT
-        };
+    std::vector<VkDescriptorSetLayoutBinding> layoutBindings;
+    size_t bindIdx = 0;
+    for (const auto &[count, type] : descriptorTypes)
+        for (size_t i = 0; i < count; i++, bindIdx++)
+            layoutBindings.emplace_back(VkDescriptorSetLayoutBinding {
+                .binding = static_cast<uint32_t>(bindIdx),
+                .descriptorType = type,
+                .descriptorCount = 1,
+                .stageFlags = VK_SHADER_STAGE_COMPUTE_BIT
+            });
 
     const VkDescriptorSetLayoutCreateInfo layoutDesc{
         .sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_LAYOUT_CREATE_INFO,
diff --git a/src/main.cpp b/src/main.cpp
index b4df0a9..d55ef02 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -11,19 +11,10 @@ int main() {
     const Vulkan::Device device(instance);
 
     const Vulkan::Core::ShaderModule computeShader(device, "shaders/downsample.spv",
-        {
-            VK_DESCRIPTOR_TYPE_SAMPLER,
-            VK_DESCRIPTOR_TYPE_SAMPLED_IMAGE,
-            VK_DESCRIPTOR_TYPE_STORAGE_IMAGE,
-            VK_DESCRIPTOR_TYPE_STORAGE_IMAGE,
-            VK_DESCRIPTOR_TYPE_STORAGE_IMAGE,
-            VK_DESCRIPTOR_TYPE_STORAGE_IMAGE,
-            VK_DESCRIPTOR_TYPE_STORAGE_IMAGE,
-            VK_DESCRIPTOR_TYPE_STORAGE_IMAGE,
-            VK_DESCRIPTOR_TYPE_STORAGE_IMAGE,
-            VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER
-        }
-    );
+        { { 1, VK_DESCRIPTOR_TYPE_SAMPLER},
+          { 1, VK_DESCRIPTOR_TYPE_SAMPLED_IMAGE},
+          { 7, VK_DESCRIPTOR_TYPE_STORAGE_IMAGE},
+          { 1, VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER} });
     const Vulkan::Core::Pipeline computePipeline(device, computeShader);
 
     std::cerr << "Application finished" << '\n';