Now draws a gradient with compute

CMakeLists.txt

@@ -27,29 +27,73 @@ find_package( VulkanMemoryAllocator CONFIG REQUIRED )
 find_package( fmt REQUIRED )
 # Shader compilers
 # Todo
-#find_program( GLSLANG_VALIDATOR "glslangValidator" HINTS $ENV{VULKAN_SDK}/bin REQUIRED )
 
+add_executable (glslang::validator IMPORTED)
+find_program (GLSLANG_VALIDATOR "glslangValidator" HINTS $ENV{VULKAN_SDK}/bin REQUIRED)
+set_property (TARGET glslang::validator PROPERTY IMPORTED_LOCATION "${GLSLANG_VALIDATOR}")
+find_program(SLANGC_EXECUTABLE slangc HINTS $ENV{VULKAN_SDK}/bin REQUIRED)
 
 # fastgltf because it's not in nixpkgs
 
 FetchContent_Declare(
-    fastgltf
+  fastgltf
-    GIT_REPOSITORY https://github.com/spnda/fastgltf.git
+  GIT_REPOSITORY https://github.com/spnda/fastgltf.git
-    GIT_TAG v0.8.0
+  GIT_TAG v0.8.0
 )
 FetchContent_MakeAvailable(fastgltf)
 
 # vk-bootstrap because CMAKE can't find it on NixOS
 FetchContent_Declare(
-    vk-bootstrap
+  vk-bootstrap
-    GIT_REPOSITORY https://github.com/charles-lunarg/vk-bootstrap.git
+  GIT_REPOSITORY https://github.com/charles-lunarg/vk-bootstrap.git
-    GIT_TAG v1.3.295
+  GIT_TAG v1.3.295
 )
 FetchContent_MakeAvailable(vk-bootstrap)
 
+# Helper functions to build shaders
+function(addGlslShader SOURCE OUTPUT_DIR)
+  get_filename_component(SHADER_NAME ${SOURCE} NAME_WE)
+  set(SPV_FILE "${OUTPUT_DIR}/${SHADER_NAME}.spv")
+  add_custom_command(
+    OUTPUT ${SPV_FILE}
+    COMMAND ${CMAKE_COMMAND} -E make_directory ${OUTPUT_DIR}
+    COMMAND glslang::validator
+      -V
+      --target-env vulkan1.3 # Change if needed
+      -o ${SPV_FILE}
+      ${SOURCE}
+    DEPENDS ${SOURCE}
+    COMMENT "Compiling GLSL shader: ${SOURCE} -> ${SPV_FILE}"
+    VERBATIM
+  )
+  set(SPV_FILE ${SPV_FILE} PARENT_SCOPE)
+endfunction()
+
+
+function(addSlangShader SOURCES ENTRY_POINTS OUTPUT_DIR)
+  set(SPV_FILE "${OUTPUT_DIR}/slang.spv")
+  add_custom_command(
+    OUTPUT ${SPV_FILE}
+    COMMAND ${CMAKE_COMMAND} -E make_directory ${OUTPUT_DIR}
+    COMMAND ${SLANGC_EXECUTABLE}
+      ${SOURCES}
+      -target spirv
+      -profile spirv_1_4+spvRayQueryKHR # Change if needed
+      -emit-spirv-directly
+      -fvk-use-entrypoint-name
+      ${ENTRY_POINTS}
+      -o ${SPV_FILE}
+    DEPENDS ${SOURCES}
+    COMMENT "Compiling Slang shaders -> ${SPV_FILE}"
+    VERBATIM
+  )
+  set(SPV_FILE ${SPV_FILE} PARENT_SCOPE)
+endfunction()
+
+
 # A function to automate executables aditions
 function ( addBinary BINARY_NAME )
-  cmake_parse_arguments ( BINARY "" "SOURCE" "SHADER;LIBS;TEXTURES;MODELS" ${ARGN} )
+  cmake_parse_arguments ( BINARY "" "SOURCE" "SHADERS;SLANG_SHADERS;LIBS;TEXTURES;MODELS" ${ARGN} )
   if (DEFINED BINARY_SOURCE)
     add_executable ( ${BINARY_NAME} src/${BINARY_SOURCE}.cpp )
   endif()
@@ -75,7 +119,30 @@ function ( addBinary BINARY_NAME )
     BUILD_ID="${ENGINE_VERSION}"
   )
 
+  if(DEFINED BINARY_SHADERS)
+    set(SHADER_OUTPUT_DIR ${CMAKE_BINARY_DIR}/${BINARY_NAME}/shaders)
+    set(ALL_SPV_FILES "")
+    foreach(SHADER_SRC ${BINARY_SHADERS})
+      if(NOT IS_ABSOLUTE ${SHADER_SRC})
+        set(SHADER_SRC ${CMAKE_CURRENT_SOURCE_DIR}/${SHADER_SRC})
+      endif()
+      addGlslShader(${SHADER_SRC} ${SHADER_OUTPUT_DIR})
+      list(APPEND ALL_SPV_FILES ${SPV_FILE})
+    endforeach()
 
+    add_custom_target(shaders_${BINARY_NAME} DEPENDS ${ALL_SPV_FILES})
+    add_dependencies(${BINARY_NAME} shaders_${BINARY_NAME})
+  endif()
+
+  if(DEFINED BINARY_SLANG_SHADERS)
+    set(SLANG_OUTPUT_DIR ${CMAKE_BINARY_DIR}/${BINARY_NAME}/shaders)
+    if(NOT DEFINED BINARY_SLANG_ENTRIES)
+      message(FATAL_ERROR "addBinary: SLANG_SHADERS nécessite SLANG_ENTRIES")
+    endif()
+    addSlangShader("${BINARY_SLANG_SHADERS}" "${BINARY_SLANG_ENTRIES}" ${SLANG_OUTPUT_DIR})
+    add_custom_target(slang_shaders_${BINARY_NAME} DEPENDS ${SPV_FILE})
+    add_dependencies(${BINARY_NAME} slang_shaders_${BINARY_NAME})
+  endif()
 
   if (DEFINED BINARY_LIBS)
     target_link_libraries ( ${BINARY_NAME} ${BINARY_LIBS} )
@@ -116,6 +183,7 @@ addBinary (
   engine
   SOURCE Engine/main
 
+  SHADERS shaders/gradient.comp
   LIBS glfw fmt vk-bootstrap vulkan
 )
 

src/Engine/engine/engine.h

@@ -5,6 +5,8 @@
 
 #include "descriptors.h" // Required for public interface custom allocator
 #include "Common/Types.h"
+#include <GLFW/glfw3.h>
+#include <fmt/base.h>
 #include <vulkan/vulkan_core.h>
 
 
@@ -62,6 +64,10 @@ class Engine {
     VkDescriptorSet           _drawImageDescriptors;
     VkDescriptorSetLayout     _drawImageDescriptorLayout;
 
+    // Pipelines
+    VkPipeline                _gradientPipeline;
+    VkPipelineLayout          _gradientPipelineLayout;
+
 
     void init();
 
@@ -77,6 +83,8 @@ class Engine {
     void initSwapchain();
     void initCommands();
     void initSyncStructures();
+    void initPipelines();
+    void initBackgroundPipelines();
 
     void createSwapchain(
       uint32_t width,
@@ -101,6 +109,7 @@ class Engine {
 #define IMAGES_IMPL
 #define INITIALIZERS_IMPL
 #define DESCRIPTORS_IMPL
+#define PIPELINES_IMPL
 #define CALLBACK_IMPL
 #define TIMER_IMPL
 #define TYPES_IMPL
@@ -111,6 +120,7 @@ class Engine {
 #include "initializers.h"
 #include "callbacks.h"
 #include "descriptors.h"
+#include "pipelines.h"
 #include "Common/Types.h"
 #include "Common/Timer.h"
 
@@ -369,6 +379,7 @@ void Engine::initRender() {
   initCommands();
   initSyncStructures();
   initDescriptors();
+  initPipelines();
 }
 
 void Engine::initVulkan() {
@@ -656,6 +667,100 @@ void Engine::initDescriptors(){
   #endif
 }
 
+void Engine::initPipelines() {
+  #ifdef DEBUG
+  fmt::println("[Engine:Init] Initializing pipelines...");
+  #endif
+  initBackgroundPipelines();
+
+  #ifdef DEBUG
+  fmt::println("[Engine:Init] Pipelines initialized !");
+  #endif
+}
+
+void Engine::initBackgroundPipelines() {
+  #ifdef DEBUG
+  fmt::println("[Engine:Init] Initializing compute pipelines...");
+  #endif
+  VkPipelineLayoutCreateInfo computeLayout {
+    .sType          = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO,
+    .pNext          = nullptr,
+    .setLayoutCount = 1,
+    .pSetLayouts    = &_drawImageDescriptorLayout
+  };
+
+  VK_CHECK(
+    vkCreatePipelineLayout(
+      _device,
+      &computeLayout,
+      nullptr,
+      &_gradientPipelineLayout
+    );
+  );
+
+  // Create the actual shader
+  VkShaderModule computeDrawShader;
+  if (
+    !vkutil::loadShaderModule(
+      "shaders/gradient.spv",
+      _device,
+      &computeDrawShader
+    )
+  ) {
+    fmt::println("[Engine:Error] Error when building the compute shader !");
+  }
+
+  VkPipelineShaderStageCreateInfo stageInfo{
+    .sType    = VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_CREATE_INFO,
+    .pNext    = nullptr,
+    .stage    = VK_SHADER_STAGE_COMPUTE_BIT,
+    .module   = computeDrawShader,
+    .pName    = "main"
+  };
+
+  VkComputePipelineCreateInfo computePipelineCreateInfo {
+    .sType    = VK_STRUCTURE_TYPE_COMPUTE_PIPELINE_CREATE_INFO,
+    .pNext    = nullptr,
+    .stage    = stageInfo,
+    .layout   = _gradientPipelineLayout
+  };
+
+  VK_CHECK(
+    vkCreateComputePipelines(
+      _device,
+      VK_NULL_HANDLE,
+      1,
+      &computePipelineCreateInfo,
+      nullptr,
+      &_gradientPipeline
+    );
+  );
+
+  // Do some cleanup
+  vkDestroyShaderModule(
+    _device,
+    computeDrawShader,
+    nullptr
+  );
+
+  _mainDeletionQueue.pushFunction([this]() {
+    vkDestroyPipelineLayout(
+      _device,
+      _gradientPipelineLayout,
+      nullptr
+    );
+
+    vkDestroyPipeline(
+      _device,
+      _gradientPipeline,
+      nullptr
+    );
+  });
+  #ifdef DEBUG
+  fmt::println("[Engine:Init] Compute pipelines initalized !");
+  #endif
+}
+
 //================================
 //=== Render-related Functions ===
 //================================
@@ -682,7 +787,9 @@ void Engine::createSwapchain(
         .colorSpace = VK_COLOR_SPACE_SRGB_NONLINEAR_KHR
       }
     )
-    .set_desired_present_mode(VK_PRESENT_MODE_FIFO_KHR) // VSync
+    .set_desired_present_mode(VK_PRESENT_MODE_FIFO_KHR)
+    // FIFO = VSync
+    // Mailbox = Unapped
     .set_desired_extent(width, height)
     .add_image_usage_flags(VK_IMAGE_USAGE_TRANSFER_DST_BIT)
     .build()
@@ -710,7 +817,7 @@ void Engine::destroySwapchain() {
   }
 
   #ifdef DEBUG
-  fmt::println("[Engine:Cleanup]Swapchain destroyed !");
+  fmt::println("[Engine:Cleanup] Swapchain destroyed !");
   #endif
 }
 
@@ -725,15 +832,34 @@ void Engine::drawBackground(
 
   VkImageSubresourceRange clearRange = vkinit::imageSubresourceRange(VK_IMAGE_ASPECT_COLOR_BIT);
 
-  // Clear Image
+  vkCmdBindPipeline(
-  vkCmdClearColorImage(
     cmd,
-    _drawImage.image,
+    VK_PIPELINE_BIND_POINT_COMPUTE,
-    VK_IMAGE_LAYOUT_GENERAL,
+    _gradientPipeline
-    &clearValue,
-    1,
-    &clearRange
   );
+
+  vkCmdBindDescriptorSets(
+    cmd,
+    VK_PIPELINE_BIND_POINT_COMPUTE,
+    _gradientPipelineLayout,
+    0,
+    1,
+    &_drawImageDescriptors,
+    0,
+    nullptr
+  );
+
+  vkCmdDispatch(
+    cmd,
+    std::ceil(
+      _drawExtent.width / 16.0
+    ),
+    std::ceil(
+      _drawExtent.height / 16.0
+    ),
+    1
+  );
+
 }
 
 

src/Engine/engine/pipelines.h

@@ -2,12 +2,95 @@
 #define PIPELINES_H
 // Normal header
 
+#include "Common/Types.h"
+#include <cstddef>
+#include <cstdint>
+#include <fmt/base.h>
+#include <vector>
+#include <vulkan/vulkan_core.h>
+
+namespace vkutil {
+  bool loadShaderModule(
+    const char* filePath,
+    VkDevice device,
+    VkShaderModule* outShaderModule
+  );
+};
+
 #endif
 
 #ifdef PIPELINES_IMPL
 #ifndef PIPELINES_IMPL_H
 #define PIPELINES_IMPL_H
 // Implementation
+// Imports
+#include <fstream>
+
+// Custom imports
+#include "initializers.h"
+
+namespace vkutil {
+  bool loadShaderModule(
+    const char* filePath,
+    VkDevice device,
+    VkShaderModule* outShaderModule
+  ) {
+    #ifdef DEBUG
+    fmt::println("[Engine:Utils] Loading shader located at {}...", filePath);
+    #endif
+    // Open the file, with the cursor at the end
+    std::ifstream file(
+      filePath,
+      std::ios::ate | std::ios::binary
+    );
+
+    if (!file.is_open()) {
+      return false;
+    }
+
+    // Find the size of the file by looking
+    // at the cursor
+    size_t fileSize = (size_t)file.tellg();
+
+    // Allocate a big enough vector to suit SPIR-V
+    std::vector<uint32_t> buffer(fileSize/ sizeof(uint32_t));
+
+    file.seekg(0); // Put the cursor at the begining
+
+    // Load the file in the buffer
+    file.read((char*)buffer.data(), fileSize);
+
+    file.close();
+
+    // Create the shader module
+    VkShaderModuleCreateInfo createInfo {
+      .sType    = VK_STRUCTURE_TYPE_SHADER_MODULE_CREATE_INFO,
+      .pNext    = nullptr,
+      .codeSize = buffer.size() * sizeof(uint32_t), // Convert to bytes
+      .pCode    = buffer.data()
+    };
+
+    // Check that everything went well
+    VkShaderModule shaderModule;
+
+    if (vkCreateShaderModule(
+      device,
+      &createInfo,
+      nullptr,
+      &shaderModule
+    ) != VK_SUCCESS){
+      return false;
+    }
+    *outShaderModule = shaderModule;
+
+    #ifdef DEBUG
+    fmt::println("[Engine:Utils] Shader loaded from {} and size {}", filePath, fileSize);
+    #endif
+
+    return true;
+    }
+};
+
 
 #endif
 #endif